Avaya DECT R4 Installation Manual page 20

2. Site Survey and Planning
We cannot give precise recommendations for a site survey as every site will vary. However a site survey is a prerequisite
to installation in all cases. The correct and effective placement of base stations will prevent problems and maximize
coverage. Most issues with any DECT system will arise from the number and positioning of the base stations.
The basic aim is to ensure:
· Base station coverage in all areas of expected DECT phone usage.
· Sufficient number of base stations covering each area for the number of expected simultaneous users (up to 8 per
base station) in that area.
· Sufficient overlap between areas of base station coverage to allow for
are moving.
· Where possible, synchronization
The diagram below indicates the basic measures for coverage between a base station and a DECT phone.
Signal Description
Strength
-40dB Strong signal typically seen when a phone is close to the base station.
-62dB Minimum signal strength at which a base station will accept a phone wanting to handover from another base
station.
-68dB Signal strength below which the phone will begin looking for a base station to which it can handover.
-75dB At this signal strength, the increase error rate will become apparent in the speech.
-90dB At this signal strength calls are likely to disconnect.
Though this section focuses mainly on the measure of signal strength, the DECT signalling employs a number of methods
to overcome a poor signal. The other key factor that affects signalling is the error rate. While decreasing signal strength
and increasing error rate are usually related, there may be some scenarios where a high than expect error rate occurs.
DECT R4
IP Office Release 7.0
of each base station with more than one other base station.
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call handover when DECT phone users
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15-601047 Issue 03a (21 February 2011)
Page 20