Abstract:
A method for determining whether a connection event between a base station and a wireless transmit/receive unit (WTRU) should be accepted or rejected (151), comprises measuring the interference level Io in a candidate timeslot; measuring the path loss L between the base station and the WTRU; measuring the total transmit power P0 of the base station; determining a thermal noise level theta; determining a fading average signal-to-interference ratio (SIR); and calculating a ratio R (141), wherein if the ratio R (152 or 157) is above a certain threshold the connection event will be accepted and if the call is below the threshold it will be rejected.
Abstract:
A method and communication system (e.g., TDD system) that uses adaptive antennas at the base stations to monitor metrics associated with the quality of one or more CPCH timeslots, so as to determine whether to reuse some or all of the CPCH timeslots to transmit the DPCH. If it is determined to reuse some or all of the CPCH timeslots, an additional determination is made as to what limit to apply on the DPCH transmission powers. Adaptive antennas may be used at the base stations to allow the system to reuse some or all of the CPCH timeslots to transmit DPCH, thus improving the overall capacity of the system while maintaining the CPCH coverage and quality at a desired level throughout the system.
Abstract:
A method for increasing cellular system capacity includes receiving a signal in a time slot and a frequency band and transmitting a signal in the same time slot and the same frequency band. An adaptive self-interference canceller (120) is used to reduce the radio frequency self-interference created by receiving and transmitting signals in the same time slot and the same frequency band. The self-interference can be further reduced by using: a circulator (104) connected between an antenna (102), a receiver (114), and a transmitter (118); separate antennas for receiving and transmitting signals can be used; and/or an adaptive antenna.
Abstract:
A method and apparatus for adjusting a channel quality indicator (CQI) feedback period to increase uplink capacity in a wireless communication system are disclosed. The uplink capacity is increased by reducing the uplink interference caused by CQI transmissions. A wireless transmit/receive unit (WTRU) monitors a status or downlink transmissions to the WTRU and sets the CQI feedback period based on the status of the downlink transmissions to the WTRU. A base station monitors uplink and downlink transmission needs. The base station determines the CQI feedback period of at least one WTRU based on the uplink and downlink transmission needs and sends a command to the WTRU to change the CQI feedback period of the WTRU.
Abstract:
A deferral management method is implemented in a wireless local area network (WLAN) including an access point (AP) and a plurality of wireless transmit/receive units (WTRUs). The AP sends a deferral management capabilities request message to the WTRUs to determine the deferral management capabilities of the WTRUs. In response, each of the WTRUs sends a deferral management capabilities indicator message to the AP. The AP may also send a deferral management parameter set message to the WTRUs to indicate values for setting deferral management parameters. In response, each of the WTRUs may optionally send a deferral management parameter set execution confirmation message to the AP. The WTRUs may also set the values of various deferral management parameters in accordance with a certain rule specified in a deferral management rule message sent by the AP. Optionally, the WTRUs may respond to the AP with a deferral management rule execution confirmation message.
Abstract:
In a wireless local area network having an access point (AP) and at least one station, wherein data is prioritized by access categories, a method for admission control begins by calculating a transmission budget for each access category (AC) and a total transmission budget for all Acs requiring admission control. A traffic stream admission request is sent from a station to the AP. A medium time value for the traffic stream is calculated at the AP, based on information extracted from the admission request. The medium time value is compared to the transmission budget for the AC corresponding to the traffic stream and the total transmission budget. The traffic stream is accepted if the medium time value is not greater than both the transmission budget for the AC corresponding to the traffic stream and the total transmission budget; otherwise, the traffic stream is rejected.
Abstract:
A method for neighbor scanning in a wireless local area network having a station, a first access point, AP, to which the station is associated, and a second AP, comprising the steps of generating timing information regarding a beacon signal sent by the second AP, reporting the timing information from the first AP to the station and scheduling at the station a time, based on the timing information, to listen for the beacon signal transmitted by the second AP. The timing information includes an indication of a time difference between a second beacon signal sent by the access point and the first beacon signal sent by the second AP and the time difference is an offset in timing units.
Abstract:
A system and method to optimize the number of uplink and downlink slots, given the maximum number of crossed slots between any two cells is disclosed. The present invention effectively assigns a direction (i.e. uplink or downlink) to every slot in every cell of the system, taking into account the trade-off between: a) avoiding base-to-base or mobile-to-mobile interference; and b) matching the slot assignment of every cell as closely as possible to the local traffic conditions. The present invention assigns users to slots according to their transmission power requirements in order to allow conflicting slot-to-cell assignments between two cells in the same geographic region.