A CDMA-assisted seamless handover scheme for WLAN

With the development of WLAN (Wireless Local Area Network) technologies, many hotspots have been deployed and mobile devices can get Internet services through WLAN in many places. Some schemes based on the RSS (Receive Signal Strength) have been proposed to provide the seamless handover between WLANs. However, they can not avoid the ping-pong effect, and the handover performance is always influenced, especially when the handover is performed between adjacent cells which are not overlapping with each other very well. So in this paper, we propose a CDMA-assisted handover scheme (CAHO) for WLAN, which uses the CDMA connection during the handover. To evaluate the performance of CAHO, we set up a test-bed and compare it with other schemes. The experimental results show that the CAHO can reduce disruptions and lost packets. Furthermore, it can avoid the ping-pong handovers effectively.