Tait TB9100, Инструкция по установке и эксплуатации

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108 Technical Description TB9100 Installation and Operation Manual
© Tait Electronics Limited May 2006
Re-voting
If base stations are configured for a common input frequency, multiple base
stations can receive the same terminal stream. If the receiver fades at the vote
winner, another base station may have a better signal, and should take over.
With a common frequency, multiple base stations will often start calls at
approximately the same time, however, the normal voting rules will select
the best stream.
Re-voting takes place every 180 ms, when all base stations select the best
stream available, and transmit it until the next re-vote. If the winning
receiver loses its signal entirely, it sends a fade message instead of the header
at the next re-vote. The fade message is an announcement that the base
station has lost the vote. All base stations receiving RF signal immediately
re-vote when they receive a fade message.
When voting, the voter sequences the packets from the voted streams so that
proper packet ordering is preserved. In particular, re-voting is transparent to
encryption.
Re-voting will not work if the cross-network delay is greater than 180 ms.
It is no longer possible to guarantee that all base stations are voting the same
signal.
Shared receiver frequency operation and repeater disable both increase the
network bandwidth requirements. With shared frequency, for the jitter
buffer to work properly, it needs to be set to the network delay plus the
network jitter allowance.