Alternative LDA/PDA signal processing algorithms and their implication for hardware design

The paper discusses techniques for the digital processing of LDA signals and introduces new methods which offer the potential for large gains in processing speed coupled with significant economies in hardware costs. Following an asessment of the Zero Crossing technique, the paper examines the feasibility of two alternative methods in which the Doppler signal is reduced to a sequence of single bit numbers. In a simulation study, the susceptibility of the different systems to noise has been assessed using both computer generated and real LDA signals. It is found that each single bit method operates successfully at SNR values in excess of 5, and that one method performs well down to SNR values of 3. Finally, a hardware scheme is discussed which enables the single bit processing techniques to be realized.