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 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:
Systems and methods for OFDM channelization are provided that allow for the coexistence of sub-band channels and diversity channels. Methods of defining diversity sub-channels and sub-band sub-channels are provided, and systematic channel definition and labeling schemes are provided.
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:
In a method of transmitting a data stream from a transmitter in a multiple-input-multiple-output (MIMO) wireless communication system, where the transmitter comprises a plurality of transmit antennas, a discrete Fourier transform (DFT) is applied to the data stream to generate a plurality of symbol sequences; symbols of a first symbol sequence from the plurality of symbol sequences are paired with symbols of a second symbol sequence from the plurality of symbol sequences to generate a plurality of symbol pairs, wherein the pairing results in an orphan symbol; a space-time block code (STBC) is applied to the symbol pairs to generate a plurality of sets of STBC symbols, each set of STBC symbols being associated with a corresponding one of the plurality of antennas; a cyclic delay diversity (CDD) operation is applied to the orphan symbol to generate a plurality of CDD symbols, each CDD symbol being associated with a corresponding one of the plurality of antennas; and each one of the antennas transmits the corresponding set of STBC symbols and the corresponding CDD symbol.
Abstract:
In some embodiments of the present invention there is provided a frame structure for transmitting an integer number of OFDM symbols in which some of the OFDM symbols are to be transmitted in a unicast format and some of the OFDM symbols are to be transmitted in a broadcast format. The frame structure includes partitioning of a frame into at least two portions to accommodate both unicast and broadcast modes in the frame. The frame structure is used for transmitting multiple frames in a serial manner from at least one transmitter. The unicast mode supports transmission of OFDM symbols from a single transmitter to a single receiver. The broadcast mode supports transmission of OFDM symbols from multiple transmitters to all receivers within range of the multiple transmitters. The multicast mode supports transmission of OFDM symbols from multiple transmitters to multiple receivers within range of the multiple transmitters.