Truth-table look-up parallel data processing using an optical content-addressable memory

Abstract

The extension of truth-table look-up processing beyond primitive operations (such as addition) to higherlevel operations (such as discrete matched filtering) is presented. Use of the residue system and logical minimization techniques to reduce the required number of reference patterns stored in a content-addressable memory is illustrated for 16-bit full-precision addition. Multilevel coding of the numbers is introduced as a method to achieve further truth-table reduction. The required number of reference patterns for implementing the residue addition and multiplication operations are provided for all moduli from 2 through 32 with 2-, 3-, and 5-level coding. An optical holographic implementation of a system that processes multilevel coded numbers is presented.