Abstract: The present disclosure provides a method of carrier phase error removal associated with an optical communication signal. The method includes estimating and removing a first phase angle associated with an information signal using coarse phase recovery, the information symbol being associated with a digital signal, the digital signal representing the optical communication signal; estimating a carrier frequency offset between a receiver light source and a transmitter light source by using the estimated first phase angle, the carrier frequency offset being associated with the information signal; removing carrier phase error associated with the carrier frequency offset; and estimating and removing a second phase angle associated with the information signal, the estimated second phase angle being based on the estimated first phase angle and the estimated carrier frequency offset.

Abstract: A method allows reconfigurable multi-element antennas to select the antenna configuration in MIMO, SIMO and MISO communication system. This selection scheme uses spatial correlation, channel reciprocal condition number, delay spread and average Signal to Noise Ratio (SNR) information to select the antenna radiation pattern at the receiver. Using this approach, it is possible to achieve capacity gains in a multi-element reconfigurable antenna system without modifying the data frame of a conventional wireless communication system. The capacity gain achievable with this configuration selection approach is calculated through numerical simulations using reconfigurable circular patch antennas at the receiver of a MIMO system that employs minimum mean square error receivers for channel estimation. Channel capacity and Bit Error Rate (BER) results show the improvement offered relative to a conventional antenna selection technique for reconfigurable MIMO systems.

Abstract: Digital spur reduction in which spurs are kept outside selected channels of interest. An integrated radiofrequency transceiver circuit has digital and analogue components, the circuit includes a radiofrequency signal receiver having a local oscillator signal generator configured to provide a local oscillator signal at a frequency fLO and a mixer configured to combine an input radiofrequency signal with the local oscillator signal to produce an intermediate frequency signal; and a clock signal generator configured to generate a digital clock signal at a frequency fDIG for operation of the digital components, where the local oscillator signal and/or a reference signal from which the local oscillator signal is derived are generated such that digital spurs lie outside a band selected by the receiver.

Abstract: Parallel/serial conversion is performed on an N (where N is a natural number)-bit first parallel data signal with a first converted clock acquired by multiplying a reference clock by N, and parallel/serial conversion is performed on an (N×K)-bit (where K is a natural number) second parallel data signal with a second converted clock acquired by multiplying the reference clock by N×K.

Abstract: Systems and methods for reducing the peak-to-average ratio (PAR) at the transmitter can reduce the dynamic range required in various analog components. PAR can be reduced by applying a time-domain compensation signal which reduces the magnitude of peaks in the time-domain signal prior to transmission where the time-domain compensation signals use tones that are reserved for the purpose of reducing the PAR. The reservation of these reserved tones for PAR can be implemented by altering the typical startup procedures in a digital subscriber line (xDSL) system. The use of the reserved tones to reduce the PAR can be implemented using a low complexity algorithm or using an adaptive technique.

Abstract: The present invention provides an adaptable codec for use in a communication system. The adaptable codec is capable of encoding a digital stream to be transmitted according to any one of a number of encoding schemes. A particular encoding scheme may be selected based on information received from a network entity that is separate from the communication system, a user associated with the communication system, a remote communication system with which communications are established, or a combination thereof. Once a particular encoding scheme is selected, an encoder will encode the digital stream to be transmitted, and a packet processor will create packets from the encoded digital stream. The selection of an encoding scheme will generally correspond to a desired quality of experience level.

Abstract: Disclosed are a method for generating a code sequence that can be used for acquisition of initial synchronization, cell detection, channel estimation, etc. in a mobile communication system, and a transmitter. A method for generating a code sequence in a transmitting side of a mobile communication system includes combining at least two code sequences with each other, and converting a code sequence generated by the combining step into a time domain signal.

Abstract: A method of delay spread compensation, suitable for use in a communication device a having plurality of receiver antennas, is disclosed. The method comprises receiving a plurality of signals, each via a respective antenna, wherein each signal comprises a signal component corresponding to a transmitted signal, and wherein each received signal experiences a respective channel impulse response having a corresponding delay spread; determining estimates of each of the channel impulse responses; calculating post-coding characteristics based on the estimates of the channel impulse responses; and post-coding the plurality of received signals using the post-coding characteristics to produce at least a first delay spread compensated signal. Corresponding computer program product, processing arrangement and communication device are also disclosed.

Abstract: A method for indicating a combination between a codeword and a layer in a MIMO communication system, a layer mapping method, and a data transmission method using the same are disclosed. A minimum number of codeword-layer mapping combinations from among all available combinations based on the numbers of all codewords and all layers are pre-defined in consideration of a ratio of a codeword to a layer, a reception performance of a receiver, and reduction of combinations, so that a data transmission method using the predefined combinations is implemented. If a specific one codeword is mapped to at least two layers, a diversity gain can be acquired.

Abstract: In an FSK receiver according to the present invention, a correction operation for a DC offset component is performed based on a maximum value and a minimum value of a demodulation signal. If a difference between the maximum and minimum values is less than a predetermined threshold value TH1, the correction operation is halted. Thus, the FSK receiver can rapidly perform an appropriate offset removal from a multi-level FSK signal.

Abstract: A method of generating a noisy receive signal for testing the performance of a mobile wireless communication device is described. A signal generator unit generates a transmit signal that frequency hops among a set of carrier frequency channels in a cyclic pattern having a time duration T. A wireless channel emulator unit generates a receive signal by modifying the transmit signal and also generates an interference signal by modifying the receive signal. The wireless channel emulator unit delays the interference signal relative to the receive signal by an integer multiple of the time duration T. The receive signal and the interference signal are combined by a combiner unit to generate the noisy receive signal.

Abstract: A broadband powerline communication system is disclosed which makes use of knowledge of the spectrum characteristics of a local radio environment in order to improve the performance of the system. A determination is made of the spectrum characteristics of a radio environment in the vicinity of the broadband powerline communication system that is transmitting data on modulated carrier frequencies. Certain ones of the carrier frequencies otherwise used by the broadband powerline communication system may be masked (i.e., not used) by all or part of the broadband powerline system in order to avoid interference based on the determination. The spectrum characteristics may be determined 1) in advance and used to compile a configuration database comprising frequency masking parameters; 2) by monitoring the local radio environment using the transmitter/receiver nodes of the system; or 3) based upon receipt of an indication from a conflicting user that the user is experiencing interference.

Abstract: The present invention provides a method and an apparatus for transmitting data using a codebook. The method includes: receiving current antenna configuration information of a transmitting end; obtaining a mask matrix corresponding to the current antenna configuration according to the current antenna configuration information; generating a codebook corresponding to the current antenna configuration according to a mother codebook and the mask matrix; selecting one codebook element from the codebook, and transmitting indication information corresponding to the codebook element to the transmitting end; and receiving data transmitted by the transmitting end. In the embodiments of the present invention, a mask matrix is obtained according to current antenna configuration information, and a codebook is generated according to the mask matrix and a mother codebook that is corresponding to the maximum number of antennas and the maximum number of layers that are fed back through channel state information.

Abstract: A method for a wireless communication system is provided. The method includes isolating a set of pilot signals, where the pilot signals are associated with multiple base stations or multiple sectors of a single base station. This includes nulling a subset of the pilot signals to mitigate co-channel interference and to perform channel estimation in accordance with at least one of the pilot signals.

Abstract: The present invention relates to a method of transmitting and a method of receiving signals and corresponding apparatus. One aspect of the present invention relates to an efficient L1 signaling method for an efficient transmitter and an efficient receiver using the efficient L1 signaling method for an efficient cable broadcasting.

Abstract: The receiver portion of a UWB wireless device is altered by replacing analog-to-digital circuitry with a simple energy detection circuit. In embodiments, the coding methodology of a transmitter is altered to support the simplified receiver configuration. For example, instead of coding the data to be sent in the phase of the UWB signal, the data is encoded in a binary fashion in discrete frequency subbands of the UWB signal. Although this may reduce the usable bandwidth of the channel, it also decreases the complexity and power consumption of UWB devices. In one or more embodiments, a UWB device is able to select a transmission mode (BPSK or Energy Coding) based on its environment. Moreover, in one or more embodiments, receiving devices may switch between coding modes based on the capabilities of a remote transmitter and/or a peer receiver.

Abstract: A method of transmitting a codebook index in a wireless communication system includes receiving a feedback index regarding an entity selected from a plurality of entities belonging to a feedback codebook, selecting a precoder from a precoding codebook using the feedback index, the precoding codebook comprising a plurality of precoders and transmitting a precoder index of the selected precoder. Flexibility can be given to codebook designs, and overhead due to the feedback of codebook indices can be reduced.

Abstract: A clock data recovery circuit includes: a demodulation filter that receives a transmission signal transmitted by two orthogonal carrier waves having I and Q phases and executes demodulation to obtain a demodulated wave having an phase and a demodulated wave having a Q phase from the transmission signal; a first determination circuit that determines whether an absolute value of one of the two demodulated waves is greater than an eye opening maximum value at an ideal clock phase of the transmission signal; a second determination circuit that determines whether the one demodulated wave is greater than zero; a third determination circuit that determines whether the other one of the two demodulated waves is greater than zero; and a phase comparison unit that detects whether a phase of a clock signal included in the transmission signal is leading a phase of a data signal included in the transmission signal, based on determination results obtained by the first to third determination circuits.

Abstract: Provided is an apparatus and method for analyzing identification (ID) signals by converting radio frequency (RF) signals which are transmitted with an ID signal added thereto by a transmitting part, e.g., a plurality of transmitters or repeaters, into signals of a desired band; creating ID signals that are identical to the ID signals added to the RF signals; calculating correlation values between the converted signals and the created ID signals based on partial correlation; and extracting channel profile of multi-path signals caused by a channel between the transmitting part and the ID signal analyzing apparatus from the correlation value. The technology of the present research is applied to broadcasting and communication.

Abstract: Various embodiments are directed to systems and methods for processing signals comprising a first component and a second component. A bandwidth of the first component may be centered at a center frequency. A bandwidth of the second component may be offset from the center frequency by an offset frequency such that at least a portion of the bandwidth of the second component overlaps a skirt of the first component. In various embodiments, a transmitter may split a single signal to generate the first and second components, shift the frequency of the second component, recombine and transmit the two components. Also, in various embodiments, a receiver may receive the signal and derive the first and second components by correcting for cross-interference.