Index to Constant Weight Codeword Converter
Abstract
A constant weight codeword is a binary n-tuple with exactly r 1's. We show two circuits that generate constant weight codewords. The first is based on the combinatorial number system. Its input is an index to the codeword. That is, there are (n r) n-bit codewords with exactly r 1's. The index generates a unique codeword, and is a binary number between 0 and (n r) - 1. Such a circuit is useful for encoding data. If a random constant weight codeword is needed, as in Monte Carlo simulations, then the index is random. If a random constant weight codeword only is needed, then our other circuit is even more compact. It is based on a trellis configuration. Both designs can be pipelined to produce one constant weight codeword per clock period. We give experimental results showing the efficiency of our designs on the SRC-6 reconfigurable computer.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 2011
- Accession Number
- ADA547615
Entities
People
- Jon T. Butler
- Tsutomu Sasao
Organizations
- Naval Postgraduate School