Abstract:
PROBLEM TO BE SOLVED: To provide systems and methods for an enhanced Multimedia Broadcast Multicast Service (MBMS) in a wireless communications network.SOLUTION: A number of base stations 24 in an MBMS zone 18, or a broadcast region, accommodate both Spatial Multiplexing (SM) enabled user elements 26 and non-SM enabled user elements 28. The number of base stations 24 form the MBMS zone 18, or broadcast region, where the MBMS zone is sub-divided into an SM zone 20 and a non-SM zone 22. The wireless communications network includes multiple MBMS zones. For each MBMS zone, the base stations 24 serving the MBMS zone transmit an MBMS zone identifier (ID) for the MBMS zone.
Abstract:
PROBLEM TO BE SOLVED: To provide systems and methods for providing distributed Automatic Repeat Request (ARQ) in a wireless communication system.SOLUTION: In one embodiment, a relay station interconnects a base station of the wireless communication system and one or more mobile stations. A first ARQ process is performed for a first connection between the base station and the relay station. Separate second ARQ processes are performed for second connections between the relay station and the mobile stations. In this manner, rather than having end-to-end ARQ between the base station and the mobile stations, distributed ARQ is provided.
Abstract:
PROBLEM TO BE SOLVED: To provide a method and an apparatus for performing acquisition, synchronization, and cell selection within an MIMO-OFDM communication system.SOLUTION: A coarse synchronization is performed to determine a searching window. A fine synchronization is then performed for measuring correlations between subsets of signal samples, whose first signal sample lies within the searching window and is known values. The correlations are performed in the frequency domain of the received signal. In a multiple-output OFDM system, each antenna of the OFDM transmitter has a unique known value. The known value is transmitted as pairs of consecutive pilot symbols, each pair of pilot symbols being transmitted at the same subset of sub-carrier frequencies within the OFDM frame.
Abstract:
PROBLEM TO BE SOLVED: To control increase in the peak-to-average power ratio (PAPR) from transmission diversity in a single carrier frequency division multiple access (SC-FDMA) modulated uplink.SOLUTION: An N-point discrete Fourier transform (DFT) with an N-point DFT 300 produces a frequency domain representation Xk of input symbols; a subcarrier mapper 302 maps each of the DFT outputs to one of M (M>N) orthogonal subcarriers that can be transmitted; and an M-point inverse DFT (IDFT) 304 transforms the subcarrier amplitudes to a complex time domain signal. A CDD block 305 passes a reference version 307 of the complex time domain signal to a CP adder 306 for a first transmit antenna 310, and also produces a cyclic shift delayed version 309 of the complex time domain signal to be passed to the CP adder 306 for the second transmit antenna 312.
Abstract:
PROBLEM TO BE SOLVED: To provide wireless communication systems which perform MIMO based network coding.SOLUTION: A first node transmits first data to an intermediate node, and a second node transmits second data to the intermediate node. Both the first node and the second node use one or more of spatial multiplexing, time division multiplexing and frequency division multiplexing on a common/different resource. The intermediate node receives the transmission signals from the first node and the second node, and performs network coding on the first data and the second data using a predefined network coding scheme, to produce network coded information. Then, the intermediate node transmits the network coded information to the first node and the second node using multi-user MIMO. Each of the first and second nodes receives the MIMO transmission signals from the intermediate node, and applies network decoding procedures to recover the first data and the second data.
Abstract:
A wireless terminal and network terminal are provided for implementing a new uplink OFDM protocol. In the new protocol, the wireless terminal has a first transmit chain for generating and transmitting a low rate mode OFDM transmission in a first frequency band of the OFDM band; and a second transmit chain for generating and transmitting a burst-mode transmission in a second frequency band of the OFDM band, the first frequency band being distinct from the second frequency band. An access channel is provided which is overlaid over the low rate mode transmissions of other users.
Abstract:
A system and method for transmitting high speed data on fixed rate and for variable rate channels. The system and method provides the flexibility of adjusting the data rate, the coding rate, and the nature of individual retransmissions. Further, the system and method supports partial soft combining of retransmitted data with previously transmitted data, supports parity bit selection for successive retransmissions, and supports various combinations of data rate variations, coding rate variations, and partial data transmissions.