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FIGURE 7.5
Disruption time versus M.
≤
In addition, PHS still outperforms L2 as M 100 (largest number of MSSs) due to the effect of the appropriate centralized management in SBS. This scheme will avoid useless handover processes and transform useless messages to MSSs, which will get lower disruption times. The saving time is achieved by precoordination of reauthorization and reregistration with the TBS and remitting the time of ranging with the TBS. Therefore, the service DT of PHS is less than any other handover schemes.
7.7 Conclusion
In this chapter, we investigated a measured signal-aware mechanism for BS, which periodically monitors on moving MSSs and prepares CDMA rang- ing code for handover use beforehand. Simulation results show that PHS decreases the average service DT of the WiMAX as well as lowers han- dover failure probability of MSSs efficiently even in highly competitive circumstance. Through the derived system model expression, we present the PHS scheme to improve the lower TDT by close to 40 ms without changing the standard IEEE 802.16e standard. Specifically, in our proposed solutions the MAC protocol at both the BS and MSS do not need to be mod- ified and are readily disposable over the existing network infrastructure.
Simulations show that the PHS system model confirms the analytical results. Moreover, by considering the mobility of MSSs, the PHS scheme can be investigated further for supporting QoS among macrocells.
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802.16 Mesh Networking
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