5N62B - SQUARE PAIR Radar

For early detection of air targets, the S-200 air defense system is assigned an air reconnaissance radar of the P-35 type and others. The radar of target illumination is a high-potential radar station for continuous radiation. It maintains the target and produces information for launching the missile. In addition, it highlights the targets in the process of homing the missile. The starting battery has six launchers, which are arranged around the ROC. They carry out storage, pre-launch preparation and launch of anti-aircraft missiles.

Each missile battalion has one P-35M (NATO designation BARLOCK-B) E/F-band 320 km range target search and acquisition radar with an integral D-band IFF system, one H-band NATO designation Square Pair 270 km range missile guidance radar, and six trainable semi-fixed single rail launchers.

The S-200 air defense missile system includes the K-9M control and target designation point, the RSC 5N62B radar target radar (K-1V antenna post, K-2V booth), the 5Z51 start battery (K-3V start-up preparation booth, 5P72V launcher, charging machines 5YU24M, anti-aircraft guided missiles 5N21 and 5N28), power supplies - diesel-electric power stations. For early detection of air targets, the ZRDN is assigned to an airborne reconnaissance radar of the P-35 type and others.

The 4.5-cm band radar of the target (RTC) included an antenna post and a hardware booth and could operate in coherent continuous radiation mode, which provided a narrow spectrum of the probe signal, provided high noise immunity and maximum target detection range. At the same time, the simplicity of performance and the reliability of the GOS operation were achieved. However, in this mode, it was not possible to determine the range to the target, which is necessary for determining the moment of launching the missile, and also for constructing the optimal trajectory of aiming the missile at the target. Therefore, the ROC could also realize a phase-code modulation mode that slightly broadens the spectrum of the signal, but provides a range to the target.

The probing signal of the radar of target illumination reflected from the target was taken by the homing head and the semi-active radio fuse associated with the GOS, operating on the same target echo signal as the GOS. A control responder was also included in the complex of the radio-technical airborne equipment of the missile. The target illumination radar operated in the continuous emission mode of the sounding signal in two basic modes of operation: monochromatic radiation (MXI) and phase-modulation (FM).

The target illumination radar (RPN) 5N62B is a high-potential radar station for continuous radiation. It carries out the tracking of the target, develops information for launching the missile, highlights the targets in the process of homing the missile. The construction of the ROC using continuous monochromatic sounding of the target and, accordingly, Doppler filtering of the echoes, ensured the resolution (selection) of targets by velocities, and the introduction of phase-code manipulation of the monochromatic signal - over the range.

Thus, there are two main operating modes of the target radar - MCH (monochromatic radiation) and PCM (phase-shift manipulation). In the case of the application of the MXI regime, the ROC airspace is escorted in three coordinates (elevation angle - it is the approximated altitude of the target, - azimuth, speed), and the FCM - four (the listed coordinates are added range).

When switching to the FCM mode, the operator performs a so-called range ambiguity selection (which requires considerable time-consuming), the signal on the screens acquires the "normal" form of the "collapsed signal" and there is the possibility of accurately determining the range to the target. This operation usually takes up to thirty seconds and when firing at short distances is not applied, because the choice of ambiguity in range and the time the target is in the launch zone is of the same order of magnitude. In the MXI mode on the screens of indicators in the control cabinet of the S-200 SAM system, the marks from the targets look like glowing stripes from the top to the bottom edge of the screen.

When switching to the FCM mode, the operator performs a so-called range ambiguity selection (which requires considerable time-consuming), the signal on the screens acquires the "normal" form of the "collapsed signal" and there is the possibility of accurately determining the range to the target. This operation usually takes up to thirty seconds and when firing at short distances is not applied, because the choice of ambiguity in range and the time the target is in the launch zone is of the same order of magnitude.

The United States raised the testlng of Soviet Square Pair SAM Radars in an ABM Mode. The ABM treaty progvided that to enhance tthe effectiveness of the limitations on ABM systems, and their components, each Party "undertakes not to give missiles, launchers, or radars; other than ABM interceptor missiles, ABM launchers, or ABM radars, capabilities to counter strategic ballistic missiles or their components in flight and not to test them in an ABM mode."

On April 7, 1972, the U.S. Delegation made the following statement: "Article II of the Joint Text Draft uses the term "tested in an ABM mode," in defining ABM components, and Article VI includes certain obligations concerning such testing. We believe that the sides should have a common understanding of this phrase. First, we would note that the testing provisions of the ABM Treaty are intended to apply to testing which occurs after the date of signature of the Treaty, and not to any testing which may have occurred in the past. Next, we would amplify the remarks we have made on this subject during the previous Helsinki phase by setting forth the objectives which govern the U.S. view on the subject, namely, while prohibiting testing of non-ABM components for ABM purposes: not to prevent testing of ABM components, and not to prevent testing of non-ABM components for non-ABM purposes. To clarify our interpretation of "tested in an ABM mode," we note that we would consider a launcher, missile or radar to be "tested in an ABM mode" if, for example, any of the following events occur: (1) a launcher is used to launch an ABM interceptor missile, (2) an interceptor missile is flight tested against a target vehicle which has a flight trajectory with characteristics of a strategic ballistic missile flight trajectory, or is flight tested in conjunction with the test of an ABM interceptor missile or an ABM radar at the same test range, or is flight tested to an altitude inconsistent with interception of targets against which air defenses are deployed, (3) a radar makes measurements on a cooperative target vehicle of the kind referred to in item (2) above during the reentry portion of its trajectory or makes measurements in conjunction with the test of an ABM interceptor missile or an ABM radar at the same test range. Radars used for purposes such as range safety or instrumentation would be exempt from application of these criteria."

Standing Consultative Commission meting in Geneva on November 1, 1978 adopted an Agreed Statement: "The term "tested in an ABM mode" used in Article II of the Treaty refers to: "an ABM radar if it has tracked a strategic ballistic missile or its elements in flight trajectory and guided an ABM interceptor missile toward them regardless of whether the intercept was successful or not; or tracked and guided an ABM interceptor missile; or tracked a strategic ballistic missile or its elements in flight trajectory in conjunction with an ABM radar, which is tracking a strategic ballistic missile or its elements in flight trajectory and guiding an ABM interceptor missile toward them or is tracking and guiding an ABM interceptor missile.

"The term "tested in an ABM mode" shall not be applied to a radar, including a phased-array radar, which is not an ABM radar or a radar referred to in paragraphs 5 and 6 of this Section, if strategic ballistic missiles or their elements passed through the field of view of the radar while it was operating in accordance with its mission, and it was not, at that time, performing functions inherent only to an ABM radar, and it was not functioning in conjunction with an ABM radar. In the event that ambiguities arise in the future regarding application of the term "tested in an ABM mode" to individual radars which track strategic ballistic missiles or their elements in flight trajectory, the Parties, in accordance with Article XIII of the ABM Treaty, will consider such questions in the Standing Consultative Commission and resolve them on a mutually acceptable basis."

The Soviets did not accept the US-proposed ban on using AD radars making measurements on SBMs during reentry.