Also known as: BPTC, BPTC(196,96), block product turbo code

BPTC (block product turbo code), specifically BPTC(196,96), is the forward-error-correction scheme that protects DMR data and control bursts.¹ It arranges bits in a grid and applies parity across both rows and columns, so the two passes can correct errors the other misses.

BPTC computes parity across both rows and columns of a bit grid, with interleaving to spread bursts.

Overview

The “product” structure plus interleaving makes BPTC robust against the burst errors typical of a fading mobile channel — important for the CSBK control messages that keep a trunked DMR system coordinated.

Sources

1. Digital mobile radio — Wikipedia, for the DMR standard whose data and control bursts BPTC(196,96) protects. ↩

See also

• Forward error correction (FEC)
• Hamming code
• Interleaving
• Digital Mobile Radio (DMR)
• CSBK

Learn it step by step

• The demodulation pipeline

From the blog

• SDR Internals, Part 9: Framing & forward error correction