A rapid channel detection system for EW receivers

Strategies for the rapid, accurate identification of the input signal frequency generally fall into one of two classes. The first uses broadband techniques to simultaneously cover all frequencies, maintaining a high probability of intercept at the expense of possible overload in dense multiple-signal environments. The second class uses narrowband receivers that are swept or clustered in channels in some way to cover a broad range. This compromises probability of intercept for the ability to filter out certain signals in dense environments. A unique RF/digital subsystem that attempts to combine the merits of these two strategies is described. It uses a low-resolution, ultrafast IFM (instantaneous frequency measurement) to provide real-time signal frequency information that can be used to dynamically allocate receiver resources. Incorporating this type of subsystem in the RF or IF section of a receiver opens up new possibilities for system architecture by providing useful signal processing capabilities much earlier in the RF chain than previously possible.<>