secondary surveillance radar


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Related to secondary surveillance radar: primary radar, ATCRBS

secondary surveillance radar

[′sek·ən‚der·ē sər′vā·ləns ‚rā‚där]
(navigation)
The secondary radar that operates in conjunction with the airborne transponder of the air-traffic control radar beacon system (ATCRBS).

secondary surveillance radar (SSR)

A radar system that requires complementary aircraft equipment (transponder). The transponder generates a coded reply signal in response to transmissions from the ground station (interrogator). Since this system relies on transponder-generated signals rather than signals reflected from the aircraft, as in primary radar, it offers significant operational advantages, such as increased range and positive identification. The interrogator has a fixed interval of two microseconds between pulses P1 and P2, but the position of P3 is variable. There are four modes, or types, of reply allocated for civil; they are designated A, B, C, and D. All secondary surveillance radars operate on the same frequencies; the interrogation is at 1030 MHz and the transponder reply is at 1090 MHz. It also provides automatic altitude reporting facilities as well as other types of information to the ATC (air traffic control) controller. The three main components of the system are the interrogator, a transponder (fitted in the aircraft), and a radarscope. Also called an air traffic control radar beacon system (ATCRBS).
References in periodicals archive ?
It provides an outline of modern primary radar sensor systems and covers the theory and evolution of secondary surveillance radar and the development of monopulse processing.
For its part, SIR-S is a Mode S capable monopulse secondary surveillance radar that conforms with Eurocontrol POEMS requirements, is fully solid-state and is fitted with an ALE 9 open array antenna.
The mobile radar system, three radars in one, includes a mobile airport surveillance radar providing bearing and range information to controllers, a secondary surveillance radar which overlays flight code and altitude data on the controller's screen, and a precision approach radar.
As well as a planned new single-centre Air Traffic Control Centre at Ankara, DHMI is also looking at renewing its radar coverage of the country through the purchase of six secondary surveillance radar and three primary surveillance radar.
The Roke Manor solution utilises the measurement of difference in time of arrival (DTOA) of aircraft secondary surveillance radar (SSR) Mode A and C replies at a multiple receiver site.
Under the contract, Airsys ATM will deliver a STAR 2000 state-of-the-art solid state S-band primary radar, a RSM 970S monopulse secondary surveillance radar and a Eurocat 2000 air traffic control system.