12.3 A Scalable and Instantaneously Wideband 5GS/s RF Correlator Based on Charge Thresholding Achieving 8-bit ENOB and 152 TOPS/W Compute Efficiency

Correlators are fundamental building blocks in radar/communication signal processing and analog-to-information (A-to-I) applications such as spectrum sensing [1]. Typically, correlation, which is equivalent to an inner (dot) product, is performed using digital multiply-and-accumulate (MAC) operations (Fig. 12.3.1), with power consumption scaling with frequency, compute, and ADC power. Analog correlators eliminate ADCs but suffer from high power/area and/or small correlation lengths (~10 samples) [2], [3]. While matrix multiplication in compute-in-memory (CiM) cores can be used for correlation, such blocks typically operate with lower speeds for multi-bit inputs, require new materials/memory IP and DACs and ADCs at the input/output [4], [5].