In IEEE 802.16, one of the main features is the QoS-Provisioning.
The limited bandwidth and the increasing of the high data rate service
users will impact the performance of the system. In this study, we propose
a VHO algorithm that can support the provisioning of QoS in mobile WiMAX
networks by handing over some Best-Effort (BE) low-speed WiMAX Subscriber
Station (SS) to an overlaid WLAN network subject to the QoS guarantee
for the SS. Our simulation results show that by utilizing the overlaid
WLAN hotspots we can gain some free band for the new SS requests. According
to our simulation results a significant improvement in the capacity and
the probability of blocking (PB) in WiMAX network was achieved.