The object is achieved by providing a base station apparatus for performing time and frequency scheduling in uplink packet access with: an interference amount measurement part configured to measure an uplink interference amount for each interference amount measurement unit which comprises a predetermined period and a predetermined number of frequency blocks; an interference amount determination part configured to determine whether the uplink interference amount satisfies a predetermined condition; and an overload indicator reporting part configured to report an overload indicator to a neighboring cell when the predetermined condition is satisfied.

Base station apparatus and communication control method

Beam selection is provided. A method for handover in a mobile station includes sending a scan request message for scanning a downlink (DL) beam with respect to a serving base station (BS) and a neighboring BS, to the serving BS, and receiving a scan response message; determining the DL beam for the MS by performing scanning with the serving BS and the neighboring BS based on the scan response message; sending a scan report message comprising a result of the scanning to the serving BS; when receiving an air-HO request message from the serving BS, generating an air-HO response message comprising information of a neighboring BS to which the MS hands over based on the air-HO request message; performing beam selection with the neighboring BS of the handover based on the air-HO request message; and performing the handover.

Method and apparatus for short handover latency in wireless communication system using beam forming

Pilot signal transmission sequences and methods are described for use in a multi-sector cell. Pilots in different sectors are transmitted at different known power levels. In adjacent sectors a pilot is transmitted while no pilot is transmitted in the adjoining sector. This represents transmission of a NULL pilot signal. A cell NULL is also supported in which NULL pilots are transmitted in each sector of a cell at the same time. Multiple pilot signal measurements are made. At least two channel quality indicator values are generated from measurements corresponding to at least two pilot signals of different power levels. The two values are transmitted back to the base station which uses both values to determine the transmit power required to achieve a desired SNR at the wireless terminal. The wireless terminal also reports information indicating its location to a sector boundary.

Pilot signals for use in multi-sector cells

Techniques for sending information in a wireless network are described. The network may support (i) regular subframes used to send unicast information and (ii) multicast/broadcast single frequency network (MBSFN) subframes used to send broadcast information and having lower overhead than the regular subframes. In an aspect, MBSFN subframes may be used to mitigate interference. A first base station may cause high interference to stations (e.g., UEs) served by a second base station. The first base station may reserve a subframe for the second base station, send system information conveying the reserved subframe as an MBSFN subframe to its stations, and transmit in a first part of the reserved subframe in accordance with an MBSFN subframe format. The second base station may skip the first part and may send unicast information to its stations in the remaining part of the reserved subframe. In another aspect, MBSFN subframes may be used to support additional base station capabilities.

Method and apparatus for using mbsfn subframes to send unicast information

In an overlay, U-TDOA-based, Wireless Location System, LMUs typically co-located with BTSs, are used to collect radio signaling both in the forward and reverse channels. Techniques are used to compensate for sparse LMU deployments where sections of the U-TDOA service area are uplink demodulation or downlink beacon discovery limited.

Sparsed U-TDOA wireless location networks

A method for supporting handover in a BWA communication system is provided. The system includes an MS, a serving BS, and a plurality of neighbor BSs. The coverage area of each of the BSs is divided into sectors using different subcarrier bands. The MS collects information broadcast from the serving BS on the serving BS and the neighbor BS, measures a signal level for each of the sectors of the serving BS and the neighbor BSs according to the collected information, and sends a handover request based on the measured signal level for each of the sectors. The serving BS broadcasts information on the serving BS and the neighbor BS to the MS, determines if the MS can perform a soft handover from its current sector to another sector upon receiving the handover request from the MS, and permits the MS to perform the soft handover if possible.

System and method for supporting soft handover in a broadband wireless access communication system

Disclosed is a system and a method for controlling a handover of a mobile subscriber station in a broadband wireless access communication system. When serving base station determines to perform a handover of the mobile subscriber station, neighbor base stations to which the mobile subscriber station can be handed over, from among neighbor base stations of the mobile subscriber station, are determined based on a service quality level of service being currently provided to the mobile subscriber station. A handover request signal containing information related to the determined neighbor base station to which the mobile subscriber station can be handed over is transmitted to the mobile subscriber station. The serving base station receives from the mobile subscriber station in response to the request of the handover information about one neighbor base station to which the mobile subscriber station will be handed over, and informs the neighbor base station that the mobile subscriber station will be handed over to the neighbor base station.

System and method for performing handover in a broadband wireless access communication system

A method for allocating a band Adaptive Modulation and Coding (AMC) channel in a wireless communication system that divides a full frequency band into a plurality of subcarrier bands and includes subchannels, each of which is a set of a predetermined number of neighbor subcarrier bands. Upon recognizing a need for a band AMC channel, a subscriber station (SS) sends a request for allocation of the band AMC channel to a base station (BS). Upon receiving the band AMC channel allocation request, the BS determines if it can allocate the band AMC channel requested by the SS, considering a resource situation of the BS, and transmits information on the determination to the SS.

System and method for managing a band AMC subchannel in an orthogonal frequency division multiple access communication system

A method for transmitting a traffic indication message for directing a mobile subscriber station (MSS) in a sleep mode to transition to an awake mode in a Broadband Wireless Access communication system supporting the sleep mode and the awake mode. This method includes the steps of individually allocating, to MSSs belonging to a corresponding base station, corresponding areas indicating traffic instructions for the MSSs in a traffic indication field in the traffic indication message, and indicating state transition instructions in the areas allocated to the MSSs, before transmitting the traffic indication message to the MSSs.

Method for transmitting a traffic indication message in a broadband wireless access communication system

A system and method for transmitting a traffic indication message in a Broadband Wireless Access communication system. A base station (BS) transmits the traffic indication message to mobile subscriber stations (MSSs). The traffic indication message includes information on a number of MSS groups and information on a number of traffic indication indexes, each of the MSS groups includes a predetermined number of MSSs, and each of the traffic indication indexes is assigned to each of the MSS groups, and includes a bitmap including a predetermined number of bits. The predetermined number of bits is identical to the number of the MSSs included in each of the MSS groups, each of the predetermined number of the bits is assigned to each of the MSSs included in each of the MSS groups, and represents operation instruction information for each of the MSSs.

Yeong Moon Son

Papers

System and method for supporting soft handover in a broadband wireless access communication system

System and method for performing handover in a broadband wireless access communication system

System and method for managing a band AMC subchannel in an orthogonal frequency division multiple access communication system

Method for transmitting a traffic indication message in a broadband wireless access communication system

System and method for transmitting and receiving a traffic indication message in a broadband wireless access communication system