SINCGARS-V CSC 1985 SUBJECT AREA C4 SINCGARS-V Major G.E. Washburn Conference Group 12 Individual Research Colonel Kline SINCGARS-V Table of Contents INTRODUCTION 1 CHAPTER 1: SPREAD SPECTRUM TECHNOLOGY 3 CHAPTER 2: THREAT 10 CHAPTER 3: FREQUENCY HOPPING VS THE THREAT 15 CHAPTER 4: PROJECTED USAGE 21 CHAPTER 5: FREQUENCY MANAGEMENT 27 CHAPTER 6: CAPABILITIES 35 CHAPTER 7: LIMITATIONS 39 CONCLUSION 52 INTRODUCTION In the mid 1970's, the United States Army began development of a new generation of tactical radios entitled Single-Channel Ground and Airborne Radio Subsystem - Very High Frequency (SINCGARS-V). SINCGARS-V was to provide a replacement for the present AN/PRC-77 and AN/VRC-12 series equipment. Procurement or SINCGARS-V was to include approx- imately 160,000 radios for the Army and 20,000 radios for the Marine Corps. The planned introduction of SINCGARS-V into the Marine Corps inventory brings about two significant developments. First, the radio will provide digital communications down to the platoon level. Second, SINCGARS-V introduces frequency hopping, a technology designed to provide protec- tion from enemy Electronic Counter Measures. The new capabilities of SINCGARS-V have necessitated a review or present employment doctrine for radios in the VHF-FM band both for amphibious operations and land opera- tions. The need to review present doctrine and also the impact or SINCGARS-V on freguency management procedures resulted in the submission of a research topic to the Command and Staff College by the Telecommunications Branch, C4 Division, Headquarters Marine Corps. The scope of this study was originally aimed at the freguency management issue. The scope was expanded to include emploment doctrine after a face-to-face meeting with the Headquarters Marine Corps Project Officer. Using these two issues as a basis, the scope was again expanded to provide an overview of the significant issues pertaining to SINCGARS-V. Objective research regarding SINCGARS-V has proven to be very difficult. The proponents and critics of the system are equally intense and convincing. The discussions which follow are offered as objective analysis. This study is by no means inclusive. A great deal of the significant infor- mation regarding SINCGARS-V is either classified or closely guarded by those associated with the project. The material presented is unclassified and has been developed from technical journals, official government reports and numerous conversations with both military and civilian personnel associated with the development and operational testing of SINCGARS-V. It is also necessary to note that information was not requested directly from the program manager. Official reports were provided by the Electromagnetic Compatability Analysis Center with the concurrence or the Army Project Office. This study is directed toward individuals who are familiar with tactical communications. Exhaustive explana- tions of basic communications terms and concepts have not been included. SPREAD SPECTRUM TECHNOLOGY It is generally acknowledged that United States Armed Forces rely greatly upon command and control as force multipliers. Advance technology greatly enhances a comman- der's ability to remain abreast of a battlefield situation, affording him a brief opportunity to act or react in the most effective manner. To be successful, a commander must retain the capability to integrate the actions of his forces and their weapons systems. This coordinated effort pro- duces an economy of force. While units in the field can physically protect their systems and installations, there is little protection for the vital communications links which provide both command and control. Since the beginning of the conflict in South Vietnam, a great deal of attention has been focused on the develop- ment of a means to protect both tactical and strategic communications links. The extraordinary growth of the international communications industry has had a dramatic effect on the military race to gain control of the unre- stricted use of the electromagnetic spectrum. Technological breakthroughs have produced more secure, reliable and flex- ible communications systems. These developments have also spawned a counter-technology oriented toward selectively degrading or destroying these improved systems. The conflict between these two disparate technologies is far from its conclusion. Electronic Warfare (EW) has been legitimized as a very crucial facet of the modern battlefield. The Soviet Union, as well as a multitude of other nations have recognized the importance of denying an adversary's use of the spectrum. The loss of the ability to command and control would devastate the operations of an American force. Economy of force cannot be achieved and thus, the probability of parity with a numerically superior force is greatly diminished. United States doctrine breaks the general idea of Electronic Warfare into several major subdivisions. These include Electronic Warfare Support Measures(ESM), Electronic Countermeasures (ECM), and Electronic Counter-Countermeasures (ECCM). ESM includes actions taken to search for, intercept, locate and rapidly identify radiated electromagnetic energy for the purpose of immediately exploiting it for military advantages. ESM provides the information base required for the employment of Electronic Countermeasures and Electronic Counter-Countermeasures. ECM is comprised of two elements. A hostile station can either attempt to prevent the passage of information by jamming or to provide false information through electronic deception. ECCM are those measures taken to prevent an adversary from employing ECM against friendly communication links. ECCM is provided both by operator training and through the use of electronic technology. ECCM has evolved over the past two decades. Initial emphasis was on protecting the information transmitted from one station to another. As the Soviets invested heavily in Radio-Electronic Combat (REC), this technique lost a portion of its utility. A renewed interest by Soviets in locating and successfully jamming threat stations introduced a form of electronic hide and seek. As the Soviet Union expanded its technology base, and coincidentally, reliance on electronic means for effecting command and control, it became apparent that jamming on the battlefield would have to be employed in a fairly sophisticated and discriminating manner to avoid the total elimination of all electronic communications. The massive Soviet Radio-Electronic Combat threat promoted intense research efforts in the West. Although much of this research was conducted independently over national and corporate lines, a consensus was recognized regarding the general requirements for a new generation of tactical battlefield communications equipment. Tactical communications systems must provide message security and some form of ECCM. The Western defense industry began analyzing the postulated threat and plausible methods of combating it. Several private-venture programs emerged which were directed toward producing the technology for an integral form of ECCM. The industry effort was concentrated on the Very High Frequency (VHF) portion of the electromagnetic spectrum because it is the most widely used frequency band on the battlefield. VHF communications contain the preponderance of combat net radios and tactical command and control links. Several techniques and areas of technology have been investigated within the electronics industry. This research examined numerous options ranging from the improvement of conventional single-channel radios which operate on a fixed frequency or time agility. Of the two high technology solutions, frequency hopping has gained favor because of relative simplicity and lower cost. Although the threat will be analyzed in detail in another section of this paper, it is necessary here to provide a short description to assist in explaining exactly what a frequency hopping radio is. At present, there are two predominant Electronic Warfare techniques which may be employed to disrupt radio traffic. An adversary can attempt to jam a wide band of frequencies or direct jam a relatively few high priority transmission paths. The use of wideband jammers has a distinct disadvantage. The efficiency of wideband jammers is dependent upon the degree of saturation which can be achieved in the operational bandwidths. An effective wideband jammer makes no distinc- tion between friendly communications and those of the enemy. The probability of encountering wideband jamming is a con- tinuing source of speculation. Assuming that an enemy must employ some portion of the electromagnetic spectrum to control his operations, it is very likely that jamming may primarily be employed against only selected, high value transmission links. In order to attack a specific link, it is necessary to monitor a range of frequencies to determine whether or not a transmission is being attempted. The output signal of a frequency hopping radio and the tuning of its cor- responding receiver are synchronized and hop (or switch) over a range of frequencies in a random manner.1 Theori- tically, it is impossible to predict the changes in the frequency hopset without a basic key. The time spent on any frequency is so short that is is virtually impossible to detect the signal. Another form of protection stems from the short period this type of radio remains on a single frequency. In the event enemy equipment could be produced which would be capable of intercepting a short burst of signal on a single frequency before the radio link hops to the next, it would not be able to associate the short transmission with a particular net.2 If a large number of frequency hoppers are employed in an area, the task of intercepting, follow- ing and jamming becomes immensely complicated, if not impossible. Many of these statements must be qualified. There have been some new developments in the EW threat and also some problems associated with the saturation of the battlefield with frequency hopping radios. These issues will be discussed in depth later in this report. A great deal of interest has been demonstrated regard- ing spread spectrum technology. Extensive research by private and national weapons manufacturers has produced an array of equipment. Generally speaking, these systems can be categorized as either slow, medium or fast frequency hopping radios. Because such radios do not attempt to overpower, but rather, to elude enemy jammers, an important performance characteristic is the number of times the radio hops from one frequency to another relative to time. The slow hop is usually thought of as 100 to 200 hops per second; fast hop as 1000 hops per second; and medium hop as falling somewhere in between the other two. Although hop rate is always employed when categorizing different systems, it is only off indirect significance. The hope rate is related to what some industry analysts consider the pre- dominant factor - dwell time.3 To elaborate further, dwell time is the period when the transmitter is on and its target receiver is listening. The enemy's ability to find a transmission in a shorter period than the dwell time, permits him to jam the transmission as well as follow it. Current development programs in this area of technology are many. At present, the only corporation pursuing the production of a fast frequency hopping radio is Rockwell- Collins.4 Slow and medium frequency hopping radios are being developed by Australia, Sweden, France, South Africa, Israel, and the United States. Among the competing manu- facturers are International Telephone and Telegraph (ITT), Plessey, Rural, Thompson-CSF, Marconi Space and Defense Systems (MSDS), Harris and Tadiran. The project logos include: SINCGARS-V, Project Raven, Scimitar, Jaguar and Shamir.5 The United States Army has evaluated three frequency hopping radio systems. The contractors involved in the competition were Rockwell-Collins, ITT, and Cincinnati Electronics. The expensive fast hopping radio produced by Rockwell-Collins was the first to be removed from competi- tion. ITT was selected over Cincinnati Electronics in the production of the slow/medium hopping SINCGARS-V. Because the Marine Corps will be relying on the Army for the pro- curement of the new generation of tactical radios, there is a great deal to be gained from analyzing the performance of the ITT SINCGARS-V. THREAT The SINCGARS-V System is being developed to reduce the Soviet's ability to intercept, direction find, and jam tactical radio nets. Specific Soviet jammers include the barrage jammer and the narrowband or spot noise jammer. It also appears that in the foreseeable future the Russians will be able to produce a transponder, known as a follower jammer. This type of jammer is being developed specifically to defeat the new generation of slow frequency hopping tactical radios. The narrowband jammer does not pose a serious threat to any of the frequency hoppers. Targeted on an assigned frequency or range of frequencies, the frequency hopper only occasionally arrives on the jammer frequency. When successful jamming occurs, it can only affect the message bits being transmitted in the particular hopping cycle (dwell). To be successful in this limited form of jamming, a jammer frequency must be on one of the frequencies included in the hopset and the jammer must have sufficient power to overcome the hopping signal.6 Attempts to change the jammer frequency require a great deal of time relative to the hopping of the target system. Once again, even a slow hopper will change frequencies between 100 and 200 times per second. Both the Army and the Marine Corps are moving toward digital communications. In fact, the Marine Corps Command and Control Master Plan states the following: The basic objective of Marine Corps communications is the achievement of a fully digital communications environment, to exploit the inherent advantages of digital switching and transmission techniques.7 SINCGARS-V will be employed for voice as well as data communications. The Corps' heavy reliance on tactical voice communications nets will continue. The success of a jammer against digital voice signal is related to the bit error rate (BER). The intelligibility of digital voice degrades as bit error rate increases and becomes successful when BER exceeds 10%.8 In the 30 to 88 MHz operating band of SINCGARS-V, a narrowband jammer would be able to produce an approximately 0.1% BER in the frequency hopping radio.9 To be successful in achieving an effective level of jamming, hundreds of spot jammers, operating as a system, would have to be distributed throughout the battlefield. Such a system would be difficult to control and tactically unrealistic. A variety of sources have concluded that the narrowband jammer, while useful against present single-channel radios, is not a credible threat against a frequency hopper. Barrage jammers still constitute a significant threat to tactical communications. By jamming across entire bands of the electromagnetic spectrum, these jammers can effectively block all the possible frequencies that could be employed by a hopping radio. Although extremely potent, there are many significant limitations imposed by their usage. When in operation, the jammers radiate an easily detectable and distinct electromagnetic signature. Because of this sign- ature and a lack of mobility, they become easily targetable, high value installations.10 From a logistical standpoint, broadband jammers consume large amount of power and are expensive to procure, operate and maintain.11 The density of barrage jammers also impacts upon their efficiency. When deployed in small numbers against a frequency hopping network, they can be defeated by deleting the jammed band from the hopset. This is easier said than done. In large numbers, these jammers can produce band saturation jamming. And, if saturation is achieved, radio communications cease. There are two schools of thought concerning the pos- sible employment of saturation jamming by the Russians. One point of view would highlight the fact that the Warsaw Pact is deploying more and more sophisticated, electronically controlled weapons systems.12 Their increased dependence on command, control and especially communications, is relative to their increased dependence on such sophisticated systems. (C3). Band saturation jamming denies the use of the affected ban to both sides, thus it is doubtful that the Soviets will sacrifice. Another point of view regarding the barrage jammer suggests that it might be employed. While it is true that the Warsaw Pact is obtaining technology, this technology only serves to complement vastly larger advantages in numbers of soldiers and weapons systems. Given their tact- ical bent to mass huge armies and to utilize straight- forward doctrine, it is conceivable that the soviets could more easily do without communications. Command and control is more vital to the smaller force. The employment of jammers by the threat is indeed a formidable obstacle to communications. There are, however, some performance loopholes associated with the narrowband and wideband equipment. It has been postulated that the Warsaw Pact will develop technology to fill gaps present in their other equipment and to counter frequency hopping technology. The transponder jammer provides such a solution. There are widely varying opinions as to how rapidly the threat can develop and field a functional transponder jammer. Regardless of the source, all seem to agree that such a system will be fielded during the life cycle of SINCGARS-V. It can reasonably be assumed that since the transponder jammer relies on speed, the sale of fast frequency hopping equipment overseas might in the end, only accelerate the Soviet Program. Industry sources have developed a hypothetical per- formance profile of the follower jammer. The transponder operates by searching the spectrum for a target signal; aligns the transmitter to the target signal frequency; and begins jamming.13 When the frequency hopper changes frequency, the jammer receiver stops and the spectrum is scanned once again. The race between the frequency hopping radio and the transponder occurs in microseconds. Time required for the jammer to locate a signal, adjust and begin jamming is referred to as "jammer response time".14 This response time must be short enough to allow the jammer to jam the target receiver for a portion of the time it is on an identified frequency before the receiver can hop to a new frequency. To be effective, the signal from the jammer must overlap the dwell time of the target radio by a minimum of 20%.15 There are other factors which influence the success of either the transponder or the frequency hopping radio. These will be analyzed in the succeeding section of this report. FREQUENCY HOPPING VS THE THREAT Comparisons of the performance of frequency hopping technology against the transponder jammer can only be done from a theoretical perspective. Unclassified government reports were not available on this subject, however, technical journals have addressed predicted performance comparisons. As stated previously, much of this informa- tion is prepared by industry sources and reflects the competition between companies producing both fast and slow/medium hopping radio systems. Mr. P.E. Van, an Advanced Programs Manager for Rockwell International, provided an indepth analysis of performance against the transponder jammer.16 It should be noted that Rockwell Collins is the sole U.S. producer of fast hopping equipment. Nevertheless, his arguments appear theoretically sound and worthy of analysis. It is necessary to predict the frequency response time of a transponder jammer. From what is known about Soviet technology and U.S. technology, the jammer response time is assumed to be less than 100 microseconds.17 The success of such a jammer against a frequency hopping radio is affected by the dwell time of the hopping radio, the response time of the jammer, and the signal propagation time. The signal propagation time is governed by the length of the transmission path and therefore is directly affected by battlefield geometry.18 PROJECTED USAGE The battlefield of the future will be extremely complex from a communications standpoint. Also, there are a great many uncertainties pertaining to saturation and interference produced by friendly as well as enemy equipment. Acknowledg- ing that electronic chaos may pervail, Mr. Van has limited his comparisons to the level of one frequency hopping net against a single transponder jammer. Of the three para- meters identified previously, only battlefield geometry cannot be controlled by equipment designers. The jammer response time will be determined by threat engineers, while the dwell time of the frequency hopping radio will be selected by the equipment buyer. Of these factors, the dwell time is the predominant issue because there are choices available now, before frequency hopping equipment is provided. To continue with Mr. Van's theoretical comparison, it is first necessary to describe a basic tactical radio net and make some assumptions regarding the transponder jammer. Figure 2 is Mr. Van's idea of what a tactical net will consist of. The hypothetical net approximates a net at the bat- talion or company level. The four radios on the net form a total of six links as indicated on the figured. The initial jamming position has been placed approximately 3 kilometers from the Forward Edge of the Battle Area (FEBA). It is necessary at this point in the evaluation that the jammer possess sufficient power to successfully jam a frequency hopping radio provided that it is fast enough to follow the hopset. Given the predicted jammer response time of 100 microseconds and assumed power output high enough to actually jam, it is now possible to evaluate both fast and slow/medium hopping radios against the transponder.19 As there is no published distinction between a slow and medium hopping radio, the two are considered as slow in this evaluation. It is also necessary to reiterate that the theoretical response time of the jammer is the dominant factor in analyzing frequency hopset performance. As the Soviets do not now possess a transponder jammer, there is no intelligence information regarding its response time. The point to remember in objectively reviewing the Rockwell-Collins comparison is that any jammer which can intercept and overlap the dwell time of a frequency hopper will degrade its performance. By choosing a relatively slow follower jammer, it will naturally affect a slow hopping radio to a far greater extent than a fast hopping radio. A fast follower jammer will severely degrade a slow hopping radio and probably have a less severe effect on a fast hopping radio. Whatever the situation, the slow hopping radio will be the most vulnerable. To review once again, for the purposes of comparison, the jammer response time is 100 microseconds or less, the fast hopping radio has a hoprate of 4,000 hops per second with a dwell time of 125 microseconds, and the slow hopping radio has a hoprate of 100 hops per second with a dwell time of 4,500 microseconds.20 Although these hoprates do not exactly represent production models, they approximate the ITT SINCGARS-V (slow) and Rockwell-Collins (fast) prototype. Battlefield geometry has an impact on the propagation time. While the speed of a radio transmission is constant, (the speed of light) the distance it must travel determines the time required to make a transmission. In practical terms, it takes twice as long for a radio transmission to travel two miies than it does to travel one. Propagation time becomes important because of its affect upon the frequency response time of a jammer. The performance of the jammer in overlapping the target signal is reduced because of the propagation time. The further a jammer is from its target, the longer the propagation time and, thus, the overlap with the target signal will decrease. This will decrease jammer effectiveness. In Mr. Van's analysis, he converted the propagation time to an equivalent distance factor measured in meters. Reducing this further, from seconds to microseconds, the equivalent becomes 1m second - 300m.21 An electronic signal travels 300 meters in one microsecond. Mr. Van employed this distance factor in constructing ellipses for each link of the net with the receivers and transmitters being the focus of the ellipses. Each ellipse reflects the time and distance factors which will permit jamming dependent on the jammer response time and the speed of the frequency hopping radio. The jammer must be within the ellipse to cause any jamming of the target signal.22 Once again, for the purpose of digital voice communications, 20% jamming will have a serious effect on the ability to com- municate. For instructional purposes, figures 1 through 9 have been extracted from Mr. Van's article and incorpor- ated in this report. His findings regarding fast hopping performance are as follows: * The jammer must move to a position very close to the net in order to cause any jamming on all links. * The jammer could successfully jam three links if it were co-located with one of the trans- ceivers - a very unlikely condition. * The jammer could successfully jam two links if located at the intersection of X1 - X3 and X2 - X4... also unlikely, but in this case, communications could be relayed around the jammer on the other links. * There is no location where the jammer could successfully jam more than 50% of the links in this net. * With the net and jammer locations shown in Figure 2, none of the links in this fast hop net are successfully jammed even though the jammer is very close (3km) to the net and the jammer response time (100 microseconds) is very short.23 His findings regarding slow hopping performance are as follows: * The transponder jammer jams all slow hop links in excess of 97%. Click here to view image * The transponder jammer could move hundreds of kilometers behind the Forward Edge of the Battle Area and still cause 20% jamming of all slow hop links. * In order to make the slow hop performance equal to that of the fast hop in this net geometry, it is necessary to increase jammer response time from 100 microseconds to 3,600 microseconds. * An effective jammer against slow hop can be fielded in the next couple of years. Clearly, slow frequency hopping systems, cannot evade the kind of jammer projected for introduction during the life of the new combat net radio.24 What conclusions can be drawn from this analysis? First, there is a need to reevaluate the criteria which prompted the U.S. Army to proceed with development of a slow hopping system. There are a number of factors which could be included such as cost, flexibility, simplicity and other operational requirement specifications. However, if the essential criterion for selection was ECCM perfor- mance against the transponder jammer, then the decision itself should be evaluated. There is a need to devote further study to the Warsaw Pact's ability to produce a transponder jammer. There is a need to "what if" any possible development. The U.S. Army would very likely face the transponder jammer in an area such as Central Europe. The Marine Corps is much less certain to meet such a threat. Research should be performed to determine if the SINCGARS-V is suited to the diverse Marine Corps missions. Low intensity conflict may not require the transponder jammer. The Marine Corps is attempting to grapple with the tremendous advances in electronics. The management of change brings new challenges which complicate the traditional procurement cycle. The Marine Corps Command and Control Master Plan was published in 1983 as an attempt to con- solidate all developments in the command and control area.25 The approach utilized in the Master Plan presented descip- tions of equipment under development and diagramed snap- shots of communications schemes using the new equipment in a number of timeframes. This approach to planning has been criticized for reliance on equipment capabilities rather than on present and future requirements that new equipment must support.26 There are arguments to support both viewpoints. However, what must be remembered is that any snapshot of a future communications scenario can be radically altered by technology at any time. Despite this criticism, the Master Plan is one of the few documents which has considered procurement and employment information regarding SINCGARS-V. Long before the publication of the Command and Control Master Plan, the 1976 Joint Operational Requirement was produced.27 Validated by the Joint Chiefs, it contained a Required Operational Capability (ROC) that the Army had forwarded. The ROC outlined the need to develop specifi- cations for a new family of VHF/FM single channel tactical radios. Some of the more significant statements extracted from the ROC are as follows: * The system must operate in a manner which does not discernibly degrade the communications capabilities of the radio set or its electro- magnetic environment. * An ECCM capability will be available as a module for priority users as an application to the basic radio. * The operational and organizationsl concept described for the Army is applicable for the Marine Corps. * A retransmission/repeater capability for ground and airborne configurations must be provided. * An ECCM module attachable to the basic radio for selected/designated users and which can defeat the enemy's projected threat and continue to operate is an essential charac- teristic. * Maximum advantage will be taken of previous developmental work to insure the acquisition of the latest state-of-the-art military radio.28 Between the Publishing of the ROC in 1975 and the com- pletion of the Marine Corps Command and Control Master Plan in 1983, the Marine Corps had published a number of policy statements which were subsequently included in the intro- duction of the Master Plan. There are several statements which impact upon the SINCGARS-V program. They are as follows: * System communications requirements will be met by the Landing Force Integrated Commun ications system (LFICS) which will provide the telecommunications required for the transfer of information in digital and in analog form. * The effects of Electronic Warfare (EW) will be considered when acquiring tactical tele- communications equipment. Systems will be capable of operating in a high ECM threat environment. * Requirements for operator and/or support personnel and requirements for personnel of higher mental groups must be identified and provided for as early as possible in the developmental process. * Marine Corps requirements for new acquisi- tions will be satisfied, whenever suitable and acceptable, through the programs of other services and governments agencies, or through joint development efforts. * C4 system specifications will require that the equipment be designated to operate in any area of the world to which Fleet Marine Forces may be deployed.29 The stated objective of Marine Corps communication is an achievement of a fully digital communications environment to exploit inherent advantages of digital switching and transmission techniques.30 The radio development concept associated with this objective calls for VHF radios based on 25 KHz channel spacing and 16 Kbps data rates. Such equipment must be capable of both voice and data inputs. From a tatical perspective, the 25 KHz channelization permits usage with present single channel VHF radios and permits a phasing in of the digital equipment. Single channel radios will continue to carry a heavy communications load despite the doctrinal shift to multichannel radio systems. The radios will remain the mainstays of communi- cations at the squadron and battalion levels.34 Additionally, the SINCGARS-V and other single channel sets will be relied upon extensively during the initial stages of amphibious operations as well as those situations where terrain, mobility, and other circumstances preclude the use of multichannel. SINCGARS-V first appears in the Master Plan in the LFICS projection for the period of 1987-1990. In the pro- jection, SINCGARS-V is to replace the AN/PRC-77, the AN/VRC-12 series and the AN/GRC-160.32 Most of the equipment to be replaced is approximately 20 years old and features dated technology. The basic SINCGARS-V radio provides a capable and attractive alternative to this outdated equipment. In addition to the single channel and ECCM roles, SINCGARS-V will also provide a capable backup for data transmission should multichannel communications become a casualty from either battle damage or ECM. SINCGARS-V also has the capability to transmit facsimile and teletype traffic. Its purported 16Kbps data transmission rate would make it useful at all levels for data traffic. In reviewing the Master Plan's 1991 summary of telecom- munications to support major command, control and supporting systems data transfer, it becomes apparent that SINCGARS-V will not only provide a backup for multichannel but will also provide key transmission links for Digital Communi- cations Terminal (CT), the Marine Intergrated Fire and Air Support System (MIFASS) and the Tactical Combat Operations (TCO) system.33 Not all of these applications have proven successful to date, however, these apparent deficiencies will be discussed later in this report. SINCGARS-V will not only be the primary means of tactical voice, it permeates both voice and data systems throught the Marine Amphibious Force (MAF) level. At the infantry battalion, artillery battalion, artillery battery and squadron levels, the only ECCM-protected data trans- mission capability will be provided by SINCGARS-V. The Master Plan reiterates that the employment of VHF multi- channel or single channel radios for this purpose proves unsatisfactory in terms of surviviability. The need to be constantly on the move makes time consuming antenna remoting more difficult and increases the probability of enemy intercept, jamming, and artillery attack. This concept is suspect as operational tests of the SINCGARS-V have demonstrated a need to remote antennas to avoid friendly interference. Distribution of SINCGARS-V to the Fleet Marine Forces is a key issue. Operationally, the employment of SINCGARS-V as a replacement for the PRC-77, VRC-12 and GRC-160 poses no significant difficulties. There are some range limita- tions with SINCGARS-V because it is a digital radio. However, it does provide greater channel selection with its 25KHz channel spacing; it is close to the state-of-the-art; and, when operated as a single channel tactical radio, it is relatively easy to operate with self-diagnostics to assist in trouble-shooting. Although SINCGARS-V is a suitable replacement radio, it is an extremely expensive replacement. Cost estimates vary widely. However, the minimum estimated costs for SINCGARS-V are eight times the cost of the present equipment. The maximum estimates are approximately double the minimum. Distribution of SINCGARS-V as a frequency hopping radio with its ECCM capability is a complex business. Because of friendly interference generated by frequency hoppers, restrictions on mobility because of required antenna remoting, and its employment for data transmission, there are only certain nets SINCGARS-V can be used for and only at certain levels of command. There is also a need to vary any employ- ment matrix which could be developed to prevent creating a very distinguishable electromagnetic signature. The integration of SINCGARS-V into LFICS poses other deficiencies which require further study. Operational testing has demonstrated that the Digital Communications Terminal will not interface with SINCGARS-V for data traffic. Difficulties in resolving this problem suggest the SINCGARS-V may not be able to perform its prime function in the LFICS architecture. FREQUENCY MANAGEMENT Management of the electromagnetic spectrum is a global concern. The phenomenal spread of communications technology and the demand for this technology by all other nations has greatly increased competition for the limited radio fre- quencies available. Unrestricted use of the spectrum by any country, corporation, or organization can severely impact upon the ordered use of the spectrum of others. Spectrum management cuts across commercial, governmental, and military lines. Even within the United States, there is intense competition between these sectors. The balance now existing is indeed fragile. Military communications constitute only a portion of a much broader international communications scheme. Under peacetime conditions, the use of the electromagnetic spectrum is somewhat controlled. The military employs only a portion of the spectrum for operations and training. There is a great deal of speculation regarding military use of the spectrum during general or limited warfare. When comtemplating this issue, it is necessary to recognize that, despite the intensity of military operations, there is still a requirement for non-military communications. Another factor to consider is competition within military forces for the portion of the spectrum allotted to such. This is particularly true within the United States Armed Forces. All branches of the military require radio frequencies to exercise command and control. There is a common technology producing service interference. An example of this would be the doctrinal use of VHF/FM radios for tactical ground communications by both the Army and the Marine Corps. To take this a bit further, there is poten- tial saturation of the spectrum by a given service on any battlefield. This potential exists because of the prolif- eration of command, control and communications systems. The intentional saturation of the spectrum or a portion of the spectrum by the use of Electonic Warfare greatly com- plicates modern battlefield communications. To summarize, frequency management on the modern battlefield cannot be done in a vacuum. A frequency manager must consider potential interference created by organic equipment, interference from a commercial or governmental use of the specturm, as well as the reverse; and the impact that communications operation may have on host country or international communications. SINCGARS-V and, in fact, all frequency hopping radios add a new dimension to frequency management. Operations in frequency hopping modes defies the relatively organized idea of frequency management. Because frequency hoppers operate on a number of frequencies in a random pattern with respect to time, it has become virtually impossible to "neatly organize" the frequency scheme. SINCGARS-V when operating in the frequency hopping mode, can use up to 2,320 channels.34 The enormous number of variables introduced to frequency management by the employment of such radios on an already congested battlefield spectrum necessitated further study. The U.S. Army, agent for the SINCGARS-V Program, requested that the Electromagnetic Compatability Analysis Center (ECAC) assist in the development of procedures to reflect the frequency management requirements for the SINCGARS-V radio.35 The results of the ECAC study were published in a report entitled DRAFT SINCGARS FREQUENCY MANAGEMENT PROCEDURES which was published in October of 1984. The approach of the ECAC report was centered around the unique requirements of SINCGARS-V and were summarized as follows: Significant changes will be the management of multiple frequencies in one radio versus the current management of only a single frequency in a radio, as well as the auto- matic loading of multiple frequencies and variables into the radio through the use of computers...a method that cannot be accomplished by the operator manually. The total number of variables used for secure operation of the radio nets across the entire battlefield poses unique distribution problems for the battlefield spectrum managers.36 The addition of the frequency hopping radio adds a requirement for an automated or computerized system to sort out communications variables; to ensure electromagnetic compatability; and to reduce self-generated interference. The U.S. Army produced a Required Operational Capability for what is now referred to as the Battlefield Electronics Communications - Electronics Operating Instructions system (BECS). In addition to handling the SINCGARS-V unique requirements, BECS was to be capable of generating, process- ing, displaying, printing, and storing information for HF, VHF/FM and UHF radio bands. The BECS functions regarding SINCGARS-V were directed toward frequency resource files, Communications-Electronics Operating Instructions (CEOI) information, frequency assign- ments, transmission security (TRANSEC) keys, and hopset data. The BECS provided a means to electronically distribute this information from the planners down to the SINCGARS-V users.37 To plan the frequency management procedures to support SINCGARS-V, ECAC began by analyzing the number of frequencies available for inclusion in the hopset of the radio. It is recognized that in the operating band of SINCGARS-V (30-87.975 MHz), there is competition for the spectrum from commercial radio sources. In view of this, a general assumption has been adopted to provide the commercial operations protection. The frequency resource within the operating band is decreased each time a protected frequency is added. The frequency resource then forms a pool from which a hopset for SINCGARS-V can be extracted. During the development of SINCGARS-V, a decision was made to employ a universal hopset. This means that under optimum conditions all 2320 channels can be incorporated in the hopset.38 By employing the universal hopset, it theoretically provides the greatest ECM protection because the transmission can vary over a wider range within the band. As stated earlier, there are some frequencies which must be protected. SINCGARS-V has the capability to delete or lockout these frequencies from the universal hopset. These lockouts are not necessarily limited to civilian frequencies. There are certain military frequencies which require protection based on priority use, and possible interference with adjacent or supporting units, or the type of communications circuit involved. The number of lockouts has a direct effect on the ECCM effectiveness of SINCGARS-V. Any reduction in the frequency resource produces a reduction in the number of frequencies available for the hopset. The more limited the hopset, the greater the probability of intercept and jamming. Critics of SINCGARS-V cite this as a significant deficiency. The heavy world-wide use of the electromagnetic spectrum in the VHF band produces many frequencies which fit the general criteria for a lockout. The continued growth of national and international communi- cations circuits as well as the military's increasing sat- uration of the band will bring about even more restrictions on the universal hopset. Conceptually, this restriction would also increase the probability of interference between SINCGARS-V radios. Interference, whether generated by friendly equipment or enemy ECM activity, has the same detrimental effect. Critics of SINCGARS-V have concluded that realistic lock- outs on the universal hopset could narrow the hopset to such a degree that the radio would be very vulnerable to a narrowband jammer. Peacetime restrictions on the hopset may also effectively preclude realistic operator training. Proponents of SINCGARS-V predict many of the restric- tions on the universal hopset may be lifted when hostilities commence. Should this not occur, there are other alterna- tives such as reducing transmitter power output, the use of directional antennas, and the limiting of the use of the universal hopset to a selected number of high priority circuits. The October 1984 ECAC report highlighted two other areas of practical significance. These areas are cosite interference and retransmission.39 To begin, cosite interference is electomagnetic interference produced by radios operating in proximity to each other, as would be the case in a command vehicle or command post. Because of the broad utilization of the VHF band by SINCGARS-V, there is the possibility that potentially severe electromagnetic interference may develop as the density of such radios at a site increases.40 Cosite interference adds a new dimen- sion to communications planning. Under combat conditions it may take considerably longer to determine if enemy jamming is occurring. In fact, jamming may be the least difficult to solve when compared to having to analyze which of several radios that are using hundreds of fre- quencies may be producing the particular interference. To solve the cosite interference problem, ECAC recom- mended use of minimum radio output power; physical separa- tion of the antennas; and antenna remoting.41 Each of these recommended courses has an impact on battlefield tactics. The use of reduced power output brings with it a corresponding reduction in the range of the radio. Decreases in range necessitate moving tactical headquarters closer together or employing longer ranges, yielding less ECM resistant forms of communications. Remoting is employed with present single channel equipment to reduce interference and to change the electro- magnetic signature of headquarters. Remoting is a sound communications practice. However, it is not without draw- backs. Remoting takes time; decreases a unit's ability to displace; and expands the security perimeter of a head- quarters. Central to this issue is how far the antennas of frequency hoppers must be separated to reduce interference. The potential exists that the use of SINCGARS-V may neces- sitate the expansion of the headquarters area with the resultant expansion of the security perimeter. At the same time, headquarters must be brought closer together because of the range restrictions produced by low power output. Cositing interference also affects the use of SINCGARS-V radios at a retransmission site. The interference problems are identical to those just discussed, however, they are intensified because of the physical and technical confines of a retransmission site. As force mobility is enhanced so is the probability that rapidly advancing forces may out-distance their own communications. The speed of helicopters (JVX) coupled with unfavorable terrain, force some communications trade-offs. These trade-offs are also affected by the reduced range of the SINCGARS-V. To sustain communications with a quickly advancing unit, it is necessary to employ retransmission sites or to use high frequency communications. HF communications do not provide the ECCM protection or the flexibility of SINCGARS-V. Using the frequency hopper as a single-channel retrans- mission site to avoid cosite interference and operator problems, also significantly reduces ECCM protection. Un- favorable terrain may also preclude HF communications. Because of the potenetially severe interference problems at a frequency hopping retransmission site, ECAC has strongly recommended further testing.42 CAPABILITIES The Required Operational Capability statement regarding SINCGARS-V contained a number of broad statements directed at what the radio should be capable of doing. Prominent among these required capabilities were a need for more usable channels; a reduction in the operator burden caused by weight, size and operational complexity; and the capabil- ity for secure voice/data operation in a manner which did not discernibly degrade the communications capabilities of the radio set or its electromagnetic environment.43 Also included were reductions in maintenance requirements and life cycle costs, and improved equipment reliability and availability. The threat statement contained in the ROC did not specifically address potential development of the transponder jammer. The Defense Intelligence Agency publications which provided the basis for the threat description jammer. The threat statement changed substantially after the development process had begun. The essential characteristics portion of the ROC included sixteen general concerns with the most noteworthy being the requirement for a ground and air retransmission/ repeater capability; an ECCM module which could defeat the enemy's projected threat; and the compatability with other systems under development.44 The ROC also included a proposed distribution scheme however, that was also overcome by events. Between 1975, when the ROC was generated, and 1984, when the ECAC testing was accomplished, the capabilities of the radio were extensively refined. The SINCGARS-V now provides the following capabilities: 1. Voice 2. Data 3. Communications security (COMSEC) compatible 4. ECCM (frequency hopping) operation 5. Single channel operation 6. 2320 channels (25KHz channelization) 7. Remotable 8. Interoperates with current series of VHF-FM radios on 50KHz channels 9. Six channel presets plus cueing frequency 10. Built in test (BIT) - self diagnostic 11. Channel scanning (single channel only) 12. Frequency offsetting (single channel only)45 The original design concept for SINCGARS-V differed from previous radio procurement programs. SINCGARS-V included the development of the basic radio, its communica- tions security device, and its electronic counter-counter- measures device. This program attempted to integrate development in all three areas from the inception. Pre- viously, such devices were developed separately, normally by different contractors. Commercial literature prepared by the Aerospace/ Optical Division of ITT (SINCGARS-V contractor) highlights a number of areas which the contractor endorses as user benefits.46 Operational simplicity was a requirement stated directly in the ROC. ITT feels it has satisfied this requirement in a number of ways. To begin, SINCGARS-V is a very flexible radio system. It can be employed for voice or data, unencrypted and encrypted text, and it can be remoted.47 Further flexibility is added by its capability to handle facsimile, teletype, and digital message devices. There are also features designed to simplify the operator's tasks. Switching from the single channel mode to ECCM fre- quency hopping mode is done with a single switch. All of the communications variables can be established in all radios in a given net via a radio frequency link to all stations on the net. This eliminates the need to physically transport and load these variables to establish reliable communications. The keyboard located on the transceiver pemits the operator to check the status of the ECCM module, the data module, the battery status, and other technical performance factors. The built in test (BIT) provides fault isolation to subsystem component level.48 The operation of frequency hopping radios requires that they remain synchronized with other stations on the net. To ensure that all stations maintain the correct Mission Day (MD) (calendar day) and Time of Day (TOD), the Net Control station coordinates the first installation. However, from then on this information is updated electron- ically every time the Net Control Station communicates with another net station. In this manner, synchronized is assured. As discussed previously, SINCGARS-V and its primary ancillary devices were developed together. Because of this modular approach, it is much simpler to tailor the radio set to best suit its mode of operation. The compactness of the radio set is also perserved. ITT's frequency hopping scheme in the SINCGARS-V utilizes full band hopping. In this matter, 2320 separate channels are created using 25 KHz channels. By employing the full band, it becomes considerably more difficult for an enemy to successfully defeat SINCGARS-V using a wide- band or narrow-band jammer. The contractor also contends that full band hopping simplifies frequency management and permits positive control over electromagnetic interference. LIMITATIONS It is necessary to analyze the capabilities and performance of a new system of technology in an objective, systematic manner. The systems acquisition process of the Department of Defense provides such a screening process. Beginning with the submission of a Required Operational Capability statement, a new requirement is scrutinized to determine its validity. The mechanism to accomplish systems validation within the Department of Defense, is the Defense systems Acquisition Review Council. The Marine Corps has established an internal review process culminating in a Required Operational Capability approved or disapproved by the Marine Corps systems Acquisition Review Committee. The operational deficiency, operational concept, essential characteristics, technical assessment and cost assessment sections of the Required Operational Capability provide the acquiring agent and the defense industry with specific guidance. Acquiring agent for SINCGARS-V is the U.S. Army. Marine Corps interest in the project is rep- resented by project officers at Headquarters, United States Marine Corps and at the Development Center, Marine Corps Development and Education Center, Quantico, Virginia. During the course of preparing research for this report, a number of individuals now associated with, or previously associated with SINCGARS-V were interviewed. These interviews produced information favorable to SINCGARS-V, as well as a great deal of criticism about the system and its procurement history. Having discussed capabilities of SINCGARS-V is the previous chapter, it is appropriate to take a critical look at the radio. The primary concern in evaluating any tactical system is performance against threat. An ancillary factor is what the future threat will be. The threat likely to exist during the life cycle of a new system must be explored. Comparison against the present threat is a finite matter. However, the future threat is not easily determined. In evaluating SINCGARS-V, this issue becomes even more complex because there are significant factors affecting performance against both the present and future threats. There is a consensus among those interviewed and the technical journals that the future threat to frequency hopping tactical radio nets is the transponder jammer. There is disagreement regarding just when the Soviet Union will become capable of developing such equipment. Beyond this, there is considerable contractor squabbling regarding just when the Soviets will perfect a transponder to effectively target emerging radio systems. Regardless, most sources are highly confident that the transponder jammer will be fielded during the operational life of SINCGARS-V. At issue is not only the performance of the slow- hopping SINCGARS-V, but frequency hopping in general as an effective Electronic Counter-Countermeasure. Assuming that the Soviets would target the SINCGARS-V initially, it is also reasonable to assume that they could quickly expand such technology to target fast hopping radio systems. This raises a broader question concerning whether the increased costs and complexity associated with the frequency hopping technology provide an acceptable trade-off for limited protection against the threat. Aside from the Rockwell- Collins article discussed earlier in this report, almost all of the limitations associated with SINCGARS-V apply to frequency hopping radios in general, regardless of the hoprate. Because of the probable development of the trans- ponder jammer, SINCGARS-V performance as an ECCM resistant systemis questionable. It is necessary to remember that SINCGARS-V was developed to satisfy a number of needs just one of which was the ability to withstand the degrada- tion produced by enemy Electronic Warfare operations. A related problem is the performance of SINCGARS-V against the current Soviet wide band and narrow band jammers. There is a basic issue invloved in this matter. At present, there is no universally accepted plan for the use of the electromagnetic spectrum under wartime conditions. This situation exists because the electromagnetic spectrum will become a part of the battlefield of the future. Nonetheless, the most efficient way to begin examining such a conflict is to start with the constraints imposed on the battlefield by our own systems and doctrine. As it is unlikely that United States involvement in a conflict will be unilateral, it is also necessary to consider the re- quirements of allied military forces and government agencies. The VHF-FM band is heavily congested across the globe. This situation is likely to become worse as command and control systems proliferate in both military and civilian sectors. Other considerations are the intensity of the conflict and the battle geography. In a low intensity conflict or insurgency, the United States, as well as our allies may very much want to preserve and not interfere with the existent national communications system. In such a conflict, the use of means of communications for other than military purposes may, in fact, promote or expedite the successful conclusion of hostilities. In high intensity conflict, particularly with the Soviet Union, any attempt to control the electromagnetic. spectrum may prove unsuccessful. Reliance on very inflex- bile doctrine and the very high probability means they will seize the initiative and commence hostilities under condi- tions which are favorable to them and provide them with the opportunity to prepare detailed plans to defeat or degrade any Western capability. The Soviets can develop tactical schemes which do not require the complex command and control that is so vital to American and Western forces. There is a very real possibility that barrage wide-band jamming will be employed in any direct conflict with the Soviet Union. Under such conditions, the cost effective Electronic Counter-Countermeasure available may be an aircraft with anti-radiation missiles or an artillery barrage. Frequency hopping is not a defense against barrage jamming. Despite claims to the contrary, SINCGARS-V is probably the most complex tactical radio yet developed. In all fairness to the Army and the International Telephone and Telegraph Company, who would both dispute this statement, the following justification is provided. There is some conditional validity to the contractor claim that SINCGARS-V is a simple radio to operate. The conditions required to make this true are that all functions on all SINCGARS-V net stations are fully operable, that Net Control Station operators are thoroughly aware of radio capabilities and that imaginative frequency management has produced very little electromagnetic interference. The Net Control Station operator is the vital link in the SINCGARS-V tactical radio plan. His or her tasking includes the responsibility for establishing, maintaining, and controlling the radio net in a potentially hostile Electronic Warfare environment.49 The Electromagnetic Compatibility Center's study regarding draft SINCGARS-V procedures included the following statement regarding the Net Control Station operator: Because of the inherent complexity of the frequency hopping radios, additional operational and management responsibilities have been delegated to the NCS operator. As a result of increased demands placed on the SINCGARS-V NCS operator, additional training and additional qualifications will be required.50 The Net Control Station operator on a Marine tactical radio net would typically be a Corporal or a Lance Corporal. To better match the Marine and his responsibilities, it is necessary to identify his functions on a SINCGARS-V net. These responsibilities would include: * insuring effective utilization of the frequency resource provided for net operation in accordance with the unit standing opera- ting procedure (SOP) * net controlling * directing net start-up using Electronic Remote Fill procedures * using only the minimum power required to communicate * answering cues * maintaining communications discipline * directing single-channel operations * controlling late net entry requests * insuring that net members have the correct CEOI/SINCGARS-V variables in their Electronic Notebooks * establishing and maintaining the net TOD51 The management of Communications Electronic Operating Instructions and SINCGARS-V variables includes the correct usage of the net transmission security key, the hopset, the net identification, the Electronic Remote Fill Frequency, the cueing frequency and finally, the Mission Day/Time of Day.52 The typical net station radio operator within a Marine tactical radio net is a Private First Class. Depending upon the tactical situation and unit involved, the radio operator may or may not be a communicator by occupa- tional speciality. The SINCGARS-V radio operator does not have as many management responsibilities as the Net Control Station operator, however, he is directly responsible for properly using the SINCGARS-V variables, being aware of the net identification assignments and following the instructions of the Net Control Station.53 From a practical standpoint, radio operators employing SINCGARS-V will be responsible for many more functions than with present equipment. The brief descriptions just provided do not encompass the operating responsibilities and trouble- shooting procedures required in the event SINCGARS-V is used as a transmission means with another C4 systems such as the Digital Communications Terminal. Testing operating procedures such as those described above in a test bed or controlled environment may, in fact, demonstrate that radio operators of average capabilities are capable of operating a SINCGARS-V radio net. However, employing the radio under field or tactical circumstances may prove the opposite. The following questions are certain to arise: * Is it prudent to assume that the operator has the ability to perform frequency management and to recognize and control electromagnetic interference? * Is it reasonable to assume that the average radio operator can manage six communications variables under field or combat conditions? * Should communications be disrupted, how long will it take a radio operator to troubleshoot and reestablish communications under tactical conditions? * If interference is being generated by enemy Electronic Countermeasures, another SINCGARS-V station, or other colocated equipment, will the radio operator be able to isolate the source? From a higher level perspective, another SINCGARS-V variable has been added to the previous list: operator proficiency. There has been a great deal of testing done with the SINCGARS-V radio system. Appendix A of the October 1984 Electromagnetic Compatability Analysis Center report pro- vides summaries of twenty-four projects and reports.54 These reports vary in their security classifications, many of which could not be incorporated into this paper for security reasons. Informal, unofficial information con- cerning the testing process was furnished by individuals who are directly involved with SINCGARS-V development. Several of these individuals expressed a concern that sufficient testing would not be completed prior to testing the radio. This suspicion followed relatively poor performance of the radio during manufacturer's demonstrations. In addition, the unusually long testing cycle had been stretched to coincide with the fielding date of the equipment. A great deal of testing has been done on a theoretical level without the use of an actual SINCGARS-V radio. Aside from the Electronic Counter-Countermeasures capability provided by frequency hopping, the single most significant operating feature is that is provides digital communications. This development adds unprecedented flex- ibility to Marine Corps communications. The conversion from analog to digital was the predominant communications objective contained in the Marine Coprs Command and Control Master Plan.55 Paralleling the development of SINCGARS-V are several other systems band technologies which will fully exploit the speed, security, and flexibility of data communications. The design objective data capacity for SINCGARS-V is 16 kilobits per second (Kbps).56 This standard assures a minimum data transmission rate to provide interoperability with other equipment developed under the TRI-TAC program. Information was obtained from sources who have stated that the manufacturer is having difficulty operating SINCGARS-V with a data transmission rate in excess of 12 Kbps. Further difficulties have appeared during testing of SINCGARS-V with the Digital Communications Terminal. One problem appears to involve hardware matching between the SINCGARS-V and the Digital Communications Terminal precluding employment in concert. This situation is analogous to other SINCGARS-V difficulties where the complexity of the system defies timely fault isolation. This leads to con- jecture that if at such a late stage in development engi- neers and project officers are encountering difficulties, what will be impact when the system is introduced to the field? All digital radio systems have limited range relative to the older analog systems that they replace. This is produced by the greater sensitivity of digital radios to signal strength and single-to-noise ratio. Once again, this is true of all digital radios, not just SINCGARS-V. One of the operational trade-offs associated with the employment of SINCGARS-V will be decreased distance between operating stations if a net or data link is to function successfully. This has an enormous tactical impact not only on smaller units, but also the positioning of higher headquarters which will require extensive data communications. It has been recognized for quite some time that the range of communications systems has not expanded to ade- quately support mobile, fast-moving operations that are rapidly becoming the rule, rather than the exception. To assist SINCGARS-V in meeting this challenge, a power amplifier has been incorporated into a long range version of the radio. It has been reported that the amplifier has been unsuccessful to date in producing any significant gains in system range. Remember also the previous discus- sions of the difficulties in cosite operation of high power SINCGARS-V radios. Range limitations also favor present threat jammers and the future transponder jammer. The evolution to "over-the-horizon" amphibious oper- ations will occur during the life cycle of the SINCGARS-V system. Given the range limitiations just discussed, one can conclude that unforseen hazards await such operations if they are, in fact, dependent on frequency hopping or digital communications. Present communications doctrine places heavy reliance on VHF-FM secure circuits to support amphibious operations. The Marine Corps Command and Control Master Plan suggests the employment of SINCGARS-V in the data mode to sustain ship-to-shore communications until multi-channel can be established ashore. This fact spawns a number of acute problems. Electromagnetic interference is an enormous problem aboard ship. In addition to the very large number of electronic emitters in the radio suite, every piece of machinery aboard produces some sort of interference. These two conditions combined, have made frequency manage- ment very difficult under the best conditions. Aboard an ambhibious ship, the situation is aggravated by the large number of ship-to-shore circuits required by the Landing Force for Command and Control purposes. Under current frequency management procedures, obtain- ing reliable communications is difficult and, often times, impossible. The massive colocation interference aboard ship makes trouble shooting an endless process. Given the simp- licity of the present single-channel concept of communications and the difficulties involved, what will occur if complex frequency hopping and data communications are added? A frequency hopping radio will add enormous complexity to the already difficult shipboard frequency management picture. If SINCGARS-V is to be part of the ship-to-shore com- munications scheme for over-the-horizon amphibious operations, there are two other significant limitations. First, the range required for such operations clearly exceeds the cap- ability of SONCGARS-V. A retransmission capability is a necessity. The potentially severe eletromagnetic interfer- ence problems associated with SINCGARS-V retransmission sites were discussed earlier. Because antennas cannot be remoted in the amphibious environment, both the receive and transmit antennas of a retransmission station must be located on a single airborne or seaborne plateform. It is probable that frequency hopping retransmission may prove impossible from an airborne platform. Electromagnetic interference produced by the SINCGARS-V radios, an aircraft's single- channel radios, and the addition of the aircraft's own Have-Quick frequency hopper may preclude any successful communications. Retransmission through a dedicated vehicle such as a Remotely Piloted Vehicle may prove im- possible because the vehicle's small size would preclude even minimal separation required for antenna systems. Additionally, the control link for the vehicle itself may not be able to withstand the electromagnetic interference that is produced. Retransmission from a seaborne platform is susceptible to the same kinds of interference problems discussed above. CONCLUSION In examining the balance between the capabilities and limitations of SINCGARS-V, it is evident that limitations now overshadow capabilities with the radio system. The existence of such crucial deficiencies so late in the development and procurement cycle should prompt a reeval- uation of the program. The Marine Corps should review the requirement which spawned the system, and act to ward off the disaster materializing. The original Required Operational Capability generated in 1975, identified a need to develop some replacement for the aging AN/PRC-77 and AN/VRC-12 series tactical communi- cations equipment. That system was to provide more usable channels as well as the ability to communicate by secure voice and data without creating excessive electromagnetic interference. Further criteria included: that the new system provide for retransmission; that the new radio be relatively simple to operate; and finally, that the system provide protection in the Electronic Warfare environment. From the beginning, SINCGARS-V has evolved into a very complex radio system. To objectively evaluate the system, it is reasonable to compare what the acquisition of SINCGARS-V provides, relative to what it was supposed to provide at its inception. As a replacement for aging equipment, SINCGARS-V is considered a success. SINCGARS-V provides an expanded number of channels, a self-diagnostic system, and boasts a more modern radio technology. It does not, however, replace some key capabilities of the older equipment. It is deficient in both operating range and retransmission capa- bility. SINCGARS-V can successfully provide secure voice communications and yields, at present, a slightly degraded data transmission capability. Its success in performing these functions without producing excessive electromagnetic interference is largely dependent upon its operation in a single-channel mode. There are several problems associated with the operation of SINCGARS-V as a frequency hopping system. The perform- ance of SINCGARS-V in this ECM resistant mode is adversely affected by the potential development of a near term threat transponder jammer; the limited frequency spectrum which may be utilized; and the serious electromagnetic interference generated by architecture limitations. The operational simplicity of SINCGARS-V is a moot point. Proponents of the system argue that simplicity has been built into the system and that, to some degree, the radio is easier to operate because of its self-diagnostic device and its ability to use Electronic Remote Fill to electronically update variables in net station radios. Critics of the system contend that, given the numerous other deficiencies of SINCGARS-V and the greatly expanded number of variables required for operation, the radio exceeds the operational and troubleshooting skills of an average radio operator. There is a great deal of pessimism afoot. SINCGARS-V is not so hot. The expressed frustration and doubt about the radio wears the frown of fatalism. Is the system going to be force-fed regardless of the hazards forseen? While it is easy to generalize and categorically recommend that SINCGARS-V not be procured, it is obvious that the situation is not that simple. Instead of writing doctrine to support equipment, there is a need to identify a communication doctrine requirement and then develop equipment to support it. SINCGARS-V may in fact satisfy some doctrinal requirements and not others. A complete reevaluation of the program is in the best interests of the United States Marine Corps. FOOTNOTES 1. P.E. Van, "New Concepts in Battlefield Communications Part 1 - fast frequency hopping", International Defense Review, March 1982, p. 327. 2. Ibid., p. 329. 3. Ibid., p. 327. 4. G.S. Sundaran, "New Concepts in Battlefield Communi- cations Part 2 - slow/medium frequency hopping", International Defense Review, May 1982, p. 562. 5. Ibid., pp. 562-563. 6. Van, "New Concepts in Battlefield Communications Part 1 - fast frequency hopping," p. 328. 7. United States Marine Corps Command and Control Master Plan, Headquarters U.S. Marine Corps, March 1983, p.5-3. 8. Van, "New Concpets," p. 328. 9. Ibid., p. 328. 10. Ibid., p. 328. 11. Ibid., p. 328. 12. Ibid., p. 328. 13. Ibid., p. 328. 14. Ibid., p. 328. 15. Ibid., p. 328. 16. Ibid., pp. 327-330. 17. Ibid., p. 329. 18. Ibid., p. 329. 19. Ibid., p. 329. 20. Ibid., p. 329. 21. Ibid., p. 329. 22. Ibid., p. 329. 23. Ibid., p. 330. 24. Ibid., p. 330. 25. Command and Control Master Plan 26. S.L. Pipho, point paper prepared for the USMC Development Center, September, 1984, "A Development Strategy for a LFICS/C4I Architecture". 27. Joint Chiefs of Staff, memorandum to the Secretary of Defense, 26 March 1976, "Joint Operational Requirement for a Family of VHF/Frequency Modulated Single Channel Tactical Radios, " JCSM - 110-76. 28. Ibid. 29. United States Marine Corps Command and Control Master Plan, Headquarters U.S. Marine Corps, March 1983, p.1-4. 30. Ibid., p. 5-3. 31. Ibid., p. 5-2. 32. Ibid., Appendix D. 33. Ibid., Appendix D. 34. Electromagnetic Compatability Analysis Center, Draft SINCGARS-V Frequency Management Procedures, study prepared for the U.S. Army Signal Center by Troy N. Allen and Lawrence L. O'Neill, October 1984, p. 2-1. 35. Ibid., p. 1-1. 36. Ibid., p. 1-2. 37. Ibid., p. 2-4. 38. Ibid., p. 3-1. 39. Ibid., p. 6-2. 40. Ibid., p. 6-2. 41. Ibid., p. 6-1. 42. Ibid., p. 6-2. 43. Joint Chiefs of Staff, memorandum to the Secretary of Defense, 26 March 1976, "Joint Operational Requirement for a Family of VHF/Frequency Modulated single Channel Tactical Radios", JCSM-110-76. 44. Ibid. 45. ITT Aerospace/Optical Division, commercial circular, "SINCGARS-V, the Voice of C3I". 46. Ibid. 47. Ibid. 48. Ibid. 49. Electromagnetic Compatability Analysis Center, Draft SINCGARS-V Frequency Management Procedures, study prepared for the U.S. Army Signal Center by Troy N. Allen and Lawrence L. O'Neill, October 1984, p. 2-1. 50. Ibid., p. 5-9. 51. Ibid., p. 5-10. 52. Ibid., p. 5-11. 53. Ibid., p. 5-13. 54. Ibid., Appendix A. 55. United States Marine Corps Command and Control Master Plan, Headquarters U.S. Marine Corps, March 1983, p.5-2. 56. Joint Chiefs of Staff, memorandum to the Secretary of Defense, 26 March 1976, "Joint Operational Requirement for a family of VHF/Frequency Modulated Single Channel Tactical Radios", JCSM-110-76. BIBLIOGRAPHY Adrian, Serge, and Rabian, Jacques, "Frequency Hopping for Tactical Radios: the Thomson CSF Philosophy , Special Electronics, January 1984. Electromagnetic Compatability Analysis Center, Draft SINCGARS--V Frequency Management Procedures, study prepared for the U.S. Army signal Center by Troy N. Allen and Lawrence L. O'Neill, October 1984. Electromagnetic Compatability Analysis Center, EMC support for U.S. Marine Corps Communications Planning Concept, study prepared for USMC Development and Education Command by E.R. Velie, September 1984. ITT Aerospace/Optical Division, commercial circular, "SINCGARS-V, The Voice of C3I". Joint Chiefs of Staff, memorandum to the Secretary of Defense, 26 March 1976, "Joint Operational Requirement for a family of VRF/Frequency Modulated Single Channel Tactical Radios," JCSM-110-76. Pipho, S.L., point paper prepared for the USMC Development Center, September 1984, "A Development Strategy for a LFICS/C4I Architecture". Sundaram, G.S., "Anti-Jam Communications: The Spread Spectrum Solution", International Defense Review, March 1978 Sundaram, G.S., "New Concepts in Battlefield Communications Part 2 - slow/medium frequency hopping", International Defense Review, May 1982. United States Marine Corps, Command and Control Master Plan, Headquarters United States Marine Corps, March 1983. Van, P.E., "New Concepts in Battlefield Communications Part 1 - fast frequency hopping", International Defense Review, March 1982.
