Failure resistant digital filters based on residue number system product codes

Residue number system product codes are proposed for the design of self-checking digital filters. It is shown that product codes require redundancy that is similar to, but slightly less than that of systematic codes for simultaneous overflow detection and single error correction. The design of a product code error checker is presented, and compared to a systematic code error checker. Also, a new concept called expanded mixed radix conversion is presented to simplify the error checker hardware design.