Abstract:
A wireless communication method and apparatus for decoding enhanced dedicated channel (E-DCH) absolute grant channel (E-AGCH) transmissions are disclosed. A wireless transmit/receive unit (WTRU) receives E-AGCH data which includes a cyclic redundancy check (CRC) part and a data part. The CRC part is masked with a WTRU identity (ID) at a Node-B. The CRC part and the data part are demultiplexed and the CRC part is demasked with the WTRU ID. A CRC is then performed with the demasked CRC part. If the CRC passes the data part is sent to an enhanced uplink medium access control (MAC-e) entity. The WTRU ID may be a primary E-DCH radio network temporary identity (E-RNTI) or a secondary E-RNTI. When the E-AGCH data is transmitted over a 10 ms frame, if the CRC fails, E-AGCH data via subsequent subframe may be soft combined with the previous E-AGCH data.
Abstract:
A hybrid orthogonal frequency division multiple access (OFDMA) system including a transmitter and a receiver is disclosed. The transmitter includes a first spread OFDMA subassembly, a first non-spread OFDMA subassembly and a first common subassembly. The first spread OFDMA subassembly spreads input data and maps the spread data to a first group of subcarriers. The first non-spread OFDMA subassembly maps input data to a second group of subcarriers. The first common subassembly transmits the input data mapped to the first and second group of subcarriers using OFDMA. The receiver includes a second spread OFDMA subassembly, a second non-spread OFDMA subassembly and a second common subassembly. The second common subassembly processes received data to recover data mapped to the subcarriers using OFDMA. The second spread OFDMA subassembly recovers the first input data by separating user data in a code domain and the second non-spread OFDMA subassembly recovers the second input data.
Abstract:
A wireless communication system and method generates and shapes one or more three-dimensional control channel beams for transmitting and receiving signals. Each three-dimensional beam is directed to cover a particular coverage area and beam forming is utilized to adjust bore sight and beam width of the three-dimensional beam in both azimuth and elevation, and the three-dimensional control channel beam is identified. In another embodiment, changes in hot-zones or hot-spots, (i.e., designated high volume user coverage areas), are managed by a network cell base station having at least one antenna. Each of a plurality of wireless transmit/receive units (WTRUs) served by the base station use a formed beam based on one or more beam characteristics. When the coverage area is changed, the base station instructs at least one of the WTRUs to change its beam characteristics such that it forms a return beam concentrated on the antenna of the base station.
Abstract:
A method and system for uplink (UL) synchronization of an uplink transmission from a plurality of wireless transmit/receive units (WTRUs) to a Node-B in a code division multiple access (CDMA) system. A Node-B receives a transmission including a UL synchronization (SYNC_UL) sequence from a WTRU. A sampler samples the transmission at a sampling rate which is higher than a chip rate. The samples are down-sampled and the SYNC_UL sequence is detected at a lower rate. A first significant path location of the detected SYNC_UL sequence is determined, and based on the first significant path location, a final significant path location is determined. The final significant path location is quantized and UpPCHPOS is transmitted to the WTRU to adjust a UL transmission timing.
Abstract:
Symbols are to be recovered from signals received in a shared spectrum. Codes of the signals received in the shared spectrum are processed using a block Fourier transform (FT), producing a code block diagonal matrix. A channel response of the received signals is estimated. The channel response is extended and modified to produce a block circulant matrix and a block FT is taken, producing a channel response block diagonal matrix. The code block diagonal matrix is combined with the channel response block diagonal matrix. The received signals are sampled and processed using the combined code block diagonal matrix and the channel response block diagonal matrix with a Cholesky algorithm. A block inverse FT is performed on a result of the Cholesky algorithm to produce spread symbols. The spread symbols are despread to recover symbols of the received signals.
Abstract:
A circuit for use in a receiver receives a plurality of code division multiple access data signals simultaneously. Each data signal experiences a similar channel response. The circuit receives a combined signal over the shared spectrum in a time slot. The combined signal comprises the plurality of data signals. The combined signal is sampled at a multiple of a chip rate of the combined signal. The similar channel response is estimated. A channel response matrix or a channel correlation matrix is constructed based in part on the estimated channel response. A spread data vector is determined based in part on a fast Fourier transform (FFT) decomposition of a circulant version of the channel response matrix or channel correlation matrix. The spread data vector is despread to recover data from the matrix.
Abstract:
Joint detection is performed in a multi-user detector (MUD) using reduced length channel impulse responses and using interference cancellation (IC) in the dimension of delay spread as a whole, whereby several clusters of smaller delay spread are processed. Several clusters of real transmitted paths that are close to each other are grouped together and zeros that occur between the path cluster groups are discarded. Each cluster group has a much shorter delay spread and thus has smaller dimensions of system matrix A. Mutual interference occurring between the path cluster groups is eliminated by applying an interference cancellation technique.
Abstract:
A wireless time division duplex/code division multiple access user equipment measures an interference level in time slots. The interference measurements are transmitted. The transmitted interference measurements enable for each of a plurality of nearby user equipments potentially near the user equipment not in a cell of the user equipment to classify timeslots and to determine non-interfering and interfering ones of the nearby user equipments using the timeslots classifying. Communications are transmitted over timeslots assigned by a received timeslot assignment. The received timeslot assignment based on the determined non-interfering and interfering ones of the nearby user equipments. The received timeslot assignment is received. Communications are received over timeslots assigned by the received timeslot assignment.
Abstract:
A time division duplex using code division multiple access user equipment receives a plurality of data signals in a time slot. Each data signal experiences a similar channel response. The user equipment receives a combined signal over the shared spectrum in a time slot. The combined signal comprises the plurality of data signals. The combined signal is sampled at a multiple of a chip rate of the combined signal. The similar channel response is estimated. A channel response matrix or a channel correlation matrix is constructed based on in part the estimated channel response. A spread data vector is determined based on in part a fast fourier transform (FFT) decomposition of a circulant version of the channel response or channel correlation matrix. The spread data vector is despread to recover data from the matrix.
Abstract:
Symbols are to be recovered from signals received in a shared spectrum. Codes of the signals received in the shared spectrum are processed using a block Fourier transform (FT), producing a code block diagonal matrix. A channel response of the received signals is estimated. The channel response is extended and modified to produce a block circulant matrix and a block FT is taken, producing a channel response block diagonal matrix. The code block diagonal matrix is combined with the channel response block diagonal matrix. The received signals are sampled and processed using the combined code block diagonal matrix and the channel response block diagonal matrix with a Cholesky algorithm. A block inverse FT is performed on a result of the Cholesky algorithm to produce spread symbols. The spread symbols are despread to recover symbols of the received signals.