Parallel Filters Using Error Correction Codes in Modern Signal Processing Circuits

Abstract

As the complexity of communications and signal processing systems increases, so does the number of blocks or elements that they have. In many cases, some of those elements operate in parallel, performing the same processing on different signals. A typical example of those elements are digital filters. The increase in complexity also poses reliability challenges and creates the need for fault-tolerant implementations. A scheme based on error correction coding has been recently proposed to protect parallel filters. In that scheme, each filter is treated as a bit, and redundant filters that act as parity check bits are introduced to detect and correct errors. In this brief, the idea of applying coding techniques to protect parallel filters is  addressed in a more general way. In  particular, it is shown that the fact that filter inputs and outputs are not bits but numbers enables a more efficient protection. This reduces the protection overhead and makes the number of redundant filters independent of the number of parallel filters. The proposed scheme is first described and then illustrated with two case studies. Finally, both the effectiveness in protecting against errors and the cost are evaluated for a field-programmable gate array implementation.