IEC 61603-6:2001

Overview

IEC 61603-6:2001 - "Transmission of audio and/or video and related signals using infra‑red radiation - Part 6: Video and audio‑visual signals" specifies requirements and measurement methods for analogue infrared (IR) single‑channel video transmission systems not covered by IEC 61603‑1. It defines how to describe transmitter and receiver performance (radiant intensity, irradiance, directivity), transmission formats (composite and Y/C), modulation schemes and key interface values to allow compatibility and interference assessment.

Key topics and technical requirements

• Scope: Analogue single‑channel IR video links for consumer/indoor applications (VCR, camera, video disc player).
• Wavelength: Peak 800 nm to 1 000 nm.
• Bandwidth: 24 MHz overall; component bandwidths and limits for PAL/NTSC are specified (e.g., NTSC 100 kHz–4.2 MHz, PAL 100 kHz–5.0 MHz).
• Modulation: Dual‑stage - infrared intensity modulation by a sub‑carrier, with the sub‑carrier frequency‑modulated by video (composite or Y/C). Y (luminance) and C (chrominance) sub‑carriers are treated separately for Y/C signals.
• Performance metrics:
  • Transmitter radiant intensity (I, mW/sr) and receiver irradiance (E, mW/m2).
  • Receiver minimum irradiance specified for an unweighted S/N = 40 dB under defined signal and bandwidth conditions.
  • Video level relative to audio: video must be at least 10 dB higher (recommended 15–25 dB).
• Transmitting distance & directivity:
  • Formula relating radiant intensity and receiver irradiance to calculate distance: d = sqrt(I0 / E).
  • Directivity measured by radiant intensity/irradiance vs. vertical/horizontal angles.
• Measurement & environmental conditions:
  • Test conditions: 15–35 °C, 45–75 % RH, illumination 500–1 000 lx on receiver surface; minimize room reflections or apply corrections/ND filters.
  • Spurious emission measurement band 0–100 MHz with specified test arrangements.
• Signal formats: Composite video and Y/C (separated) formats and their transmission formats are described.

Applications and who uses this standard

• AV equipment manufacturers designing IR transmitters, radiators and receivers for set‑top boxes, wireless video links, and consumer AV accessories.
• Test laboratories and QA engineers performing conformity, performance and interference tests on IR video systems.
• System integrators and installers specifying component compatibility and expected range/directivity in indoor environments.
• Standards bodies and product managers ensuring interoperability with IEC 61603‑1 and IEC 61603‑2 guidelines.

Related standards

• IEC 61603‑1: General requirements and measurement methods for IR transmission systems
• IEC 61603‑2: Audio transmission systems using infrared
• IEC 61938: Preferred matching values of analogue audio/video signals

Keywords: IEC 61603-6, infrared video transmission, IR video, infra‑red radiation, composite video, Y/C video, radiant intensity, irradiance, bandwidth 24 MHz, 800–1000 nm.