SECAR¿a modern secondary surveillance radar ground interrogator and decoding equipment

It is shown that there was a need to develop an equipment with special characteristics to meet the requirements of the current admixture of sidelobe suppression standards. Various configurations of interrogator are discussed and that adopted in the SECAR design is described in detail. The concept of `system beamwidth¿ is introduced and discussed in relation to aerial design. Some of the design problems of the decoder are discussed and the application of the chosen technique is described