Patent ID: 7925263
Filing Date: 2011-04-12
Classification: H04W

Abstract:
1. A method for triggering a handoff by a wireless transmit/receive unit (WTRU) from a current basic service set (BSS) in a wireless local area network (WLAN), comprising: determining a highest class of traffic service and quality of service (QoS) for the highest class from a basic service set (BSS) beacon; terminating a handoff and retaining communication with the current BSS when the signal to noise ratio (SNR) or received signal strength (RSS) is greater than a high threshold of the highest class; calculating a quality of service (QoS) index by: determining a QoS index difference value between the selected BSS and the current BSS and comparing the QoS index difference value with a hysteresis; updating the hysteresis value on a condition that the QoS index difference value is smaller than the hysteresis; defining a minimum and maximum value of delay bounds, bandwidth requirements, and frame error rate for a plurality of traffic classes; and evaluating the delay bounds, bandwidth requirements, and frame error rate to determine whether a handoff is desired when the SNR or RSS is less than the high threshold.