Avaya CS 1000, Основы

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Figure 4: Signal strength considerations
• An open area has more than sufficient signal strength for synchronization. The expected
level at the double distance is --78 dBm. The required level is --80 dBm to --85 dBm. This
leaves a safely margin of 2 to 7 dB.
• Obstructions between the DAPs can introduce loss. Also, many objects cause reflections
that let the signal reach the DAPs through other path with sufficient signal strength.
• In rare cases, factors in the surrounding environment can cause the error rate in the
received frames to be temporarily much higher than is normal for speech. An occasionally
elevated error rate does not indicate a problem with your SIP DECT system. However, if
you consistently see a high error rate, then there is a problem with the deployment of your
SIP DECT system.
Frame errors:
Frame errors rarely can occur in DECT. The number of frame errors for each reading may not
be more than four. The most common cause of frame errors higher than four is a high number
of reflections. This causes an audible click during calls.
IP network configuration
The IP network must be able to support SIP DECT; this section provides information about
planning an IP network that is suitable for supporting SIP DECT.
SIP DECT typically uses existing IP network infrastructure and facilities for the network
connection. For IP connectivity, you must configure the network to ensure that all SIP DECT
components have the following characteristics:
• are equipped with unique IP addresses (some static, some dynamic)
• can reach all the required services
• can be reached by all clients and counterparts
Components of SIP DECT systems
SIP DECT Fundamentals October 2012 23