BCH codes (Bose–Chaudhuri–Hocquenghem) are a class of cyclic block
error-correction codes that can be constructed to
correct a chosen number of bit errors.1
BCH codes append algebraically-computed parity bits that correct multiple bit errors per codeword.
How it works
A BCH codeword adds algebraically structured parity bits; the decoder computes a syndrome
to locate and fix errors. POCSAG uses BCH(31,21), and
DSC uses a small BCH code.
Relevance to SDR
BCH decoding lets GopherTrunk recover paging and signalling messages even when a few bits
are corrupted.
Sources
BCH code — Wikipedia, for the cyclic code family and its designed error-correction capability. ↩
Stuck on a system, IDing a mystery signal, or have a feature in mind? Swap notes with other operators on Discord and Reddit — questions get answered fast.
