Bosch Appliances 3122 475 22015en manual Overlapping footprints and multipath effects

INTEGRUS Installation and User Instructions System description and planning en 6

Figure 1.14 Combination of several reflected signals

For concentrically arranged conference rooms, central- ly placed, angled radiators located high up can cover the area very efficiently. In rooms with few or no reflecting surfaces, such as a darkened film-projection room, the audience should be covered by direct path infra-red radiation from radiators positioned in front. When the direction of the receiver changes, e.g. with varying seat arrangements, mount the radiators in the corners of the room (see figure 1.15).

If the audience is always directed towards the radia- tors, you do not need radiators at the back

(see figure 1.16).

If the path of the infra-red signals is partially blocked, e.g. under balconies, you should cover the ‘shaded’ area with an additional radiator (see figure 1.17).

The figures below illustrate the positioning of the radiators:

Figure 1.16 Radiator positioning in a conference hall with

auditorium seating and podium

Figure 1.17 Radiator for covering seats beneath a balcony

1.3.6Overlapping footprints and multipath effects

When the footprints of two radiators partly overlap, the total coverage area can be larger than the sum of the two separate footprints. In the overlap area the sig- nal radiation power of two radiators are added, which increases the area where the radiation intensity is larg- er than the required intensity.

However, differences in the delays of the signals picked up by the receiver from two or more radiators can result in that the signals cancel each other out (multi path effect). In worst-case situations this can lead to a loss of reception at such positions (black spots).

Figure 1.15 Radiator position for covering seats in a square

arrangement

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