Poor Radio Performance

If the radio environment is poor there is a higher likelihood that the base station will timeout on some of the messages sent to the cabs.  This occurs when the base station has tried to send the message 8 times for a RB01, or 16 times for a RB02.  When a timeout occurs the message gets trapped in a buffer in the
RB02 and that associated buffer space becomes unusable.   The RB02 has a finite amount of buffer space and each trapped message reduces the usable buffer space.  
In normal radio environments very few messages time out so this has very little affect on performance.  If your system is in a less than ideal radio environment (weak reception, interference, pre. V1.5 cabs) you are likely to have more message timeouts.  Each timeout reduces the usable buffer space and over time the shrinking buffer space can cause the radio performance and response time to slow down.  This
is a reason why the radio performance may appear to slow down over long operating sessions.

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