Reference specifications
Air-interface specs and reference documents that the on-air FEC / channel-coding implementations in this repo derive from. Files land here so a future contributor can cross-check the code against the original source without re-hunting the PDFs from upstream archives. None of these documents are redistributed under a licence that conflicts with the rest of the repo’s MIT licence — they are either openly published (ETSI) or widely-mirrored open references (NXDN Forum, M/A-COM LBI).
| File | What it covers | Used by |
|---|---|---|
nxdn-ts-1-a-v1.3.pdf |
NXDN Forum Technical Specification Part 1-A, Common Air Interface, rev 1.3 — §4.5 channel coding (CAC outbound + Long CAC + Short CAC inbound + SACCH); §4.6 frame structure (RCCH outbound = FSW 20 + LICH 16 + CAC 300 + E 24 + Post 24); §6 RCCH message types. | internal/radio/nxdn/cac_channel.go (155-bit info ‖ CRC-16 ‖ tail → K=5 → puncture(50/350) → 25×12 interleave → 300 bits); internal/radio/nxdn/sacch.go (K=5 + 60-position interleaver + 12-bit puncture + CRC-6); internal/radio/nxdn/process.go (ViterbiSpec mode wires the §4.5.1.1 chain end-to-end). |
etsi-en-300-392-2-v3.8.1.pdf |
ETSI EN 300 392-2 v3.8.1 — TETRA V+D Air Interface — §8.2 RCPC + Reed-Muller + scrambler + (K,a) interleaver primitives; §8.3.1 per-channel coding (BSCH / SCH/HD / SCH/HU / SCH/F / AACH); §9 burst layout. | internal/radio/framing/{rcpc_tetra,rcpc_tetra_sig,rm_30_14_tetra,scramble_tetra,interleave_tetra}.go; internal/radio/tetra/channel_coding.go (per-channel encode/decode helpers); internal/radio/tetra/process.go (SetChannelCoding(ChannelCodingOn) wires the §8.3.1 chain). |
lbi-38463c-edacs-system-manager.pdf |
M/A-COM LBI-38463C — EDACS System Manager Supervisor’s Guide, v3.0 (Group 11) — workstation UI for site reconfiguration, agency partitions, user accounts, dynamic regroup, alarm controls. Kept here as a negative reference: it does not document the air interface, CCW bit layout, BCH parameters, or any channel coding. Future contributors looking for an EDACS air-interface spec should skip this and look for LBI-39031 / LBI-39154 / LBI-38894 instead. | None directly — see internal/radio/edacs/edacs.go package doc for the canonical open reference (lwvmobile/edacs-fm’s bch3.h) the BCH(40, 28, 2) implementation in internal/radio/framing/bch_edacs.go mirrors. |
Provenance + licensing
- NXDN-TS-1-A is published openly by the NXDN Forum (a JVCKENWOOD
- Icom industry consortium). Document marked “Copyright © 2007–2012 JVC KENWOOD Corporation and Icom Incorporated”. Distribution for reference / interoperability is the document’s stated purpose.
- ETSI EN 300 392-2 is published openly by the European
Telecommunications Standards Institute under their standard
IPR policy. ETSI standards are free to download from
etsi.organd are explicitly licensed for reference + research use. - LBI-38463C is a GE / Ericsson Mobile Communications field
service manual from 1990. The “LBI” series was distributed
with EDACS infrastructure as user-operator documentation;
modern survivals appear on radio-archaeology sites
(
repeater-builder.com, archive.org). This copy is preserved for historical reference; the document is ~35 years out of any commercial distribution.
Air-interface specs not in this directory
These would be valuable additions if anyone tracks them down, but were not located at the time of this commit:
- LBI-39031 / LBI-39154 — EDACS Communications Protocol Specification. The closest GE/Ericsson document to a formal air-interface spec. Not publicly distributed.
- LBI-38894 — EDACS Trunked Radio System Description / Theory of Operation. Frame layout + CCW timing.
- LBI-38540 — EDACS RF Subsystem Description (GMSK modulation parameters).
- TIA-102.AABF / TIA-102.BAAA — Project 25 Phase 2
- Phase 1 air interface. Currently the
internal/radio/p25/implementations cite TIA-102 sections in code comments but no PDF is in-tree.
- Phase 1 air interface. Currently the
- ETSI TS 102 361-2 — DMR Tier III air interface.
Pulls welcome.