There are numerous delay's associated with wireless communication. For example, I have found in many literature's that there is a delay of 3 (Transmission-time interval) TTI for channel quality index (CQI) feedback and depending upon the CQI the data rate of a user is determined. But if the delay exceeds this, should the BS wait continuously, resend any kind of signal or drop the user?
It also includes Transmission Delay, Propagation Delay. However, BS will be getting/passing some signals to mobile nodes. So, BS will not be waiting anymore. If BS drops the users, he/she wont get satisfaction with the service provider. Classify the users according to their application what they use.
You need to apply Erlang B formula here. It is like an exponential distribution where quantities like no. of calls per hr and average time for a call are used. Look into Chapter 2 of Rappaport book on Wireless communications.
In any FDD system, the system allows a maximum delay between sending of command and its decoding at the other end. In GSM system, the delay allowed is 3 time slots.
If the link cannot be established in this time, the base station drops the call. The initiating party has to call the required party once more.
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