Abstract: A system and method for synchronous spectrum sharing for use in a wireless communication system based on orthogonal frequency-division multiplexing (OFDM) or orthogonal frequency division multiple access (OFDMA) signaling is disclosed. The system includes a frame detector configured to detect a frame of a broadcast waveform and extract sub-carrier information from the frame. Sub-carrier information may include information on usable sub-carrier and pilot sub-carriers for secondary users. The system allows transmitting data from the secondary user node in unused sub-carriers thereby making efficient use of unused or idle spectrum. Accordingly, secondary users of wireless communication systems can dynamically form ad-hoc mesh network communications in fixed or mobile scenarios.

Abstract: A receiver for receiving a signal including a series of symbols, the signal being performed Time Window processing at portions including a boundary of adjacent symbols by a transmitter so as to eliminate a discontinuity between the symbols, the receiver includes: a receiving unit that receives the signal; and a processor extracts the series of symbols and performing an inverse processing of the Time Window processing at the portions performed the Time Window processing by the transmitter.

Abstract: A signal receiving unit receives the OFDM signal and to convert the OFDM signal into a baseband OFDM signal. A time wave operation unit performs a predetermined calculation on a time wave signal that is an output of the signal receiving unit. A Fourier transform unit performs a Fourier transform on an output of the time wave operation unit. A frequency component extraction unit extracts a specific frequency component from an output of the Fourier transform unit. An inverse Fourier transform unit performs an inverse Fourier transform on the frequency component extracted by the frequency component extraction unit. A reception quality measurement unit measures quality of an output signal of the inverse Fourier transform unit and generate reception quality data. A time wave control unit controls the time wave operation unit based on the reception quality data.

Abstract: Data errors are sufficiently corrected and desired transmission quality is obtained even when the time variation of fading is large in a multicarrier transmission scheme communication system to which HARQ is applied. A transmission apparatus 100 is applied to a communication system in which the transmission apparatus and a reception apparatus perform automatic repeat request control therebetween, and has a subcarrier spacing setting section 111 that sets the subcarrier spacing used in transmitting a retransmission signal to be larger than the subcarrier spacing used in transmitting a first transmission signal, an IFFT section 112 that performs IFFT (Inverse Fast Fourier Transform) on an input signal based on the subcarrier spacing set in the subcarrier spacing setting section 111, and a transmission section 102 that transmits the first transmission signal and at least one retransmission signal.

Abstract: A connection state estimating method includes: acquiring a network distance between respective devices in a communication network; assuming branch point candidates at which three devices extracted from the network are connected together; calculating the network distance between each of the assumed branch point candidates and each of the three devices; classifying all the branch point candidates assumed to be connected with one of the devices into groups on the basis of the network distance between the one device and each branch point candidate; calculating representative values of the network distances between each device and branch point candidates assumed to be connected with the device; and selecting a device from the devices assumed to be connected with one of the branch point candidates and the representative value relating to the selected device.

Abstract: Sounding reference signal presence information is incorporated into an uplink data resource assignment for a user equipment, and the uplink data assignment including the sounding reference signal presence information is sent to the user equipment.

Abstract: A communications system having an ATM transmission line and an IP transmission line is disclosed that includes a base station capable of communicating with a mobile terminal through a radio link; and a radio network controller capable of communicating with the base station through the ATM or IP transmission line. The radio network controller includes a division part dividing transmission data into signals of a predetermined data size; a transmission part transmitting the divided signals to the base station at predetermined time intervals; a retransmission part retransmitting the signals transmitted to the base station when a response signal from the mobile terminal is not received within a predetermined period; a measuring part measuring a signal response period in a communications channel between the radio network controller and the mobile terminal through the base station; and a determination part determining the predetermined data size based on the measured response period.

Abstract: Provided is a radio communication device which can suppress inter-code interference between an ACK/NACK signal and a CQI signal which are code-multiplexed. A diffusion unit (214) diffuses the ACK/NACK signal inputted from a judgment unit (208) by using a ZC sequence. A diffusion unit (219) diffuses the CQI signal by using a cyclic shift ZC sequence. By using a Walsh sequence, a diffusion unit (216) further diffuses the ACK/NACK signal which has been diffused by using the ZC sequence. A control unit (209) controls the diffusion unit (214), the diffusion unit (216), and the diffusion unit (219) so that the minimum value of the difference between the CQI signals from a plurality of mobile stations and a cyclic shift amount of the ACK/NACK signal is not smaller than the minimum value of the difference between the cyclic shift amounts of the ACK/NACK signals from the plurality of mobile stations.

Abstract: A transmitting apparatus for transmitting signals in a multi carrier system on the basis of a frame structure, each frame comprising at least two preamble patterns adjacent to each other in the frequency direction and at least two data patterns, said transmitting apparatus comprising a pilot mapper configured to map the same sequence of pilot signals on frequency carriers of each of said at least two preamble patterns in a frame, each preamble pattern having the same length, a data mapper configured to map data on frequency carriers of said at least two data patterns in a frame, a transformer configured to transform said preamble patterns and said data patterns from the frequency domain into the time domain in order to generate a time domain transmission signal, and a transmitter configured to transmit said transmission signal.

Abstract: Allocation of subcarriers of a wireless communications channel to antennas for transmission of said subcarriers from a multi-antenna transmitter, comprises selecting, for each subcarrier, the antenna with the most effective transmission performance against a predetermined performance criterion; and determining if subcarriers are evenly distributed amongst said antennas. If even distribution does not arise, then a reallocation sequence is performed. This comprises identifying, for an antenna having excessive subcarriers allocated thereto, the subcarriers allocated thereto and reallocating one of said subcarriers as required, said reallocated subcarrier being selected for reallocation on the basis of its impact on transmission performance.

Abstract: A resource allocation method and apparatus of a multi-relay orthogonal frequency division multiplexing system are disclosed. The resource allocation method of a multi-relay orthogonal frequency division multiplexing system includes: obtaining actual channel information; obtaining resource allocation parameters according to a mathematical optimization problem based on the actual channel information, where the resource allocation parameters include at least two of subcarrier power allocation, relay selection and subcarrier pairing, and the mathematical optimization problem is a mathematical optimization problem set for the subcarrier power allocation, relay selection and subcarrier pairing by using an end-to-end transmission rate optimization principle and based on channel information; and transmitting a signal according to the resource allocation parameters. The foregoing technical solutions optimize system performance.

Abstract: A quantized multi-rank beamforming scheme for multiple-antenna systems such as a multiple-input-multiple-output (MIMO) wireless downlink User equipment (UE) estimates downlink channel and transmit power and determines rank and power allocations. A quantized beamforming matrix is then determined by the UE using successive beamforming. The UE also determines channel quality indices (CQI) which it feeds-back to the wireless downlink base station along with the index of the quantized beamforming matrix. The base station uses the CQI information to select a UE for scheduling of downlink transmission and the quantized beamforming matrix index received from the selected UE to beamform the downlink transmission to the UE. Base station overhead and is minimized while providing near-optimal performance given the constraints of a limited feed-back channel and computational complexity of the UE.

Abstract: A method and apparatus for radio resources control in a multiple input multiple output (MIMO) orthogonal frequency division multiplexing (OFDM) communication system are disclosed. Channel metric is calculated for each of a plurality of transmit antennas. Sub-carriers are allocated to each transmit antenna in accordance with the channel metric of each transmit antenna. Signals are transmitted using the allocated sub-carriers at each antenna. Adaptive modulation and coding and transmit power control of each sub-carrier may be further implemented in accordance with the channel metric. Power control may be implemented per antenna basis or per sub-carrier basis. In performing power control, a subset of transmit antennas may be selected and waterpouring may be applied only to the selected antennas. Waterpouring may be based on SNR instead of channel response.

Abstract: In a wireless communication system, a portable device and an in-vehicle device wirelessly communicate with each other by a spread spectrum method. The in-vehicle device transmits a synchronization signal indicative of a reference period to the portable device. The in-vehicle device performs code acquisition for only a portion of a spread wireless signal received from the portable device. The portion has a starting point in a search period from a search start point to a search end point. The search start point is identified based on the reference period and a predetermined first correction time. The search end point is identified based on the reference period and a predetermined second correction time.

Abstract: A quantized multi-rank beamforming scheme for multiple-antenna systems such as a multiple-input-multiple-output (MIMO) wireless downlink User equipment (UE) estimates downlink channel and transmit power and determines rank and power allocations. A quantized beamforming matrix is then determined by the UE using successive beamforming. The UE also determines channel quality indices (CQI) which it feeds-back to the wireless downlink base station along with the index of the quantized beamforming matrix. The base station uses the CQI information to select a UE for scheduling of downlink transmission and the quantized beamforming matrix index received from the selected UE to beamform the downlink transmission to the UE. Base station overhead and is minimized while providing near-optimal performance given the constraints of a limited feed-back channel and computational complexity of the UE.

Abstract: A signal mapping method and a signal transmission method applying a subcarrier shift method are described. A signal mapping method using shifted subcarriers includes shifting positions of data subcarriers by as much as a frequency band corresponding to half of spacing between data subcarriers on a frequency axis, and shifting positions of random access preamble subcarriers by as much as a frequency band corresponding to half of spacing between the data subcarriers and to a specific ratio of spacing between the random access preamble subcarriers, and mapping data and a random access preamble to the data subcarriers and the random access preamble subcarrier, respectively. Even when the spacing between the data subcarriers is a multiple of the spacing between the random access preamble subcarriers, DC distortion can be minimized.

Abstract: A quantized multi-rank beamforming scheme for multiple-antenna systems such as a multiple-input-multiple-output (MIMO) wireless downlink. User equipment (UE) estimates downlink channel and transmit power and determines rank and power allocations. A quantized beamforming matrix is then determined by the UE using successive beamforming. The UE also determines channel quality indices (CQI) which it feeds-back to the wireless downlink base station along with the index of the quantized beamforming matrix. The base station uses the CQI information to select a UE for scheduling of downlink transmission and the quantized beamforming matrix index received from the selected UE to beamform the downlink transmission to the UE. Base station overhead and is minimized while providing near-optimal performance given the constraints of a limited feed-back channel and computational complexity of the UE.

Abstract: A quantized multi-rank beamforming scheme for multiple-antenna systems such as a multiple-input-multiple-output (MIMO) wireless downlink. User equipment (UE) estimates downlink channel and transmit power and determines rank and power allocations. A quantized beamforming matrix is then determined by the UE using successive beamforming. The UE also determines channel quality indices (CQI) which it feeds-back to the wireless downlink base station along with the index of the quantized beamforming matrix. The base station uses the CQI information to select a UE for scheduling of downlink transmission and the quantized beamforming matrix index received from the selected UE to beamform the downlink transmission to the UE. Base station overhead and is minimized while providing near-optimal performance given the constraints of a limited feed-back channel and computational complexity of the UE.

Abstract: Methods and systems for indexing subband selections are disclosed. The selected subbands can be represented as a binary sequence and the index can be determined by employing a choose function, where a choose function value for a particular selected bit position is defined by a selection occurrence count of the selected bit position that is chosen from a bit position count of the selected bit position. In particular, the index can be the summation of choose function values for each selected bit position.

Abstract: A method and apparatus for transmitting and receiving data in an Orthogonal Frequency Division Multiplexing (OFDM) system are provided, in which a Base Station (BS) generates a signal of a broadcast channel, determines whether the broadcast channel signal includes Reference Symbols (RSs) used for channel estimation, determines to apply a maximal puncturing pattern to a Resource Block that defines the broadcast channel, if the broadcast channel signal includes Rs, includes puncturing information about a downlink signal in the broadcast channel signal, maps the broadcast channel signal including the puncturing information to Resource Elements according to the maximal puncturing pattern, and transmits the mapped broadcast channel signal.

Abstract: A quantized multi-rank beamforming scheme for multiple-antenna systems such as a multiple-input-multiple-output (MIMO) wireless downlink. User equipment (UE) estimates downlink channel and transmit power and determines rank and power allocations. A quantized beamforming matrix is then determined by the UE using successive beamforming. The UE also determines channel quality indices (CQI) which it feeds-back to the wireless downlink base station along with the index of the quantized beamforming matrix. The base station uses the CQI information to select a UE for scheduling of downlink transmission and the quantized beamforming matrix index received from the selected UE to beamform the downlink transmission to the UE. Base station overhead and is minimized while providing near-optimal performance given the constraints of a limited feed-back channel and computational complexity of the UE.

Abstract: A system and method for initial ranging in wireless communication systems is provided. A plurality of orthogonal frequency division multiplexing (OFDM) blocks are received by an OFDMA base station transceiver from a plurality of remote user devices in wireless communication with the base station. A ranging subchannel is extracted from the OFDM blocks. The number of active codes in the ranging subchannel is determined, active codes are identified, and carrier frequency offsets (CFOs) are estimated for each active code. Timing delays and power levels for each active code are then estimated. The estimated CFOs, timing delays, and power levels are broadcasted by the base station to the remote user devices, so that the user devices can utilize same to adjust transmission parameters to optimize power levels and synchronize communication with the base station.

Abstract: A receiver receives a reception signal subjected to orthogonal frequency division multiplexing modulation or orthogonal frequency division multiple access modulation. The receiver has: an array antenna for receiving the reception signal; adaptive equalizers provided in each of the plurality of antennas, and reducing advanced or delayed waves having a delay time to a main wave in the reception signal; a spatial diversity combining portion which multiplies output signals of the adaptive equalizers by a weighting coefficient and adds the multiplied signals; a weight control portion generating the weighting coefficient; and an equalizer setting unit which estimates an arrival angle and a delay time for each path of the reception signal, and based on the estimation, decides an interference wave to be eliminated by the adaptive equalizers among interference waves, and sets in the adaptive equalizers the delay time of the decided interference wave.

Abstract: An exemplary wireless communication network that includes a base that communicates with remote units located in a cell of the network. A base concatenates information symbols with a preamble corresponding to a destination remote unit. One or more remote units communicating with a base each concatenates information symbols with a preamble corresponding to that remote unit. An adaptive receiver system for a base unit rapidly adapts optimal despreading weights for reproducing information symbols transmitted from multiple remote units. A transmitter system for a base unit concatenates information symbols with a preamble associated with a remote unit in the cell. An adaptive receiver system for a remote unit in a communication network rapidly adapts optimal weights for reproducing a signal transmitted to it by a specific base unit in the network. A transmitter system for a remote unit in a cell of a communication network which concatenates information symbols with preamble associated with the remote unit.

Abstract: A method and application for generating an interleaver or a de-interleaver are described. The method for generating interleaver includes: setting interleaving information of a base interleaver and/or de-interleaving information of a base de-interleaver, and respectively performing a cyclic shift transform on the interleaving information of the base interleaver so as to generate a plurality of different interleavers. Alternatively, the method for generating interleaver includes: deducing from the de-interleaving information to obtain the interleaving information of the base interleaver and performing the cyclic shift on the interleaving information obtained by deduction so as to generate a plurality of different interleavers.

Abstract: A method and apparatus for decomposing a channel matrix in a wireless communication system are disclosed. A channel matrix H is generated for channels between transmit antennas and receive antennas. A Hermitian matrix A=HHH or A=HHH is created. A Jacobi process is cyclically performed on the matrix A to obtain Q and DA matrixes such that A=QDAQH. DA is a diagonal matrix obtained by singular value decomposition (SVD) on the A matrix. In each Jacobi transformation, real part diagonalization is performed to annihilate real parts of off-diagonal elements of the matrix and imaginary part diagonalization is performed to annihilate imaginary parts of off-diagonal elements of the matrix after the real part diagonalization. U, V and DH matrixes of H matrix are then calculated from the Q and DA matrices. DH is a diagonal matrix comprising singular values of the H matrix.

Abstract: A quantized multi-rank beamforming scheme for multiple-antenna systems such as a multiple-input-multiple-output (MIMO) wireless downlink User equipment (UE) estimates downlink channel and transmit power and determines rank and power allocations. A quantized beamforming matrix is then determined by the UE using successive beamforming. The UE also determines channel quality indices (CQI) which it feeds-back to the wireless downlink base station along with the index of the quantized beamforming matrix. The base station uses the CQI information to select a UE for scheduling of downlink transmission and the quantized beamforming matrix index received from the selected UE to beamform the downlink transmission to the UE. Base station overhead and is minimized while providing near-optimal performance given the constraints of a limited feed-back channel and computational complexity of the UE.

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 base station that communicates with subscriber stations in an OFDM wireless network. The base station transmits broadcast data and unicast data to the subscriber stations from a plurality of antennas using multiple-input, multiple-output (MIMO) techniques. The base station transmits a first broadcast pilot signal from a first antenna orthogonally to at least one of: i) a first unicast pilot signal transmitted from the first antenna; ii) a second unicast pilot signal transmitted from a second antenna; iii) a second broadcast pilot signal transmitted from the second antenna; and iv) superimposed broadcast data traffic and unicast data traffic transmitted from the first and second antennas. The base station uses orthogonal subcarriers or orthogonal time slots.

Abstract: Embodiments according to the application relates to an OFDM (orthogonal frequency division multiplexing) receiving circuit and methods thereof configured to have a plurality of demodulation paths for an oversampling ADC, which can increase or improve an overall performance of the circuit.

Abstract: Methods of a slot-level remapping physical uplink control channels into two resource blocks respectively located at two slots of a subframe, are generally adapted to a 3GPP LTE physical uplink where ACK/NAK resource blocks may be applied by the extended cyclic prefix, adapted to a complex 3GPP LTE physical uplink where mixed resource blocks (where the ACK/NAK and CQI channels coexist) may be applied by the normal cyclic prefix, and adapted to a complex 3GPP LTE physical uplink where mixed resource blocks (where the ACK/NAK and CQI channels coexist) may be applied by the extended cyclic prefix.

Abstract: An OFDM signal transmission apparatus is provided, which includes a mapping unit configured to map first signals into N subcarriers and second signals into M subcarrier(s) to form an OFDM signal, wherein N is larger than M. The first signals are each indicating a same bit of retransmission information and the second signals are each indicating a same bit of information other than retransmission information. The OFDM signal transmission apparatus further includes a transmitting unit configured to transmit the formed OFDM signal.

Abstract: The present disclosure relates to the management of control information in a multi-user multi-input multi-output system with a base unit and two or more user units, where respective user unit sends an index representing a vector from a user codebook belonging to the user unit. The base unit co-schedules compatible user units to simultaneously share one time-frequency resource by selecting a precoding matrix from a base unit codebook based on the indices received from co-scheduled user units, according to a predefined function. The base unit transmits control information regarding selected precoding matrix to each co-scheduled user unit. The predefined function is known to each user unit and the control information to each user unit only contains information on the index from every other user unit.

Abstract: An error between the rate fsym at which data are received and the rate fs at which the data are sampled in is determined by processing a received signal with a nonlinear operator, performing a DFT on the processed signal to produce a plurality of DFT bins each characterized by a respective frequency, determining a dominant spectral component k0 from at least two of the DFT bins whose frequencies are substantially close to the frequency of the dominant spectral component k0, and determining the data rate fsym from the dominant spectral component k0.

Abstract: An apparatus and method for transmitting/receiving an S-SCH in an Institute of Electrical and Electronics Engineers (IEEE) 802.16m wireless communication system are provided. A method for transmitting, by a transmitter, a Secondary Synchronization CHannel (S-SCH) in a communication system includes generating a sequence depending on a cell IDentification (ID), determining a subcarrier set comprising subcarriers to map the generated sequence, based on a Fast Fourier Transform (FFT) size and a segment ID, and mapping the generated sequence to the subcarriers of the determined subcarrier set.

Abstract: A method for detecting and/or estimating a ranging signal in a wireless communications network, wherein the ranging signal comprises a plurality of tiles. The method includes (i) for two or more of the plurality of tiles, carrying out a plurality of mathematical correlations for one or more of the plurality of tiles but less than all of the plurality of tiles products between subcarriers, wherein at least one of the plurality of products is carried out between non-adjacent subcarriers associated with one of the two or more of the plurality of tiles; (ii) summing the results of the correlations products, thereby obtaining mathematical correlations that make up summed results; and (iii) based on the summed results, detecting a code characterizing the ranging signal and/or estimating the timing offset of the ranging signal.

Abstract: Methods and apparatus for establishing multiple connections between a wireless device and multiple base stations and transferring data using these connections via different segments of an orthogonal frequency division multiple access (OFDMA) frame are provided. The multiple connections may be used for multi-way (e.g., three-way) concurrent processing, multi-way (e.g., three-way) handover, or a hybrid between concurrent processing and multi-way handover in an effort to increase data throughput for the wireless device.

Abstract: A method and apparatus may be used to enable reception of a downlink (DL) shared channel in a cooperative multipoint transmission (CoMP). The method and apparatus may determine whether CoMP is applied to a transmission. The method and apparatus may acquire other CoMP related information. The method and apparatus may apply to non-transparent CoMP scenarios.

Abstract: A delay indicator calculator calculates at least two of a first delay indicator indicating a delay time determined based on a correlation value having a predetermined difference from the maximum value of the correlation signal, a second delay indicator indicating a change of a delay time determined based on time during which the correlation signal has no less than a predetermined value, and a third delay indicator indicating a change of a time difference between main and delay path peaks. An estimator generates a state estimation of the transmission path based on the probabilities of the at least two delay indicator values exceeding respective reference values for a plurality of symbols.

Abstract: A non-cyclic evolving-type user resource structure applicable for use in the uplink and the downlink of an OFDMA system with large null guard tones (e.g., a 3GPP LTE system) is provided. In one example, the user resource structure combines the benefits of localized and distributed types of resource structures available in the current baseline 3GPP LTE (Release 8) specifications, and is especially suitable for operating in a fast time-varying channel. In another example, the non-cyclic evolving-type resource structure may be simplified to have no more than three stages: a band-type first stage, a partially evolved-type second stage and an interleaved-type third stage. Depending upon the target or average mobile speed and packet length, the resource structure may even have less than three stages.

Abstract: A method for operating a controller of a multiple input, multiple output communications system includes formulating an objective function according to a resource allocation for a user equipment (UE) and a mean square error expression, and updating the objective function to generate an updated resource allocation for the UE, a transmit beamforming vector to precode a transmission to the UE, and a receive beamforming vector to adjust a receiver to receive the precoded transmission. The method also includes transmitting allocation information about the resource allocation for the UE and the transmit beamforming vector to a communications controller serving the UE.

Abstract: Various example embodiments are disclosed. According to an example embodiment, a technique may include transmitting a message to allocate resources to a mobile station in a wireless network for an uplink acknowledgement channel, the acknowledgement channel including three subtiles including a subtile from each of three different tiles, each of the three tiles including a plurality of subtiles that includes at least one 2×3 subtile that includes two subcarriers by three Orthogonal Frequency Division Multiplexing (OFDM) symbols and at least one 3×2 subtile that includes three subcarriers by two OFDM symbols.

Abstract: It is an object to provide a wireless communication base station device that can prevent the decline of a system throughput due to the degradation of a utilization efficiency of a communication resource of a channel for carrying out a frequency diversity transmission when a frequency scheduling transmission and a frequency diversity transmission are concurrently carried out in multiple carrier communication. In the wireless communication base station device, a modulation unit (12) carries out modulation processing for Dch data after coding to generate a Dch data symbol. A modulation unit (22) carries out modulation processing for Lch data after coding to generate an Lch data symbol. An allocation unit (103) allocates the Dch data symbol and Lch data symbol to each sub-carrier composing an OFDM symbol and outputs the allocated sub-carrier to a multiplex unit (104).

Abstract: A data processing apparatus maps input symbols to be communicated onto a predetermined number of sub-carrier signals of an Orthogonal Frequency Division Multiplexed (OFDM) symbol. The data processor includes an interleaver memory which reads-in the predetermined number of data symbols for mapping onto the OFDM sub-carrier signals. The interleaver memory reads-out the data symbols on to the OFDM sub-carriers to effect the mapping, the read-out being in a different order than the read-in, the order being determined from a set of addresses, with the effect that the data symbols are interleaved on to the sub-carrier signals. The set of addresses are generated from an address generator which comprises a linear feedback shift register and a permutation circuit.

Abstract: A data processing apparatus maps input symbols to be communicated onto a predetermined number of sub-carrier signals of an Orthogonal Frequency Division Multiplexed (OFDM) symbol. The data processor includes an interleaver memory which reads-in the predetermined number of data symbols for mapping onto the OFDM sub-carrier signals. The interleaver memory reads-out the data symbols on to the OFDM sub-carriers to effect the mapping, the read-out being in a different order than the read-in, the order being determined from a set of addresses, with the effect that the data symbols are interleaved on to the sub-carrier signals. The set of addresses are generated from an address generator which comprises a linear feedback shift register and a permutation circuit. The linear feedback shift register has eleven register stages with a generator polynomial for the linear feedback shift register of R?i[10]=R?i-1[0]?R?i-1[2], and the permutation code forms, with an additional bit, a twelve bit address.

Abstract: A user terminal supports multiple spatial multiplexing (SM) modes such as a steered mode and a non-steered mode. For data transmission, multiple data streams are coded and modulated in accordance with their selected rates to obtain multiple data symbol streams. These streams are then spatially processed in accordance with a selected SM mode (e.g., with a matrix of steering vectors for the steered mode and with the identity matrix for the non-steered mode) to obtain multiple transmit symbol streams for transmission from multiple antennas. For data reception, multiple received symbol streams are spatially processed in accordance with the selected SM mode (e.g., with a matrix of eigenvectors for the steered mode and with a spatial filter matrix for the non-steered mode) to obtain multiple recovered data symbol streams. These streams are demodulated and decoded in accordance with their selected rates to obtain multiple decoded data streams.

Abstract: Systems and methods are provided for determining a number of spatial channels to use to transmit a data packet from a source node to a destination node. This determination can be made based on a Probability of Channel non-Correlation (PCC) function that is generated and updated by the source node based on feedback from the destination node. The PCC function indicates a probability of whether a plurality of spatial channels are non-correlated.

Abstract: An assignment section 101 determines communication resource assignment to communication terminals based on a transmission rate at which communication is possible for each subcarrier of each communication terminal, and instructs a buffer section 102 to output forward transmission data. In addition, the assignment section 101 instructs a frame creation section 103 to perform forward transmission data symbolization, and also outputs a signal indicating communication resource assignment to each communication terminal. The buffer section 102 holds forward transmission data, and outputs forward transmission data to the frame creation section 103 in accordance with instructions from the assignment section 101. The frame creation section 103 symbolizes a resource assignment signal and transmission data to create a frame, which it outputs to a spreading section 104.

Abstract: An apparatus and method for multiplexing packets for broadcast services in a mobile communication system based on orthogonal frequency division multiplexing (OFDM). The OFDM system has a transmission structure in which one slot includes at least two symbols, and each symbol includes a plurality of subcarriers. Different broadcast service packets received from at least two channels are multiplexed into one slot and a result of the multiplexing is transmitted. Overhead information of the channel packets multiplexed into the one slot is generated and transmitted.

Abstract: The present invention relates to a transmission apparatus for transmitting OFDM-signals comprising modulation means 4 for modulating said signals onto a plurality of subcarriers using a OFDM-modulation method, transformation means 5 for transforming said modulated signals into the time domain, and transmission means for transmitting said signals, whereby in said modulation means every M-th subcarrier is modulated, wherein M is an integer and M?2. The present invention also relates to a corresponding transmission method for transmitting OFDM-signals.