Patent attributes
The present invention relates to the conversion of signals from RF to baseband using transition functions, or edge functions. These functions typically transition from positive to negative, or from negative to positive, synchronously with the transition of the received pulse signal, effecting detection essentially by synchronously rectifying a signal cycle of the received pulse, producing a net signal at baseband that can be further processed to detect modulation according to the modulation format. It is further disclosed how to configure these systems for optimal reception with a filter optimized for a given detect signal function. Generalizations of the matched filter embodiment lead to further embodiments employing alternative detection functions. Also disclosed is a two-stage version which applies a decode signal to the rectified signal. This step can be performed by a single correlator or by a plurality of correlators in parallel. Coding methods are disclosed to employ two-stage systems for enhanced channelization, and interference rejection.