Abstract: Provided are a transmitting apparatus, a receiving apparatus and methods of controlling these apparatuses. The transmitting apparatus includes: a structurer configured to generate a transmission stream comprising an orthogonal frequency division multiplexing (OFDM) symbol and add signaling data to the transmission stream; and a transmitter configured to insert at least one pilot into the OFDM symbol, determine a number of active carriers to be included in a frequency spectrum, corresponding to the OFDM symbol into which the pilot is inserted, which exists in a preset spectrum mask, and map the OFDM symbol, into which the pilot is inserted, onto the active carriers of the determined number, and transmit the mapped OFDM symbol.

Abstract: Disclosed is a subframe scheduling method, which includes: a network side configures a transmission mode, wherein the transmission mode includes at least a multi-subframe scheduling transmission way; the network side selects a corresponding control information format according to the transmission mode, transmits Downlink Control Information (DCI) corresponding to the control information format, and then performs subframe scheduling according to the DCI. Further disclosed are a subframe scheduling system, a network device and a terminal. By means of the disclosure, the multi-subframe scheduling can be used under the condition in which user channel state information is relatively stable, thereby being able to reduce control signalling overheads, save system resources and improve the scheduling flexibility.

Abstract: In various embodiments, techniques are provided to determine channel characteristics of various communication systems such as OFDM systems or systems using a plurality of transmit antennas by using various sets of training symbols that produce zero cross-correlation energy. Channel communication can accordingly be simplified as the zero cross-correlation property allows for channel estimation without a matrix inversion.

Abstract: Techniques for fully-differential multi-phase scanning in capacitive fingerprint applications are described herein. In an example embodiment, a system comprises a capacitive fingerprint sensor array and a processing device coupled to the capacitive fingerprint sensor array. The processing device is configured at least to: scan the capacitive fingerprint sensor array in a fully-differential multi-phase mode; receive a plurality of measurements that represents a portion of finger on the capacitive fingerprint sensor array; and generate a fingerprint image for the portion of the finger based on the plurality of measurements. In some embodiments, a capacitive fingerprint sensor array may include receive (RX) electrodes and one or more reference electrodes configured to detect noise, where the one or more reference electrodes have width that is substantially equal to the width of the RX electrodes, but the one or more reference electrodes are disposed at a smaller pitch than the RX electrodes.

Abstract: An on-off keying (OOK) transmitter and communication method are provided. The OOK transmitter may include a data encoder configured to encode input data into a transmission sequence, a pulse shaper configured to generate pulses based on the transmission sequence, a bi-phase controller configured to generate a control signal to control a random change in phase, between two phases, of a carrier based on the transmission sequence, a bi-phased switch configured to randomly change a phase of the carrier generated by a voltage-controlled oscillator (VCO), based on the control signal, and a power amplifier (PA) configured to generate a transmission signal based on the generated pulses and the carrier with the randomly changed phase. The PA may be a bi-phasing PA, and the bi-phased switch may be included in the bi-phasing PA.

Abstract: Various examples of mechanisms, systems, methods, techniques and devices for dynamic rate adaptation in a vectored G.fast (G.9701) system are described. A first communication device may perform estimation of a residual noise to derive signal-to-noise ratio (SNR) loss for each carrier of one or more carriers with respect to a transmitting port of the first communication device. The residual noise may be an increased noise expected to be experienced by a second communication device when one or more other ports in a vectored group of a plurality of ports of the first communication device are switched off. The first communication device may adapt to the residual noise during time slots of one or more downstream symbol positions where the one or more other ports in the vectored group are switched off by dynamically changing bit-loading.

Abstract: Methods of data allocation and signal receiving, a wireless transmitting apparatus, and a wireless receiving apparatus are provided based on orthogonal frequency division multiplexing (OFDM) technology. The wireless transmitting apparatus obtains a data stream and allocates the data stream to a first sub-carrier set. Each of the first sub-carrier set and a second sub-carrier set has sub-carriers with opposite frequencies to each other, respectively. The second sub-carrier is emptied or allocated according the data stream allocated to the first sub-carrier set. The data stream is converted into an OFDM signal transmitted through a transmitting module. The wireless receiving apparatus includes a single branch receiver for receiving a radio frequency (RF) signal and outputting a baseband signal. Subsequently, the data stream is restored from the baseband signal.

Abstract: A bit interleaver, a bit-interleaved coded modulation (BICM) device and a bit interleaving method are disclosed herein. The bit interleaver includes a first memory, a processor, and a second memory. The first memory stores a low-density parity check (LDPC) codeword having a length of 64800 and a code rate of 2/15. The processor generates an interleaved codeword by interleaving the LDPC codeword on a bit group basis. The size of the bit group corresponds to a parallel factor of the LDPC codeword. The second memory provides the interleaved codeword to a modulator for 64-symbol mapping.

Abstract: An interconnection system comprising a plurality of nodes, each comprising at least two ports, and a plurality of links configured to interconnect ports among the nodes to form a hierarchical multi-level ring topology, wherein the ring topology comprises a plurality of levels of rings including a base ring and at least two hierarchical shortcut rings, and wherein each node connected to a higher-level shortcut ring is also connected to all lower-level rings including the base ring.

Abstract: Wireless networks that use orthogonal frequency division multiplexing require a receiving device to accurately acquire and maintain synchronization with a transmitting device with respect to carrier and sampling frequency for coherent demodulation. Described herein are techniques for enabling such synchronization using pilot signals with reduced transmission overhead.

Abstract: A method and network node of a first cellular network, for enabling mitigation of interference in the first cellular network caused by radio communication in a second cellular network. The network node obtains a total interference in a first cell of the first cellular network, and estimates a first interference contribution in the first cell caused by radio communication in the first cellular network. The network node then determines a second interference contribution in the first cell caused by radio communication in the second cellular network based on the estimated first interference contribution and the obtained total interference. The network node also utilizes the determined second interference contribution to counteract the interference in the first cell caused by the radio communication in the second cellular network.

Abstract: An electronic device for and method of determining a calibration code is provided. The electronic device includes a modem configured to receive a transmission signal, determine a calibration code that minimizes distortion of the transmission signal, and calibrate the distortion of the transmission signal using the calibration code.

Abstract: An interconnection network comprising a plurality of nodes arranged in a ring topology, wherein the nodes comprise a first node and a second node, and wherein the first node is not adjacent to the second node, a plurality of base links coupled to the nodes and configured to interconnect adjacent nodes to provide point-to-point communications between the adjacent nodes, and a first shortcut coupled to the first node and the second node, wherein the first shortcut is configured to provide a point-to-point communication between the first node and the second node, wherein the first node and the second node comprise gray code encoded addresses that are differed by 1-bit at a particular bit position, and wherein the gray code encoded addresses are node addresses of the first node and the second node encoded by a gray code algorithm that provides a 1-bit difference between successive integer values in a binary format.

Abstract: A wireless communication system is provided that includes a base station receiving a plurality of input signals that are selectively provided to a plurality of precoders. The precoders perform precoding operations on the input signals and output a first signal. The base station includes an algorithm that minimizes total transmit power per antenna under signal to interference and noise ratio (SINR) target constraints or maximizes the SINR under a sum of power constraint so as to determine power allocation and obtain efficient precoders. A number of mobile receiver units receive the first signal and performs their respective operations to extrapolate the linear estimate of the input signals.

Abstract: A signal transmission approach comprises encoding a source signal (comprising source symbols) to generate a corresponding encoded signal. The encoded signal is modulated by mapping each source symbol to a respective signal constellation point of an applied signal constellation to generate a modulated signal. The modulated signal is pre-distorted based on a distortion estimate to generate a pre-distorted signal. The pre-distorted signal is filtered to generate a filtered signal. The filtered signal is frequency translated and amplified to generate a transmission signal for transmission via an uplink channel of a satellite communications system. To increase throughput, the source signal is processed through the apparatus and the resulting transmission signal is generated at a Faster-than-Nyquist (FTN) symbol rate and with a tight frequency roll-off. The modulated signal is pre-distorted based on a distortion estimate relating to the nonlinearity and the filters applied before and/or after the pre-distorter.

Abstract: A method of communicating data in a wireless telecommunications system between plural base stations and plural terminal devices using plural Orthogonal Frequency Division Multiplex, OFDM, sub-carriers spanning a first frequency bandwidth. The method includes: communicating data between a first base station and a first terminal device using a first OFDM sub-carrier group distributed across the first frequency bandwidth, communicating data between a second base station, geographically separated from the first base station, and a second terminal device using a second OFDM sub-carrier group distributed across a second frequency bandwidth, the second frequency bandwidth being smaller than and within the first frequency bandwidth; and communicating control-plane data between the first base station and the first terminal device using a combination of the first and second groups of the OFDM sub-carriers.

Abstract: A method and apparatus for encoding a block-based communication system header. A physical layer header and a medium access control header of the block-based communication system header are encoded to generate parity bits, wherein the PHY layer header includes at least cyclic prefix mode bits. Parity bits are appended to the PHY layer header and the MAC layer header to generate a bit vector. The bit vector is divided into at least two data blocks, wherein a first data block includes at least the CP mode bits. A predefined number of tail bits are appended to each data block. The two data blocks are mapped into at least two symbols, wherein the first data block is mapped to a first symbol, such that the first symbol is a first header symbol being transmitted.

Abstract: A transmitter comprises a symbol mapper operable to map a frame of bits to a frame of symbols, where the symbols correspond to a determined modulation scheme, and circuitry operable to convert the frame of symbols to a physical layer signal and transmit the physical layer signal onto a communication medium. The circuitry is operable to process the physical layer signal such that a first portion of the physical layer signal is a first type of signal (e.g., a linear signal and/or non-ISC signal) and a second portion of the physical layer signal is a second type of signal (e.g., nonlinear signal and/or ISC signal). The first portion of the physical layer signal may comprise a header, a preamble, and/or a payload of the frame. The second portion of the physical layer signal may comprise a header, a preamble, and/or a payload of the frame.

Abstract: A receiver architecture and method recovers data received over an optical fiber channel in the presence of cycle slips. In a first cycle slip recovery architecture, a receiver detects and corrects cycle slips based on pilot symbols inserted in the transmitted data. In a second cycle slip recovery architecture, a coarse cycle slip detection is performed based on pilot symbols and a cycle slip position estimation is then performed based on carrier phase noise. The receiver compensates for cycle slips based on the position estimation.

Abstract: The present invention provides a receiver, a transmitter, a transmitter feedback device, and corresponding methods. The feedback device includes: a multi-channel frequency selection band-pass circuit, configured to receive a multi-frequency band feedback signal, and output a feedback signal of each frequency band in a time-division manner; a feedback local oscillator, configured to provide feedback local oscillation corresponding to each frequency band in a time-division manner; a mixer, configured to mix the feedback signal of each frequency band from the multi-channel frequency selection band-pass circuit and the feedback local oscillation corresponding to each frequency band from the feedback local oscillator, and output an intermediate frequency signal of each frequency band in a time-division manner. A solution in which only one set of signal processing channels is used to process the signals of multiple frequency bands in the uplink, the downlink or both the uplink and downlink is provided.

Abstract: A method is described for uplink transmission in a wireless communication system. A user equipment determines whether to transmit or drop a sounding reference signal (SRS) on a last symbol in an ith subframe. The determination is performed if multiple timing advance groups (TAGs) are configured and if a portion of the last symbol of the ith subframe for the SRS transmission toward the a serving cell in a first TAG is overlapped with an (i+1)th subframe for transmitting an uplink channel toward a second serving cell in a second TAG.

Abstract: Method and apparatus for base stations and subscriber units allows soft handoff of a CDMA reverse link utilizing an orthogonal channel structure. Subscriber units transmit an orthogonally coded signal over a reverse link to the base stations. A given base station provides timing control of the timing offset of the reverse link signal. Based on at least one criterion, an alignment controller determines that the given base station should hand off timing control to another base station, and a soft handoff process ensues. In response to a command or message for soft handoff of the subscriber unit from the given base station to another base station, the subscriber unit makes a coarse timing adjustment to the timing of the coded signal. The subscriber unit may make fine timing adjustments based on feedback from the base station controlling timing. Multiple base stations may provide power control feedback to the subscriber unit.

Abstract: Provided is a wireless communication mobile station device by which a throughput can be improved in multicarrier communication. In the device, a group control section (107) controls a subcarrier group, of which CQI is to be reported, among a plurality of subcarrier groups to periodically change, by following pattern information. For instance, the group control section (107) changes the subcarrier group whose CQI is to be reported, by frame or TTI (Transmission Time Interval). Furthermore, the group control section (107) specifies the subcarrier group whose CQI is to be reported, to an SINR detecting section (108) and a CQI generating section (109).

Abstract: Various disclosed embodiments include methods and systems for communication in a wireless communication system. A method comprises receiving a signal corresponding to a plurality of modulated signals, each of the plurality of modulated signals corresponding to a unique electronic device. The method comprises filtering the received signal with a plurality of filters, each of which is matched to a corresponding filter in a respective electronic device to obtain a filtered signal for the respective electronic device. The method comprises performing a fast Fourier transform (FFT) operation on the filtered signal to obtain demodulated data corresponding to the respective electronic device.

Abstract: A method and device for transmitting an uplink signal in a wireless communication system is provided. A user equipment transmits a physical uplink shared channel (PUSCH) on a SRS subframe for a first serving cell to a base station if a SRS transmission on the SRS subframe for the first serving cell is overlapped with an uplink transmission for a second serving cell. The PUSCH is transmitted on remaining orthogonal frequency division multiplexing (OFDM) symbols in the SRS subframe except a single OFDM symbol reserved for the SRS transmission regardless of whether a SRS is transmitted on the single OFDM symbol or not.

Abstract: A radio station, a radio terminal, and a method for synchronization timer control are provided that can reduce a delay as much as possible until uplink signal resynchronization is done in a case where a plurality of cell groups exist.

Abstract: A method operates to transmit a data signal by a transmission unit of a wireless multiple-input/multiple-output (MIMO) communication system. The communication system includes the transmission unit and a reception unit, the transmission unit having a plurality of transmission antennas and the reception unit having a plurality of reception antennas. The method includes performing a first transmission of a data signal, the first transmission including transmitting the data signal by each one of the plurality of transmission antennas, and performing a second transmission of the data signal at a time later than the first transmission, the second transmission including transmitting at least one spectrally modified signal variant of the data signal by at least one antenna of the plurality of transmission antennas.

Abstract: In a method of adapting a control channel in a network node in a communication system, providing (S20) a control format indicator for the control channel, and dynamically determining and providing (S10) control channel redefinition information, which control channel redefinition information together with said control format indicator provides a redefined control channel. Subsequently the control channel is adapted (S30) based on said control format indicator and said control channel redefinition information to provide a redefined control channel for signaling to said at least one user equipment, Finally, scheduling (S40) user equipment in a sub frame based on the redefined control channel.

Abstract: A communication apparatus comprises an inserter that inserts an element having a value of 0 or nearly 0 into a predetermined position of a modulated signal to generate inserted data; an operator that adds a pilot signal comprising a data series of which the elements at the positions corresponding to the predetermined positions in the modulated signal are multiplied by a first amplitude coefficient and the elements other than the elements multiplied by the first amplitude coefficient are multiplied by a second amplitude coefficient to the inserted data to generate a post-operation data; an IFFT unit that performs IFFT on the post-operation data; and a transmitter that generates a baseband signal based on the post-operation data on which the IFFT is performed and transmits a transmission signal generated from the baseband signal.

Abstract: Wireless communication wherein channel estimation accuracy is improved while keeping the position of each bit in a frame, even when a modulation system having a large modulation multiple value is used for a data symbol. An encoding operation encodes and outputs transmitting data (bit string) and a bit converting operation converts at least one bit of a plurality of bits constituting a data symbol to be used for channel estimation, among the encoded bit strings, into ‘1’ or ‘0’. A modulating operation modulates the bit string inputted from the bit converting operation by using a single modulation mapper and a plurality of data symbols are generated.

Abstract: Disclosed in some examples is a method of channel access by a wireless device in a wireless network by determining whether there is network traffic associated with a preamble of a first type and whether there is network traffic associated with a preamble of a second type, wherein the wireless device is not capable of decoding the preamble of the second type, and wherein determining that there is network traffic associated with a preamble of the second type includes determining that an energy level of the channel is above a threshold for a period of time, the first and second preamble types being different lengths; and sending a packet with a preamble of the first type, responsive to determining that no network traffic is detected associated with the preamble of the second type or network traffic associated with a preamble of the first type for the period of time.

Abstract: A method for receiving and removing co-channel interference from one or more received signals that comprise different symbol or chipping rates can comprise receiving a first composite signal and a second composite signal. The method can also comprise sampling the first composite signal and the second composite signal at a particular sampling rate that is sufficient to recover signal data from both the first composite signal and the second composite signal. Further, the method can comprise estimating from the second composite signal an estimated cross-coupled second signal within the first composite signal. The estimated cross-coupled second signal is estimated from at least the second composite signal at the particular sampling rate. Further still, the method can comprise recovering a substantially decoupled first data signal by removing at least a portion of the co-channel interference caused by the estimated cross-coupled second signal from the composite first signal.

Abstract: Provided is a precoding method for generating, from a plurality of baseband signals, a plurality of precoded signals to be transmitted over the same frequency bandwidth at the same time, including the steps of selecting a matrix F[i] from among N matrices, which define precoding performed on the plurality of baseband signals, while switching between the N matrices, i being an integer from 0 to N?1, and N being an integer at least two, generating a first precoded signal z1 and a second precoded signal z2, generating a first encoded block and a second encoded block using a predetermined error correction block encoding method, generating a baseband signal with M symbols from the first encoded block and a baseband signal with M symbols the second encoded block, and precoding a combination of the generated baseband signals to generate a precoded signal having M slots.

Abstract: An optical phase compensation device included in an optical receiver employing an intradyne detection method, includes a first optical phase error calculator configured to calculate a first optical phase error by averaging signal symbols of a first number of input main signals, a second optical phase error calculator configured to calculate a second optical phase error by averaging signal symbols of a second number of the main signals, wherein the second number is smaller than the first number, and a subtractor configured to subtract, from optical phase components of the main signals, one of a difference between the first optical phase error and the second optical phase error and a value obtained by multiplying the difference by a gain relative to the difference.

Abstract: A method and apparatus are provided for transmitting one or more symbols in a multiple antenna wireless communication system. Subcarriers from one or more symbols are interleaved across a plurality of antennas. The symbols may be, for example, long or short training symbols based on a single-antenna long or short training symbol, respectively, and wherein each subsequent subcarrier from the single-antenna training symbol is positioned in a training symbol for a logically adjacent antenna. One or more additional subcarriers may be inserted in at least one of the plurality of symbols to allow nulled subcarriers to be estimated using an interpolation-based channel estimation technique. The remaining portions of a header, as well as the data sequences of a packet, may also be diagonally loaded.

Abstract: The present invention relates a method in which a base station transmits a downlink signal by using a plurality of layers comprises the steps of: multiplexing and transmitting dedicated reference signals for the plurality of layers on the basis of a reference signal pattern, wherein 24 resource element positions comprised in the reference signal pattern are set as 6 groups, the 6 groups are set as 2 high-level groups, the reference signal for the plurality of layer is split and placed in the 2 high-level groups, and the reference signal for 2 or more layers placed in the same group is subjected to code-division multiplexing.

Abstract: A receiver architecture and method recovers data received over an optical fiber channel in the presence of cycle slips. In a first cycle slip recovery architecture, a receiver detects and corrects cycle slips based on pilot symbols inserted in the transmitted data. In a second cycle slip recovery architecture, a coarse cycle slip detection is performed based on pilot symbols and a cycle slip position estimation is then performed based on carrier phase noise. The receiver compensates for cycle slips based on the position estimation.

Abstract: A process and apparatus (called Receiver Calibration) are described, that allows the determination of responses of a receiver to signals, the property values of which are known. The signals with known property values are supplied to the receiver via guided waves, i.e. in a controlled environment. The Receiver Calibration is suitable for calibration of a wide variety of devices.

Abstract: Systems, methods, and devices for wireless communication. In one aspect, an apparatus for wireless communication is provided. The apparatus includes a receiver configured to receive a wireless signal comprising a packet. At least a portion of the wireless signal may be received over a channel with a channel bandwidth of at least approximately five hundred megahertz. The packet may be formed from at least one orthogonal frequency-division multiplexing (OFDM) symbol comprising at least one hundred and twenty-eight tones. The apparatus further comprises a processor configured to evaluate the wireless signal. The processor may comprise a transform module configured to convert the at least one OFDM symbol into a frequency domain signal.

Abstract: A system including a first gain module and a second gain module. The first gain module is configured to receive first signals generated based on a plurality of data streams mapped to a plurality of antennas including a first antenna and a second antenna, and to apply a first gain corresponding to the first antenna to the first signals. The second gain module is configured to receive second signals generated based on the plurality of data streams, and to apply a second gain corresponding to the second antenna to the second signals. The second signals are different than the first signals. The second gain is different than the first gain.

Abstract: A method for transmitting uplink response signals, base station, mobile station and communication system, includes judging whether to use a downlink secondary component carrier to transmit data to a mobile station; if the judging result is positive, allocating resources according to the number of transmission blocks for transmitting the downlink data in the secondary component carrier, accordingly the mobile station is able to use the resources corresponding to a preconfigured primary component carrier and the resources allocated to the secondary component carrier to select uplink resources for transmitting response signals.

Abstract: Techniques and mechanisms for exchanging communications which each represent a respective combination of data and clock signaling. In an embodiment, encoder logic generates a first signal pair, including encoding a first differential data signal pair with a first clock signal of a differential clock signal pair. The encoder logic further generates a second signal pair, including encoding a second differential data signal pair with a second clock signal of the same differential clock signal pair. In another embodiment, decoder logic receives and decodes the first signal pair and the second signal pair, wherein the decoding generates the first differential data signal pair, the second differential data signal pair and a clock signal.

Abstract: The present invention provides a signal sending method, device, and system. The method includes: A sender performs signal multiplexing processing on a first service data block in service data blocks to be sent and uplink control information, and performs channel interleaving processing on mixed data generated after the signal multiplexing processing, to generate a mixed data block; the sender performs signal spatial multiplexing processing on the mixed data block and remaining service data blocks in the service data blocks to be sent except the first service data block to generate a spatially multiplexed signal, and then sends the spatially multiplexed signal to a receiver through a PUSCH channel. The present invention solves the problem of signal transmission over the PUSCH channel after a MIMO technique is introduced in an LTE-A system.

Abstract: A wireless communication device (‘device’) is configured to generate an OFDM/A packet that includes at least one OFDM/A symbol that includes at least one SIG having SIG information modulated on only even (or odd) sub-carriers and does not include any information modulated on odd (or even) sub-carriers of a set of OFDM/A sub-carriers. The set of OFDM/A sub-carriers may be all or less than all of available sub-carriers. The device may generate the packet to include a preamble and a payload such that the payload, which may be composed of at least one additional OFDM/A symbol, includes data modulated on some or all of the sub-carriers of the set of OFDM/A sub-carriers. The device can modulate and transmit SIG information and data differently within the preamble and the payload (e.g., with higher ordered modulation or MCS for the data and less power per sub-carrier than for the preamble).

Abstract: Methods and systems for mitigating interference or estimating a covariance matrix in a communication system are disclosed. A method of demodulating a received signal in a communication system can include receiving a first plurality of waveforms, estimating a covariance matrix based on the first plurality of waveforms, determining a spatial filter based on the estimated covariance matrix, receiving a second plurality of waveforms, generating at least one filtered waveform by applying the spatial filter to the second plurality of waveforms, and demodulating the at least one filtered waveform.

Abstract: The present invention provides a correlator and a demodulation device including, first and second filter sections having different non-overlapping pass-frequency characteristics, first and second delay circuits that delay the signals output from the first and second filter section by one effective OFDM symbol period, first and second complex conjugate circuits that take the complex conjugates of the delayed signals, first and second complex operation sections that compute the complex-multiplies of the signals from the first and second filter sections and the respective signals for the first and second complex conjugate circuits, first and second moving average processing sections that take moving averages of GI lengths, proportion determination circuit that compares the maximum values of the autocorrelations from each of the first and second moving average processing circuits, and selection-combination circuit that selects the autocorrelation having the largest maximum value based on the comparison result.

Abstract: Techniques are presented herein to encode information bits. The information bits are partitioned into at least two groups based on inherent reliability and immunity to channel impairments of the respective bits. Each of the groups of information bits is encoded with a different coding strength. The resulting code word may be stored in a storage media or transmitted in a communication channel.

Abstract: A system is described for processing data of at least one location aware devices for obtaining geo-information. The system comprises an input means for obtaining vector-based data from at least one location aware devices, a data processor for inserting information from the vector-based data into a raster-based data structure so as to derive geo-information based on the raster-based data structure. A corresponding method as well as corresponding computer program products also are described.

Abstract: A multi-carrier communication system such as an OFDM or DMT system has nodes which are allowed to dynamically change their receive and transmit symbol rates, and the number of carriers within their signals. Changing of the symbol rate is done by changing the clocking frequency of the nodes' iFFT and FFT processors, as well as their serializers and deserializers. The nodes have several ways of dynamically changing the number of carriers used. The selection of symbol rate and number of carriers can be optimized for a given channel based on explicit channel measurements, a priori knowledge of the channel, or past experience. Provision is made for accommodating legacy nodes that may have constraints in symbol rate or the number of carriers they can support.

Abstract: Methods and apparatus are provided for inserting data symbols and pilot symbols in an OFDM (orthogonal frequency division multiplexing) transmission resource utilizing frequency hopping patterns for the data symbols and/or the pilot symbols. Data symbols and pilot symbols are allocated for down link (base station to mobile station) and up link (mobile station to bases station) transmission resources in a two-dimensional time-frequency pattern. For each antenna of a MIMO-OFDM (multiple input multiple output OFDM) communication system, pilot symbols are inserted in a scattered pattern in time-frequency and data symbols are inserted in an identical frequency-hopping pattern in time-frequency as that of other antennas.