BS 7693:1993

Committees responsible
National foreword
Guide
1. Scope
2. Infra-red transmission
2.1 The use of infra-red radiation as a transmission
       medium
2.2 Advantage of IR transmission
2.3 Limitations of IR transmission
3. Transmission systems and disturbing sources
3.1 Transmission systems
4. Applications
4.1 Remote control
4.1.1 Applications
4.1.2 Systems and characteristics
4.1.3 Performance
4.2 Audio transmission
4.2.1 Applications
4.2.2 Broadband systems (BBS)
4.2.3 Multi-channel narrowband systems
4.2.4 Technical data (typical values)
4.3 Data transmission
4.3.1 Application
4.3.2 Existing or experimental systems
4.3.3 Performance
5. Disturbances
5.1 Causes by daylight (sunlight)
5.2 Caused by radiation from artificial light sources
5.2.1 General
5.2.2 Incandescent lamps
5.2.3 Tubular fluorescent lamps
5.2.4 High pressure gas-discharge lamps
5.3 IR-disturbances caused by the simultaneous use
       of more than one infra-red application (including
       interference table)
6. Prevention and reduction of interference
6.1 General
6.2 Light sources
6.3 Transmission systems
6.3.1 Remote control
6.3.2 Audio transmission (frequency multiplex/time
       multiplex)
6.3.3 Data transmission
6.4 Optical filtering
7. Conclusion
Figures
1. Frequency spectrum of a biphase modulation system
2. Frequency spectrum of a pulse distance modulated
     system
3. Spectral responses of three types of IR diode
4. Response characteristics of typical IR remote
     control receivers
5. Maximum permitted disturbing irradiance against
     wavelength
6. Measurement circuit
7. Emission spectrum S(lambda) of an IR emitter,
     transmission spectra (Tn(lambda)) of two different
     dyes and spectral response D(lambda) of the
     different signal of two counteracting diodes

Recommendations for preventing disturbances from primary or unintended infra-red sources so as to leave intended transmission undisturbed. Excludes safety requirements, optical fibre communications, alarm systems, infra-red telemetry and traffic information systems.

This report gives recommendations for preventing disturbances from primary or unintended infra-red sources so as to leave intended transmission undisturbed.

Typical specifications of existing IR transmission systems and a summary of disturbing sources are listed in clause 3.

Excluded from this report are:

• safety requirements;
• optical fibre communications;
• alarm systems;
• infra-red telemetry;
• traffic information systems.