Abstract: The teachings presented herein improve the processing of individual signals of interest included in a received composite signal by computing combining weights and/or signal quality estimates for each signal of interest, e.g., for linear equalization, based on either shared or non-shared correlation estimates. As a non-limiting advantage, the use of shared correlation estimates reduces computational loading as compared to the processing load that would be needed for computing non-shared correlation estimates for all signals of interest. As a further non-limiting advantage, the conditional use of shared and non-shared correlation estimates provides for the use of non-shared correlation estimates where signal characteristic(s) of one or more of the signals of interest warrant such usage, e.g., for one or more high-rate signals of interest.

Abstract: Techniques, apparatuses and systems for providing communications based on time reversal of a channel impulse response of a pulse in a transmission channel between a transmitter and a receiver to enhance reception and detection of a pulse at the receiver against various effects that can adversely affect and complicate the reception and detection of the pulse at the receiver.

Abstract: A code converting apparatus is designed to estimate the incoming time and the like of a signal modulated by a spreading sequence composed of m elements in a set A having n kinds of symbols as elements accurately. A symbol sequence memory section 102 stores a converted sequence of symbols obtained by concatenating consecutive 2d symbols at the center of each sequence pattern pi composed of 4d elements in the set A. The converted sequence of symbols is structured so that d symbol immediately preceding the 2d symbols and d symbol immediately following the 2d symbols are identical to d symbol immediately preceding corresponding 2d symbols and d symbol immediately following the corresponding 2d symbols of a corresponding sequence pattern. A symbol sequence specifying section 103 specifies a matching sequence pattern for every consecutive 2d symbols in a symbol sequence obtained by assigning a symbol to the signal in a coding cycle of the spreading sequence.

Abstract: Direct detection of wireless interferers in a communication device for multiple modulation types. One or more radios implemented within a communication device is/are operative to receive and process wireless communications. A wireless communication signal is processed to extract symbols there from. Various symbols groups are processed in accordance with correlation processing to identify potential interferers (e.g., other communication devices using common portions of frequency spectra). Alternatively, matched filter processing (e.g., using a Barker matched filter in some embodiments) operates on the various symbol groups to identify some potential interferers. Various combinations of correlation processing and matched filter processing may be employed in other instances (e.g., using any of a desired means of comparison, combining, etc.) in considering interferers identified in accordance with each of these two means.

Abstract: To suppress effects produced on other terminals as much as possible, while obtaining the advantage of soft-combining. A multicarrier receiving apparatus that receives a packet comprised of at least a propagation path estimation symbol and a scrambled information symbol to demodulate, and has propagation path estimating sections 3-a and 3-b that respectively estimate propagation paths of radio signals transmitted from a plurality of transmission antennas, scramble multiplying sections 5-a and 5-b that respectively perform the same scrambling on propagation path estimation values output from the propagation path estimating sections 3-a and 3-b as scrambling provided in the information symbol on the transmission antennas sides, an adding section 3-c that adds scrambled propagation path estimation values, and a propagation path compensating section 7 that performs propagation path compensation of the information symbol included in the received packet using a signal output from the adding section 3-c.

Abstract: A method of wireless communication in a lossy environment entails generating a direct sequence spread spectrum (DSSS) code string that includes a pseudo-noise (PN) sequence followed by instances of shifted PN sequences, where the shifted PN sequences are produced in response to the content of the message. The PN sequence includes a plurality of chips arranged in a first order, and each of the shifted PN sequences includes the plurality of chips arranged in another order. A beacon signal modulated by the DSSS code string is transmitted from a transceiver and received at a receiver within the communication system. Correlation peaks are formed at the receiver, where each correlation peak is associated with one of the PN sequences or one of the shifted PN sequences. Shift values are determined from the correlation peaks and the shift values are decoded to produce the message at the receiver.

Abstract: A method of decoding in a wireless receiver, a wireless transmission from a predefined user, the method comprising: receiving a wireless transmission signal (r(m)); determining a one or more interfering spreading codes (si(m)) contributing to the received wireless transmission signal (r(m)); estimating a one or more interferer symbols ({circumflex over (b)}i(m)) from the received wireless transmission signal (r(m)) and the or each interfering spreading codes (si(m)); calculating a one or more scaling factors (Pi(m)) at which the or each of the interferer symbols ({circumflex over (b)}i(m)) was originally transmitted; simulating an interference signal i(m) in the received wireless transmission signal (r(m)); removing the simulated interference signal i(m) from the received wireless transmission signal (r(m)) to produce a processed wireless signal (o(m)); and estimating a one or more symbols {circumflex over (b)}(m) transmitted by the predefined user in the processed wireless signal (o(m)).

Abstract: A method of improving sensitivity in the demodulation of a received signal by a receiver over an arbitrary measurement time epoch, said method comprising the steps of correlating said received signal with a local replica of pseudo noise code in a coherent fashion creating a correlation signal and utilizing a Viterbi phase state keying trellis demodulation with a variable resolution of phase states over 0 to 360° to demodulate the radio frequency phase trajectory of said correlation signal throughout the measurement time epoch for improving sensitivity in the demodulation of a received signal.

Abstract: A method is for decoding a pulse signal modulated through a transmitted reference modulation scheme. The modulated pulse signal may include, repetitively, a reference pulse followed by an information pulse delayed with a delay. The method may include subtracting or adding from the modulated pulse signal, a version of the modulated pulse signal delayed with the delay for obtaining a processed signal, and performing a non-coherent detection on the processed signal.

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: An aspect of the invention is a signal processing method for correlation computation between received signal samples, code replica and carrier replica. The method is characterized in that the method comprises steps of: mapping (110) received signal samples into a range of unsigned integers; separating (120) bits of the mapped N-bit sample sequences into N sequences of bits; performing at least one exclusive or (XOR) operation between a sequence of bits and the code; counting (140) number of bits having value 1 in the result of the exclusive or (XOR); remapping (150) the sum back into numeric range of the received signal samples; multiplying the remapped sum by carrier replica; and accumulating (170) the product of multiplication for an interval of at least a code epoch.

Abstract: Certain aspects of a method and system for achieving space and time diversity gain are disclosed. Aspects of one method may include modifying a generalization code of at least one pilot channel, to measure signal strengths for each of a plurality of received multipath signals. A portion of the plurality of received multipath signals may be combined based on the measured signal strengths. The signal strengths of the plurality of received multipath signals may be measured on a primary pilot channel by assigning its generalization code to zero. The signal strengths of the plurality of received multipath signals on a secondary pilot channel may measured by assigning its generalization code to a non-zero value.

Abstract: Signal sequence detection techniques are provided to enable a wireless communication device to detect presence of a sequence, such as a preamble sequence, in the presence of other transmission that would otherwise interference with the ability of the device to detect the sequence. At the wireless communication device, energy in a frequency band is received and a receive signal is generated from the received energy. The receive signal is divided into windows of a predetermined time duration. A running auto-correlation of the receive signal is computed to produce an auto-correlation sequence for a sequence to be detected in the receive signal. Data representing a mask is generated for a window based on the receive signal. The mask is applied to the auto-correlation sequence to filter out portions of the auto-correlation sequence that are outside of the mask. A position of sequence, e.g.

Abstract: Radiolocalization receiver for a satellite radiolocalization system like GPs, Galileo or the like, including a staged correlation and accumulation unit, in which the correlation data is biased in order to be to always non-negative. Thanks to this feature, the accumulated data grow monotonically during the accumulation. Overflow rate of a first correlation stage (100, 150-153) is scaled down respect to the rate of the input data. Thus the higher correlation stages (200, 154-158) can be used in multiplex. The bit-flip rate in memories is very low, with an effective reduction of dynamic power consumption. The logic structure of the accumulator is also simplified by the invention, thus further savings in silicon space and power are possible.

Abstract: Apparatus for recovering symbols from control and data channels corresponding to a plurality of users is described. Samples corresponding to control channel signals from multiple users are processed on a time shared basis with various control channel processing elements being reused multiple times to processes the samples and recover signals, e.g., symbols, corresponding to the plurality of users. While the control channel processing elements are used on a time shared basis, a separate data channel processing chain or module maybe provided for each of the plurality of users. In some embodiments the order of despreading and filtering is reversed for the control and data channel signal processing.

Abstract: A system and method of communicating signals is provided. The system includes a plurality of satellites, at least one receiver, and at least one satellite uplink station. The plurality of satellites include at least one active satellite. The at least one receiver is in communication with the plurality of satellites, and receives a signal from the at least one active satellite. The at least one satellite uplink station is in communication with the plurality of satellites, and transmits the signal and alters a frequency of the signal based upon a location of the at least one active satellite to reduce a Doppler frequency shift when activating and deactivating the plurality of satellites.

Abstract: To generate a pulse for ranging, a kernel is convolved with a spreading sequence. The spreading sequence is parametrized by one or more ordered (length, sparsity) pairs, such that the first sparsity differs from the bit length of the kernel and/or a subsequent sparsity differs from the product of the immediately preceding length and the immediately preceding sparsity. Alternatively, a kernel is convolved with an ordered plurality of spreading sequences, all but the first of which may be non-binary. The pulse is launched towards a target. The reflection from the target is transformed to a received reflection, compressed by deconvolution of the spreading sequence, and post-processed to provide a range to the target and/or a direction of arrival from the target.

Abstract: Precise operation of an accelerator operating member (7) is more difficult to perform in a reversing operation of a vehicle (1) as compared with an advancing operation. Therefore, behavior of the vehicle (1) is not smooth and thus tends to be unnatural. In the reversing operation of the vehicle (1), driving force output from an internal combustion engine (2) is limited in accordance with vehicle acceleration (D). At this time, it is possible to regulate the driving force of the vehicle (1) in conformity to the actual operation of the accelerator operating member (7) by the driver. In addition, limitation of the driving force is not executed in the advancing operation of the vehicle (1). At this time, the vehicle (1) can be driven in a state in which the driving force is comparatively small. Therefore, it is possible to prevent the behavior of the vehicle (1) from being unnatural.

Abstract: A method for the generation of a signal including a minimum of disturbances and noise is provided. A method for the detection of a signal including a minimum of disturbances and noise is also provided. An element of the signal is functionally dependent on at least one further element of the signal.

Abstract: A method is described to compensate for deviation error in a H-CPM sync or data burst received by a MLSE receiver in a communication device. The deviation error is estimated and matched filter coefficients are adjusted using the estimated deviation error. Metrics are determined for the current state using the adjusted matched filter coefficients. The state having the minimum metric is determined to be the most likely current state. The most likely previous state is similarly determined. The burst is reconstructed backward from the last state to the initial state. The metric is the squared magnitude of the difference between the channel estimate multiplied by the matched filter coefficient associated with one of the possible states and the current state. Timing and frequency errors are compensated for before estimation and correction of the deviation error. Pilot or sync symbols are used in estimating the deviation error.

Abstract: Systems (100) and methods (700) for processing a data signal in a communications system. The methods involve generating a first chaotic sequence at a transmitter (102). The methods also involve performing first basis function algorithms using the first chaotic sequence to generate first statistically orthogonal chaotic sequences. At least one sequence is selected from the first statistically orthogonal chaotic sequences for combining with a first data signal. The selected sequence is combined with a second data signal to obtain a modulated chaotic communication signal. The modulated chaotic communication signal is transmitted to a receiver (104). At the receiver, the received modulated chaotic communication signal is processed to obtain data therefrom. Notably, the signal processing generally involves performing a deterministic process (e.g., a Hidden Markov Model deterministic process).

Abstract: A low complexity RACH preamble detector is described herein. The RACH preamble detection algorithm uses the peak detection of the time domain correlation function through frequency domain processing. The frequency domain processing considers the reference signals generated directly from frequency domain CAZAC sequence or time domain CAZAC sequence with DFT conversion. A low-complexity poly-phase LPF along with down sampling is implemented before the FFT to reduce the required length of the long FFT operation N-folded.

Abstract: A MIMO transmitter has a modulator (40,41,42, 120, 122) a demultiplexer 100 arranged to divide the information into one or more demux streams for transmission over different ones of the channels, and a diversity splitter (110) to derive one or more sub-streams of the same information. A decorrelator (120) such as a scrambler (150, 155) decorrelates the sub-streams before or after the modulation. The arrangement is configurable to vary in use a ratio of demultiplexing and of diversity splitting. This balances between the gains from diversity and spatial multiplexing, without needing major changes to the transmit and receive processing.

Abstract: The present invention is a double-layer multi-carrier ultra-wideband wireless communication method, wherein the frequency band for ultra-wideband communication is divided into a plurality of sub-bands, then one or more sub-bands are used for data transmission, and the Orthogonal Frequency Division Multiplex (OFDM) multi-carrier transmission technology is used in each sub-band. In the transmitting party, the data symbols to be transmitted are allocated on M branches corresponding to the M sub-bands, and the OFDM modulation is implemented on the data symbols on each branch to obtain M branches of parallel data, then digital baseband multi-carrier modulation is implemented on the M branches of parallel data. Thereby, the spectrum of data on each branch is moved onto the digital sub-band corresponding to the radio sub-band one to one, so the digital baseband signal of the radio signal to be transmitted is obtained.

Abstract: Embodiments of the present invention provide a hybrid analog to digital converter that may include a DAC coupled to a hybrid analog to digital converter input; an integrator having an input coupled to the hybrid analog to digital converter input and the DAC, and generating an integrator output; a comparator coupled to the integrator output and having a comparator output; a successive approximation register coupled to the comparator output; and a counter coupled to the comparator output to generate an hybrid analog to digital converter output. The hybrid analog to digital converter may be operable as a successive approximation register converter and a continuous time sigma delta converter.

Abstract: A code division multiplex signal transmitter includes an operational circuit, a modulator unit and a multiplexer. The operational circuit adds up input transmission data on channels to produce resultant added data and modulates pieces of bit transmission data which are indicative of the values of the respective bits of the added data, when expressed in binary form, the pieces of bit transmission data being equal in number to the M bit positions of the added data expressed in binary form. The modulator unit includes modulators corresponding in number to the M bit positions of the added data in the binary form. A k-th modulator, where k is an integer of 1 to M, inclusive, modulates a k-th piece of bit transmission data to produce a k-th bit modulated signal whose amplitude level is 2k-1. The multiplexer multiplexes first to M-th bit modulated signals to produce a code division multiplex signal.

Abstract: A method for estimating the speed of a mobile device in a network is provided that includes selecting a correlation length from a plurality of possible correlation lengths. A correlation result is generated based on the selected correlation length. A speed estimate is generated for the mobile device based on the correlation result.

Abstract: To generate a pulse for ranging, a kernel is convolved with a spreading sequence. The spreading sequence is parametrized by one or more ordered (length, sparsity) pairs, such that the first sparsity differs from the bit length of the kernel and/or a subsequent sparsity differs from the product of the immediately preceding length and the immediately preceding sparsity. Alternatively, a kernel is convolved with an ordered plurality of spreading sequences, all but the first of which may be non-binary. The pulse is launched towards a target. The reflection from the target is transformed to a received reflection, compressed by deconvolution of the spreading sequence, and post-processed to provide a range to the target and/or a direction of arrival from the target.

Abstract: The present invention includes a method of determining a phase estimate for an input signal having pilot symbols. The method includes receiving a plurality of pilot symbols, and then multiplying two or more pilot symbol slots by corresponding correlator coefficients to correct a phase estimate of the input signal.

Abstract: Described herein are code-modulated multi-signal systems. In one embodiment, a multi-signal system receives multiple input signals and code-modulates each input signal with a unique code to distinguish the input signal from the other input signals. The input signals may come from multiple antennas, multiple sensors, multiple channels, etc. The code-modulated signals are then combined into a combined signal that is sent through shared blocks and/or transmitted across a shared medium in a shared path. After shared processing and/or shared transmission, the individual signals are recovered using matched filters. Each matched filter contains a code corresponding to one of the unique codes for recovering the corresponding signal from the combined signal. The recovered signals may then be inputted to additional processors for further processing.

Abstract: A two-dimensional filter arithmetic device comprises a picture memory, a line memory, a vertical filtering unit which includes nine first filter modules installed in parallel, a buffer for timing adjustments, and a horizontal filtering unit which includes four second filter modules installed in parallel. From the line memory, the pixel values of nine full pels per line are inputted in parallel to the vertical filtering unit, nine vertically-filtered values of half pels are generated and inputted to the horizontal filtering unit; thereby, four two-dimensionally-filtered values of half pels are generated.

Abstract: A system and method are provided for improving the performance of a beamforming antenna array in a wireless communications system. By observing a predetermined times of channel spatial signatures, one or more test spatial signatures are generated based on statistical analysis of the observed spatial signatures for predicting channel characteristics. A beamforming weight is derived based on the generated test spatial signatures for beamforming by an antenna subsystem of the wireless communication system.

Abstract: A device performs demodulation of control signals from multiple radio terminals, based on the correlations in the frequency domain between a predetermined code and the orthogonalized control signals and reference signals of the multiple radio terminals obtained by cyclic shifts of the predetermined code. The device includes: a demultiplexer which demultiplexes a reference signal component and a control signal component based on a correlation profile; a path detector which detects a path location or path locations for each radio terminal based on the power values of the reference signal components; extractor which extracts the correlation values of the reference signal components and the correlation values of the control signal components, respectively; and RAKE combiner which combines the extracted values.

Abstract: Direct detection of wireless interferers in a communication device for multiple modulation types. One or more radios implemented within a communication device is/are operative to receive and process wireless communications. A wireless communication signal is processed to extract symbols there from. Various symbols groups are processed in accordance with correlation processing to identify potential interferers (e.g., other communication devices using common portions of frequency spectra). Alternatively, matched filter processing (e.g., using a Barker matched filter in some embodiments) operates on the various symbol groups to identify some potential interferers. Various combinations of correlation processing and matched filter processing may be employed in other instances (e.g., using any of a desired means of comparison, combining, etc.) in considering interferers identified in accordance with each of these two means.

Abstract: Methods, systems, and apparatuses, and combinations and sub-combinations thereof, for down-converting an electromagnetic (EM) signal are described herein. Briefly stated, in embodiments the invention operates by receiving an EM signal and recursively operating on approximate half cycles (½, 1½, 2½, etc.) of the carrier signal. The recursive operations can be performed at a sub-harmonic rate of the carrier signal. The invention accumulates the results of the recursive operations and uses the accumulated results to form a down-converted signal. In an embodiment, the EM signal is down-converted to an intermediate frequency (IF) signal. In another embodiment, the EM signal is down-converted to a baseband information signal. In another embodiment, the EM signal is a frequency modulated (FM) signal, which is down-converted to a non-FM signal, such as a phase modulated (PM) signal or an amplitude modulated (AM) signal.

Abstract: A configurable all-digital coherent demodulator system for spread spectrum digital communications is disclosed herein. The demodulator system includes an extended and long code demodulator (ELCD) coupled to a traffic channel demodulator (TCD) and a parameter estimator (PE). The demodulator also includes a pilot assisted correction device (PACD) that is coupled to the PE and the TCD. The ELCD provides a code-demodulated signal to the TCD and the PE. In turn, the TCD provides a demodulated output data signal to the PE. The PACD corrects the phase error of the demodulated output data based on an error estimate that is fed forward from the PE. Accumulation operations in the ELCD, TCD, and PE are all programmable. Similarly, a phase delay in the PACD is also programmable to provide synchronization with the error estimate from the PE.

Abstract: The present invention relates to a method and a device for detecting active spreading codes for a signal in a communication system and estimating power of the active spreading codes. Further, the present invention ensures efficient interference cancellation. Multiple correlations are performed at a single level of a spreading code tree, the produced output samples are then observed at this level during a defined period, and a decision for the activity and power is met for all existing codes via extracting and processing information from these samples. At the correlation step, unitary fast Walsh Hadamard transformation is performed at practically the highest spreading factor in the system.

Abstract: In a wireless access network, a transmitter provides a pool of sequences having a reduced peak-to-average power ratio. Information to be transmitted is mapped to a selected at least one of the pool of sequences. The selected at least one sequence is transmitted over an orthogonal frequency division multiple access (OFDMA)-based wireless link of the wireless access network.

Abstract: Provided is an apparatus for channel equalization in frequency domain, including: a channel estimation unit for estimating a channel on received signal from outside, a channel matched filter for changing channel characteristic of the channel estimated by the channel estimation unit and the received signal to channel characteristic to meet condition required for noncausal filtering, a noncausal filter for changing the channel characteristic changed by the channel matched filter from nonminimum phase channel to minimum phase channel, a reverse channel calculation unit for calculating a reverse of the channel changed by the noncausal filter in frequency domain, and a frequency domain equalization unit for performing channel equalization with respect to the channel changed by the noncausal filter in the frequency domain by using the reverse obtained by the reverse channel calculation unit as coefficients of the frequency domain equalization apparatus.

Abstract: Embodiments related to cross-talk mitigation are described and depicted.

Abstract: The present invention relates to a method for detecting the presence or the absence of a spread spectrum signal in a frequency band of interest of a received signal, wherein: the autocorrelation function of said received signal is calculated for a set (S*) of non-zero time shift values (m); at least one cyclic correlation coefficient on (Rek?(m)) of the autocorrelation function is determined for said time shift values; the energy of the autocorrelation function is estimated from the quadratic sum of the values assumed by said cyclic correlation coefficient for said time shift values; the thereby estimated energy is compared with a predetermined threshold value and the presence or absence of said spread spectrum signal in the received signal is inferred from the result of the comparison.

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 system and technique for providing to flexible, programmable frequency estimators and spectrum analyzers that can operate over extremely large bandwidths and yet provide high spectral resolution are described. The acquisition time and hardware complexity of one technique scale as O(N), where N denotes the number of frequency bins acquired. Embodiments are disclosed in which architectures are implemented using exponentially-tapered transmission lines and filter cascades.

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: There is provided a method for generating an error signal for an automatic frequency control (AFC) loop in a Code Division Multiple Access (CDMA) system. Sign information relating to phase differences in received pilot signals is accumulated. In one embodiment, the accumulated sign information is compared against predetermined threshold levels. The error signal is generated when at least one of the predetermined threshold levels is satisfied. In a second embodiment, the accumulated sign information is decimated. An output of the decimating step is utilized as the error signal for the AFC loop.

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 multimode communication device with a shared signal path programmable filter and a method for utilizing a shared signal path programmable filter in a multimode communication device. Various aspects of the present invention comprise a first module adapted to receive a first communication signal (e.g., corresponding to a first communication protocol) and a second module adapted to receive a second communication signal (e.g., corresponding to a second communication protocol). A shared filter, communicatively coupled to the first and second modules, may be adapted to filter the first and/or second communication signals in accordance with a plurality of selectable sets of filter response characteristics (e.g., associated with the first and second communication protocols). A filter control module may be adapted to select a set of filter response characteristics from a plurality of such sets and program the shared filter to filter a communication signal in accordance with the selected set.

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: A system and method for transmitting a plurality of spread-spectrum signals over a communications channel having fading. The plurality of spread-spectrum signals are radiated by a plurality of antennas, with each antenna preferably spaced by one-quarter wavelength. A plurality of receiver antennas receive the plurality of spread-spectrum signals and a plurality of fading spread-spectrum signals. Each receiver antenna is coupled to a plurality of matched filters having a respective plurality of impulse responses matched to the chip-sequence signals of the plurality of spread-spectrum signals. A RAKE and space-diversity combiner combines, for each respective chip-sequence signal, a respective plurality of detected spread-spectrum signals and a respective multiplicity of detected-multipath-spread-spectrum signals, to generate a plurality of combined signals. The symbol amplitudes can be measured and erasure decoding employed to improve performance.