1x Evolution-Data Optimized Revision A (1xEV-DO Rev. A) is a cellularcommunications standard that introduces key enhancements to the high data rate packetswitched 1xEV-DO Release 0 standard. The enhancements are driven by the increasingdemand on some applications that are delay sensitive and require symmetric data rateson the uplink and the downlink. Some examples of such applications being videotelephony and voice over internet protocol (VoIP).The handoff operation is critical for delay sensitive applications because themobile station (MS) is not supposed to lose service for long periods of time. Thereforeseamless server selection is used in Rev. A systems. This research analyzes theperformance of this handoff technique. A theoretical approach is presented to calculatethe slot error probability (SEP). The approach enables evaluating the effects of filtering,hysteresis as well as the system introduced delay to handoff execution. Unlike previousworks, the model presented in this thesis considers multiple base stations (BS) andaccounts for correlation of shadow fading affecting different signal powers receivedfrom different BSs. The theoretical results are then verified over ranges of parameters ofpractical interest using simulations, which are also used to evaluate the packet error rate(PER) and the number of handoffs per second. Results show that the SEP gives a good indication about the PER. Results alsoshow that when considering practical handoff delays, moderately large filter constantsare more efficient than smaller ones.
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