Abstract: A system and method to more efficiently compute updated Frequency Domain (FD) Minimum Mean Squared Error (MMSE) equalization weights in a multi-stage Parallel Interference Cancellation (PIC) receiver after initial interference cancellation. The updated equalization weights (which are to be used during re-equalization) can be obtained using the old equalization weights already computed for initial interference cancellation. There is no need to invert an nR by nR matrix (where nR is the number of receive antennas) at each stage of the PIC receiver during each iteration of equalization and decoding operations. Rather, the matrix to be inverted to obtain updated equalization weights may be of the dimension n×n (where “n” equals the total number of transmission layers in a transmission scheme used in the wireless network).

Abstract: This invention teaches to the details of an interference suppressing receiver for suppressing 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 suppression 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: Systems, devices, processors, and methods are described which may be used for the reception of a wireless broadband signal at a user terminal from a gateway via a satellite. A wireless signal may include a series of physical layer frames, each frame including a physical layer header and payload. The received signal is digitized and processed using various novel physical layer headers and related techniques to synchronize the physical layer frames and recover data from physical layer headers for purposes of demodulation and decoding.

Abstract: A method for mitigating a multi-path-induced error in a global navigation satellite system comprises, for a respective measurement epoch, obtaining respective representations of a composite signal including a plurality of value-pairs of the composite signal. The method further comprises, with respect to the measurement epoch: obtaining a plurality of coefficients for a set of linear equations based on the plurality of value-pairs of the composite signal; iteratively obtaining solutions for the set of linear equations, thereby solving for a code tracking timing offset, a time delay of a multi-path signal of the composite signal relative to its direct-path signal, and orthogonal representations of the multi-path signal; determining a phase error between the composite signal and the direct-path signal, due to the time delay, in accordance with the orthogonal representations of the multi-path signal; and correcting for the code tracking timing offset and the phase error.

Abstract: Linear symbol level equalisation is used to estimate a transmitted symbol vector xn(0) in an nth observation window yn of signals received from multiple users each using a different spreading code. An iterative conjugate gradient algorithm resolves a column vector z that satisfies Az=b, A being a square matrix and b being a column vector. The matrix vector product Apk used in each respective kth iteration of the algorithm is computed using at least one fast transform. The receiver or detector estimates a posterior mean {circumflex over (x)}LMMSE,n(0) from the computed column vector z, then utilises the estimated posterior mean to determine the transmitted symbol vector xn(0). The posterior mean {circumflex over (x)}LMMSE,n(0) may be estimated from matrix A and vector b. Different examples have the square matrix A with an inner or an outer product form; and have the fast transform as a fast Walsh-Hadamard transform and/or a fast (inverse) Fourier transform.

Abstract: Techniques for handling fingers with large delay spread through utility optimization are described. A first signal may be received, through a finger of a plurality of fingers in a receiver, at a time that is later than a reference time after a reference signal is received by a reference finger of the plurality of fingers. The reference signal may be included in an on-time group corresponding to a cell. The first signal may be included in a late group corresponding to a virtual cell. The first signal and the reference signal may be compared to one another. Based on the comparing, it may be determined whether to wait for additional signals in the late group or process the signals in the on-time group.

Abstract: Methods and systems for using pitch predictors in speech/audio coders are provided. Techniques for optimal pre- and post-filtering are presented, and a general result that post-filtering is more effective than pre-filtering is derived. A practical paired-zero filter design for the low-rate regime is proposed, and this design is extended to handle frequency-dependent periodicity levels. Further, the methods described provide a general performance measure for a post-filter that only uses information available at the decoder, thereby allowing for the optimization or selection of a post-filter without increasing the rate.

Abstract: A method and apparatus is provided for intra-PIT signal decomposition of a signal received with RF front end hardware. The method begins by aligning a signal received by RF front end hardware into integer multiples of a duration of a pseudorandom noise code sequence. A search grid is computed based on an integer multiple of the aligned signal. A plurality of initial ray parameters associated with the computed search grid is coarsely estimated. Using the coarsely estimated plurality of initial ray parameters, a fine estimation of the plurality of initial ray parameters is initiated utilizing stochastic search and optimization techniques. A stopping criteria statistic is computed by comparing a peak power of the search grid with a noise power present in the search grid. Finally, in response to determining the stopping criteria statistic being less than a stopping criteria threshold, processing a next integer multiple of the aligned signal.

Abstract: A system for and a method of wirelessly monitoring one or more patients can include transmitting ultra-wideband pulses toward the one or more patients, receiving ultra-wideband signals, and sampling the ultra-wideband signals. Sampling the ultra-wideband pulses can be performed with a sample rate that is less than the Nyquist rate. Impulse response can be estimated and/or recovered by exploiting sparsity of the impulse response.

Abstract: A method for performing joint detection includes adjusting a ranking order of codes in a matched filtering result, and a ranking order of column vectors in a system submatrix according to the power. The joint detection is performed using an adjusted matched filtering result and an adjusted system submatrix, and acquires demodulated signals corresponding to the codes. The codes that have high power will be demodulated first. This ensures accuracy of demodulation, inhibits erroneous propagation effect, and improves accuracy of the joint detection.

Abstract: A method for canceling adjacent channel interference includes: receiving signal of a first channel, where an interference signal of a second channel remains in the signal of the first channel, and the second channel and the first channel are adjacent channels; receiving a cancellation signal provided by the second channel for canceling the interference signal; filtering the received cancellation signal; adjusting a frequency of the filtered cancellation signal; multiplying the cancellation signal with the adjusted frequency by a gain factor to obtain a signal to be cancelled; and subtracting the signal to be cancelled from the signal of the first channel, and canceling the interference signal to obtain a signal to be decoded. According to the technical solutions provided in the embodiments of the present invention, interference signals of adjacent channels are cancelled, and the signal to noise ratio is improved.

Abstract: The present technique relates to a transmission device, a transmission method, a reception device, a reception method, a program, and a communication system which can realize a system capable of promptly addressing a newly-generated disturbance wave. A broadcasting device of the present disclosure includes: a reception unit which receives reception interference information notified from the reception device; a setting unit which sets a frequency of a notch to be provided in a transmission signal on the basis of the reception interference information that has been received; a modulation unit which provides the notch in accordance with the set frequency of the notch while at the same time generates a modulated signal by modulating information to be transmitted; and a send-out unit which sends out the modulated signal as the transmission signal.

Abstract: Aspects of the present invention include methods, systems, and computer-readable medium for canceling interference in wireless communication. The method includes receiving wireless CDMA communication signals using one or more antennas at least from a first entity via a first communication channel and a second entity via a second communication channel, determining a set of known characteristics associated with the first entity, the first set of characteristics comprising a first signal strength, a first synchronization information, and an first channel identification information, and determining an aggregate signal matrix based on signals received from at least the first entity and the second entity.

Abstract: Techniques are provided which may be implemented using various methods and/or apparatuses in a device comprising a receiver to scan a spectral band of a received signal comprising a desired signal contribution to determine whether signal data associated with at least a sub-band of the spectral band further comprises at least one undesired signal contribution. In response to determining that the signal data comprises at least one undesired signal contribution, the mobile station may initiate at least one notch filter to affect the undesired signal contribution in subsequent signal data associated with the received signal.

Abstract: A communication node (115) with is arranged to receive signals from at least one antenna (120). A frequency domain conversion is executed (201) for two or more antenna signals by receiving (201a) a continuous signal from one of the at least one antenna (120), splitting (201b) the continuous antenna signal into windowed signals, and performing (201e) a frequency domain conversion of the windowed signals. Then, a channel estimate based on a frequency converted pilot signal is provided (202) by extracting (202a) a pilot signal, splitting (202b) the pilot signal into windowed signals, performing (202d) a frequency domain conversion of the split pilot signal; and providing (202e) a channel estimate of the frequency converted pilot signal. Diversity combined signals are provided (203) by performing (203a) diversity combining based on the frequency converted windowed signals and the channel estimate, and by combining (203c) the diversity combined signals.

Abstract: A reception circuit that receives data in serial communications through a plurality of lanes includes a plurality of buffers provided for each of the plurality of lanes that each stores data received through corresponding lane, a multilane control circuit that detects the skew between the lanes, and outputs an adjustment instruction for adjusting a read address of a buffer and a deskew information indicating that a skew adjustment between which buffer the lanes is to be performed based on the detected skew, and a plurality of address control circuits provided for each of the plurality of lanes that each transmits the adjustment instruction to a corresponding buffer when receiving the deskew information, wherein the buffer that has received the adjustment instruction adjusting its read address.

Abstract: A method, an apparatus, and a computer program product for wireless communication are provided. The apparatus receives an intended signal from a first wireless device operating in a full-duplex mode, receives an interfering signal from a second wireless device communicating with the first wireless device, and reduces an interference of the received intended signal caused by the interfering signal by projecting a matrix of the received intended signal onto a space associated with the interfering signal.

Abstract: A coexistence system including a first transceiver module in a first network device, generating a first request signal that requests transmission or reception for the first transceiver module, and operating according to a first wireless communication standard. An interface, based on the first request signal, generates a first priority signal, which indicates a first priority level of first data signals. A second transceiver module is in the first network device and generates a second request and priority signals. The second transceiver module operates according to a second wireless communication standard. The second request signal requests transmission or reception for the first transceiver module. The second priority signal indicates a second priority level of second data signals. An arbitration module (i) based on the first and second priority levels, arbitrates the first and second request signals, and (ii) based thereon, selectively connects antennas to the first and second transceiver modules.

Abstract: Methods, systems, and devices for maximizing signal to interference plus noise ratio of a channel in a location tracking system. The methods, systems, and device may include tools and techniques for minimizing interference from adjacent samples at a receive filter, may include relaxing constraints at a transmitter. A receive filter or set of receive, or both, filters may be determined and utilized by specifying and or determining various transmitter, receiver, and channel characteristics. The receive filter and set of filters may be determined through an iterative approach involving one or more solution metrics.

Abstract: Techniques for sending signaling messages in a wireless communication network are described. In an aspect, a signaling message (e.g., a reduce interference request) may be sent by mapping it to at least one specific subcarrier among a set of subcarriers reserved for sending the signaling message. The at least one subcarrier may be selected based on the message value. A signal may be sent on the at least one subcarrier in multiple symbol periods to convey the signaling message. In another aspect, a reduce interference request may be sent based on an orthogonal resource among orthogonal resources available for sending reduce interference requests. In one design, an orthogonal sequence may be selected based on the request and may be spread across a resource segment. In another design, the reduce interference request may be processed to obtain modulation symbols, and each modulation symbol may be spread across multiple subcarriers in one symbol period.

Abstract: In one aspect, the teachings herein disclose a method and apparatus for signal quality reporting from a wireless apparatus that better reflects the actual interference cancellation efficiency expected at the wireless apparatus for a given transmission interval. In one example, the wireless apparatus knows or predicts the particular modulation and coding schemes (MCSs) that will be used in the transmission of one or more interferer signals for a transmission interval of interest. In turn, it uses those MCS values to estimate the actual interference cancellation efficiency the wireless apparatus will achieve with respect to those interferers. The wireless apparatus estimates and reports signal quality according to its estimated interference cancellation efficiency.

Abstract: An apparatus and method for a two-stage linear/nonlinear interference cancellation comprising processing a receive signal to produce a first descrambled signal; and processing the first descrambled signal to produce a detected signal. In one aspect, a first interference canceller module is used for processing the received signal and a second interference canceller module is used for processing the first descrambled signal. In one aspect, the first interference canceller is a linear interference canceller (IC) and the second interference canceller is a linear/nonlinear interference canceller (IC).

Abstract: This acquisition method is provided for acquiring a satellite signal emitted by a radio navigation satellite, the satellite signal containing a cyclic pseudo-random identification code specific to the satellite. The acquisition method includes the generation of a local code producing a replica of the identification code, and the production of a combined correlation (EDDC) of a received signal with the local code, the combined correlation corresponding to the linear combination of a first double delta correlation and of a second narrow correlation.

Abstract: A receiver architecture for processing spread spectrum signals. The receiver has an RF front end to receive and down convert a broadcast signal to an intermediate frequency carrier. The IF signal is digitized and provided to a processor (which may be a software-driven DSP, an ASIC or other embodiment) for processing. A given IF carrier is removed and the signal is low pass filtered. The signal is provided to a number of channels, each, for example, correspond to a unique transmitter. On each channel the sample rate is reduced to a predetermined fixed rate with timing mismatch compensated. The Doppler frequency shift, as estimated for the channel, is removed succeedingly. A locally generated copy of the spreading code used by the transmitter is applied to the carrier and Doppler removed signal at the predetermined fixed sample rate. The de-spread signal is used to provide estimates of the Doppler shift and for subsequent sample selection.

Abstract: A system that incorporates the subject disclosure may perform, for example, a method for receiving interference information from each of the plurality of communication devices detecting interference information in a plurality of segments of a radio frequency spectrum, correlating the interference information of the plurality of communication devices to generate correlated information, and identifying a plurality of interferers according to the correlated information. Other embodiments are disclosed.

Abstract: A receiver is provided that receives signals from a device under test (DUT) for one or more modes of operation. For each mode, the system detects beacon transmission signals from the DUT, and counts the number of beacons for a period of time. If the count is not consistent with an expected count, e.g. a stored value, the system may preferably provide an output to indicate that there is a problem with the DUT. If the count is consistent with the expected count, the system may preferably perform further testing for other modes of operation. If the count output of the DUT is consistent with expected counts over each of the operation modes, the system may provide an indication that the DUT has passed the beacon tests.

Abstract: Method and apparatus related to implementing and/or utilizing different polarization antennas with different corresponding average transmit power levels are described. Inter-cell interference is mitigated by having different cells with different power relationships between polarizations antennas. For example, a first base station transmits at a high average power level on its vertical polarization antenna and transmits at a low average power level on its horizontal polarization antenna. Concurrently, a second base station, which is adjacent to the first base station, transmits at a low average power level on its vertical polarization antenna and transmits at a high average power level on its horizontal polarization antenna. In some hexagonal deployment schemes a base station has at most two adjacent base stations using the same power level to antenna polarization direction relationship as it is using.

Abstract: A circuit for use in a complementary Golay sequence generator or in a complementary Golay sequence correlator includes an input configured to receive an input signal, a set of delay elements, including delay elements corresponding to respective delays of 1, 2, 4, 8, 16, 32, and 64, and a set of multipliers interconnected with the input and the set of delay elements. The set of multipliers is configured to apply weight factors, and the weight factors define the sequence 1,1,?1,1,?1,1,?1. The circuit also includes a pair of outputs configured to output, in response to the input signal, one of (i) a pair of complementary Golay sequences or (ii) a pair of correlation output signals, using (a) the set of delay elements and (b) the set of weight multipliers.

Abstract: An amplification circuit (100) comprising a first filter (102) and an LNA (110). The first filter (102) comprising an input (104) for receiving an input signal; a first differential output (106); and a second differential output (108). The first filter (102) has a differential mode of operation for frequencies in its pass-band (706, 806) and a common mode of operation for frequencies outside its pass-band (706, 806), and may be an acoustic wave filter. The LNA (110) comprising a first differential input (112) connected to the first differential output (106) of the first filter (102); a second differential input (114) connected to the second differential output (108) of the first filter (102); and an output (116) for providing an amplified output signal.

Abstract: A method for detecting multi-user signals including conducting a first energy burst detection detecting a first plurality of user signals as a first energy burst, attempting to decode a user signal from the first plurality of signals within the first energy burst, cancelling out a first user signal from the first energy burst if the first user signal is successfully decoded from the first energy burst, determining a second user signal to be discarded if the second user signal is not successfully decoded from the first energy burst, conducting a second energy burst detection detecting a second plurality of signals as a second burst, and iteratively cancelling out the first user signal successfully decoded from the first energy burst from the second energy burst, wherein the second energy burst detection is conducted when all user signals within the first energy burst are either cancelled out or determined to be discarded.

Abstract: A receiver communicating according to a wireless communication protocol standard for filtering a signal received at a single antenna. The receiver includes filter modules, receiver modules, and a summer. The filter modules receive from antennas multipath components of the signal as transmitted to the receiver. The signal includes bits of data. Each of the filter modules: receives corresponding ones of the multipath components of the signal as received at a respective one of the antennas; and according to the wireless communication protocol standard, filters the signal as received at the respective one of the antennas to generate a filtered signal. The receiver modules respectively receive the filtered signals. Each of the receiver modules combines the multipath components in the respective filtered signal to generate an output signal. Each of the output signals includes a respective version of the bits of data. The summer sums the output signals.

Abstract: The method disclosed herein is implemented in a radio receiver to detect an AWGN channel, where the radio receiver comprises a rake receiver. The radio receiver receives signals transmitted via a propagation channel from a transmitter, and determines that the propagation channel is an AWGN channel when a filtered version of a minimum value of a metric is lower than a threshold value. The metric relates to a difference between a normalized measured power profile of the propagation channel and a normalized power template, which normalized power template is dependent on predetermined sampling timing shifts and on rake finger positions within the rake receiver.

Abstract: A method of calculating combining weight vectors associated with a received composite information signal comprising at least one data stream transmitted from at least a first antenna and a second antenna is disclosed. The method starts with computing a parametric estimate of an impairment covariance matrix including at least a first impairment term associated with common pilots deployed by the first antenna and the second antenna respectively. The first impairment term captures effects of interferences between the common pilots, in addition to effects of interferences caused by each common pilot singly. The impairment covariance matrix further includes a data covariance term capturing effects of the at least one data stream and an interference term caused at least partially by contribution of thermal noise of receiver branches. Then the method computes the combining weight vector using the computed impairment covariance matrix.

Abstract: A wireless communication device includes a reception processing circuit including a weight coefficient computation circuit that includes a computation circuit to compute a weight coefficient which is used for removing a distortion of a reception signal caused by a multi-path, and which of each of fingers corresponds to each of a specified number of paths among a plurality of paths caused by the multi-path between the device and the opposing device, by iteratively performing a computation including a complex multiplication between a weight coefficient while being iteratively computed and a component of a correlation matrix, and a control circuit to cause the computation circuit to compute complex multiplications between a first (second) component of a pair of components having a complex conjugate relationship and a first (second) weight coefficient while being iteratively computed when the pair of components is present among components used for computing the weight coefficient.

Abstract: A method and arrangement are disclosed for acquiring a spread spectrum signal produced by means of transmitter-end spreading of a bit sequence using a spread code signal, which provide for the reception of the spread spectrum signal; provision of a receiver-end spread code signal which corresponds to the transmitter-end spread code signal; performance of polyphase correlations for respective different code phases which give rise to polyphase correlation results which are each associated with different code phases; filtration using at least two of the code phases; determination of an extreme value in the filtered polyphase correlation results, and determination of the code phase which is associated with the extreme value.

Abstract: Systems and methods for generating a CDMA signal s(t) comprising N components involves assigning to each of the N components one unique spreading sequence an selected from a set of M spreading sequences with M?N, modulating the symbols dn of each component on the assigned unique spreading sequence an, and combining the N symbols dn each being spread with its own unique spreading sequence an to a CDMA signal s(t). The assigned spreading sequences an are selected such that all selected pairs within the set of N spreading sequences are orthogonal or very close to be orthogonal so that cross-correlation components between all spreading sequences an are close to zero or zero.

Abstract: A wireless receiving apparatus includes a spurious component extraction unit, and a spurious cancellation unit. The spurious component extraction unit is configured to cancel a desired wave with a multi-antenna configuration, and extract spurious components. The spurious cancellation unit is configured to cancel spurious in received signals by using the spurious components extracted. A first correlation unit in the spurious component extraction unit finds a correlation between an output of the spurious extraction unit and an output of the spurious cancellation unit.

Abstract: The invention relates to the field of radio signal receivers for use in wireless communication networks. In particular to a receiver unit having at least one antenna input for receiving multipath radio signals via a radio unit and at least one antenna from one or more user equipments is provided. The receiver unit comprises: a despreading unit configured to despread a multipath radio signal in the received multipath radio signals using a number of despreading fingers corresponding to a number of delay positions in the multipath radio signal which corresponds to a number of paths in the multipath radio signal, and a combining unit configured to apply at least one weight to the output of each of the number of allocated despreading fingers and combine the weighted outputs into a resulting equalized radio signal.

Abstract: A method including: using both dedicated circuitry and a programmable processor system for acquisition of a communication channel; and using the dedicated circuitry for tracking the acquired communication channel while using the programmable processor system for hosting an application that uses information dependent upon data dependent on the acquired communication channel.

Abstract: A method and apparatus for determining operating modes in a receiver is described herein. A delay searcher in the receiver detects a signal image in the received signal. When the receiver is a RAKE receiver, a plurality of RAKE fingers coherently combine time-shifted versions of the received signal at different delays. Alternatively, when the receiver is a chip equalization receiver, an FIR filter coherently pre-combines the signal images in the received signal. A processor determines delays. In particular, the processor generates a first signal quality metric for a single-delay receiver mode, and generates a second signal quality metric for a multi-delay receiver mode. Based on a comparison of the first and second signal quality metrics, the processor selects the single-delay or the multi-delay receiver mode for processing the signal image.

Abstract: A base station includes a reference signal sequence generator configured to generate a reference signal sequence for each of n antenna ports using one initialization seed, n being a positive integer. The base station also includes n spreaders. Each spreader corresponds to a respective one of the n antenna ports and is configured to receive a respective reference signal sequence for the respective antenna port from the reference signal sequence generator and spread the respective reference signal sequence using a respective Walsh code. The base station further includes n resource element mappers. Each mapper corresponds to a respective one of the n antenna ports and is configured to receive a respective spread reference signal sequence from a respective spreader and map the respective spread reference signal sequence to a set of reference signal resource elements corresponding to a respective antenna port.

Abstract: An antenna system and method utilize an evaluation branch circuit and an implementation branch circuit. These circuits are each connected to both a first antenna input and a second antenna input. An output of the evaluation branch circuit is in communication with a controller while an output of the implementation branch circuit is in communication with a receiver. Each branch circuit includes at least one signal conditioner to change an electrical characteristic of RF signals received from antennas via the antenna inputs. The evaluation branch circuit, controlled by the controller, changes the electrical characteristics of the RF signals in a variety of different ways to discover an optimized evaluation RF signal. Once the optimized evaluation RF signal is determined, the implementation branch circuit is controlled, by the controller, to produce an optimized implementation RF signal in accordance with that discovered by the evaluation branch circuit.

Abstract: Aspects of a method and system for interference suppression using information from non-listened base stations are provided. A wireless communication device may be operable to receive a raw signal comprising one or more desired signals from one or more serving base transceiver stations (BTSs) and comprising one or more undesired signals from one or more non-listened BTSs. The wireless communication device may be operable to generate first estimate signals that estimate the one or more undesired signals as transmitted by the one or more non-listened BTSs, generate an interference suppressed version of the raw signal based on the first estimate signals, and recover the one or more desired signals from the interference suppressed version of the raw signal. The non-listened BTSs may comprise one or more BTSs that are not serving the wireless communication device and are not involved in a hand off of the wireless communication device.

Abstract: Interference cognitive devices are described. An interference cognitive device can be collocated with a transmitter of an interference cognitive transmitter (ICT), as receive chains or portions thereof at the ICT. An interference cognitive device can also be remote with respect to the transmitter, which operates in an interference cognitive network and receives data directly or indirectly from the interference cognitive device. The ICT uses the data to mitigate interference while continuing to operate in accordance with a performance metric.

Abstract: Methods and apparatus are disclosed for receiving a diversity transmitted signal using a Rake or G-Rake receiver in a radio system. Signals are diversity transmitted in a first and second symbol period by two or more antennas. One or more receive antennas receive the diverse transmit signals. Weights are generated to account for the correlation between the channels over which the diverse transmit signals are transmitted in the first and second symbol period and are used to weight the received signals. The weighted signals are then fed to a mutual receiver.

Abstract: A method, receiver and program for processing radio signals to identity an n-ray channel condition. The method comprises: receiving signal samples and estimating a plurality of channel taps from the samples; estimating for each of the channel taps a signal power and a disturbance power; filtering the signal power to provide a filtered signal power quantity; filtering the disturbance power to provide a filtered disturbance power quantity; using the filtered power quantities to determine n strongest channel taps; generating first and second comparison parameters using the strongest channel taps and at least one other channel tap; providing a comparison result based on the first and second comparison parameters and a threshold value, and; identifying an n-ray channel condition from the comparison result.

Abstract: A navigation system includes a correlation engine configured to despread a received signal. The correlation engine includes a correlator configured to evaluate the received signal against a replica signal to produce a correlation result, and a packet encoder configured to produce a packet comprising a destination address, a source address, and the correlation result. An input/output interface is configured to provide the packet to another component in the navigation system.

Abstract: A receiver circuit provides improved noise estimation processing by at least partially removing receiver frequency error bias. An initial noise estimate is compensated using an error term based on the observed receiver frequency error, and the resulting compensated noise estimate can be used to improve other signal processing in the receiver. For example, the receiver may use compensated noise estimates to generate signal quality estimates, e.g., Signal-to-Interference (SIR) estimates, having improved accuracy. Additionally, or alternatively, the receiver may use the compensated noise estimates to generate RAKE combining weights having improved noise suppression characteristics. In an exemplary embodiment, the initial noise estimate is a noise correlation matrix generated from a received reference signal, e.g., pilot symbols, and the error term is an error matrix directly generated using the observed receiver frequency error and channel estimates taken from the reference signal.

Abstract: An interference cancelling receiver combines data from multiple paths after aligning to transmitter timing, and uses either an equalizer or a Rake receiver to compute symbol estimates. Interference estimates are generated from the symbol estimates, and multiple interference estimates are combined after re-aligning the interference estimates to receiver timing. At least two segments of symbol estimates are computed for each segment of interference cancelled data. Various techniques may be employed for controlling the latency and sequencing of these operations, and the subsystems within the canceller may use different processing clock speeds.

Abstract: A method and apparatus are provided for cancelling interferences of a received MIMO RF signal. The method includes: receiving a signal y; an initial step of obtaining, from the received signal y, at least one data representative of the received signal, called decoded data; computing the decoded data as a function of at least one predetermined criterion, delivering feedback data and a feedback decision; and, as a function of the feedback decision, at least one iteration of the following steps: constructing a set of feedback symbols from the feedback data; obtaining, from the set of feedback symbols, at least one data representative of a feedback decoded signal, called feedback decoded data; computing the at least one feedback decoded data as a function of the at least one predetermined criterion, delivering the feedback data.