MS-initiated Handover Decision Criteria for VoIP over IEEE802.16e

摘要

The emerging mobile WiMAX (IEEE802.16e) has gained serious attention as a means of providing broadband wireless access to mobile users. The 802.16e supports high data rates and QoS for various applications, and is thus a powerful contender for next generation wireless access technology. On the other hand, IEEE 802.11 a/b/g/n have already been widely used to provide high data rates in a limited area. Therefore, in the near future, 802.16e and 802.11 will co-exist and a multi-homed mobile station (MS) will be likely to execute many handovers due to free movement among 802.16e's hotzones and 802.11's hotspots. So far, many studies of HO decision criteria for 802.11 have been conducted but an HO decision criteria for 802.16e have not yet been sufficiently studied, in particular HO decision criteria for MS-initiated HO. In this paper, we propose MS-initiated HO decision criteria for VoIP over 802.16e considering wireless link condition and congestion state of the 802.16e network, i.e., CINR and MS queue length. Our simulation results showed that the combined use of MS queue length and CINR can be proper MS-initiated HO decision criteria for VoIP over 802.16e.