Abstract: The present invention provides a reception apparatus and reception method that reduce the amount of operation processing, reduce the processing delay and allow high signal separation performance. The reception method of the present invention is characterized by receiving signals including a plurality of codewords transmitted by a plurality of streams and performing maximum likelihood detection-based signal separation in the same codeword in the received signals while performing continuous interference canceller-based signal separation between different codewords.

Abstract: A method for supplying at least one bus user via a control unit, in which data are transmitted to at least one bus user during at least one phase for data transmission and power is transmitted during at least one phase for power transmission, the at least one phase for data transmission and the at least one phase for power transmission being provided alternately, and the lengths of the phases for data transmission and/or the lengths of the phases for power transmission being set variably.

Abstract: A method and apparatus for increasing, at a transmitter, a payload size of a communication channel having orthogonal groups, the method referencing a base orthogonal sequence set comprising orthogonal sequences that are mutually orthogonal, the orthogonal sequence set having subsets that are sub-block orthogonal with a length of four; and selecting a spreading sequence set from a plurality of spreading sequence sets, each of the plurality of spreading sequence sets comprising an orthogonal sequence set subset combined with an imaginary orthogonal sequence set subset, wherein the selecting increases payload size.

Abstract: The present invention relates to a method and arrangement for receiving an OFDM signal and forwarding the received OFDM signal comprising OFDM symbols of a wireless OFDM communication network. The wireless OFDM communication network includes self-interference cancelling functionality and each received OFDM symbol to be forwarded is prefixed with a cyclic prefix (CP) which is a copy of the last part of the OFDM symbol. In the method a delay for delaying an interference generating feedback signal is determined such that an OFDM symbol of the interference generating feedback signal overlaps within a margin of a length of the CP with an OFDM symbol of the received OFDM signal, and interference generating feedback signal is delayed with the determined delay. Furthermore may the duration of the impulse be shortened as well.

Abstract: In one aspect, the present invention provides for blindly detecting the presence of one or more secondary pilot signals that are not being used to serve a communication apparatus, such as a User Equipment (UE). Among its several advantages, the approach to blind detection taught herein provides robust detection performance, yet it requires relatively few receiver resources. The contemplated apparatus, in at least one example embodiment, uses its blind detection of secondary pilot signal(s) to trigger suppression of secondary pilot interference, for improved reception performance. In a particular, non-limiting example, the apparatus operates in an HSDPA-MIMO network in a non-MIMO mode and blindly detects secondary pilot signal energy associated with the supporting network providing MIMO service to nearby equipment.

Abstract: The invention relates to a method performed in a user equipment for estimating channel quality. The user equipment is adapted to operate in a multiple input multiple output (MIMO) mode in a communication system comprising a base station node supporting MIMO and serving the user equipment. The method comprises: receiving, from the base station node, a reference signal; performing joint demodulation of the reference signal, thereby obtaining soft values; and generating the channel quality using the soft values. The invention also relates to a user equipment, computer programs and computer program products.

Abstract: A radio receiver (100) comprises an analogue to digital converter (30) for generating a data word representative of a received radio signal and a gain control stage (40) comprising a first register (42) for storing the data word. The gain control stage (40) is adapted to control the numerical value of the data word by controlling the position of the data word in the first register (42).

Abstract: A communication system includes a transmitting unit with a peak to average power (PAPR) reduction section. The PAPR reduction section modifies the PAPR reduction it effects in a communication signal in accordance with two different error vector magnitude (EVM) constraints for each channel type, where a channel type is a distinct combination of a modulation order and a coding rate. The EVM constraint followed for each subcarrier in an OFDM or OFDMA application is selected in response to whether the subcarrier conveys voice or non-voice data. The PAPR reduction section may include a scaling filter. The scaling filter is efficiently defined through the use of a predetermined sinc function and a first stage scale factor that is calculated in response to a weighted average of excursion signal subcarrier gains, where the weighting follows the distribution of channel types through the subcarriers.

Abstract: A transmitter includes a layer mapper and a precoder. The layer mapper is configured to map 2 codewords to 3 layers to output a mapped set of 3 symbols. A first codeword is mapped into one layer, and a second codeword is mapped into two layers. The precoder is configured to precode the mapped set of 3 symbols using a precoding matrix that distributes the mapped set of 3 symbols across 4 antenna ports so that each codeword is distributed across 2 antenna ports.

Abstract: A transmission apparatus, a signal sending apparatus, and a signal receiving apparatus, and a transmission method, a signal sending method, and a signal receiving method capable of solving a problem of metastability and suppressing a delay of a signal when sending and receiving apparatuses having different operation clock frequencies send/receive the signal representative of control information, for example. Included are a sending part that operates in synchronization with a first clock having a first period to output a transmission signal having a signal level that is inverted in response to an input of a first pulse signal corresponding to the first period and a receiving part that operates in synchronization with a second clock having a second period to output a second pulse signal corresponding to the second period in response to inversion of a signal level of the transmission signal.

Abstract: Disclosed herein is a signal processing apparatus including: a frequency multiplier configured to carry out an N-times frequency multiplication process on a modulated signal obtained as a result of an N phase shift keying modulation process in order to generate a multiplied frequency signal; and an oscillator configured to oscillate the multiplied frequency signal as an injected signal in order to generate a signal obtained by carrying out a by-N frequency division process on the multiplied frequency signal to serve as a reproduced carrier which is a carrier reproduced from the modulated signal.

Abstract: Transmitting beamforming can steer a transmitting signal to reduce the interference between spaces of a MIMO system and achieves constructive combination at the receiver. One method of steering matrix calculation includes using singular value decomposition (SVD). Notably, the singular values of SVD, which represent the stream strengths in a MIMO system, are in descending order. In equal modulation, signal strength degradation makes the receive EVM of the latest stream poor and increases the probability of packet error. MMSE can be used to weight the steering vectors of the steering matrix calculated in SVD. This weighting of the singular values can balance the SNR of the streams, thereby improving packet error rate.

Abstract: A signal source synchronization circuit includes: a first TDC circuit that measures a first path delay time which is a time difference between an input time of a trigger signal to a first input terminal and an input time of the trigger signal to a second input terminal; and a second TDC circuit that measures a second path delay time which is a time difference between an input time of the trigger signal to a first input terminal and an input time of the trigger signal to a second input terminal, wherein a first phase shifter adjustment circuit sets a phase adjustment amount corresponding to the first path delay time in a first phase shifter, and a second phase shifter adjustment circuit sets a phase adjustment amount corresponding to the second path delay time in a second phase shifter.

Abstract: A multiple-antenna receiver can enable and disable receive radio frequency front-end and analog front-end circuits of specific antenna receiving routes according to a predetermined scheme during the receive data phase. The predetermined scheme calculates signal quality indices of the receiving route antennas according to a preamble sequence, and derives the modulation and coding scheme and the number of spatial streams via the information provided by a header sequence. Indications of the signal quality indices are compared with threshold values to determine which receiving routes are to be turned on and which receiving routes are to be turned off.

Abstract: A communication system is disclosed that allows high data-rate transmission of data between components. N-bit parallel data is transmitted in K-frequency separated channels on the transmission medium so as to fully take advantage of the overall bandwidth of the transmission medium. As a result, a very high data-rate transmission can be accomplished with low data-bit transmission on individual channels. A transmitter system and a receiver system are described for the communication system.

Abstract: A method of wireless data transmission includes a base station having six antennas and at least one user equipment. The base station forms at least one layer of data stream including modulated symbols, precodes the at least one layer of data stream via multiplication with consecutive first and second precoding matrices and transmit the precoded data stream to the at least one user equipment via the six antennas. The first precoding matrix W1 is a block diagonal matrix formed by two identical 3 by Nb matrices, where Nb is the number of distinct Discrete Fourier Transform vectors. The second precoding matrix W2 introduces a phase shift between the two 3 by Nb matrices and selects a column subset from the first precoding matrix.

Abstract: A transmitter for transmitting data symbols using an orthogonal frequency division multiplexing (OFDM) scheme, the transmitter comprising: a modulator for generating a plurality of mutually orthogonal sub-carriers, each of the plurality of sub-carriers being modulated with a stream of data symbols to be transmitted; an amplifier for amplifying a signal containing the plurality of modulated sub-carriers for transmission of the signal; and a symbol processor for processing the data symbols of the plurality of sub-carriers, the symbol processor being configured to compute a plurality of EVM values for each data symbol to be transmitted, each of the plurality of EVM values being computed based on a different one of a plurality of candidate back-off values for the amplifier, and to select one of the plurality of candidate back-off values to apply to the transmitter for the data symbol based on the computed EVM values.

Abstract: Exemplary embodiments of the present invention relate to a low-power highly-accurate passive multiphase clock generation scheme by using polyphase filters. An exemplary embodiment of the present invention may be low power phase-rotator-based 25 GB/s CDR architecture in case that half-rate reference clock is provided. It may be suitable for multi-lane scheme and incorporate phase interpolator with improved phase accuracy to make Nyquist-sampling clock phase. To improve the phase accuracy, poly phase filter may be used for converting 4-phase to 8-phase and interpolate adjacent 45 degree different phases. The linearity of phase rotator may be improved by proposed harmonic rejection poly phase filter (HRPPF) using the characteristic of notch filter response.

Abstract: A method and apparatus provide hybrid automatic repeat request (HARQ) feedback corresponding to the status of multiple downlink carriers, with or without MIMO being configured. Here, for at least some configurations, with respect to the selection of HARQ feedback symbols, the downlink carriers are grouped into groups of one or two carriers such that HARQ feedback symbol code books that were previously implemented in conventional HSDPA or DC-HSDPA systems may be utilized. That is, after encoding a data stream, HARQ feedback symbols selected from a plurality of code books configured for groups of one or two of the downlink carriers are utilized to modulate an uplink channel. The modulation or channelization may be accomplished with dual channelization codes or a single channelization code with a reduced spreading factor to insert two symbols into a single time slot.

Abstract: A signal transition detection circuit is provided. The signal transition detection circuit comprises a counter module, a DAC, a comparator and a digital sampling module. The counter module generates a digital step signal. The DAC converts the digital step signal into an analog input signal and transmits it to an under-test circuit such that the under-test circuit generates an output signal transiting from a first stable level to a second stable level, wherein a transition section is located between the first and the second stable level. The comparator receives and compares the output signal with a default value to generate a normalized output signal. The digital sampling module samples the normalized output signal to retrieve impulses such that when the number of the impulses is accumulated to be larger than a reference value, a corresponding step of the digital step signal is determined to be a transition point.