Abstract: A wireless network may comprise a plurality of base stations and a plurality of access points, such as femtocells, which may be installed in homes and/or offices, as deemed necessary to provide improved signal quality and increased data throughput while off-loading capacity from one or more near-by base stations. A user device may be configured to detect proximity to an access point and establish communications preferentially with the access point while refraining from communicating with a base station even though the user device is within a service region of the base station and can communicate with that base station.

Abstract: The present invention relates to a method includes: implementing, by the board in the BBU1, frequency synchronization between a system clock of the board in the BBU1 and a system clock of the board in the BBU0 by using a synchronous Ethernet clock that is output by the board in the BBU0; and implementing, by the board in the BBU1, time synchronization between the system clock of the board in the BBU1 and the system clock of the board in the BBU0 by using an IEEE1588 clock that is output by the board in the BBU0. The present invention can enable the multimode base station to support more standards.

Abstract: A signal processing method and apparatus. According to the signal processing method, phase change processing can be performed on to-be-sent data signals according to a phase status of a data synchronization signal and phase statuses of the to-be-sent data signals, so that phase differences between a majority of to-be-sent data signals in the processed to-be-sent data signals and the data synchronization signal meet a certain condition, thereby reducing a volume of coupling crosstalk, generated by the to-be-sent data signals, on the data synchronization signal and further reducing impact of simultaneously switching noise (SSN) on a system.

Abstract: A tuner receives a received signal using one of a plurality of transmission formats that use at least one of either a first frequency or a second frequency band. A determination unit determines the transmission format being used in the received signal from among the plurality of transmission formats. In the determination unit, a pattern matching unit stores in advance a plurality of patterns respectively expressing a received waveform of a preamble in each of the plurality of transmission formats, conducts a pattern matching process between the received signal and the each of the plurality of patterns, and obtains a correlation value. A transmission mode determination unit determines the transmission format being used in the received signal on the basis of the correlation value.

Abstract: Systems and methods are presented for controlling the peak-to-average-power of a baseband orthogonal-frequency-domain multiplexing (OFDM) signal by designating a subset of the available subcarriers as information-bearing data-subcarriers, and loading remaining subcarriers by symbols that are a function of the symbols loading the data-subcarriers. At the receiver, the data-dependent subcarriers are optionally combined with data-subcarriers to increase error protection.

Abstract: The presence of an RF signal in an expected location emanating from a mobile device within the expected location is detected by first antenna positioned in the expected location. False alarm discrimination is achieved by the square ratio of the operator's cellphone signal close to the antenna(s) versus the blocked external signals from much greater distance. A comparator compares the RF signal emanating from the mobile device in the expected location with a threshold signal and determines whether the mobile device is operating, and, if so, an alarm responsive to the comparator is triggered.

Abstract: Embodiments of the present invention disclose a beam codebook generation method, includes: calculating a first array response factor of a reference beam according to the number of actually generated beam signal channels, and calculating a second array response factor of the reference beam according to the preset number of target beam signal channels; performing radiated power normalization processing on the first array response factor to obtain a first radiation factor of the reference beam, and performing radiated power normalization processing on the second array response factor to obtain a second radiation factor of the reference beam; performing normalization processing on the first radiation factor and second radiation factor to obtain a beam codebook of the reference beam; and performing rotation processing on the obtained beam codebook of the reference beam to obtain a beam codebook of one or more other beams except the reference beam in the target beams.

Abstract: A novel framing method for a variable net bit rate digital communications system that utilizes a set of different QAM constellations and punctured trellis code combinations, each combination designated as a mode. This frame structure has a variable integral number of QAM symbols per frame depending on the selected mode, but the number of bytes and Reed-Solomon packets per frame is constant. This is achieved even though the number of data bits per QAM symbol for some modes is fractional. Also the number of trellis coder puncture pattern cycles per frame is an integer for all modes. This arrangement simplifies the synchronization of receiver processing blocks such as the Viterbi decoder, de-randomizer, byte de-interleaver, and Reed-Solomon decoder.

Abstract: Rather than using separate sample rate offset and phase offset estimation algorithms for coarse timing synchronization and fine timing synchronization of a receiver timing, respectively, one phase error algorithm can be used for both the coarse and fine timing synchronization. In order to perform coarse timing synchronization the phase error indications sampled over a sampling period are used to form an error vector, and a Fourier transform can then be applied to the error vector. An analysis of the Fourier transform of the error vector can be used to determine a frequency component identifying an offset between the receiver frequency and the signal frequency. The frequency of the receiver timing can then be adjusted in accordance with the identified offset, thereby performing the coarse timing synchronization. Once the coarse timing synchronization has been applied, the same phase error algorithm may be used, without the Fourier transform, to implement the fine timing synchronization.

Abstract: A receiver and a method for providing block synchronization of symbols and integral frequency offset correction of subcarriers are provided. Samples of a received signal are transformed into the frequency domain. Subcarrier extraction is performed to extract selected subcarriers. The extracted subcarriers are differentially demodulated using subcarriers from the previous symbol and coherently combined with reference subcarrier values to obtain sample vectors. The sample vectors are obtained over a number of symbols preferably equal to the number symbols in a block. Cyclic correlation is performed on those sample vectors relative to a known synchronization (sync) pattern. A maximum magnitude search is performed over sample vectors obtained from the cyclic correlation to determine an integral frequency offset and a block boundary of the received signal. The integral frequency offset and the block boundary can be used to tune and synchronize the receiver for proper reception of the received signal.

Abstract: Disclosed herein are an apparatus and a method of estimating a channel in consideration of a residual synchronization offset. The apparatus of estimating a channel in consideration of a residual synchronization offset includes: a channel estimating unit estimating the channel using pilots scattered over a plurality of OFDM symbols and calculating a first channel estimated value as the estimation result, in the case in which an OFDM symbol estimating the channel and an OFDM symbol compensating for the channel are different from each other; and a phase reflecting unit calculating a phase generated by the residual synchronization offset in proportion to a difference between a channel estimation time and a channel compensation time, reflecting the calculated phase in the first channel estimated value, and calculating a second channel estimated value as the reflection result.

Abstract: In one embodiment, the method includes determining, at an access node, a precoder matrix for precoding transmission from the access node to a plurality of downstream devices over a plurality of lines. The plurality of lines include high power lines and low power lines. The high power lines are in active communication and transmit more symbols per frame than the low power lines. The method further includes precoding a signal vector using the precoder matrix regardless of the symbols the signal vector is sending over the low power lines. Here, the determining determines the precoder matrix such that the precoding does not mitigate the cross-talk effect the high power lines have on the low power lines. The method also includes transmitting over the plurality of lines based on the precoded signal vector.

Abstract: Methods and systems are provided for loop-through for multi-chip communication systems. Receiver circuitry, that is operable to receive one or more input feeds, may comprise a plurality of chips, each of which may be configurable to generate a corresponding output comprising one or more feed elements (e.g., channels) extracted from the input feed(s). However, only a first chip may be operable to handle reception and/or initial processing of the one or more input feeds, with each one of the remaining chips processing a loop-through feed generated by the first chip, in order to generate the corresponding output of that chip. The first chip generates the loop-through feed based on the one or more input feeds, such as after the initial processing thereof in the first chip. Generating the loop-through feed may comprise applying channelization (e.g., separately for each remaining chip), switching based processing, and/or interfacing based processing.

Abstract: The invention refers to generating a digital signal from an analog signal, wherein the analog signal is amplified according to a gain control value before being converted to a digital value by means of an analog-to-digital converter, wherein a DC offset value of the analog signal is determined, and the gain control value is generated as a function of the dynamic range of the analog-to-digital converter and the DC offset value. The invention further refers to a corresponding circuit and a computer program.

Abstract: Efficient methods and apparatus for tracking decision-feedback equaliser (DFE) coefficients are described. In an embodiment, updated coefficients for a feed-forward equaliser (FFE) are generated using conventional methods and then these are used, along with an averaged updated value of channel impulse response (CIR) estimate to generate updated DFE coefficients. In an embodiment, the updated DFE coefficients are generated by multiplying the updated CIR estimate (in the frequency domain) and the updated FFE coefficients (also in the frequency domain). The resultant updated DFE coefficients in the frequency domain may then be converted into the time domain before outputting to the DFE.

Abstract: A method of predistorting an input signal (902) for an amplifier is disclosed (FIG. 9). The method includes predistorting the input signal with a first set of parameters (FDPD) and a second set of parameters (CDPD) at a first time (904). The first set of parameters is updated at a second time (914). The second set of parameters is updated separately from the first set of parameters at a third time (920).

Abstract: A wireless communication device includes a BBIC for performing baseband signal processing, an RFIC for performing radio-frequency signal processing, and a quartz resonator. The RFIC has a storage unit which stores an adjustment value for adjustment of a clock frequency that is based on an oscillation frequency of the quartz resonator, and outputs the adjustment value when its resetting active state is canceled; a frequency adjusting unit for adjusting the clock frequency according to the adjustment value; and an RF signal processing unit which operates based on the clock signal and performs the radio-frequency signal processing.

Abstract: A communications receiver includes a noise analyzer to characterize the composition of the interference and/or distortion impressed onto a transmitted communications signal in the presence of one or more time-varying conditions. The noise analyzer may provide a selection signal indicating the composition of the interference and/or distortion impressed onto a transmitted communications signal in the presence of one or more time-varying conditions to be used by the communications receiver. In an exemplary embodiment, the communications receiver selects at least one set of filter coefficients to compensate for the interference and/or distortion impressed onto a transmitted communications signal in the presence of a particular time-varying interference and/or distortion condition.

Abstract: Techniques are presented herein to achieve reduced array gain associated with a transmission made from multiple antennas of a wireless communication device. In accordance with one technique, a wireless communication device is provided having a plurality of transmitters each configured to transmit via a corresponding one of a plurality of antennas. Subcarriers of at least one transmit signal to be weighted across the plurality of transmitters are allocated power so that for each subcarrier, only one transmitter is allocated a maximum power.

Abstract: A method includes, in a receiver that includes an uncompensated crystal oscillator, receiving signals from a transmitter by activating the receiver periodically at intervals corresponding to a specified wake-up time period. In response to detecting at the receiver that the specified wake-up time period is insufficient for maintaining synchronization between the receiver and the transmitter using the uncompensated crystal oscillator, an actual wake-up time period, smaller than the specified wake-up time period, is selected. The receiver is activated periodically according to the selected actual wake-up time period.