Efficient analog-to-residue conversion schemes

The real-time requirements of residue number system (RNS) processing are considered. In conventional real-time systems, one input conversion is performed from analog to binary using commercially available analog/digital converters. In RNS systems, however, a second conversion is required from binary to residue. The elimination of this problem is proposed through the design of high-speed direct analog-to-residue converters. These converters use the principle of binary conversion, but can achieve more throughput because of their simplicity. This technique, based on flash conversion principles, requires a converter for each modulus channel consisting of a simple programmable logic array function at the final stage. For architectures requiring a binary host machine interface, simple input conversion techniques are developed using ROMs and adders. The input binary word is partitioned to suit the ROM input size, resulting in uniform conversion delays throughout the data flow path.