Abstract: Protocols for OFDM/OFDMA/SC-FDMA based wireless networks provide adaptive inter-cell interference management without explicit spectrum or frequency planning. Base stations and mobile stations acquire information about subcarrier allocation from a handoff protocol. The mobile stations can also acquire this information using cognitive sensing. Cognitive sensing can be rewarded by the base station. Using this information, subcarriers can be allocated randomly, with blind optimization, or by joint optimization. The stations can use game theory to select among the different optimization strategies.

Abstract: A network includes a master node (master) and a set of slave nodes (slaves). The network uses orthogonal frequency-division multiplexing (OFDM) and time division multiple access (TDMA) symbols on sub-carriers. During a first downlink transmission from the master to the set of slaves using downlinks and all of the sub-carriers, a broadcast polling packet including data packets for each slave and sub-carrier assignments for the slaves is broadcast. Each slave transmits simultaneously to the master using uplinks and the assigned sub-carriers, a first response packet after receiving the broadcast polling packet. The master then broadcasts using the downlinks and all of the sub-carriers, a group acknowledgement packet, wherein the broadcast polling packet, the response packet, and the group acknowledgement packet include one superframe in one communication cycle, and wherein the broadcasting on the downlinks and the transmitting on the uplinks are disjoint in time.

Abstract: A frame timing synchronization technique for orthogonal frequency division multiplexing (OFDM) systems is presented. First, a coarse synchronization technique generates a coarse frame timing estimate. The coarse synchronization technique applies a sliding window differentiator to the output of a conventional auto-correlator to mitigate the plateau effect associated with conventional auto-correlation techniques. Second, a fine synchronization technique generates a fine frame timing estimate. The fine synchronization technique uses the coarse frame timing estimate to reduce the number of cross-correlation calculations. Additionally, the fine synchronization technique acquires a fine frame timing estimate based on a signal-to-interference ratio (SIR) metric, which is more robust to multi-paths and pseudo multi-paths caused by cyclic delay diversity (CDD) schemes than conventional cross-correlation synchronization techniques.

Abstract: A method allocates bandwidth to channels in an orthogonal frequency division multiple access and time division multiple access (TDMA) network. The network includes a master device (master) communicating with a set of slave devices (slaves). The master defines a set ?m of logical indices ? of a set of N physical subcarriers for a set of M data streams to be allocated to a set of Nd logical data subcarriers according to ?m={?|?=iM+m, i=0,1,2, . . . , d?1}, where d=Nd/M. The set of N data subcarriers is mapped to the set of Nd logical subcarriers according to the logical indices, and the data subcarriers are allocated to the logical subcarriers.

Abstract: Beams are used to communicate in a wireless network including mobile and stationary receivers. The network operates according to the IEEE 802.11p in wireless access to vehicular environments (WAVE). A direction from the mobile transceiver to the stationary receiver is predicted using geographic information available to the mobile transceiver. A set of signals are received in the mobile transceiver from the stationary transceiver, wherein the signals are received by an array of antennas, and wherein the signals are received using a set of beams, and wherein each beam is approximately directed at the stationary receiver. A signal-to-noise ratio (SNR) is measured for each beam, and the beam with an optimal SNR is selected as an optimal beam for communicating data between the mobile transceiver and the stationary transceiver.

Abstract: An exemplary method is disclosed to accurately estimate the center frequency of a narrow-band interference (NBI). The exemplary method uses multi-stage autocorrelation-function (ACF) to estimate an NBI frequency. The exemplary method allows an accurate estimation of the center frequency of NBI in an Ultra-Wideband system. A narrow band interference (NBI) estimator based on such a method allows a low complexity hardware implementation. The exemplary method estimates the frequency in multiple stages. Each stage performs an ACF operation on the received signals. The first stage gives an initial estimation and the following stages refine the estimation. The results of all stages are combined to produce the final estimation. An apparatus based on such a multi-stage narrow band interference frequency detector is also disclosed to improve the accuracy by combining various filters with the detector.

Abstract: An encoder in a transmitter uses space-time trellis coding. An input bitstream is multiplexed to produce in parallel a set of output bitstreams. A multiplier applies a code generating weight to each output bitstream, which are combined, mapped and transmitted by a single antenna.

Abstract: Embodiments of the invention describe a method for antenna selection (AS) in a wireless communication network. The network includes a base station and a transceiver, wherein the transceiver has a set of antennas, and wherein the transceiver is configured to transmit a frequency-hopped sounding reference signal (SRS) from a subset of antennas at a time. The base station determines a type of a training transmission based on a number of the subbands and a number of subsets in the set of antennas, and transmits an instruction including the type to the transceiver.

Abstract: Source nodes in an International Mobile Telecommunications (IMT)-advanced 4G network transmit data on uplink channels to a relay node and a BS using a channel code. The relay node decodes independently the data received from each source node, and applies network coding to data correctly decoded, and transmits the encoded data to the BS. The BS decodes the encoded data transmitted by the sources nodes and the relay nodes cooperatively via a turbo decoding process. The data from each source node are decoded by soft-input soft-output single user decoders and are decoded, together with the data from the relay node, by a soft-input soft-output multi-user decoder.

Abstract: A method localizes a set of nodes in a wireless network that includes a target node having unknown location and a set of anchor nodes having known locations. The set of anchor nodes is partitioned into subsets of anchor nodes, wherein each subset has at least three anchor nodes. A distance from the target node to each of anchor nodes in each subset is measured, to estimate possible locations of the target node. A geometric constraint is applied to each estimated location to determine valid locations, which are then filtered to determine filtered locations. The filtered locations are averaged to determine an initial estimate of the location.

Abstract: A transmitter encodes an input bitstream using space-time trellis coding (STTC). The encoder includes a serial to parallel convertor to produce a first and second output bitstreams. First and second three bit shift registers are connected to produce first and second output bitstreams. A multiplier applies a code generating weight to each bit of the shift registers to encode the bitstreams. A first switch is connected between a last bit of the first shift register and a first bit of the second shift register. A second switch is connected between the second output and the first bit of the second shift register. The first set of encoded bit streams and the second set of encoded bitstreams are combined and mapped to a frequency domain.

Abstract: A method predicts resource allocations in a wireless network including a set of base stations (BSs). Each BS is in a cell, and serves a set of mobile stations. A sequence and rule of resource allocations are defined for all of the BSs. Previous resource allocations are acquired from the BSs in adjacent cells. In each BS, for a next allocation, inter-cell interference (ICI) is predicted independently for the set of MSs in the cell based on the previous resource allocations by the BSs in the adjacent cells and the sequence and rule of resource allocations. Then, each BS allocates the resources to the MSs in the cell based on the ICI and the previous resource allocations.

Abstract: A method, MIMO communication device and electronic storage medium for mapping symbols during a duration of each plural consecutive frames of each of a plurality of first data streams (10, 12, 14, 16, 18, 20, 22, 24, 26) to frames of a plurality of second data streams (spaced-time coded streams or antenna streams); and varying the mapping during the duration of each of the plural consecutive frames of each of the plurality of first data streams (10, 12, 14, 16, 18, 20, 22, 24, 26).

Abstract: A method schedules voice communication in an Orthogonal Frequency Division Multiplexing Access (OFDMA) network of base stations serving sets of mobile stations in cells. The method uses statistical characteristics of voice communications by adjusting scheduling periods accordingly to measurement reports provided by the mobile stations. The base stations generally use persistent scheduling for voice transmission due to inherent characteristics, along with extra signaling concerns. Base stations have the liberty of shortening or prolonging the scheduling period according to their needs while taking into account changes in dynamic conditions. This method makes use of the measurement reports provided by the mobile stations along with a shortened scheduling period in order to reduce ICI.

Abstract: A method allocates resource in an Orthogonal Frequency-Division Multiple Access (OFDMA) network, including a set of Base Stations (BSs) and a set of Mobile Stations (MSs) for each BS. OFDMA frame are constructed as multiple resource blocks, and each resource block contains symbols transmitted on different subcarriers. A cluster is formed from adjacent sectors of different neighboring cells to jointly optimize the resource allocation in multiple frames, and three non-overlap zones are sequentially identified in cluster: cell center zone, cell edge zone, and cluster corner zone. Resource allocation includes intra-cluster proportional fair scheduling and inter-cluster interference mitigation. Intra-cluster scheduling further includes resource allocation for cell center zone and resource allocation for cell edge zone.

Abstract: A method performs handover of a mobile station (MS from a current base station (BSC) connected to a target base station (BST) via a backbone in a Worldwide interoperability for Microwave Access (WiMAX) mobile communication network. The MS, before handover, transmits a Connection Identifier Request (CID-REQ) to the BST via the BSC, and receiving a Connection Identifier Response (CID-RSP) from the BST via the BSC. The MS, before handover, transmits a Subscriber Station (SS) Basic Capability Request (SBC-REQ), and receives a SS Basic Capability Response (SBC-RSP) from the BST via the BSC. Then, the MS transmits a Ranging Request (RNG-REQ) to the BST, and receives a Ranging Response (RNG-RSP) from the BST. During the handover, the MS transmits a Registration Request (REG-REQ) to the BST, and receives a Registration Response from the BST to establish the connection between the MS and the BST.

Abstract: A method measures a time from transmitting a ranging signal to receiving the ranging signal via a channel of a wireless network, and a received signal strength (RSS) of the ranging signal. A distance is estimated based on the time, and a path loss based on the RSS. Probabilities of conditions of the channel are estimated based on the distance and the path loss, wherein the condition is in one of line-of-sight (LOS), or non-LOS (NLOS).

Abstract: A method for allocating resources in an orthogonal frequency division multiple access (OFDMA) network, where each cell in the network has a center region and an edge region. The cell center region uses a frequency band orthogonal to the frequency band used by the cell edge region. The frequency band is made up of resource blocks (RBs) or non-overlapping sets of subcarriers. Upon availability of cell-center RBs, cell-center user equipment (UEs) are assigned resource blocks. A fixed number of cell edge regions from a few adjacent cells form a cluster, and only the cell edge regions with the highest achievable throughput rate within each cluster gets to transmit in a given scheduling instance.

Abstract: Channel state information for closed-loop transmit precoding in MIMO networks is fed back from the MSs to the BSs. The feedback is quantized using codebooks shared by the MSs and BSs to reduce overhead. The codebooks can be full-rank or rank-one. The quantized feedback is applicable to any definitions of MIMO channel covariance matrix as well as MIMO channel matrix. Since these codebooks are designed for closed-loop MIMO precoded transmissions, no additional memory is needed to store the codebooks at the BS and the MS only for the quantized feedback purposes.

Abstract: A method and system provide multiple-access control and frequency band allocation, and transmission time sharing among multiple users in orthogonal frequency-division multiple-access (OFDMA) and time-division multiple-access (TDMA) networks. The method can be applied to uplinks and downlinks of multi-user, multi-carrier communication networks. Under a total transmission-power minimization constraint, the method can allocate carriers and transmission time to users optimally, and at the same time, can guarantee a data rate or equivalently a latency requirement of each user.