Technical data

16 en | Planning Integrus
IOM-INT | V1.1 | 2010.12 Installation and Operation manual Bosch Security Systems B.V.
4 Planning
4.1 System technology
4.1.1 IR radiation
The Integrus system is based on transmission by modulated infra-red radiation. Infra-red
radiation forms part of the electromagnetic spectrum, which is composed of visible light,
radio waves and other types of radiation. It has a wavelength just above that 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 4.1.
Figure 4.1 Infra-red radiation spectrum in relation to other spectra
4.1.2 Signal Processing
The Integrus system uses high frequency carrier signals (typically 2-8 MHz) to prevent
interference problems with modern light sources (see section 4.2.2 ). The digital audio
processing guarantees a constant high audio quality.
The signal processing in the transmitter consists of the following main steps (see Figure 4.2):
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 each carrier. 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 fault algorithm 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.
1 Daylight spectrum
2 Sensitivity of the human eye
3 IR radiator
4 Sensitivity of IR sensor
5 Sensitivity of IR sensor with daylight filter
100
75
1
4
2
50
25
0
400 500 600 700 800
53
900 1000 nm
%