Overview
IEC 60728-9:2000 defines physical interfaces for interconnecting professional cable distribution equipment that exchange digitally modulated signals - in particular the transfer of MPEG‑2 transport streams (TS) between headend and signal‑processing devices. The standard targets professional CATV / SMATV headend equipment and similar systems (for example up‑link stations), specifying how MPEG‑2 packets are carried between devices over parallel, serial, coaxial and optical media.
Key topics and requirements
- Scope: Interfaces for the interconnection of signal‑processing devices carrying MPEG‑2 transport packets; RF interfaces and direct telecom network interfaces are excluded.
- Transport stream formats: Support for MPEG‑2 TS packetization (188‑byte packets and 204‑byte packets when Reed‑Solomon FEC is used). Terms such as PSYNC (packet sync) and DVALID (data valid) are defined.
- Specified interfaces (see clauses and annexes):
- SPI - Synchronous Parallel Interface (signal format, clock, electrical and connector details)
- SSI - Synchronous Serial Interface (normative Annex A)
- ASI - Asynchronous Serial Interface, with coaxial (ASI‑C) and optical (ASI‑O) variants (normative Annex B)
- 3WI - 3‑Wire Interface (informative Annex F)
- Coding and signalling: 8B/10B coding tables (informative Annex C) and running‑disparity/clock‑recovery considerations.
- Implementation guidance: Clock recovery, deriving clocks from MPEG‑2 packets and practical implementation notes provided in Annexes D and E.
- Mechanical and connector references: Normative references include common connector and fibre specifications (e.g., BNC, SC), and electrical interface recommendations.
Applications and users
IEC 60728-9 is used by:
- Headend equipment manufacturers (multiplexers, demultiplexers, QPSK demodulators, QAM modulators).
- System integrators and CATV/SMATV operators deploying professional distribution networks.
- Satellite uplink and contribution facilities that pass MPEG‑2 TS between processing stages.
- Test engineers specifying interface conformance, clock recovery and bit‑level interoperability.
Practical benefits include reliable device interoperability, consistent handling of MPEG‑2 TS packet lengths and clocking, and clear guidance for deploying ASI/SSI/SPI over coaxial and optical media.
Related standards
- ISO/IEC 13818‑1 (MPEG‑2 Systems) - transport stream definition
- ETS 300429 / ETS 300421 - related digital broadcasting framing and modulation guidance
- Other parts of IEC 60728 series (notably IEC 60728‑5 for RF/video/audio headend interfaces)
Keywords: IEC 60728-9, MPEG-2 transport stream, ASI, SSI, SPI, CATV headend, SMATV, MPEG-2 TS, optical fibre, coaxial, 8B/10B, clock recovery.
Open preview (PDF)Cabled distribution systems for television and sound signals - Part 9: Interfaces of cabled distribution systems for digitally modulated signals
