A method and apparatus for allocating subcarriers in an orthogonal frequency division multiple access (OFDMA) system is described. In one embodiment, the method comprises allocating at least one diversity cluster of subcarriers to a first subscriber and allocating at least one coherence cluster to a second subscriber.

Ofdma with adaptive subcarrier-cluster configuration and selective loading

Disclosed is a method and system for dynamically selecting a communication channel between an access point (AP) and a plurality of stations (STAs) in an IEEE 802.11 wireless local area network (WLAN). The method includes the steps of: determining whether a new channel to be used by the plurality of STAs is needed; measuring the channel quality of a plurality of frequency channels by at least one of the plurality of STAs; reporting the quality of the plurality of frequency channels in terms of a received signal strength indication (RSSI), Clear Channel Assessment (CCA) busy periods and periodicity; and, selecting one of the candidate channels based on the channel quality report for use in communication between the AP and the plurality of STAs.

DYNAMIC FREQUENCY SELECTION SCHEME FOR IEEE 802.11 WLANs

A method and apparatus for subcarrier selection for systems is described. In one embodiment, a method for subcarrier for a system employing orthogonal frequency division multiple access (OFDMA) comprises partitioning subcarriers (101) into groups of at least one cluster of subcarriers (102), receiving an indication of a selection by the subscriber of one or more groups (103) in the groups, and allocating at least one cluster in the one or more groups of clusters selected by the subcarrier for use in communication with the subscriber (104, 105).

Multi-carrier communications with group-based subcarrier allocation

A dual mode cellular cordless portable radiotelephone preferentially selects the cordless base station over the cellular system when in range of the cordless base station. When the cordless cellular portable is operating in the cellular mode, the radio channel associated with the cordless base station is sampled for a predetermined time. When a signal on the sampled cordless base station channel is detected, the cordless portable moves to the cordless mode and remains in the cordless mode for as long as the signal quality of the signal on the cordless base station channel exceeds a predetermined value.

Apparatus and method for alternative radiotelephone system selection

Multi-carrier communications with adaptive cluster configuration and switching

A base station (21, 22, 23) in a radio communication system (20) comprises a channel allocator (62) for allocating communication channels by accessing a Preferred Channel List (PCL) (64). The PCL ranks channels (116) in accordance with the occurrence of prior events on the channels (112), such as interrupted calls (122), blocked call setup requests (118), and calls successfully completed (106) and in regards to the mean quality margin (110) and the current channel quality (114). The channel allocator (62) allocates (140) the first available channel (128) in the PCL having a free timeslot (132) and with good current channel quality (136).

Method and apparatus for dynamic channel allocation.

A handset (24, 25) in a radio communication system (20) determines the quality of a channel (500 and 502) in response to an RSSI signal generated by a receiver (174) in combination with either an eye closure measurement (510) or a bit error rate detected by a CRC codeword in received digital information (502). The battery operated handset is also capable of conserving scanning power while operating in an area having high channel quality (520, 560, 566). The handset also has a method for determining the amount of handovers between base stations (21, 22, 23) by use of dual channel quality thresholds (582, 590) which require a higher quality threshold for establishing communication with a base station and a reduction in channel quality before a handover to a new base station.

Zhonghe Wang

Papers

Method and apparatus for dynamic channel allocation.

Hanset for a multiple channel communication system and use thereof

Method and apparatus for cynamic channel allocation