Further development of a future ESM channeliser with high temperature superconducting filters

An important function of an Electronic Warfare Support Measures (ESM) recei ver is the acquisition and identification of signals in the Electronic Warf are (EW) environment. Ideally the receiver requires a high probability of i ntercept. Current receiver types include wide open systems, which suffer fr om signal overlap, and scanning superheterodyne receivers, which have a low probability of intercept against some signals. The ideal solution is to ch annelise the search bandwidth with each channel monitored continuously. To obtain high frequency resolution many narrow bandwidth filters are required . If miniature conventional filter technology is utilised the insertion los ses become unacceptably high. By using high temperature superconductors (HT S), a channeliser of small size and low loss may be realised, This paper de scribes the recent design and build of an ESM channeliser with potential fo r 2-18GHz operation. It uses eight filter banks, each consisting of twenty superconducting filters with a bandwidth of 100MHz, contained within a cryo genically cooled dewar, Interconnects from the filter banks to the external rf connectors consist of flexible microtrace circuits.