ldpc_optical

3 Commits 1 Branch 0 Tags

Author	SHA1	Message	Date
cah	18333e32f5	Update RTL base matrix to match working Python model IRA staircase structure: col 0 = info (dv=7), cols 1-7 = parity (dv=1-2). RTL decoder core still needs CN update rework for variable degree. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>	2026-02-23 21:56:48 -07:00
cah	b7b76da46e	Fix encoder and decoder - working LDPC simulation - Fixed cyclic shift convention (QC-LDPC P_s is left shift, not right) - Fixed encoder to solve rows sequentially (row 0 first for p1, then 1-6) - Fixed decoder to only gather connected columns per CN (staircase has dc=2-3) - Fixed LLR sign convention: positive = bit 0 more likely - Decoder validates at lam_s >= 4 photons/slot (~90% frame success) Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>	2026-02-23 21:56:15 -07:00
cah	b93a6f5769	Initial LDPC optical decoder project scaffold Rate-1/8 QC-LDPC decoder for photon-starved optical communication. Target: Efabless chipIgnite (SkyWater 130nm, Caravel harness). - RTL: decoder top, core (layered min-sum), Wishbone interface - Python behavioral model with Poisson channel simulation - 7x8 base matrix, Z=32, n=256, k=32 Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>	2026-02-23 21:47:40 -07:00

Author

SHA1

Message

Date

cah

18333e32f5

Update RTL base matrix to match working Python model

IRA staircase structure: col 0 = info (dv=7), cols 1-7 = parity (dv=1-2).
RTL decoder core still needs CN update rework for variable degree.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

2026-02-23 21:56:48 -07:00

cah

b7b76da46e

Fix encoder and decoder - working LDPC simulation

- Fixed cyclic shift convention (QC-LDPC P_s is left shift, not right)
- Fixed encoder to solve rows sequentially (row 0 first for p1, then 1-6)
- Fixed decoder to only gather connected columns per CN (staircase has dc=2-3)
- Fixed LLR sign convention: positive = bit 0 more likely
- Decoder validates at lam_s >= 4 photons/slot (~90% frame success)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

2026-02-23 21:56:15 -07:00

cah

b93a6f5769

Initial LDPC optical decoder project scaffold

Rate-1/8 QC-LDPC decoder for photon-starved optical communication.
Target: Efabless chipIgnite (SkyWater 130nm, Caravel harness).

- RTL: decoder top, core (layered min-sum), Wishbone interface
- Python behavioral model with Poisson channel simulation
- 7x8 base matrix, Z=32, n=256, k=32

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

2026-02-23 21:47:40 -07:00