Bosch INTEGRUS Installation And Operating Manual

Also see for INTEGRUS: Operation manual Installation and operating manual Installation and user instructions Installation and operating manual User manual

Contents

INTEGRUS | Digital Infra-red Language Distribution System en | 7BOSCH Security Systems | February 20031.2 System technology1.2.1 IR radiationThe Integrus system is based on transmission by modulated infra-red radiation. Infra-red radiation forms part of the electro-magnetic spectrum, which is composed of visible light, radio waves and other types of radiation. It has a wavelength just abovethat of visible light. Like visible light, it is reflected from hard surfaces, yet passes through translucent materials such as glass.The infra-red radiation spectrum in relation to other relevant spectra is shown in Figure 1.2.1007514250250400 500 600 700 8005 3900 1000 nm%Figure 1.2 Infra-red radiation spectrum in relation to other spectra1 Daylight spectrum2 Sensitivity of the human eye3 IR radiator4 Sensitivity of IR sensor5 Sensitivity of IR sensor withdaylight filter1.2.2 Signal ProcessingThe Integrus system uses high frequency carrier signals (typically 2-8 MHz) to prevent interference problems with modern lightsources (see section 1.3.2). The digital audio processing guarantees an constant high audio quality.The signal processing in the transmitter consists of the following main steps (see Figure 1.3):1. A/D conversion -Each analogue audio channel is converted to a digital signal.2. Compression - The digital signals are compressed to increase the amount of information that can be distributed on eachcarrier. The compression factor is also related to the required audio quality.3. Protocol Creation - Groups of up to four digital signals are combined into a digital information stream. Extra faultalgorithm information is added. This information is used by the receivers for fault detection and correction.4. Modulation - A high frequency carrier signal is phase-modulated with the digital information stream.5. Radiation – Up to 8 modulated carrier signals are combined and sent to the IR radiators, which convert the carrier signalsto modulated infra-red light.In the IR receivers a reverse processing is used to convert the modulated infra-red light to separate analogue audio channels.A/D Conversion& CompressionA/D Conversion& CompressionAudioChannelAudioChannelProtocol Creation& Modulation4x Carrier (to IR Radiators)4xFigure 1.3 Overview of the signal processing (for one carrier)