A Hybrid Cross-Correlation Data Processing System
A telemetry data processing system based on cross-correlation techniques and maximum-likelihood detection principles and designed to decode a special type of pulse-code modulated (PCM) signals, pulse-frequency modulation (PFM), is discussed. The decoding system employs a high-speed multiple-pass tape scanner to sequentially generate a set of correlation indices for each data word using the alphabet of possible data words. An online digital computer functions as the decision device to select the greatest of the indices as representing the transmitted data word. The data processing system combines analog-digital hybrid techniques for relatively high-speed signal processing and yet requires only a small digital computer memory. Copyright © 1968 by The Institute of Electrical and Electronics Engineers, Inc.
