Abstract: Spatial multiplexing and transmit diversity can improve the capacity of a wireless communication system. The system and method adapts communication schemes for communication systems with multiple antennas utilizing at least two transmission modes. The at least two transmission modes can, but are not necessarily, used for uplink communications. The two transmission modes may be chosen from the group consisting of a single antenna mode, a diversity mode a spatial multiplexed mode and a mixed diversity and spatial multiplexed mode. The at least two transmission modes may involve adaptation among multiple transmitters. At least one receiver may indicate a transmission mode to be used by a transmitter for a subsequent transmission. A transmitter may determine a transmission mode to be used for a subsequent transmission. The transmission mode can be based on channel sounding.

Abstract: A unified frame structure for filter bank multi-carrier (FBMC) and orthogonal frequency division multiplexed (OFDM) waveforms may allow FBMC and OFDM frames to be communicated over a common channel without significant inter-frame gaps. The unified frame structure may set an FBMC frame duration to an integer multiple of an OFDM frame element duration to enable alignment of FBMC frames and OFDM frames in the time domain. The unified frame structure may also map control channels in the FBMC and OFDM frames to common resource locations so that the respective control channels are aligned in the time and/or frequency domains. The unified frame structure may also share synchronization channels between FBMC and OFDM frames. Additionally, overhead in an FBMC time division duplexed (TDD) communications channel can be reduced by overlapping time windows appended to FBMC blocks.

Abstract: Aspects of the invention include methods and devices for inserting data and pilot symbols into Orthogonal Frequency Division Multiplexing (OFDM) frames having a time domain and a frequency domain. A method involves inserting in at least one zone of a first type a two dimensional array of data and pilot symbols in time and frequency and inserting in at least one zone of a second type a two dimensional array of data and pilot symbols in time and frequency. In some implementations the zone of the first type comprises common pilot symbols that can be detected by all receivers receiving the OFDM frame. In some implementations the zone of the second type comprises dedicated pilot symbols that are only detectable by a receiver that is aware of pre-processing used to encode the dedicated pilot symbols.

Abstract: A method and apparatus are provided for reducing the number of pilot symbols within a MIMO-OFDM communication system, and for improving channel estimation within such a system. For each transmitting antenna in an OFDM transmitter, pilot symbols are encoded so as to be unique to the transmitting antenna. The encoded pilot symbols are then inserted into an OFDM frame to form a diamond lattice, the diamond lattices for the different transmitting antennae using the same frequencies but being offset from each other by a single symbol in the time domain. At the OFDM receiver, a channel response is estimated for a symbol central to each diamond of the diamond lattice using a two-dimensional interpolation. The estimated channel responses are smoothed in the frequency domain. The channel responses of remaining symbols are then estimated by interpolation in the frequency domain.

Abstract: Methods and systems are provided that enable an OFDM transmitter to be used for transmitting conventional OFDM or a form of transformed OFDM. A technique is provided for transforming a coded and modulated sequence of samples prior to an IFFT that enables the transformed sequence of samples to be transmitted using conventional OFDM or transformed OFDM. The selection of a transform function for transforming the coded and modulated sequence of samples may be based on optimizing the transform function for particular operating conditions between the transmitter and receiver. In some embodiments of the invention OFDM and time transformed OFDM are multiplexed in time and/or frequency in a transmission frame. In some embodiments of the invention a pilot pattern is provided in which the pilot are sent using OFDM and data is sent using OFDM and/or transformed OFDM.

Abstract: A method includes generating, by a transmitter, an original OFDM signal having at least one OFDM symbol, the at least one OFDM symbol having an associated time domain tail; truncating, by the transmitter, at least a portion of the time domain tail to produce a truncated OFDM signal; and transmitting, by the transmitter, the truncated OFDM signal.

Abstract: An OFDM signal may include a first edge band signal corresponding to a first edge band of the bandwidth of the OFDM signal, a second edge band signal corresponding to a second edge band of the bandwidth, and a center band signal corresponding to a center band of the bandwidth. The OFDM signal may be filtered by filtering the first edge band signal and/or the second edge band signal, so that out-of-band radiation of the OFDM may be reduced or eliminated.

Abstract: A codebook C is provided in a MIMO transmitter as well as a MIMO receiver. The codebook C will include M codewords ci, where i is a unique codeword index for each codeword ci. Each codeword defines weighting factors to apply to the MIMO signals, and may correspond to channel matrices or vectors to apply to the MIMO signals prior to transmission from the respective antennas of the MIMO transmitter. The present invention creates codeword subsets Si for each codeword ci of the codebook C. Each codeword subset Si defines L codewords cj, which are selected from all the codewords ci in the codebook C. The codewords cj in a codeword subset Si are the L codewords in the entire codebook that best correlate with the corresponding codeword ci.

Abstract: Pilot, preamble and midamble patterns are provided that are particularly suited for four transmit antenna OFDM systems. Pilots are inserted in a scattered manner for each of the four antennas, either uncoded, space-time coded in pairs, space-time frequency coded in pairs, or space-time-frequency coded.

Abstract: Systems and methods are disclosed herein for an enhanced Multimedia Broadcast Multicast Service (MBMS) in a wireless communications network. In one embodiment, a number of base stations in a MBMS zone, or broadcast region, accommodate both Spatial Multiplexing (SM) enabled user elements and non-SM enabled user elements. In another embodiment, a number of base stations form a MBMS zone, or broadcast region, where the MBMS zone is sub-divided into an SM zone and a non-SM zone. In another embodiment, the wireless communications network includes multiple MBMS zones. For each MBMS zone, base stations serving the MBMS zone transmit an MBMS zone identifier (ID) for the MBMS zone. The MBMS zone ID may be used by a user element for decoding and/or to determine when to perform a handoff from one MBMS zone to another.

Abstract: A transmitter adapted for massive multiple-input multiple-output (M-MIMO) operation includes a first set of power amplifiers (PAs) that amplifies a first signal to produce an amplified first signal, and a second set of PAs that amplifies a second signal to produce an amplified second signal, wherein PAs in the first set of PAs are different from PAs in the second set of PAs. The transmitter includes an antenna array operatively coupled to the first set of PAs and the set of second PAs, the antenna array including a plurality of transmit antennas, wherein the antenna array transmits one or more of the amplified signals.

Abstract: Physical layer structures and access schemes for use in such networks are described and in particular initial access channel (IACH) structures are proposed. A spectrum efficient downlink (DL) IACH design supports different types of User Equipment (UE) capabilities and different system bandwidths. An IACH includes the synchronization channel (SCH) and broadcast-control channel (BCH). A non-uniform SCH for all system bandwidths is provided, as well as scalable bandwidth BCH depending on system bandwidth. An initial access procedure is provided, as well as an access procedure.

Abstract: Methods and systems are provided for use with wireless networks having one or more cell in which each cell includes a base station (BS), at least one relay station (RS) and at least one mobile station (MS). The at least one relay station can be used as an intermediate station for providing communication between the BS and MS. Methods are provided for an RS to initially access the network, access of the RS by MSs initially accessing the network, methods of allocating OFDM resources for communicating between the BS, RS and/or MS for example dividing transmission resources into uplink and downlink transmissions, and methods of inserting pilot symbols into transmission resources used by the RS. In some embodiments on the invention, the methods are consistent and/or can be used in conjunction with existing standards such as 802.16e.

Abstract: A method for operating a transmitting device using semi-orthogonal multiple access (SOMA) includes determining power allocations and sub-quadrature amplitude modulation (sub-QAM) allocations for a first receiving device and a second receiving device in accordance with channel information associated with the first receiving device and the second receiving device, and transmitting information about a first power allocation for the first receiving device, and a first sub-QAM allocation for the first receiving device to the first receiving device.

Abstract: A method and apparatus are provided for performing acquisition, synchronization and cell selection within an MIMO-OFDM communication system. A coarse synchronization is performed to determine a searching window. A fine synchronization is then performed by measuring correlations between subsets of signal samples, whose first signal sample lies within the searching window, and 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: The present invention provides a solution to improve coverage and cell edge performance in a mobile user communication system is the use of fixed relays, which are pieces of infrastructure without a wired backhaul connection. The relays transmit or “relay” downlink messages between the base station (BS) and mobile stations (MSs) through a multi-hop communication. The present invention is a method and system for supporting a multiple user mobile broadband communication network that includes relay techniques suitable for user equipment in the downlink communication to the user equipment.

Abstract: System and method embodiments are provided for a receiver for circularly convolved signals. In an embodiment, a universal decoder for a circularly convolved signal includes a first decoder configured to decode the circularly convolved signal; a second decoder configured to decode a plurality of symbol lengths signal from a first portion of the circularly convolved signal, wherein the plurality of symbol lengths signal is time aligned with the circularly convolved signal before passing through the second decoder; and an adder component configured to sum a first decoder output coming from the first decoder and a second decoder output coming from the second decoder to produce a symbol value from which a log likelihood ratio (LLR) output is obtained.

Abstract: The present invention employs a pilot scheme for frequency division multiple access (FDM) communication systems, such as single carrier FDM communication systems. A given transmit time interval will include numerous traffic symbols and two or more short pilot symbols, which are spaced apart from one another by at least one traffic symbol and will have a Fourier transform length that is less than the Fourier transform length of any given traffic symbol. Multiple transmitters will generate pilot information and modulate the pilot information onto sub-carriers of the short pilot symbols in an orthogonal manner. Each transmitter may use different sub-carriers within the time and frequency domain, which is encompassed by the short pilot symbols within the transmit time interval. Alternatively, each transmitter may uniquely encode the pilot information using a unique code division multiplexed code and modulate the encoded pilot information onto common sub-carriers of the short pilot symbols.

Abstract: Aspects of the invention include methods and devices for inserting data and pilot symbols into Orthogonal Frequency Division Multiplexing (OFDM) frames having a time domain and a frequency domain. A method involves inserting in at least one zone of a first type a two dimensional array of data and pilot symbols in time and frequency and inserting in at least one zone of a second type a two dimensional array of data and pilot symbols in time and frequency. In some implementations the zone of the first type comprises common pilot symbols that can be detected by all receivers receiving the OFDM frame. In some implementations the zone of the second type comprises dedicated pilot symbols that are only detectable by a receiver that is aware of pre-processing used to encode the dedicated pilot symbols.

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.