Abstract: A technique for an equalizer filter with dynamically configurable code domain filter is described. The input to a transmitter chain is modified by an equalizer filter with dynamically configurable code domain filter, prior to being applied to the transmitter. The equalizer filter with dynamically configurable code domain filter modifies and smoothen the amplitude of the signal. The modified and smoothen signal has its peaks reduced which results in lower Crest Factor with negligible degradation of Error Vector Magnitude of individual codes. The input to the equalizer filter with dynamically configurable code domain filter could be a baseband, an intermediate frequency (IF) or radio frequency (RF) signal. When the signal is an IF or RF signals it needs to be down converted to baseband before applied to the equalizer filter.

Abstract: The present invention provides an equalizer processing module within a wireless terminal having an equalizer interface that receives an incoming baseband signal from a baseband processor operably coupled to the equalizer processing module and outputs soft decisions. A processor or advanced reduced instruction set computer (RISC) machine (ARM) couples to the equalizer interface while an equalizer accelerator module operably couples to the processor or ARM. Processing of the incoming baseband signal to produce soft decisions is performed by the combination of the processor and equalizer accelerator module. A sample capture buffer and an equalizer output buffer which may or may not be within the equalizer processing module allow data to be sampled and serves as the input and output for the equalizer processing module. This equalizer accelerator may specifically perform compute intensive operations such as Trellis computations for MAP equalization or MLSE equalization.

Abstract: The frame words of the embodiments are suitable for frame synchronization and/or channel estimation. By adding the autocorrelation and/or cross-correlation functions of frame words, double maximum values equal in magnitude and opposite polarity at zero and middle shifts are obtained. This property can be used to slot-by-slot, double-check frame synchronization timing, single frame synchronization and/or channel estimation and allows reduction of the synchronization search time. Further, the present invention allows a simpler construction of a correlator circuit for a receiver. A frame synchronization apparatus and method using an optimal pilot pattern is used in a wide band code division multiple Access (W-CDMA) next generation mobile communication system.

Abstract: An apparatus and method for estimating a frequency offset in an Orthogonal Frequency Division Multiplexing (OFDM) system are provided. Two time domain signals are generated from one received OFDM symbol through two observation windows with different delay times. The two time domain signals are compensated for a candidate frequency offset. A discrete Fourier transform process and a phase compensation process in a frequency domain are performed. A difference between two frequency domain signals compensated for a phase difference is computed with respect to each candidate frequency offset. For all candidate frequency offsets, difference values are compared with each other. A candidate frequency offset mapped to a minimum difference value is detected as an optimal frequency offset. The frequency offset can be more exactly estimated without consuming a bandwidth and increasing hardware complexity of a receiver.

Abstract: The present invention is a dramatically enhanced RF link for low-data-rate applications (1-100 bps), using one or more transmitters to communicate with one or more receivers, at dramatically enhanced ranges. The receiver of the present invention can rapidly search, detect, and lock in on narrow band signal transmissions, that may be present in a much larger frequency band and which may be changing frequency during the duration of the message. These receivers enable ultra-low noise floor detection of longer range, more highly attenuated, signal transmissions, by decreasing the receiver bandwidth.

Abstract: A low cost method and system for efficiently implementing channel estimation in a wireless communication system using any desired length of a fast Fourier transform (FFT) independent of burst type or signal structure. The hardware complexity required to perform the channel estimation to process a plurality of different burst types is reduced. Simple tail zero-padding is used when the length of FFT is extended to a desired length for more efficient computation.

Abstract: A method of demodulating a signal in a transmission system where the modulation includes several substantially orthogonal subcarriers, and the vector of the propagation channel H[n,k] is known or the received signal includes at least pilot symbols emitting reference data. The method includes at least one step of estimating the symbol a[n,k] emitted on the kth subcarrier of the nth symbol of the modulation using a recombination step weighting the various signals received after synchronization and demodulation x[n,k].

Abstract: Provided is a system and method for performing a ranging process in a communication system. If a Subscriber Station (SS) detects the insufficiency of UpLink (UL) resources for transmission of a Ranging Request (RNG_REQ) message during the ranging process, it transmits a UL resource allocation request message requesting additional allocation of the UL resources to a Base Station (BS) for additional transmission of the RNG_REQ message to cause the BS to additionally allocate the UL resources for the additional transmission of the RNG_REQ message.

Abstract: The frame words of the embodiments are suitable for frame synchronization and/or channel estimation. By adding the autocorrelation and/or cross-correlation functions of frame words, double maximum values equal in magnitude and opposite polarity at zero and middle shifts are obtained. This property can be used to slot-by-slot, double-check frame synchronization timing, single frame synchronization and/or channel estimation and allows reduction of the synchronization search time. Further, the present invention allows a simpler construction of a correlator circuit for a receiver. A frame synchronization apparatus and method using an optimal pilot pattern is used in a wide band code division multiple Access (W-CDMA) next generation mobile communication system.

Abstract: A telecommunication MIMO receiver implements soft bit metric calculation with direct matrix inversion MIMO detection. The receiver has a detector that detects data symbols in a received signal by determining distances between received signal points and constellation points; a scaler that scales the distances using a scaling factor; and a soft bit metric calculator that uses the scaled distances to calculate scaled soft bit metrics. The receiver can also have a decoder that decodes the soft bit metrics to determine data values in the received signals. Preferably, the receiver also has a quantizer that dynamically quantizes the soft bit metrics before decoding by the decoder.

Abstract: A MIMO wireless system includes a transmitter that has a transmitter having a parser that parses a bit stream into multiple spatial data streams and multiple interleavers corresponding to the multiple spatial data streams, where each interleaver interleaves the bits in the corresponding spatial data stream by performing multiple column rotation to increase diversity of the wireless system. The MIMO wireless system also includes a receiver that has deinterleavers that deinterleaves spatial bit streams transmitted by the transmitter.

Abstract: A method to synchronize impulse radio signal in a receiver based on a cross-correlation between an input signal and a template pulse train is described. The method comprises the steps of receiving a radio signal, performing a correlation between the acquired radio signal and a template pulse train, splitting the correlation into at least two elementary correlations over intervals of predefined length and separated by a predetermined time to obtain elementary correlation output, performing an elementary threshold check on each elementary correlation output, summing the elementary threshold check outputs to form a sum result.

Abstract: Provided is a distortion compensation apparatus which can correspond to the number of carriers adaptively. The apparatus includes a distortion compensation processing circuit multiplying an input signal by a distortion compensation coefficient; a distortion compensation coefficient storage storing the distortion compensation coefficient correspondingly to the input signal power; a distortion compensation coefficient calculator calculating an update value of the distortion compensation coefficient stored in the distortion compensation coefficient storage, based on the input signal and a feedback signal being feedbacked from the output side of a distortion device; a digital filter inputting the output of the distortion compensation processing circuit. Further is included a modifying unit, which modifies the passband of the digital filter so as to reduce a distortion compensation control bandwidth in the predistortion portion, in response to the reduction of the number of carriers in the input signal.

Abstract: The frame words of the embodiments are suitable for frame synchronization and/or channel estimation. By adding the autocorrelation and/or cross-correlation functions of frame words, double maximum values equal in magnitude and opposite polarity at zero and middle shifts are obtained. This property can be used to slot-by-slot, double-check frame synchronization timing, single frame synchronization and/or channel estimation and allows reduction of the synchronization search time. Further, the present invention allows a simpler construction of a correlator circuit for a receiver. A frame synchronization apparatus and method using an optimal pilot pattern is used in a wide band code division multiple Access (W-CDMA) next generation mobile communication system.

Abstract: A mixer for mixing a signal, present as a sequence of time-discrete values with a time interval between two time-discrete values defining a first sampling frequency from a current frequency to a target frequency, includes a first mixer implemented to convert the signal from the current frequency to an intermediate frequency to obtain an intermediate frequency signal based on the first sampling frequency, wherein a spectral interval between the intermediate frequency and the current frequency depends on the first sampling frequency. Further, the mixer includes means for converting the intermediate frequency signal into a converted intermediate frequency signal which is based on a second sampling frequency. Additionally, the mixer includes a second mixer which is implemented to convert the converted intermediate frequency signal from the intermediate frequency to the target frequency to obtain a target frequency signal which is based on the sampling frequency.

Abstract: There is provided a clock generator for generating a single-phase clock into which jitter has been injected, having a multi-phase clock generating section for generating a plurality of clock signals having an almost equal phase difference from each other and a jitter injecting section for injecting jitter into the respective clock signals.

Abstract: A method and apparatus are provided for frequency synchronization in an Orthogonal Frequency Division Multiplexing (OFDM) system, wherein the method includes the steps of transmitting OFDM symbols in such a manner that a data symbol size of a particular OFDM symbol in each frame is set to be smaller than a data symbol size of a typical OFDM symbol within the frame, receiving the OFDM symbols and calculating respectively, correlation coefficients of the particular OFDM symbol based on both a time interval of corresponding data symbols and a time interval of data symbols of the typical OFDM symbol, taking respectively phases of corresponding correlation coefficient calculated from the particular OFDM symbol and estimating a decimal part of a frequency offset, and determining an integer part of the frequency offset corresponding to the decimal part of the frequency offset, thereby estimating an entire frequency offset and acquiring the frequency synchronization.

Abstract: A method and a device for carrier-frequency synchronization of a vestigial-sideband-modulated received signal (rVSB(t)) with a carrier signal (ej(2?(fT+?f)t+??)), which is affected by a frequency offset and/or phase offset (?f, ??), estimates the frequency offset and/or phase offset (?f, ??) of the carrier signal (ej(2?(fT+?f)t+??)) by means of a maximum-likelihood estimation. For this purpose, the vestigial-sideband-modulated received signal (rVSB(t)) is converted into a modified vestigial-sideband-modulated received signal (xVSB?(t?)), which provides time-discrete complex rotating phasors (|xVSB?(t?)|·ej2??f·t?+??), in which only the time-discrete phases (2??ft?+??) are dependent upon the frequency offset and/or phase offset (?f, ??).

Abstract: In one embodiment, the present invention includes a method for receiving at a transceiver from a baseband processor digital control information that includes both event and schedule information, storing the digital control information in a storage of the transceiver, and operating the transceiver according to the event and schedule information.

Abstract: A method of reducing a phase error caused by a plurality of error sources in a signal in the form of a sequence of a plurality of digital partial signals associated with a number of subcarriers (k) of a carrier, the method including, for each partial signal: equalization of the partial signal (Y(i,k)), estimation of the phase error of the equalized partial signal (X(i,k)), and correction of the estimated phase error of the equalized partial signal. One embodiment provides the equalization with elimination of an accumulation of a phase error over the sequence of the partial signals. In addition the estimation includes detecting a plurality of predetermined pilot signals and determining a phase correction factor on the basis of the detected pilot signals, with at least one multiplication operation carried out solely by means of shift and adding operations. A corresponding apparatus is also described.