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P-20 / Pereskop / TOKEN

1952P-20 PereskopTOKEN
1956P-30 KhrustalBIG MESH
1958P-35/37BAR LOCK
1959P-30MBIG BAR A
1960P-30MBIG BAR B
1960P-30MBIG BAR C
The TOKEN radar was an early warning radar with twin truncated wire mesh antennae similar to a widely deployed radar code-named BAR LOCK. In the early warning mode of operation the TOKEN radar had a range of 250-300 km with a 1 km accuracy. It operated in the 2.7-3.1 GHz range, had a pulse repetition frequency (PRF) of 375 pulses-per-second (pps). The pulse duration was 1.6-3.1 microseconds. So, interestingly both radars operated near 3 GHz. The TOKEN radar operated in the “S-band” frequency around 3,000 megacycles.

First detected in Moscow in 1951, the new GCI radar could direct several fighters simultaneously at ranges up to 70 miles away. This Soviet V-beam equipment was inspired by the U.S. AN/CPS-6 V-beam set, not released under the Lend Lease Policy but documented in the MIT Series reports.

Soviet radar P-20 Peryskop work began in 1946, at the Research Institute No. 20, later connected with the Institute of Radio Engineering - NNIIRT in Nizhny Novgorod. Soon, on the basis of the P-20 was created more advanced radar P-30. In terms of reliability and tactical and technical data, it surpassed all domestic locators of the time. After the P-30 came to light P-35, then P-37, in which the semiconductors replaced the tubes, microchips. In these two-coordinate radars, radio-altimeters were additionally included in the composition of the complexes, which made it possible to accurately determine the height of the target. The last station P-37 absorbed all the achievements of that period.

The Institute was tasked with developing a stationary and mobile warning radar for ground control and interception for Soviet aviation. The P-20 was the first radar of the Moscow empire with a decimeter wavelength and the first three-coordinate radar (3D). The prototype was built in 1947, and in 1949. was introduced to the armaments. The P-20 in the mobile version consists of a set of 8 ZIL-151 trucks and trailers. Antenna system consisting of two parabolic antennas. One of the antennas is inclined at an angle of 45 degrees. this causes each target on the pointer to appear twice. The distance between these two echoes allows the operator to estimate the height (ceiling) of the moving object. The radar has 4 indicators to display, plus one widescreen. The radar has 5 separate channels; three for the upper antenna, two for the lower antenna. Each channel uses a different frequency. The P-20 radar became the progenitor of a series of radars, including P-30, P-35 and P-37.

The mobile radar P-20 was the first station for early detection and guidance in the centimeter wavelength range. Its development was conducted on the instructions of the Air Force in accordance with the 3-year plan for the development of radar for 1946-1948. The station provided all-round visibility and target detection in its area of operation, and displayed the air situation on the station screen and on the remote PIR of the aviation unit.

The radar determined the three coordinates of the targets: azimuth, slant range and altitude using a V-beam, the idea of ??which was expressed by prof. M.A. Bronch-Bruevich as far back as 1938. To identify their aircraft to the station, a query device NRZ-1 was attached. The width of the radiation pattern: a vertical beam in the horizontal plane from 0.5 to 3°, in the vertical - 20 °; inclined beam –– in an inclined plane from 1 to 3 ° and in a vertical plane from 2 to 18°.

The station had five emitting and five receiving channels, each working in its own centimeter-wave band. Three channels worked on an antenna device with a flat (fan) radiation pattern to search for planes in the horizontal plane and determine the azimuth and distance to targets (vertical beam). Two channels operated on an antenna with an inclined radiation pattern (flat, fan), which, in combination with a vertical beam, determined the altitude of the targets.

The composition of the station with the equipment and units of the power plant consisted of eight transport units. In the rotating receiving and transmitting van, five high-frequency cabinets were installed with magnetron generators, receivers and equipment necessary for radiation and reception. Antenna devices were mounted on the roof of the van. The station had four indicators: circular view, remote (VIKO), range indicator and altitude indicator. The station was the most complex radar device. Its operation required the service personnel to use engineering knowledge and experience to infuse numerous radio units and devices.

The development of the radar station conducted a team of radio industry under the leadership of L.V. Leonov with the participation of A.R. Volperta, Yu.K. Adel, S.P. Zavorotischeva and many other engineers of the institute. In 1949, the Air Force held state tests of the station (the chief test engineer, II Vasyutin) and showed compliance with the specified requirements of the Air Force. Being put into service, the P-20 station was widely used in the Air Defense Forces, Air Forces, Navy and at large airfields of the Civil Air Fleet (GVF) as a dispatch station.

It should be noted that a large engineering and organizational activity in the development of this station and a number of other radar early warning and guidance systems in the post-war years K.L. Kurakina (later Deputy Minister of Electronic Industry), who was awarded the USSR State Prize in 1950.

This locator was a real long-life among its fellows. They began to create it at the former car-repair plant, which literally over a year later was converted into an electromechanical giant. In December 1952, the first radar appeared, with 300 sets of P-20. The unsightly gear, mounted on an medium artillery gun carriage, worked very reliably. It was necessary to place the radar high in the mountains. But the equipment was quickly ionized and failed, cathode ray tubes, and circular view indicators were burnt. All this was due to the strong discharge of air. The chief designer of the alpine radar, Lev Shulman, was still able to find the right solutions, and in just half a year the mountain version of the P-20 was created and tested in a boron chamber and in Armenia on Mount Alagez.

There were even more serious alterations in which Lianozovo radars and their creators fell. For example, seven stations "Ether" were placed in the depths of the Kazakh steppes, ranging from the range Kapuskin Yar to Lake Balkhash. They followed the test flights of the first cruise missiles of the chief designer Lavochkin.

By late 1951 TOKEN stood out as the beginning of a generation of Soviet-built radars. This generation consisted of two subgroups, V-beam radars, and multi-search radars. By mid 1952, at least 50 V-beam radars, were spread across the U.S.S.R. and surrounding satellites from East Germany to Vladivostok. This radar was obviously inspired by the U.S. AN/CPS-6 V-beam set. Although not provided for or available under the lend-lease program, it was contained in the MIT series. This set was constructed with IAGC and FIC circuitry: basic ECCM features which produced a limited capability against long pulse jamming and jamming with low modulation frequencies.

The Pereskop had three scopes, one directly above the other. The first or top one was for area scan (ekran krupnogo obzora), the second for sector scan, and the third for height finding. Ordinarily the Pereskop was used on area scan. At the appearance of a target, the radar was switched from area to sector scan. To determine height, the sector scan was switched off and the height finder or bottom scope was turned on. Should the Pereskop operator doubt that a target in his scope is moving, he can cut out the lobes which are focused on the stationary target and apply his other lobes until he locates the target. The operator himself must determine whether or not the target is moving. Operator were highly pleased with the overall operation and performance of the Pereskop. It was very effective so long as the aircraft made no sudden changes in course and/or altitude; such changes made tracking very difficult if not impossible.

If the Communist Ground Control Intercept [GCI] net had depended on the equipment they possessed at the start of the Korean War the threat would not have been severe, but by the fall of 1951 the US Air Force had obtained ominous evidence of a vastly improved Soviet radar, nicknamed "TOKEN". The US Air Attache in Moscow had obtained photographs of a new radar which bore a marked resemblance to the American CPS-6, the most modem GCI radar in use by the US.

With five transmitters operating in the S-Band frequency range (about 3000 MHz), not only could the TOKEN radar control several fighters simultaneously at ranges up to 70 miles away, it also operated in a frequency range against which US Far East Air Force [FEAF] had no jamming capability. Indeed, SAC had only a few jammers throughout the entire command effective against it. In January 1952, a 5th Air Force intelligence summary stated that TOKEN by itself did not improve Soviet night interception capabilities. This would shortly be proven erroneous, as the Russians would soon use TOKEN to vector fighters into attack position against bombers illuminated by radar-controlled searchlights.

For the final 18 months of the Korean War, growing Communist radar defenses threatened USAF strategic air operations in Korea. The total number and sophistication of the Soviet radar net increased significantly. By December 1951, 13 RUS II (or “DUMBO”) radars operated in the Sinuiju to Sariwon, Korea, area alone. During this period, a new type of high-frequency GCI radar, nicknamed “TOKEN,” appeared. An S-band radar of the TOKEN type was identified at Antung, from where it could control fighters out to nearly 100 mile.

By June 1952, Soviet radar sites guided enemy night fighters to intercept FEAF bomber formations. During the latter half of 1952, the communists coordinated AAA gun-laying radar with searchlights to illuminate bombers, aiding both their night fighters and AAA. As a result, FEAF Bomber Command lost six B-29s and four crews during the month of December alone. Fortunately, the Communists lacked adequate air intercept radar in their night fighters that would enable them to close for the final kill.

The USAF Bomber Command still did not have a jammer effective against the TOKEN radars operating in the S-band frequency range. Although Bomber Command never did get a satisfactory counter to the TOKEN GCI radar, that was not the critical link in the enemy defensive system. The link that had to be broken was the searchlight control radar, because the entire defensive effort rested on illuminating the bomber so the MIG could see it to attack.

By 1952 the situation would improve slightly, because the addition of the APT-16 jammer would significantly increase both the jamming power and frequency coverage available against the S-band in which the Soviet TOKEN radar operated. Even here, however, the full capabilities of the new jammer would be lost without an ECM operator for the equipment.

By mid-1952 at least 50 TOKEN radars had been deployed across the USSR from East Germany to Vladivostok, and by 1 July 1953 the figure reached 115. The large increase in the number of TOKEN radars lead the U.S. to believe that Soviet technicians were more successful at maintaining them than had been anticipated on the basis of U.S. experience with the AN/CPS-6.

In the years 1952-1955. the ordinance of the Chief of General Staff of the Polish Armed Forces is formed by mobile squadrons protecting the blind landing. They were organized at airports; Bemowo, Slupsk, Pruszcz Gdanski, Malbork, Mierzecice, Modlin, Swidwin, Krzesiny, Strachowice, Bydgoszcz, Sochaczew, Leczyca, Babimost, Orneta, Zegrze Pomorskie, Debrzno, Goleniów, Nowe Miasto nad Pilica, Lask, Balice and Minsk Mazowiecki. The squadrons receive a closer and distant radio beacon with the radion-sensor and light system, and the RSP-5 blind-landing radar system. In 1957 squadrons of blind landing were included in the air-technical battalions as the company of earth security flights. Also in the period 1952-1955. the existing observation and reporting battalions were reformed into radio technical regiments. In total, five radio technology were formed. In 1954, a Center for Training of Radiolocation Specialists in Przasnysz is being created.

From the beginning of 1955, a total of 32 radiolocation stations worked in Poland, and from the beginning of 1956. there were 65 radiolocation stations on the armaments, although the service provided 202 radar stations. At that time, the Air Forces and Defense of the Anti-aircraft Area of ??the Country had about 73,000 soldiers, of which about 10,000 soldiers served in the Radio-technical Forces.

By 1953, initial post war early warning had been strengthened by wide-scale deployment of the TOKEN radar. This directly complemented the growth of jet fighters as the dominant and most significant part of the Soviet air defense forces. Soviet radars provided warning and made the fighter more effective by facilitating intercept. Later in the decade, a large-scale deployment of surface-to-air missiles would make ground systems the backbone of the PVO.

P-20 radar
Stationary and mobile radar
warning ground control and interception of air targets
three-coordinate (3D)
RangeUp to 190 km / 250 km (155 miles)
Power up to 1 MW
Radiation power of each channelAbout 1000 kW
Pulse durationAbout 1 µs
Range elevation of 18 km (60,000 ft)
Azimuth 360 degrees
  • 400 m / 460 m in range and
  • 1.3 ° / 1.5 degrees in azimuth.
  • Coordinate errors:
    azimuth± 0.5 °
    heights± 500 m
    Beam width: vertical beam
  • in the horizontal plane from 0.5 to 30,
  • in the vertical - 200;
  • Beam width: inclined beam
  • in an inclined plane from 1 to 30 and
  • in a vertical plane from 2 to 180.
  • TOKEN Radar TOKEN Radar P-20 Radar P-20 Radar P-20 Radar P-20M Radar

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    Page last modified: 24-07-2019 19:13:52 ZULU