Abstract: A method and apparatus is provided for transmitting an orthogonal frequency domain multiple access (OFDMA) signal including a synchronization channel signal transmitted within a localized portion of a bandwidth of the OFDMA signal, the synchronization channel signal having predetermined time domain symmetry within the localized portion of the bandwidth and including information for providing at least partial cell identification information. The synchronization channel signal enables an initial acquisition and cell search method with low computational load which provides OFDMA symbol timing detection and frequency error detection and frame boundary detection and cell specific information detection in an OFDMA system supporting multiple system bandwiths, both synchronized and un-synchronized systems, a large cell index and an OFDMA symbol structure with both short and long cyclic prefix length.

Abstract: During operation radio frames are divided into a plurality of subframes. Data is transmitted over the radio frames within a plurality of subframes, and having a subframe type selected from a plurality of subframe types. Each subframe type having a same time duration and being distinguished by having a differing number of OFDM symbols or a differing number of single carrier FDMA symbols.

Abstract: Communications sourced by a remote unit (14) that is already within reception range of a base site (10) can nevertheless be further facilitated through allocation of one or more relay resources (15, 16). Such relay resources, properly employed, then serve to effectively increase the quality of service for the facilitated communication. This, in turn, can permit the use of, for example, increased data rates for communications from a relatively low power remote unit.

Abstract: A method and apparatus are provided for indicating to a communication unit a plurality of modulation and coding schemes (MCSs) to be utilized for communication. During a first MCS is determined for first resource blocks to be sent to a first remote unit or base station, and a second MCS is determined for a second resource block to be sent to the remote unit or base station. A message is transmitted indicating the first and the second MCS and also indicating the first resource blocks and the second resource block. Finally, a first PDU is transmitted to the remote unit or base station at a first time using the first MCS and the first resource blocks and a second PDU is transmitted to the remote unit or base station at the first time using the second MCS and the second resource block.

Abstract: A method and apparatus is provided for transmitting an orthogonal frequency domain multiple access (OFDMA) signal including a synchronization channel signal transmitted including a plurality of sequence elements interleaved in time and frequency. The synchronization channel signal sequence elements enable an initial acquisition and cell search method with low computational load by providing predetermined time domain symmetry for common sequence elements in OFDMA symbol periods for OFDMA symbol timing detection and frequency error detection in an OFDMA system supporting multiple system bandwidths, both synchronized and un-synchronized systems, a large cell index and an OFDMA symbol structure with both short and long cyclic prefix length.

Abstract: Frequency hopping in an IFDMA system takes place by utilizing a time-varying IFDMA modulation code. In particular, a modulator receives a symbol stream and a user specific IFDMA modulation code (bi(t)). The output of the modulator comprises a signal (xi(t)) existing at certain frequencies, or subcarriers. The actual subcarriers that signal xi(t) utilizes is dependent upon the repetition of the symbol blocks and the particular IFDMA modulation code utilized.

Abstract: A method and apparatus for performing spatial-division multiple access within a communication system is provided herein. During operation, nodes will return null subspace information along with their channel subspace information. The null subspace is similar to the channel subspace except that the null subspace information directs a base station to the matrix in a predefined codebook that results in minimum power being received at the node. The null subspace for each node is taken into consideration when communicating with a particular node.

Abstract: A method and apparatus is provided for transmitting an orthogonal frequency domain multiple access (OFDMA) signal including a synchronization channel signal transmitted within a localized portion of a bandwidth of the OFDMA signal (818), the synchronization channel signal having predetermined time domain symmetry within the localized portion of the bandwidth (816) and including information for providing at least partial cell identification information (812). The synchronization channel signal enables an initial acquisition and cell search method with low computational load which provides OFDMA symbol timing detection and frequency error detection (1112) and frame boundary detection and cell specific information detection (1114) in an OFDMA system supporting multiple system bandwidths, both synchronized and un-synchronized systems, a large cell index and an OFDMA symbol structure with both short and long cyclic prefix length.

Abstract: A method and apparatus are provided for indicating to a communication unit a plurality of modulation and coding schemes (MCSs) to be utilized for communication. During a first MCS is determined for first resource blocks to be sent to a first remote unit or base station, and a second MCS is determined for a second resource block to be sent to the remote unit or base station. A message is transmitted indicating the first and the second MCS and also indicating the first resource blocks and the second resource block. Finally, a first PDU is transmitted to the remote unit or base station at a first time using the first MCS and the first resource blocks and a second PDU is transmitted to the remote unit or base station at the first time using the second MCS and the second resource block.

Abstract: A method and apparatus is provided for transmitting an orthogonal frequency domain multiple access (OFDMA) signal including a synchronization channel signal transmitted including a plurality of sequence elements interleaved in time and frequency (610, 640). The synchronization channel signal sequence elements enable an initial acquisition and cell search method with low computational load by providing predetermined time domain symmetry (702, 704) for common sequence elements in OFDMA symbol periods (620, 660) for OFDMA symbol timing detection and frequency error detection in an OFDMA system supporting multiple system bandwidths, both synchronized and un-synchronized systems, a large cell index and an OFDMA symbol structure with both short and long cyclic prefix length.

Abstract: A determination of link quality (CSR) is made from the subscriber station to a relay station. A determination of link quality (CRB) is made from the relay station to the base station, and a determination of link quality (CSB) is made from the subscriber station to the base station. A quality of a first link path from the subscriber station to the base station that passes through the relay station is determined based on at least the link qualities (Csr, Crb). A quality of a second link path from the subscriber station to the base station that does not pass through the relay station is determined based on at least the link quality (Csb). Finally, a determination is made whether to utilize the first link path or the second link path from the subscriber station to the base station based on at least the quality of the first and second link paths.

Abstract: A determination of link quality (CSR) is made from the subscriber station to a relay station. A determination of link quality (CRB) is made from the relay station to the base station, and a determination of link quality (CSB) is made from the subscriber station to the base station. A quality of a first link path from the subscriber station to the base station that passes through the relay station is determined based on at least the link qualities (Csr, Crb). A quality of a second link path from the subscriber station to the base station that does not pass through the relay station is determined based on at least the link quality (Csb). Finally, a determination is made whether to utilize the first link path or the second link path from the subscriber station to the base station based on at least the quality of the first and second link paths.

Abstract: A pilot (or reference) transmission scheme is utilized where different transmitters are assigned pilot sequences with possibly different cyclic time shifts. A pilot signal is transmitted concurrently by the transmitters in a plurality of pilot blocks, and a receiver processes the plurality of received pilot blocks to recover a channel estimate for at least one of the transmitters while suppressing the interference due to the pilot signals from the other transmitters.

Abstract: A determination of link quality (CSR) is made from the subscriber station to a relay station. A determination of link quality (CRB) is made from the relay station to the base station, and a determination of link quality (CSB) is made from the subscriber station to the base station. A quality of a first link path from the subscriber station to the base station that passes through the relay station is determined based on at least the link qualities (Csr, Crb). A quality of a second link path from the subscriber station to the base station that does not pass through the relay station is determined based on at least the link quality (Csb). Finally, a determination is made whether to utilize the first link path or the second link path from the subscriber station to the base station based on at least the quality of the first and second link paths.

Abstract: In a wireless communication system, a method and apparatus for closed loop transmission is disclosed. In accordance with the preferred embodiment of the present invention, a time frequency portion of an uplink frame is dynamically reserved as a sounding zone for uplink channel sounding. A first message is transmitted to a first subscriber station in a downlink frame assigning a time-frequency resource within the sounding zone, and a sounding waveform. Furthermore, a signal is received from the subscriber station within the assigned time-frequency resource, a partial channel response is determined from the received sounding signal, and the subsequent transmission to the subscriber station is tailored based on the at least partial channel response.

Abstract: A method (300, 400, 500, 600) of communicating with a subscriber station (102). Responsive to determining that a supplemental communication link with the subscriber station is desirable, at least a second access point (106, 108, 110, 112, 114, 116) can be identified to establish the supplemental communication link with the subscriber station. Information can be communicated to the second access point. The information can identify the subscriber station and a pilot zone in which downlink supplemental data is to be transmitted from the second access point to the subscriber station. Downlink supplemental data (150) also can be communicated to the second access point. The downlink supplemental data can improve integrity of data transmitted from a first access point (104) to the subscriber station when the downlink supplemental data is transmitted to the subscriber station from the second access point.

Abstract: A method and apparatus is provided for transmitting an orthogonal frequency domain multiple access (OFDMA) signal including a synchronization channel signal transmitted within a localized portion of a bandwidth of the OFDMA signal (818), the synchronization channel signal having predetermined time domain symmetry within the localized portion of the bandwidth (816). The synchronization channel signal enables an initial acquisition and cell search method with low computational load which provides OFDMA symbol timing detection and frequency error detection by differential processing of sequence elements of the synchronization channel signal (1112) and frame boundary detection and cell specific information detection (1114) in an OFDMA system supporting multiple system bandwidths, both synchronized and un-synchronized systems, a large cell index and an OFDMA symbol structure with both short and long cyclic prefix length.

Abstract: A method for communicating a plurality of data streams between a transmitting device with multiple transmit antennas and a receiving device, is disclosed. The method comprises determining a list consisting of a subset of the multiple transmit antennas on which the transmitting device will transmit data, determining a set of power weightings, providing the set of power weightings and the list of the subset of the multiple transmit antennas to the transmitting device, weighting a plurality of data streams by the power weightings, and transmitting the power weighted data streams on the subset of the multiple transmit antennas to the receiving device. Another aspect of the invention comprises maintaining a codebook consisting of a plurality of transmit weight vectors at both the transmitting device and the receiving device.

Abstract: In a wireless communication system, a method and apparatus for reference signal selection is disclosed. In accordance with the preferred embodiment of the present invention, a first reference signal in a first cell is pseudo-randomly selected from a predetermined limited set of reference signals for transmission on a first channel resource. A second reference signal in the cell is pseudo-randomly selected from the predetermined limited set of reference signals for transmission on a second channel resource, where the predetermined limited set of reference signals is common among the first cell and at least a second cell.

Abstract: Receiving units will switch between performing a DC bias suppression and not removing the DC distortion at the receiver depending on the amount of DC interference level observed/measured/estimated. Since the overall DC interference is from all uplink transmitters, potentially at different power levels, the amount of DC distortion can be measured based on the difference between the received power level and the expected power level on the DC sub-carrier. Additionally it can be estimated based on the number of active transmitters, their allocation bandwidth, power control target and/or a rough estimate of the DC distortion introduced by each active transmitter and also the distortion introduced by the receiver. Once this distortion level is estimated, a decision is then made whether or not to remove the DC distortion.