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Guardrail/Common Sensor (GRCS)

System 1 / Hybrid System

The system nomenclatured as the AN/USD-9(C) Special Purpose Signal Detection System is commonly called the Guardrail Common Sensor (GR/CS or GRCS) System 1. The major system enhancement is the Integrated Processing Facility (IPF) distributed processing. The System 1 IPF uses a Fiber Distributed Data Interface (FDDI) open architecture, local area network (LAN) based on a fiber optic, dual, counter-rotating token ring. Universal Workstations that are identical for all operator stations have been incorporated. It has an integrated approach to SIGINT ground processing. Ada is used for all new software. The System 1 IPF is an important step toward a reconfigurable, flexible approach to SIGINT.

Guardrail Common Sensor System 1 was a product improvement to the initial 2 fielded GRCS systems and had all the functionality of the initial GRCS systems in addition to its unique new features. System 1, also known as the Hybrid System, was the first phase toward the System 2, the Objective System, which was to have distributed processing both in the IPF and the airborne payload. System 1 provided the foundation for this objective with new distributed architecture in the IPF and Auxiliary Ground Equipment (AGE). The System 1 IPF was designed so as to be easily retrofitable to the System 2 configuration.

Major enhancements to System 1 include the following:

  • SUN based Universal SIGINT Workstations in the IPF using the FDDI fiber optic local area network (LAN) with file servers and programmable adapter modules (PAM's) to interface the IGDL and special processors to the LAN. Interconnections between units and between vans are via FDDI fiber optics to the maximum extent practical. This improvement allows for future growth, greatly reduces system wiring and enhances TEMPEST and EMI performance
  • The IPF is designed for flexible sizing of the ground processing so that a system could be deployed with 2, 3 or 4 IPF vans. The design interfaces power to each van separately to facilitate van independence
  • Implements Audio Management System (AMS) with improved manipulation capabilities and a digital audio bus using a real time FDDI LAN as the audio bus and employs the workstations/Audio PAM as the audio processors. Audio storage uses an optical disk for record storage and recall of collected signals to any operator position
  • All of the new SIGINT related software upgrades are in Ada and reside in the workstations and PAM's to the extent practical
  • Expands frequency coverage with the integration of Lowband DF/Intercept/search
  • Integrates a new comms Data Distribution System interface (DDS)
  • Modified RC-12N aircraft has increased gross max weight capacity
  • Implements readily available, lighter weight receivers in the ARF
  • Flight line AGE uses PAM's and a new computer
  • AGE upgraded with air-conditioning and with diesel power
  • Performs an accreditation study and implements physical security provisions
  • The IPF is to be growable and readily adaptable to the new System 2 requirements
  • Re-uses software from GRCS as economics dictate and applies workstation based MMI software/architecture
  • Integrates CTT (SI-Hi) in the IPF/ARF/AGE and integrates the interference canceller in the ARF
  • Provides an upgraded power distribution system
  • Provides Multi level reproting with man-in-the-loop oversight

The RC-12N is the GRCS System 1 aircraft. Aircraft enhancements provide antenna provisions for low band antenna provisions and a 16,200 pound gross maximum capacity.

Some of the enhancements were developed on other programs. For example, DDS is similar to the ASAS communications control set. Other NDI System 1 enhancements include Lowband integration, airborne FDDM and Smart File Cabinet/FasTrack. Lowband is an EDM intercept/DF subsystem that is being deployed on System 1 and fills the Guardrail operational need for low band search, collection and DF, and provides a sky wave/co-channel capability to make airborne collection practical in a real world environment.

Guardrail Common Sensor System 1 has an ARF payload rack configuration that is similar to GR/CS systems 3 and 4 in that it employs similar COMINT equipment, the IADL, AQL and CHAALS. The LRIP CTT relay is new and it has new WJ-8604 intercept receivers, and has Lowband DF/intercept provisions.

The System 1's operational configuration differs from System 4 in that it can operate with as few as two IPF vans at a time Vs all four. This allows greater deployment mobility and flexible system sizing. The internal configuration of the System 1 is vastly different than other GRCS systems. Standard "re configurable" workstations make this practical and the workstations allow software to replace most of the formerly unique IPF hardware. System 1 employs a lot of NDI and ruggedized COTS equipment such as the workstations, MSC, LAN, servers and PAM's. Where economics dictate, System 1 re-uses GRCS software extensively.

System 1 has multiple functions that are distributed among its several major subsystems and its functional segments.

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Page last modified: 24-04-2012 18:40:12 ZULU