Abstract: A semiconductor device comprises sampling logic, comprising: input sample path selection logic arranged to enable at least one input sample path; sampler logic arranged to receive and sample an input data signal in a serial data stream in accordance with a phase of the at least one enabled input sample path; and transition detection logic arranged to detect transitions within the received input data signal. The input sample path selection logic is further arranged, upon detection of a transition within the received input data signal, to determine if the phase of the at least one input sample path is a phase having a largest window between logic values; and if it is determined that the phase of the at least one input sample path is not the phase having a largest window between logic values, to enable at least one input sample path comprising a more appropriate phase.

Abstract: A communication method includes detecting at a gate drive unit a change of state of a command signal that is received via a command link of the gate drive unit and initiating, responsive to the change of state of the command signal, a blanking period in which the gate drive unit will process as incoming data any further changes of state of the command signal. The method also includes receiving incoming data at the gate drive unit, by processing modulations of the command signal, within the blanking period.

Abstract: Communication systems may benefit from an HSPA MIMO receiver configured for receipt of an imbalanced transmit signal, as well as a method for operating the receiver. According to certain embodiments, a method can include receiving a multiple-input multiple-output system communication signal comprising at least one primary signal at a first power level from a first antenna and a secondary signal at a second power level different from the first power level from a second antenna. The method can also include estimating at least one parameter of the communication signal. The method can further include applying the at least one parameter as estimated to calculate linear minimum mean square error coefficients. The method can additionally include applying the linear minimum mean square error coefficients to process the communication signal.

Abstract: A system and method are disclosed for performing on die jitter tolerance testing. A set of clocks are generated based on an input signal. The set of clocks include in an in-phase signal based on the data switching edge of the input signal. Additionally, the set of clocks include an inverted clock phase shifted by 180 degrees, and a pair of clocks phase shifted positively and negatively by a certain number of degrees, ?. Data input is sampled based on the inverted clock and the two phase shifted clocks. The eye opening of the input signal can be determined based on whether each of the inverted clock and the two phase shifted clocks sample the correct data from the input signal at various ? values.

Abstract: Embodiments of this invention describe a method to reduce the effective inter carrier spacing between the sub-carriers of wireless, wired or optical transmissions and thereby increase the spectral efficiency of the communication system. Signal transmitted from multiple transmit chains are shifted in frequency at the transmitter. At the receiver a plurality of receive chains is used, the received signals are similarly shifted in frequency and used to reduce the inter carrier interference. Embodiments also describe a method for Full Duplex communication where the transmitters transmit using different frequency shifts. The receiver receives the transmitted signal and an echo of it's transmission. As the received transmission is shifted in frequency from it's transmission, it can cancel out the echo and receive the intended signal.

Abstract: To compensate for roll-off while estimating a communication channel, an estimate of the channel is provided using a signal transmitted via the communication channel. The pilot tones positioned along the edges of the estimated channel are divided by the corresponding pilot tones of the received signal to generate a first number of ratios. An algorithm is thereafter applied to the first number of ratios to generate a second number of ratios associated with the non-pilot tones positioned along the edges of the estimated channel. Next, numbers that are inverse of the first and second number of ratios are applied to the pilot and non-pilot tones positioned along the edges of the estimated channel to compensate for the roll-offs in the estimated channel.

Abstract: A method and apparatus are disclosed for controlling a buffer in a digital audio broadcasting (DAB) communication system. An audio encoder marks a frame as “dropped” whenever a buffer overflow might occur. Only a small number of bits are utilized to process a lost frame, thereby preventing the buffer from overflowing and allowing the encoder buffer-level to quickly recover from the potential overflow condition. The audio encoder optionally sets a flag that provides an indication to the receivers that a frame has been lost. If a “frame lost” condition is detected by a receiver, the receiver can optionally employ mitigation techniques to reduce the impact of the lost frame(s).

Abstract: This invention discloses a method for communications faster than the Nyquist rate (FTN) and faster than the Shannon rate which method is Quadrature Layered Modulation (QLM). QLM properties include scaling the data symbol pulses to maintain the same error rate performance for all rates. QLM alternatively considers the increase in the data symbol rate to be a layering of additional communications over the same link. The Shannon bound is a limit on the capacity of a communication link when transmitting data symbols at the Nyquist rate. QLM observes one can communicate at FTN to transmit more information than the Shannon rate since the Nyquist rate captures the information in a frequency band and does not constraint the information. These properties describe QLM and a separate math proof-of-concept is disclosed. Implementation and performance data demonstrate QLM can support communications data rates which are at least double the Shannon rate.

Abstract: Certain aspects of the present disclosure relate to a method for compressed sensing (CS). The CS is a signal processing concept wherein significantly fewer sensor measurements than that suggested by Shannon/Nyquist sampling theorem can be used to recover signals with arbitrarily fine resolution. In this disclosure, the CS framework is applied for sensor signal processing in order to support low power robust sensors and reliable communication in Body Area Networks (BANs) for healthcare and fitness applications.

Abstract: A method for efficiently transmitting and receiving downlink control information is disclosed. The method includes, at a base station, receiving feedback information including a precoding matrix index (PMI) from a user equipment (UE) and transmitting precoding information having a predetermined bit number according to the number of antenna ports and a transmission mode of the base station. The precoding information of a predetermined transmission mode in the precoding information includes confirmation information indicating that the base station uses a PMI which is recently received from the UE.

Abstract: A mechanism is provided for dynamically adjusting DC offset at the time of deviation from DC balance ½ (DC level) in a data pattern including long-period consecutive bits generating DC offset in a section of data. A receiver circuit unit of an LSI having a serializer/deserializer arrangement for performing high-speed serial transmission includes an offset adjusting circuit. The offset adjusting circuit calculates DC balance in an arbitrary section of data by averaging received serial data. Based on comparison between a DC level and the DC balance obtained by averaging the received data, offset is shifted toward the H side when the DC balance exists on the H side from the DC level, and shifted toward the L side when the DC balance exists on the L side.

Abstract: A clock data recovery circuit includes a ring oscillator, an oscillation control circuit unit to start or stop the ring oscillator according to existence or absence of a PWM signal, a counter circuit unit to count pulse signals to hold N bits of count value, a register circuit unit which is configured to transmit upper M bits of count value, as a reference count value, in response to a transmission signal, a comparison circuit unit to output a timing clock when the count value exceeds the reference count value, and a transmission control circuit unit to be synchronized with a rising timing of the PWM signal to generate the transmission signal and a reset signal for resetting the counter circuit unit.

Abstract: The present invention discloses a type of LNB frequency down conversion integrated circuit. The present invention frequency-down-converts the RF signal with the Quadrature local oscillation signal (LO) and Quadrature Mixer. Then the 90 degree phase-shifting of the quadrature intermediate frequency (IF) signal after mixed is done by the use of passive Polyphase filter. The present invention further discloses a LNB frequency down conversion chip, a LNB frequency down circuit adopting the LNB frequency down conversion chip circuit and a method of LBN frequency down. The invention ensures the elimination of the minor image signal and the realization of the minor image suppression function.

Abstract: A mechanism for dynamic skew correction in a multi-lane communication link includes a receiver unit including, for each of the lanes, a first-in first-out (FIFO). The FIFO may store received symbols to locations pointed to by a write pointer and output to downstream logic, symbols stored at locations pointed to by a read pointer. The receiver may also include a symbol drop unit that disables the write pointer in response to receiving a start alignment symbol, and enables the write pointer in response to receiving an end alignment symbol. The receiver also includes an alignment unit that disables the read pointer in response to detecting that the end symbol has been received at least one lane but not all lanes. In addition, the alignment unit may enable the read pointer in response to a determination that the end symbol has been received on all lanes.

Abstract: In a data processing device and a method for analyzing stability of the data processing device, one or more sets of equalization parameters and a predetermined bit error ratio (BER) are received. Times and voltages of data points that represent a waveform of an electronic signal generated by the data processing device are read, and an output type of the electronic signal is selected to obtain a time interval of outputs of the electronic signal. Optimal equalization parameters are selected from the one or more sets of equalization parameters to compute a sample interval. Interfering voltages of the electronic signal are computed to select a frequency which is equal to the predetermined BER, and the interfering voltages corresponding to the selected frequency are obtained. An eye pattern is established using the interfering voltages corresponding to the selected frequency, and a determination is made according to the eye pattern.

Abstract: A system and method of frequency offset compensation are disclosed for a wireless system between a fast moving radio terminal associated with a locomotive and a stationary radio terminal associated with a base station. The present invention utilizes advanced frequency offset prediction to quickly track Doppler Shift caused by a fast moving locomotive. In one embodiment according to the present invention, the frequency offset prediction is based on a first plurality of coarse frequency offsets, first-order derivatives of the first plurality of coarse frequency offsets, and second-order derivatives of the first plurality of coarse frequency offsets. In another embodiment according to the present invention, the frequency offset prediction is based on a plurality of previous frequency offsets according to a Doppler shift model.

Abstract: A method for processing at least one polarization type of at least one wireless signal by a communication unit operably couplable to an antenna arrangement that comprises at least two orthogonally polarized antenna elements. The method comprises processing at least one signal radiated by at least one first antenna element of the antenna arrangement; and processing the at least one signal where processing comprises at least applying at least one digital complex scaling operation on the at least one signal radiated by at least one second antenna element of orthogonal polarization to the at least one first antenna element of the antenna arrangement thereby radiating at least one wireless signal of at least one non-native polarization type.

Abstract: A receiver and a transmitter that copes with interference in a super-regenerative communication system, and a method of using the receiver and the transmitter, are provided. A super-regenerative receiver includes a resonance frequency adjusting unit configured to adjust a resonance frequency associated with a filtering band of a transmission signal that is received from a transmitter. The super-regenerative receiver further includes an oscillation signal generating unit configured to generate an oscillation signal, using a positive feedback amplification, based on the resonance frequency and the transmission signal. The super-regenerative receiver further includes an oscillation characteristic detecting unit configured to detect a characteristic of the oscillation signal. The super-regenerative receiver further includes a determining unit configured to determine whether interference is included in the transmission signal based on the characteristic of the oscillation signal and the resonance frequency.

Abstract: A radio base station (eNB 1) receives an SRS from the radio terminal (UE 2A) and SRSes from radio terminals (UE 2B through UE 2D), and calculates, on the basis of at least one of the SRSes from the radio terminal (UE 2A) and from the radio terminals (UE 2B through UE 2D), a reception weight that is to be used for wireless communication with the radio terminal (UE 2A).

Abstract: System and methods for a multicarrier communication system, which includes a first and second transceivers, to transmit, from the first transceiver to the second transceiver, a first initialization message indicating an impulse noise protection value. The system also transmits, from the second transceiver to the first transceiver, a second initialization message comprising information that indicates a number of repeated DMT symbols, the number of repeated DMT symbols being greater than the impulse noise protection value. The system further transmits, from the first transceiver to the second transceiver, a third initialization message, wherein the first transceiver modulates at least one message bit onto repeated DMT symbols, wherein the number of repeated DMT symbols is indicated in the second initialization message transmitted from the second transceiver to first transceiver.

Abstract: Disclosed herein is a data receiving circuit including a transmitting section configured to transmit an identifying signal used to identify a state of connection of the data receiving circuit, the identifying signal making potential transitions periodically, in an in-phase signal via a transmission path having AC coupling to a data transmitting circuit for transmitting data in a differential signal via the transmission path.

Abstract: A soft decision value generation circuit capable of reducing amount of calculation and hardware scale for generating a soft decision value. The soft decision value generation circuit includes: a phase rotation unit rotating phases of received symbols after coherent detection; addition units calculating, by using the phase-rotated received symbols, absolute values of soft decision values for soft decision value candidates restricted in advance; minimum value selection units selecting minimum values out of the absolute values of the soft decision values; sign reflection units reflecting, based on the phases of the received symbols after the phase rotation, sign information to the minimum values; and soft decision value correction units multiplying outputs of the sign reflection units by a coefficient depending on a noise variance value and an amplitude value of a modulation symbol.

Abstract: A system and method for blind equalization of a QAM signal. Equalization is achieved using an algorithm characterized by cost function that is a function the Euclidian distance, e.g. the minimum Euclidian distance, between points of the constellation associated with the QAM signal, i.e. the distance between symbols.

Abstract: The invention relates to a method of receiving a signal corresponding to a multicarrier signal transmitted via at least one transmission channel, the method comprising an estimation step (11) of estimating said channel and delivering overall information about said channel in the frequency domain, referred to as a “frequency response” and comprising frequency samples. According to the invention, such a method also comprises: a sharing step (12) of sharing said frequency samples in at least two frequency sample vectors; a transform step (13) of transforming said frequency sample vectors from the frequency domain to a transform domain and delivering, for at least one frequency sample vector, a partial response of said channel in said transform domain; and a feedback step (14) of transmitting a return signal back to said transmitter, the return signal conveying samples extracted from said partial responses and representative of said channel in said transform domain.

Abstract: A method for transmitting and receiving a codebook subset restriction bitmap is provided. The Codebook Subset Restriction (CSR) bitmap transmission method of an evolved Node B (eNB) in transmission mode 9 for communication with 8 antenna ports includes generating a CSR bitmap including bits corresponding to restricted precoding matrix indicators and rank indicators that are not allowed for reporting and transmitting the CSR bitmap to a User Equipment (UE). The CSR bitmap comprises 53 bits corresponding to a first codebook and 56 bits corresponding to a second codebook, the 53 bits corresponding to a first codebook comprise 16, 16, 4, 4, 4, 4, and 1 bits for layers 1, 2, 3, 4, 5, 6, 7, and 8, respectively, and the 56 bits corresponding to a second codebook comprise 16, 16, 16 and 8 bits for layers 1, 2, 3, and 4, respectively.

Abstract: The present invention provides a method and apparatus for initiating a multiple input multiple output (MIMO) communication. The method and apparatus includes processing that begins by transmitting a frame formatted in accordance with a default MIMO active transmitter-receiver antenna configuration to a target receiver. The processing continues by receiving at least one response frame from the target receiver. The processing continues by determining a number of receiver antennas of the target receiver from the at least one response frame.

Abstract: A method of processing broadcast data includes performing RS encoding and CRC encoding on mobile service data to generate an RS frame belonging to an ensemble including a signaling information table including access information of the mobile service data and identification information for identifying a stream where keys to decrypt the mobile service data are obtained, mapping a portion of data in the RS frame to a group including known data sequences, FIC data, and TPC data, wherein the FIC data includes information for rapid mobile service acquisition, and the TPC data includes FIC version information for indicating an update of the FIC data; and transmitting a broadcast signal including the group.

Abstract: A signal received via a fading channel is decoded in radio frequency receiver by first demodulating the signal to a baseband signal, and serial to parallel converting the baseband signal to a precoded signal. Then, a channel matrix is estimated from the precoded signal, and symbols are detected in the precoded signal using the channel matrix. The decoding uses probabilistic data association. The detecting initializes a probability distribution for each symbol, and selects an ordering in which to update the probability distributions. The probability distribution for each symbol are updated according to the ordering, until a termination condition is reached, and then demapped and parallel to serial converted to estimate a sequence of bits used to generate the signal.

Abstract: A method for acquiring channel state information is disclosed in the present invention, including: a user equipment (UE) reporting codebook index information and information about the total number of layers to a base station (eNB), wherein the codebook index information includes one of the following information: class 2 codebook index l; and class 1 codebook index i and index parameter j; and after receiving the codebook index information and information about the total number of layers sent by the UE, the base station obtaining a codeword in the manner of inquiring of a preset codebook list or in the manner of inquiring of the preset codebook list in conjunction with calculation according to the codebook index information and information about the total number of layers. A system for acquiring channel state information is also disclosed in the present invention.

Abstract: Methods and systems for multi-path video and network channels may comprise a communication device comprising a wideband path (WB) and a narrowband path (NB), wherein the WB may be operable to receive a plurality of channels and the NB may be operable to receive a single channel. Video channels and a network channel may be received in the WB when the device is operating in a first stage. Video channels and a network channel may be received in the WB and the network channel may also be received in the NB when the device is operating in a second stage. The network channel may be received in the NB when the device is operating in a third stage. The reception of the network channel from both the WB and the NB may enable a continuous reception of the network channel in a transition between the first and third stages.

Abstract: A demodulation unit demodulates a received signal in which carrier wave of a navigation message that is modulated according to a BPSK modulation scheme are included. An error detection processing unit performs an error detection process on the demodulation result using an error detection bit that is included in the demodulation result. A verification word generator generates a verification word using the demodulation result and a check code when an error is detected by the error detection process, the check code being determined in advance for each bit of the navigation message based on a predetermined encoding rule. An estimation unit estimates an originating bit of a demodulation error by comparing the verification word generated by the verification word generator with a verification word table stored in a storage unit. A correction unit corrects the demodulation result by inverting the bit values of bits subsequent to the estimated originating bit.

Abstract: The present disclosure relates to channel state feedback in a communication system. The method includes obtaining a reference signal from an access point; deriving a rank indication, a codebook subset selection indication and a precoding matrix index based on the obtained reference signal; sending a first feedback message conveying the rank indication and the codebook subset selection indication, and sending a second feedback message conveying the precoding matrix index, to the access point; and receiving, from the access point, data precoded by a matrix derived based on the rank indication, the codebook subset selection indication and the precoding matrix index.

Abstract: The present disclosure provides a method and apparatus for transmitting the beamforming matrix. The method includes calculating the maximum value mv(k) of the real part and imaginary part of the elements in subcarrier's beamforming matrix; carrying out a M bits quantization to mv(k) and obtaining the quantization amplitude mv(k), calculating the linear part mvlin(k) of mv(k);carrying out a respectively Nb bits quantization to the real part and imaginary part of every element in V(k) by mvlin(k), and obtaining the quantized beamforming matrix Vq(k); Nb is positive integer; transmitting said quantization amplitude Mv(k) and said quantized beamforming matrix Vq(k).

Abstract: Techniques are provided herein to estimate parameters of a wireless communication channel. At each of a first plurality of antennas of a first wireless communication device, a transmission is received that is associated with each of one or more spatial streams transmitted via a second plurality of antennas of a second wireless communication device. The transmission comprises at least first and second training fields which are configured for channel estimation. Multidimensional channel information between the first plurality of antennas and the second plurality of antennas is computed from receive values in the first and second training fields for one more dimension above a number of the spatial streams transmitted by the second wireless communication device and up to a lesser of a number of the first plurality of antennas and a number of the second plurality of antennas.

Abstract: A method includes receiving a signal, which carries data in a sequence of symbols that are modulated in accordance with a pulse shape and transmitted in accordance with a timing clock. The received signal is filtered with a matched filter whose response is matched to the pulse shape of the symbols, to produce a filtered signal. The timing clock is initially recovered from the received signal prior to filtering with the matched filter. Upon meeting a predefined condition, a switch is made to recover the timing clock from the filtered signal after filtering with the matched filter. The symbols are demodulated using the recovered timing clock, so as to reconstruct the data.

Abstract: The present invention relates to a network node and a mobile node, and to related methods for wideband precoding. The methods comprise determining a phase compensation vector which is frequency dependent for the at least one predefined precoding weight vector in a precoding codebook for multi-antenna transmission. The methods further comprise determining a second precoding weight vector which is phase compensated by multiplying the at least one predefined precoding weight vector by the phase compensation vector.

Abstract: A radio signal receiving system for providing a signal to a transceiver includes a signal retrieving module and a signal processing module. The signal retrieving module retrieves a radio signal through one of a conducting wire in an electrical outlet, a conducting wire in a vehicular cigarette lighter, and a metallic vehicular casing. The radio signal receiving system operates without any conventional self-contained antenna and includes a radio signal receiving carrier which is either made from a conventional conducting wire or made of a metal to thereby enhance the efficiency of signal reception.

Abstract: Common-mode termination within communication systems. Termination is implemented with respect to two respective portions of a system: the intentional signaling within a communication system as well as any unintentional signaling which may be coupled into the system. Such unintentional signaling may be incurred in a variety of ways including via interference which may be generated by the system itself or by other devices or components external to the system. In addition, such unintentional signaling made be characterized as common-mode (CM) signaling, in that, it generally affects different respective portions of the system similarly or in the same manner. Various communication systems may include two or more devices implemented therein, that effectuate signaling via one or more communication links there between. Appropriate termination is made with respect to both the intentional and unintentional signaling portion of the system using any of a variety of impedance types (e.g.

Abstract: There is provided a solution for simultaneous reception of dual channel transmission. The solution is based on applying a first and a second oscillating signals, mixing and adding in order to separate the in-phase and quadrature components of first and second signals from a combined radio frequency signal received as input.

Abstract: Systems, methods, and other embodiments associated with a method for estimating a channel between a wireless transmitter and a wireless receiver are described. According to one embodiment, a method includes receiving a signal that includes non-pilot data that is not known to a receiver of the signal; determining an estimated channel for the signal based, at least in part, on the non-pilot data; processing the signal based, at least in part, on the estimated channel to produce an equalized signal; and decoding the equalized signal to produce output data.

Abstract: An apparatus and system for controlling traffic on an on-chip network. Embodiments of the apparatus comprise single-ended transmission circuitry and single-ended receiving circuitry on a first chip for coupling with a second chip, the transmission circuitry having impedance matching and lacking equalization, the receiving circuitry lacking equalization, the transmission circuitry and the receiving circuitry having statically configurable features and organized in clusters, wherein the clusters have the same physical layer circuitry design for different configurations of the configurable features, the configurable features including half-duplex mode and full-duplex mode, wherein the first chip and the second chip are on the same package, and wherein a plurality of conductive lines for coupling the first chip with the second chip are matched.

Abstract: A computational processor uses a binary signal, being a set of 1- or 0-valued elements of a same number as a number of elements in an input signal, to generate computational data whose elements are exclusive OR values between each element of the input signal and a corresponding element in the binary signal at a same position. The modulator 13 modulates the input signal and the computational data according to a primary modulation scheme, and generates primary-modulated signals. An IFFT calculator applies an inverse fast Fourier transformation to the primary-modulated signals to generate inverse transformation data. A transmitter generates a baseband signal based on generated inverse transformation data whose peak-to-average power ratio matches a standard, and generates and transmits a transmission signal from the baseband signal and data specifying computations conducted to generate the inverse transformation data that matches the standard.

Abstract: The invention relates to a receiver for a near-field chip-to-chip multichannel transmission system such as the capacitive or inductive links used for vertical signal transmission between the stacked chips of a system-in-package. A receiver for near-field chip-to-chip multichannel transmission providing 4 transmission channels for digital transmission between two monolithic integrated circuits comprises 4 coupling devices (211) (212) (213) (214), each of said coupling devices being a planar winding sensitive to magnetic field variations. A multiple-input-port and multiple-output-port amplifier (23) has 4 input ports, each of said input ports being connected to one and only one of said coupling devices (211) (212) (213) (214).

Abstract: Eye diagram scan circuit and associated method for a receiver circuit, including a level adjust circuit, a phase interpolator and a control module. The receiver circuit provides a first data signal and a primary phase data according to a received signal. The control module provides a phase offset data and a level offset data. The level adjust circuit adjusts a level of the received signal in respond to the level offset data; the phase interpolator triggers according to a sum of the phase offset data and the primary phase data, so a second data signal is provide in response to the level-adjusted received signal. The control module compares the first data signal and the second data signal, and accordingly provides an eye diagram scan result for the phase offset data and the level offset data.

Abstract: A Bluetooth receiver comprises a RF front end configured to receive a Bluetooth signal including a preamble and 34-bit pseudo-number (PN); a DC estimator communicatively coupled to the RF front end; and a frame synchronizer communicatively coupled to the DC estimator. The DC estimator is configured to perform DC offset estimation by determining an average value of samples of the preamble and the frame synchronizer is configured to use the 34-bit PN for frame synchronization.

Abstract: The present invention relates to a method for allowing a terminal to transmit CSI for downlink transmission from a base station through an uplink comprises the steps of: receiving a downlink signal through a downlink channel; generating CSI that contains one or more indicators among an RI, a PMI, and CQI for the downlink channel; and transmitting the CSI through an uplink channel, wherein the CSI can contain one or more pieces of information among a first type of CSI which is determined on the basis of a rank N that is determined by the terminal and a second type of CSI which is determined on the basis of a rank that is restricted by a reference value M.

Abstract: For channel estimation in a spectrally shaped wireless communication system, an initial frequency response estimate is obtained for a first set of P uniformly spaced subbands (1) based on pilot symbols received on a second set of subbands used for pilot transmission and (2) using extrapolation and/or interpolation, where P is a power of two. A channel impulse response estimate is obtained by performing a P-point IFFT on the initial frequency response estimate. A final frequency response estimate for N total subbands is derived by (1) setting low quality taps for the channel impulse response estimate to zero, (2) zero-padding the channel impulse response estimate to length N, and (3) performing an N-point FFT on the zero-padded channel impulse response estimate. The channel frequency/impulse response estimate may be filtered to obtain a higher quality channel estimate.

Abstract: Systems and methods of performing ASK or QAM modulation with uneven distance between symbols are provided. These are used to provide differing BER performances among bits sent from a transmitter to a receiver.

Abstract: An arrangement and method for digital frequency synthesis. The arrangement includes a device for phase quantization structured and arranged to operate based on a reference clock and a phase increment value, and a device for amplitude quantization structured and arranged to operate based on a reference clock and a phase increment value. The arrangement also includes a device for noise shaping of a phase arranged in the signal path after the device for phase quantization, a device for noise shaping of an amplitude arranged in a signal path after the device for amplitude quantization, and a phase to amplitude converter.

Abstract: A receiver in an OFDM based communication system is adapted to perform channel estimation using a received reference signal transmitted from at least one antenna The reference signal is substantially located into at least two OFDM symbols of a transmission time interval comprising of more than two OFDM symbols. A power level of said reference signal is divided into said non-consecutive OFDM symbols in said transmission time interval and adapted to use the reference signal located in a first OFDM symbol in succeeding transmission time intervals in addition to the reference symbols in a current transmission time interval and a preceding transmission time interval.