Abstract: It is an object of the present invention to provide a radio signal demodulating device in which fluctuation follow ability of transmission channel environment is improved. The radio signal demodulating device according to the present invention receives the amplitude of an information signal in which known pilot signals are multiplexed, as a radio signal modulated in proportion to the time change of frequency of a carrier wave The radio signal demodulating device according to the present invention includes a frequency converting unit, a signal combining unit, a first pilot signal extracting unit, a second pilot signal extracting unit, a first pilot orthogonal signal generating unit, a second pilot orthogonal signal generating unit, a first error signal generating unit, a first weight factor updating unit for calculating a weight factor to be used in the signal combining unit, by using a first pilot orthogonal signal and a first error signal obtained by the first error signal generating unit.

Abstract: A controller for advanced receivers configures a plurality of advanced receiver modules based on figures of merit computed on the input signal. The controller also selects the appropriate output signal based on figures of merit of either the input or the output signals. The controller decisions can also be made in a bursty manner, where only a subset of the decisions to be made are made at a given time, thereby limiting the processing load of the control processor.

Abstract: A method for rate-shaping media streams; the method includes: receiving multiple input media streams, transmission parameters, wired transmission limitations and wireless transmission limitations that represent a current status of a wireless medium; and rate-shaping at least one input media stream out of the multiple input media streams, in response to: (i) the transmission parameters, (ii) the wireless transmission limitations, and (iiii) input media stream parameters. A system for processing media streams; the system includes: a controller, adapted to determine rate-shaping parameters in response to: (i) the transmission parameters, (ii) the wireless transmission limitations, and (iii) input media stream parameters; and a rate-shaper, connected to the processor, adapted to receive multiple input media streams and perform rate-shaping according to the rate-shaping parameters.

Abstract: A preamble noise cancellation circuit according to an aspect of the invention may include: a coupler dividing an input signal; a preamble noise detection unit subtracting a predetermined reference preamble signal from a received preamble signal output from the coupler to detect preamble noise included in the received preamble signal; and a noise cancellation unit subtracting the preamble noise detected by the preamble noise detection unit from the received preamble signal output from the coupler.

Abstract: Techniques for deriving channel estimates with different channel estimation filters are described. In one scheme, a filter selection metric is determined for a signal to be recovered, a channel estimation filter is selected based on the filter selection metric, and a channel estimate is derived with the selected channel estimation filter. In another scheme, a first channel estimate is derived with a first channel estimation filter having a first filter response, a first signal is recovered with the first channel estimate, and interference due to the first signal is estimated and removed. A second channel estimate is derived with a second channel estimation filter having a second filter response that is different from the first filter response.

Abstract: A cell selection apparatus is used in the environment in which multiple communication systems coexists and at least one of the communication systems use guard intervals inserted in the transmission signal. The apparatus includes delay profile creation means (722) for creating a delay profile from a received radio signal and detecting amplitudes and timing of multipath arriving waves; comparison means (728) for comparing at least one delay quantity of the multipath arriving waves with a guard interval of a signal used in at least one of said multiple communication systems; and determination means (730) for determining a cell provided by one of the communication systems to which a mobile terminal is to be connected based on the comparison result.

Abstract: Provided are a beamforming receiving/transmitting function and a beamforming receiving/transmitting structure, which are optimized for a given basic system in order to provide advanced performance in consideration of a wireless mobile communication system through a ultra-high performance CDMA array antenna based on continuously orthogonal spreading codes and a pre-rake scheme for non-interference communication. Also, there is provided a chip-level/symbol-level beamforming receiving/transmitting apparatus based on a multiple-input multiple-output (MIMO) system on a forward/backward link in order to be applied to various advanced wireless mobile communication applications by improving the performance and capacity of a Code Division Multiple Access (CDMA) array antenna system based on continuously orthogonal spreading codes and a pre-rake scheme for non-interference communication, and a forward and backward link automatic beamforming method.

Abstract: A method of fighting interference in a frequency-hopping communication system is disclosed. The system has at least one main sensor and one or more auxiliary sensors. According to at least one embodiment, frequency-hopping signals are received. The frequency-hopping signals are arranged to include useful bands and one or more guard bands inserted between the useful bands, and a ratio of the useful bands to the guard bands being chosen according to a predetermined value of probability of interference interception. Signals of the inserted guard bands having a signal level greater than a predetermined threshold are selected. A set of spatial-filtering weightings are calculated according to a correlation matrix of noise plus jammers alone on the signals selected. Baseband signals of the received frequency-hopping signals are filtered by the set of the calculated spatial-filtering weightings.

Abstract: Methods and apparatus for performing finger de-spreading and MRC combining are provided. A large antenna buffer is used to buffer all the finger signals of the same user so that the receiver can do both de-spreading and MRC at the same time without buffering the de-spreading finger symbols. For each user, a reference time is introduced to align all the finger signals of the same user in the Antenna Buffer. The reference time delay is used to generate the PN codes for de-spreading, as well as to count the number of symbols in a PCG or a frame. Methods for antenna buffer arrangement, interpolating filter implementation, channel estimation and MRC for traffic data channels, timing for the user's finger signal de-spreading and MRC, long code and short code generation for de-spreading, new finger allocation and finger timing adjustment.

Abstract: A method and system are disclosed to detect a broad class of signals including Advanced Television Systems Committee (ATSC) digital television (DTV) and wireless microphone signals. This signal detection method performs in Gaussian noise, employing Higher Order Statistics (HOS). Signals are processed in time and frequency domains as well as by real and imaginary components. The spectrum sensing employed also supports Denial of Service (DoS) signal classification. The method can include parameters that may be tailored to adjust the probability of detection and false alarm.

Abstract: In a co-channel deployment of narrowband and multi-carrier technologies (e.g., a femtocell and a macrocell), a method provides cancelling of interference which treats the co-channel signals as desired signals and enhances each of them iteratively. At each iteration, each signal is demodulated and regenerated based on symbol decisions already made and a predetermined channel impulse response. To estimate the other (interfering) co-channel signal, the regenerated signal is subtracted from the aggregate signal. Simulations have shown that a method of the present invention can provide fundamental improvement in the performances of both interfering systems in as few as two iterations. The fundamental performance gain that can be obtained outweigh the required computational burden.

Abstract: A digital subscriber line (DSL) modem that has a canceller digital filter for cancelling crosstalk and RF interference in a received DSL signal is disclosed. The modem includes common-mode sense circuitry and also differential-mode sense circuitry. Samples of the common-mode signal are acquired during a “quiet” period of initialization of the DSL modem, and samples of the differential-mode signal are acquired during live transmission of a DSL signal. An estimate of an autocorrelation function is obtained from the common-mode samples, and a cross-correlation of the common-mode samples and differential-mode samples is also estimated. Digital filter coefficients are derived from these estimates, based on the assumption that the common-mode samples acquired during the “quiet” phase represent crosstalk and RF interference present during differential-mode communications.

Abstract: An apparatus and method for avoiding interference between a base station and a relay station when using full duplex relay in a multi-hop relay wireless communication system are provided. An operation of a mobile station includes measuring an strength of a receive signal from a base station and an strength of a receive signal from an relay station, calculating a receive signal strength ratio of base station to relay station by dividing the strength of the receive signal from the base station by the strength of the receive signal from the relay station, determining if interference occurs using the receive signal strength ratio, and transmitting a control message representing if interference occurs.

Abstract: The present invention discloses a signal processing device and a signal processing method. The signal processing device includes a plurality of receiving devices, a storage module, a weighting module, and a processing module. Each of the receiving devices is capable of receiving an original signal stream, thus the plurality of receiving devices can generate a set of signal streams. The storage module is used for storing a plurality set of signal streams generated by the plurality of receiving devices. The weighting module can generate plurality sets of rotated signal streams according to a reference phase and the plurality sets of signal streams, and further generate a set of weighting signal according to the rotated signal streams. And, the processing module can generate a set of weighting signal streams according to the set of weighting signal and the plurality set of signal streams.

Abstract: A noise power estimation apparatus is disclosed. The noise power estimation apparatus includes: a part for calculating correlation between a received signal and a pilot signal so as to obtain a received power of the pilot signal for each path; a part for removing a multipath interference component from the received power of the pilot signal by using a predetermined power ratio between the pilot signal and a data signal so as to obtain a corrected received power of the pilot signal; a part for estimating an estimated total power of the pilot signal and the data signal included in the received signal based on the corrected received power and the predetermined power ratio; and a part for subtracting the estimated total power from a total power of the received signal so as to obtain a noise power.

Abstract: A method for improving channel estimation in a wireless communication system is disclosed. A wireless signal that includes a plurality of multipath components is received. N channel estimates are then obtained, where N is any positive integer greater than one. Each channel estimate of the N channel estimates corresponds to a different multipath component of the plurality of multipath components. The effects of interference between the plurality of multipath components on the N channel estimates is then reduced.

Abstract: A multiple input multiple output (MIMO) communication system having a terminal and a base station. The terminal may calculate channel direction information and channel quality information in a zero-forcing mode based on expected different user interference. The terminal may also calculate channel direction information and channel quality information in a per user unitary rate control (PU2RC) mode by reusing the channel direction information and the channel quality information in the zero-forcing mode. The base station may design a preceding vector based on feedback information from the terminal.

Abstract: A multimode wireless communication device capable of communicating pursuant to first and second communication protocols, including a method wherein a determination is made (530) as to whether a harmonic generated during transmission in one protocol interferes with reception in another protocol, and wherein transmission is suspended while receiving only if a harmonic generated during transmission interferes with reception. In some embodiments, the transmitter is temporarily operated in compressed mode to enable the suspension.

Abstract: A rake receiver comprises a plurality of receive antennas and a processing system. Each receive antenna has a plurality of demodulation elements. The processing system is configured to assign a plurality of demodulation elements from a plurality of receive antennas to a multipath group, assign the multipath group to a multipath signal, and independently adjust a time delay value of each demodulation element in the multipath group to correspond to a local time delay of the multipath signal at the corresponding receive antenna.

Abstract: A method, a process and an audio system for embedding bit stream in a voice signal is disclosed. A voice/data interference signal is composed and supplied to the mixer of the voice signal and the data signal such that the resulting mixed signal effectively cancels the interference and allows the interference-free signal being transmitted to the audio signal receiver/decoder. The decoder may decode the data without interference errors. A method using profile shaping to mask the noise due to modulated carrier signal is also disclosed.

Abstract: This invention teaches to the details of an interference canceling receiver for canceling intra-cell and inter-cell interference in coded, multiple-access, spread spectrum transmissions that propagate through frequency selective communication channels to a multiplicity of receive antennas. The receiver is designed or adapted through the repeated use of symbol-estimate weighting, subtractive cancellation with a stabilizing step-size, and mixed-decision symbol estimates. Receiver embodiments may be designed, adapted, and implemented explicitly in software or programmed hardware, or implicitly in standard RAKE-based hardware either within the RAKE (i.e., at the finger level) or outside the RAKE (i.e., at the user or subchannel symbol level). Embodiments may be employed in user equipment on the forward link or in a base station on the reverse link. It may be adapted to general signal processing applications where a signal is to be extracted from interference.

Abstract: Provided are a channel estimation device and an equalization device capable of achieving high channel estimation accuracy with less amount of calculation processing. The equalization device includes: a channel estimation section including a ZF calculation/clipping processing section and correlation processing section; a weight calculation section; and an equalization filter. The ZF calculation/clipping processing section uses a signal obtained by converting a pilot code into a frequency domain to calculate a pilot reference signal according to a Zero Forcing (ZF) method and clips the gain of the calculated pilot reference signal to a predetermined value to generate a clipped pilot reference signal. The correlation processing section performs correlation between a pilot reception signal in the frequency domain and clipped pilot reference signal to estimate channel characteristics of the frequency domain.

Abstract: A system and method are provided for improving the performance of a beamforming antenna array in a wireless communications system. A predetermined number of spatial signatures are observed for a communications channel between a base station and a mobile terminal during a predetermined time period. One or more test spatial signatures are generated based on statistical analysis of the observed predetermined number of spatial signatures. A beamforming weight is derived based on the generated test spatial signatures for beamforming by an antenna subsystem of the base station.

Abstract: An iterative decoder circuit includes an N number of sub-decoders, N?1 of the sub-decoders each being responsive to a baseband signal from one of M number of signal processing circuits. Each of the N?1 number of sub-decoders includes, an inner delay responsive to a baseband signal provided by a corresponding signal processing circuit for generating an inner delayed signal, a modified decoder that receives the inner delayed signal and generates a set partition signal, some of which have less errors than previous set partition signals. An Nth inner delay is responsive to the baseband signal and provides an Nth inner delayed signal. An Nth modified decoder is responsive to the Nth inner delayed signal and to the set partition signal and provides an output signal, wherein the probability of error of the output signal is reduced by correcting errors in some of the set partition signals.

Abstract: In a communication system including a plurality of pairs of a transmitting device 2 and a receiving device 3, the transmission performance in the pairs is to be improved. The transmitting device 2-k transmits a transmission signal sk(t) to the receiving device 3-k a plurality of number of times. The receiving device 3-k updates the weight matrix Wk and the hopping pattern Pk used by the FIR filter which performs filtering on the transmission signal rk(t) at a predetermined time interval. The receiving device 3-k transmits the updated hopping pattern Pk to the transmitting device 2-k. The transmitting device 2-k receives the hopping pattern Pk to be used for subsequent spread spectrum.

Abstract: A narrowband interference (NBI) canceller is coupled to an A/D converter to receive an input signal and supply an NBI-canceled signal to an error correcting decoder. In the NBI canceller, a first arithmetic unit receives the input signal and a predicted-interference signal, and supplies a difference thereof as the interference-canceled signal. A slicer receives the interference-canceled signal and supplies a decision signal. A second arithmetic unit subtracts the decision signal from the input signal to generate a noise signal. A coarse frequency estimator receives the noise signal and analyzes the frequency spectrum to generate a coarse estimate of a fundamental frequency of the NBI. The coarse estimate is used by an adaptive narrowband interference predictor to generate the predicted-interference signal while adaptively tracking the narrowband interference. Use of the NBI canceller in a transceiver can eliminate link drop caused by operation of wireless devices that generate EMI in a cable.

Abstract: The present invention concerns a method for estimating, in a communication system, a level of interference plus noise affecting received signals representative of a set of received pilot symbols, characterized in that the method comprises the steps of: dividing the set of received pilot symbols by a corresponding set of pilot symbols, filtering the divided set of received pilot symbols by a filter the coefficients of which are determined from an eigenvector associated with one of the lowest eigenvalues of a channel fading correlation matrix representative of the correlation between the channel coefficients affecting the set of pilot symbols, averaging up the square absolute values of the symbols obtained at the output of the filter in order to estimate the level of interference plus noise affecting the received signals.

Abstract: The present invention provides a method of windowing signals in a communication system. The method includes accessing at least one first signal associated with at least one of a plurality of orthogonal frequencies and applying a window function to the at least one first signal to form at least one second signal. The at least one second signal remains substantially orthogonal to signals associated with the plurality of orthogonal frequencies.

Abstract: A communications device includes pre-processing circuitry for processing a received wideband complex signal including an undesired narrowband interference component therein, and for determining a frequency of the undesired narrowband interference component. A filter is downstream from the pre-processing circuitry and operable to generate a received wideband complex signal with at least one frequency notch therein to suppress the undesired narrowband interference component. The filter includes a finite impulse response (FIR) filter with L taps to generate N output values, with L>N. A Fast Fourier Transform (FFT) block is downstream from the FIR filter and has a length N so that filter transition regions occur between frequency bins of the FFT block. A notching block is downstream from the FFT block to generate the frequency notch. An Inverse Fast Fourier Transform (IFFT) block is downstream from the notching block and has the length N.

Abstract: Techniques for detecting and mitigating interference are described. A device (e.g., a cellular phone) senses interference levels and digitally reconstructs the expected interference in the received signal. The device may correlate the reconstructed interference with the received signal and determine interference in the received signal based on correlation results. The device may adjust the operation of one or more circuit blocks (e.g., a mixer, an LNA, etc.) in a receiver based on the detected interference in the received signal. Alternatively or additionally, the device may condition the digital interference to obtain conditioned reconstructed interference matching the interference in the received signal and may then subtract the conditioned interference from the received signal.

Abstract: A method of performing cell search includes receiving a primary synchronization signal (PSS) comprising a primary synchronization code (PSC), and receiving a secondary synchronization signal (SSS) comprising a first secondary synchronization code (SSC) and a second SSC. The first SSC and the second SSC are respectively scrambled by using a first scrambling code and a second scrambling code, and the first scrambling code and the second scrambling code are associated with the PSC. Detection performance on synchronization signals can be improved, and cell search can be performed more reliably.

Abstract: Two versions of the auto-covariance matrix of a received signal are obtained. One version is dependent upon the fraction of the power of a transmission site that goes into the wanted signals and a value is sought for this fraction that produces a good match between the two versions.

Abstract: A disclosed signal transmitting method includes the steps of a) categorizing plural digital signals, obtained by performing A/D conversion on plural analog signals consecutively arranged in a time direction, into plural signal groups in an order starting from lower bits of the plural digital signals, b) performing code spreading on the plural digital signals by using a different spread frequency for each signal group and using different spread codes for each bit, c) multiplexing the spread digital signals, and d) transmitting the multiplexed plural digital signals.

Abstract: In general, in one aspect, the disclosure describes a unified simplified maximum likelihood detector to be utilized with multiple input multiple output (MIMO) receivers to estimate transmitted signals. The unified detector includes a common framework capable of being utilized for multiple detection modes and multiple MIMO configurations.

Abstract: Interference in a wireless communication is minimized, or at least reduced, by scaling the symbols received from an interfering transmitter. Input samples from the interfering transmitter are isolated and decovered to generate received symbols. The gains of the received symbols are scaled to reduce the interference and the scaled symbols are covered to produce output samples that are spread to generate interference cancelled samples with reduced interference from the interfering transmitter. The function applied to scale the symbols may be linear or nonlinear.

Abstract: Multipath components of transmitted data symbols are received with individual delays and processed by a RAKE having a number of fingers. A delay profile indicating magnitudes for a first number of delay values is provided. Estimated magnitudes for a second number of delay values located between the first number of delay values are calculated by interpolation, and a combined delay profile is provided by combining the magnitudes for the first and second number of delay values. Delay values for peaks in the combined delay profile are determined, and a number of peak delay values (P1, P2, P) comprising the largest peak are selected from the combined delay profile. At least some of the selected peak delay values are provided to the RAKE and assigned to the fingers. This allows a reduction of current consumption and dye area, while still providing delay values with sufficient resolution for the RAKE.

Abstract: It is a theme of the present invention to provide a diversity receiving device capable of reducing a power consumption to the utmost extent while keeping a predetermined received quality without measurement of an electric field strength and a fading pitch. A decision about whether or not the diversity reception is executed is made by sensing a received quality. Also, a diversity gain is reduced by a predetermined value by controlling the diversity gain in the diversity reception, then a receiving operation of a predetermined branch or a branch whose received quality is low is stopped when the received quality at that time is in excess of a previously set value, and then a supply of power to all circuit or a partial circuit of the branch whose receiving operation is stopped is shut down. Accordingly, a power consumption can be reduced to the utmost extent while keeping a predetermined received quality.

Abstract: A method of processing positioning signal constituted by a superposition of individual signals generated by a plurality of emitters, in particular satellite emitters, comprising:—a first step of coarse acquisition of said individual signals, comprising correlation of the received positioning signal with locally generated replicas of said individual signals;—a step of identifying spurious correlation peaks induced by interferences; and—a step of estimating the code delays and the carrier frequency shifts of the acquired individual signals which are not affected by said interferences. According to preferred embodiments of the invention, the method can also comprise:—a refining step of determining more accurate estimates of said code delays and carrier frequency shifts; and—a step of interference cancellation. The method of the invention is particularly suitable to indoor positioning applications.

Abstract: Narrow-band interference in spread spectrum systems is eliminated by performing a frequency spectrum transform on N sampling points of the data to obtain N points of data; after M transforms, getting an energy accumulation of individual data to obtain N energy values; removing partial excessive large values from the N energy values, averaging the rest, then calculating the threshold value for interference determination based on the average value; identifying all points that have energy values exceeding the threshold value, and performing interference suppression for the data of corresponding points after frequency spectrum transform and finally outputting the data after frequency spectrum inverse transform.

Abstract: A method to equalize multiple-input multiple-output (MIMO) signals assigns a weight to the output of each receive chain in the MIMO system based on a first noise power value in each receive chain. A second noise power value can be computed using a difference between identical symbols from one or more weighted/un-weighted receive chain signals. Notably, the second noise power value includes thermal noise, phase noise, quantization noise, and distortion noise. The weighted outputs of the receive chains and the second noise power estimate may be used in an equalization calculation to recover the input signal.

Abstract: Reception signals received by first to fourth antennas 11 to 14 are sequentially selected one by one repeatedly in accordance with first to fourth switches 31 to 34 being controlled by first to fourth switch control circuits 41 to 44, respectively, so as to be inputted to a signal shaping section 60. The reception signals having been shaped by the signal shaping section 60 are sampled by a sample-and-hold section 71 and AD-converted by an AD converter 72 in accordance with a time at which the reception signals are sequentially selected. The resultant signals are converted into parallel signals by a serial-parallel conversion section 73. Thus, the parallel signals are obtained as the reception signals of the first to the fourth antennas 11 to 14.

Abstract: An IS-OFDM system for point-to-point wireless communications that suppresses narrow-band interference comprises an IS-OFDM transmitter and an IS-OFDM receiver, wherein a transmitted signal comprises a plurality of subcarriers, and further wherein each subcarrier contains more than one and potentially all symbols transmitted in a given frame. The IS-OFDM transmitted signal is at a data rate that is equal to the data rate of the input data stream via the use of PIS converters.

Abstract: Aspects of a method and system for a single antenna receiver system for W-CDMA are provided and may comprise computing channel estimates based on received multipath signals. Timing correction signals indicating a location of the received multipath signals may be generated and the received multipath signals may be combined based on the computed channel estimates and/or the generated timing reference signals. The multipath signals may be combined as a signal cluster. Circuitry may be provided that computes channel estimates based on at least one of a plurality of received multipath signals, and generates timing reference signals indicating a location of at least one of the plurality of received multipath signals. Circuitry may also be provided that combines at least a portion of the plurality of received multipath signals based on at least a portion of the computed channel estimates and/or the generated timing reference signals.

Abstract: A system includes a differential demodulation module that differentially demodulates modulated signals received from R antennas. A first summing module sums the differentially demodulated signals to generate a combined signal. A state detection module detects states of X symbols in the combined signal. A second summing module (i) receives Y preamble sequences each comprising X predetermined symbols and (ii) generates X sums for each of the Y preamble sequences by adding each of the states of the X symbols with corresponding states of the X predetermined symbols of each of Y preamble sequences. The states of the X predetermined symbols are generated by inverting states of derived symbols in derived preamble sequences, which are derived from the Y preamble sequences. Each of the Y preamble sequences is different from others of the Y preamble sequences. R, X, and Y are integers greater than 1.

Abstract: A receiver in a CDMA system comprises a front end processor that generates a combined signal per source. A symbol estimator processes the combined signal to produce symbol estimates. An S-Matrix Generation module refines these symbol estimates based on the subchannel symbol estimates. An interference canceller is configured for cancelling interference from at least one of the plurality of received signals for producing at least one interference-cancelled signal.

Abstract: The present invention relates to a method for estimating a propagation channel in the presence of transmit beam-forming within a receiver, accounting for the structure of two logical channels referred as to a common channel and a dedicated physical channel (CPICH, DPCH) and based on a common structure of corresponding propagation channels, said DPCH channel comprising two sub-channels (DPDCH, DPCCH), said propagation channels being modeled as a linear superposition of a finite number of discrete multipath components following an uncorrelated-scattering wide-sense stationary model, a multipath component being characterized by a time-varying multipath complex coefficient and a delay. Use: RAKE Receiver.

Abstract: An inter-carrier interface removal device can improve estimation accuracy of inter-carrier interference caused by Doppler shift in a received multi-carrier signal moving at a high speed, and a reception characteristic of the multi-carrier signal after removing the inter-carrier interference.

Abstract: A method and system for detecting the presence of narrowband transmitters utilizing frequencies also utilized by wider band communication systems. In some embodiments an ultrawideband transceiver detects signals at specific frequencies within a spectrum of frequencies, and analyzes the signals to determine if the signals indicate transmissions by a narrowband transmitter in a narrowband communication system. In further embodiments transmission circuitry reduces signal components at frequencies occupied by the narrowband transmitters.

Abstract: Techniques for detecting and suppressing jammers are described. A receiver may perform post-FFT jammer detection and pre-FFT jammer suppression. The receiver may transform an input signal to obtain a frequency-domain signal and may detect for jammers in the input signal based on the frequency-domain signal. The receiver may determine powers of a plurality of carriers based on the frequency-domain signal and may detect for jammers based on peaks in the powers of these carriers. The receiver may filter the input signal (e.g., with a notch filter) to suppress the detected jammers. Alternatively or additionally, the receiver may perform post-FFT jammer detection and post-FFT jammer suppression. The receiver may determine whether jammer is present on each carrier based on data power and channel power for that carrier. The receiver may modify (e.g., zero out or reduce) the frequency-domain signal on carriers with detected jammers.

Abstract: Rake receivers in code division multiple access (CDMA) telecommunication comprise fingers (1,2,3) with each finger processing signal components for a particular transmission path to be able to better synchronize with a RF signal received via different paths, and a combiner (4) for combining the results originating from said fingers, and a compensator in the form of a controlled oscillator in a feedback loop. By locating a finger compensator (20-25) in a finger, said finger can handle complex situations, like Doppler shifts under high-speed conditions. Preferably, most or all fingers each comprise such a finger compensator, in which case said feedback loop can be avoided. Such a finger compensator can be hardware, software or a mixture of both when comprising a filter (21) plus an amplitude normalizer (22) between two arithmetical modules (20,25) for multiplying an input symbol signal with a conjugated previous input symbol signal and an output symbol signal with a previous output symbol signal.