Abstract: An electronic apparatus according to the present invention includes two modules which decode high frequency analog signals. Furthermore, each of the modules is provided with an RF section at a position away from the center of the module in either longitudinal direction to carry out radio communications using high frequencies. In this electronic apparatus, the two modules are arranged so that their longitudinal sides extend parallel with each other in opposite directions. The two modules are also misaligned with each other in the longitudinal direction so that the RF sections lie away from each other and so that connectors to which signals subject to noise interference are inputted lie away from each other.

Abstract: A transceiver used in a communications system includes a transmitter having a transmit input that is split into a transmit I component and a transmit Q component; a receiver having a receive input that is split into a receive I component and a receive Q component; a switching network configured to input the transmit I component, the transmit Q component, the receive I component and the receive Q component; and to output a sampled sequence; an analog to digital converter configured to receive the sampled sequence and to output a digitized data stream; and a digital signal processor configured to receive the digitized data stream and process the digitized data stream.

Abstract: A multimode wireless receiver circuit (10) includes multi-receiver control and interference detection logic (50) and least two separate receivers: a first receiver (20) associated with a first radio access technology and a second receiver (30) associated with a second radio access technology. The multi-receiver control and interference detection logic (50) simultaneously controls the second receiver (30) to detect an interference blocker signal (100), while the first receiver (20) receives at least a portion of the wireless signal (80) and the interference product signal (90). In response to the second receiver (30) detecting the interference blocker signal (100), the multi-receiver control and interference detection logic (50) adjusts at least one operating condition of the first receiver (20) such that the interference product signal (90) received by the first receiver (20) is reduced.

Abstract: An RFID reader accessible thorough a personal computer and includes a PC card interface and a controller both operating according to clock signals from a crystal oscillator. The RFID reader further includes a linearized power amplifier modulator in a transmit path, a receive chain capable of demodulating EPCglobal Class_1 and Class_0 signals from RFID tags, and an integrated switching device for selecting one of a plurality of antenna for transmitting or receiving RF signals.

Abstract: A band edge amplitude reduction system changes the filtering characteristics of a receiver based on the amplitude of signal(s) adjacent to an edge of the operating band of the receiver and/or of signals not under the power control of the receiver. For example, the receiver measures the power level over a bandwidth at the band edges of the operating band of the receiver. If the signals adjacent to the operating band are strong enough relative to the signal power within the operating band, overload protection circuitry changes the filtering characteristics of the receiver to improve the attenuation of the signal(s) from the adjacent band(s). In certain embodiments, the overload protection circuitry switches in filter(s) with a narrower bandwidth to attenuate the signal(s) from adjacent band(s) at the edge(s) of the operating band of the receiver, thereby preventing interference with or the overload of the receiver by signals from outside the operating band and/or not under the power control of the receiver.

Abstract: A method for I/Q mismatch calibration of a receiver having an I/Q correction module with correction parameters, comprising the steps of generating a test signal containing a single tone waveform with frequency of a carrier frequency plus a predetermined frequency, applying I/Q demodulation to reduce the central frequency of the test signal and outputting a demodulated signal, converting the demodulated signal to a digital signal, obtaining measures of the digital signal respectively indicative of the frequency response of the digital signal at the plus and minus predetermined frequencies, and calculating the set of the correction parameters for the I/Q correction module based on the measures.

Abstract: The present invention provides a synchronous demodulation apparatus of a base transceiver station in an Interim Standard-2000 (IS-2000) system, including a first synchronous demodulation unit, a received signal delay unit, an interference signal regeneration unit and a second synchronous demodulation unit. In comparison with an asynchronous demodulation apparatus used in an Interim Standard-95 (IS-95), it is possible for the inventive apparatus to improve a reception function approximately 3dB and ultimately increase the number of subscribers.

Abstract: The invention relates to a method of suppressing pulsed signals in particular of DME or TACAN type present in the radio signals received (Ue) by a radio-frequency receiver, characterized in that the reception frequency band of the receiver is divided into frequency sub-bands corresponding to the transmission channels of the pulsed signals, in that the presence of the pulsed signals and the transmission channel of said pulsed signals in the frequency sub-bands are detected, and in that the frequency sub-band comprising the detected pulsed signals is filtered over the duration of the pulsed signal so as to eliminate said pulsed signals pulse type.

Abstract: A receive front-end module having one or more 2 GHz Rx paths and one or more W-CDMA Rx paths for use in a portable communication device, such as a mobile phone or a communicator device. The module comprises at least two feed points operatively connected to two electrically separate antennas for receiving communication signals. The module also comprises filters for filtering the communication signals in corresponding frequency band, and means for providing cross-band isolation. The cross-band isolation is achieved by using linear amplifiers in different signal paths, for example. Advantageously, the module comprising three signal paths so that one or more modules can be used together to achieve MIMO/diversity functionality.

Abstract: The present invention is directed to a channel calibrator and a method of calibrating in-phase and quadrature phase channels for use with a quadrature mixing receiver. In one embodiment, the channel calibrator includes a balancer and an equalizer. The balancer reduces frequency dependent imbalance between an in-phase channel and a quadrature phase channel associated with the receiver. The equalizer decreases frequency independent mismatch between the in-phase channel and the quadrature phase channel.

Abstract: A method is provided for realizing, in a radio transmission system, a carrier synchronization and for cancelling one or more co-channel interfering signals from a received main signal, in which a synchronous down-conversion of the received main signal and of each of the interfering signal is performed to obtain respective intermediate frequency signals; and then a synchronous demodulation of the intermediate frequency signals so obtained is carried out.

Abstract: A digital radio frequency receiver capable of receiving RF signals at a plurality of signal strengths thereby extending the dynamic range of the receiver without introducing a control loop while allowing a stable gain control algorithm to be implemented in software is described. Various embodiments of a digital radio receiver process a range of signals outside normal analog to digital converter capabilities and bypass the delays resulting from gain control loops.

Abstract: A discrete Fourier transform (DFT) filter bank with stack shift capability, configured, for example, as an analyzer, but equally applicable to a synthesizer, and implemented as a polyphase filter. The DFT filter bank includes a complex modulator for multiplying the input signals x0(m), x1(m) . . . xM?1(m) by a complex modulator e?2?ko(m). In order to keep the coefficients for the polyphase filter real, the coefficients are modulated by a DFT twiddle factor e?2?ko?/M. The use of the DFT twiddle factor enables the hardware to be reduced significantly. For example, for an 8 phase 203 tap filter, only 8 selectable negators are required as opposed to 211 for known DFT filter banks.

Abstract: There is provided a transmit antenna array device with at least two antennas and a method thereof in which a transmission beam is appropriately formed based on a weight vector to be transmitted to a specific mobile station in a mobile communication system. For this purpose, a base station device has a reverse processor for processing a reverse signal received through the antenna array, a forward fading information extraction unit for extracting forward fading information from the received reverse signal, a beam formation controller for generating a weight vector for formation of a transmission beam using the forward fading information and the received reverse signal, and a forward processor having a transmission beam generator for generating a transmission beam for a transmission message based on the weight vector.

Abstract: The inventive receiver has a receiving branch for each of the two signals (EH, EV) and a demodulator (MHE, MVE) and means (SH, SV) for synchronising the phase of the received signal (EH, EV) with the transmitting phase are provided in said branches, respectively. Polaristion decouplers (XPIC-VH, XPIC-HV) which compensate cross-polar crosstalk between the two received signals (EH, EV) are provided for both of the receiving branches. The polarisation decoupling (XPIC-VH, XPIC-HV) of the two received signals (EH, EV) takes place after they have been demodulated (MHE, MVE) and before they have been phase-synchronised (SH, SV) so that the receiver can function as inexpensively as possible in terms of the components that it requires and so that it can also compensate cross polar channel crosstalk for circular QAM signal constellations.

Abstract: The present invention employs training sequence hopping in a cellular communications system to permit tight frequency reuse by minimizing or avoiding co-channel interference and/or other signal degrading phenomena. During a first portion of a transmission, e.g., a first burst, a first training sequence is used. During a second portion of that transmission, e.g., a second burst, a second different training sequence is used. Different training sequences are used for different portions of the transmission according to a predetermined training sequence hopping pattern and with a predetermined number of training sequences. The portion duration can extend for the length of a burst, for more than one burst, for a speech frame, or for some other time period.

Abstract: A half duplex radio transceiver comprises a transmitter (100) and a low IF receiver (200). The difference between the transmit frequency and the receive frequency is equal to the low IF. A common frequency generator (300) is shared between the transmitter and receiver without needing to be retuned. An upconversion signal at the transmit frequency is used for down conversion in the receiver. Transceivers at opposite ends of a communication link, such as in a master/slave network, have their transmit and receive frequencies interchanged. Optionally a transceiver may be configurable to either form e.g. as either a master of a slave station. Channel sensing for Carrier Sense Multiple Access (CSMA) may be performed on the transmit frequency without retuning the receiver.

Abstract: A dual channel downconverter that includes a two-channel heterodyne receiver architecture for downconverting two frequency-agile, pulsed RF signals to identical fixed IF signals without the use of a tunable local oscillator. This accomplishes downconversion while preserving, in the IF output signals, any amplitude modulations present in the RF signals. The device also preserves phase difference changes present in the RF signals while rejecting the phase modulations common to those input signals. The present device facilitates complex response measurements of pulsed two-port RF devices while operating in a target system such as a radar transmitter, including insertion gain, insertion phase, residual phase noise, error vector magnitude, AM noise, and group delay, all with increased accuracy, good repeatability, good dynamic range, and decreased measurement time.

Abstract: A receiver for rejecting an image signal is provided that does not require a phase-shifter and that requires less mixers than prior receivers. Thus, the phase imbalances and gain mismatches imparted by phase shifters are avoided, and harmonics due to non-liner effects in the mixers are reduced.

Abstract: A waveform reconstruction circuit receives an rf signal from an antenna, digitizes it, and then generates an undistorted reconstructed waveform. The reconstructed waveform can then be conventionally mixed and demodulated to extract useful signal information with enhanced receiver fidelity and sensitivity.

Abstract: The present invention utilizes a dual polarization reception system (200) that utilizes the energy available in orthogonal polarizations to effectively increase link margin, thereby allowing for adequate signal quality reception in difficult environments. A co-polarized and a cross-polarized signal are separately downconverted and demultiplexed. The signals from each demultiplexed output are then sampled and weighted. The weighted samples for each polarity are combined in soft decision combining/decoding circuitry (255, 360), and this circuitry determines the most likely state of a received symbol's transmitted value.

Abstract: Disclosed is a method and apparatus of transmit diversity that is backward compatible and does not significantly degrade performance in additive white guassan noise (AWGN) conditions using a transmission architecture that incorporates a form of phase sweep transmit diversity (PSTD) referred to herein as biased PSTD. Biased PSTD involves transmitting a signal and a frequency swept version of the same signal over diversity antennas at different power levels. By transmitting the two signals at different power levels, the depths of nulls normally seen in AWGN conditions when PSTD is utilized is reduced and performance degradation in AWGN conditions is mitigated.

Abstract: A system and method for reducing multi-path distortion of an M-ary communication signal is implemented with M×N parallel processors, a multi-path estimator, a metric selector and a decision processor. Parallel processors process each combination of possible signal symbols M and hypothesized guard times N, the output of the processors are supplied to the multi-path estimator which estimates the actual multi-path distortion of the transmitted symbol. The metric selector selects the processors with a guard time Gn most closely approximating the estimate from the multi-path estimator. The selected outputs are used in a decision processor to determine the transmitted symbols. The selected outputs are low passed filtered.

Abstract: A system that provides packaging for a surface acoustic wave filter in such a way that the surface acoustic wave filter is capable of integration with a number of additional electronic devices on an integrated substrate. The surface acoustic wave filter is mounted in a “flip chip” configuration that enables the surface of the surface acoustic wave filter to be protected from a molding compound during and after the encapsulation of the surface acoustic wave filter and other circuitry contained on the integrated substrate. The manner in which the surface acoustic wave filter is packaged provides a great reduction in cost and occupied real estate on the integrated substrate, in that, the surface acoustic wave filter is mounted in such as way as not to require conventionally used ceramic packaging that encases the surface acoustic wave filter. An air gap is preserved between the surface acoustic wave filter side of the surface acoustic wave filter and the integrated substrate on which it is mounted.

Abstract: Method and system are disclosed for detecting a situation where it is likely that additional multipath components are available in the channel, but are not included in the RAKE processing. In some embodiments, the invention uses the interference estimates for all RAKE fingers associated with tracked multipath components to detect the fraction of the available signal energy that is captured by the path searcher. The invention provides an activation signal to the path searcher if the fraction of the available power that is captured by the tracked paths falls below a predefined threshold.

Abstract: Techniques for multiple access differential frequency-hopped spread spectrum (MA-DFHSS) aided by multiuser detection (MUD) are disclosed. An initial DFH decoding is performed to provide data estimates for each user represented in a received co-channel signal. Interference cancellation is then performed using MUD, thereby providing an interference-cancelled signal. Data estimates remaining are then re-decoded. Iteration on the interference cancellation and re-decoding can be carried out to satisfy a particular rule of iteration, although iteration is not always necessary. The final decoded signal can then be provided to its destination.

Abstract: A radio system (10) and radio system (1, 2) in which the value of parameters for a model of a received multipath signal transmitted by a remote station (20) are estimated. A sounding signal transmitted and received by the radio station is used to derive data about the reflecting environment and this data is incorporated into the model after scaling it to represent the multipath signal received from a remote station. Optionally or alternatively the remote station may transmit a sounding signal and derive data about its reflecting environment and transmit this data to the radio station, The model may incorporate both sets of derived data, particularly if they are uncorrelated. The values of the resulting parameters are exploited in applications such as ranging, location or equalization.

Abstract: A receiver with reduced near field noise is described. The receiver has a far range receiving section configured to sense a desired signal that includes near field noise. The receiver further includes a near range receiving section configured to sense a near field noise reference signal. An adaptive noise canceller (ANC) of the receiver is configured to detect the magnitude of an error vector from the far range receiving section. The ANC is configured to adjust the phase and gain of the near field noise reference signal in response to the magnitude of the error. Accordingly, the ANC can generate a corrected near field noise reference signal that is added to the desired signal with an adder. The near field noise is canceled by the addition of the corrected near field noise signal. The ANC uses a least mean square technique to determine the amount of correction needed.

Abstract: A radio receiver (100) has an IF (intermediate frequency) filter (200) for automatically adjusting its intermediate frequency. The filter (200) includes a filter bank (304), an accumulative sub-band formation (322) and an accumulative sub-band power estimator/switch control (324). The filter bank (304) generates sub-bands, each sub-band having a predetermined frequency range. The accumulative sub-band formation (322) selectively sums the sub-bands to provide lowpass filters having incrementally increasing bandwidth. Power estimates of the lowpass filters are used to determine which lowpass filter output is appropriate for adjacent station interference. Also, if there is no adjacent station interference, the IF filter (200) selects the appropriate filter output depending on the signal strength of the desired station.

Abstract: An improved method of predistorting a transmit signal is disclosed whereby the distortions occurring in all nonlinear subassemblies are compensated for using a particularly suited feedback signal. Also disclosed are a transmitter, a transmitting station, and a communications system using the method. The transmit signal, before being converted to the desired radio frequency, is digitally predistorted at baseband by digital signal processing means which are controlled by the feedback signal. This signal is generated by a detector measuring the spectral power of the transmit signal at the desired radio frequency both within a first frequency range, which lies within the transmission spectrum, and within a second frequency range, which lies outside the transmission spectrum. The digital predistortion disclosed is flexibly parameterized and is adapted by the feedback control to the current behavior of the transmitter subassemblies.

Abstract: A compensating part compensates for deviations on transmission paths, and a pre-deviation signal combining part or a post-deviation signal combining part combines signals on the transmission paths before or after having the deviations applied thereto, wherein the compensating part performs compensation for the deviations based on output of the pre-deviation signal combining part or post-deviation signal combining part and the signals on the transmission paths to be compensated.

Abstract: A structure for preventing intermodulation interference in satellite transmission is characterized in that a frequency subtraction is executed at a first mixer and a local oscillator on one of the received satellite vertical and horizontal polarized signals to obtain a first mid-band, while a frequency subtraction is executed at a second mixer and a first-stage local oscillator on the other received signal to obtain a reverse-phase signal thereof, and a frequency addition is executed at a third mixer and a second-stage local oscillator on the reverse-phase signal to obtain a second mid-band, and that second and third harmonic differences between a frequency obtained by subtracting the oscillating frequency of the second-stage local oscillator from the oscillating frequency of the first-stage local oscillator and the oscillating frequency of the local oscillators do not fall in the first and the second mid-bands, respectively, and an intermodulation interference is prevented.

Abstract: A structure for reducing intermodulation interference in satellite signal transmission includes receiving antennas for receiving satellite polarized signals, an RF amplifying system for amplifying and down-converting the received signals, first and second mixers and a first-stage common local oscillator for executing a frequency subtraction, mid-frequency amplifiers and low-pass filters for amplifying and filtering signals output from the first and second mixers to generate a mid-band, a third mixer and a second-stage local oscillator for executing a frequency addition, a band-pass filter for filtering and isolating the resultant signal, and a fourth mixer and a third-stage local oscillator for executing another frequency subtraction, a high-pass filter for filtering the resultant signal to generate another non-repeated optimal mid-band, and a multiplex adder for combining the two mid-bands.

Abstract: A cosite interference rejection system allows cancellation of large interfering signals with an optical cancellation subsystem. The rejection system includes an interference subsystem coupled to a transmit system, where the interference subsystem weights a sampled transmit signal based on a feedback signal such that the weighted signal is out of phase with the sampled transmit signal. The optical cancellation subsystem is coupled to the interference subsystem and a receive antenna. The optical cancellation subsystem converts an optical signal into a desired receive signal based on an interfering coupled signal and the weighted signal. The weighted signal is therefore used to drive the optical cancellation subsystem. The rejection system further includes a feedback loop for providing the feedback signal to the interference subsystem based on the desired receive signal.

Abstract: Spatial and temporal characteristics of received radio signals in a multiple user radio system can be estimated based on signals received from the users. In one embodiment, the invention includes measuring radio frequency signals received at different elements of an antenna system over time, the received signals corresponding at least in part to transmissions received from a system user, accumulating the signal measurements into a first matrix, and generating a second matrix representing the transmissions of the system user. The invention further includes cross-correlating the first and second matrices to form a first cross-correlation matrix, cross-correlating the first matrix with itself to form a second cross-correlation matrix, and multiplying the second cross-correlation matrix with a product of the first cross-correlation matrix to form a fifth matrix in which the elements of the fifth matrix characterize the radio channel traversed by transmissions of the system user.

Abstract: Described herein is a method and apparatus for transmission that provides the performance of space time spreading (STS) or orthogonal transmit diversity (OTD) and the backwards compatibility of phase sweep transmit diversity (PSTD) without degrading performance of either STS or PSTD using a symmetric sweep PSTD transmission architecture. In one embodiment, a pair of signals s1 and s2 are split into signals s1(a) and s1(b) and signals s2(a) and s2(b), respectively. Signal s1 comprises a first STS/OTD signal belonging to an STS/OTD pair, and signal s2 comprises a second STS/OTD signal belonging to the STS/OTD pair. Signals s1(b) and s2(b) are phase swept using a pair of phase sweep frequency signals that would cancel out any self induced interference. For example, the pair of phase sweep frequency signals utilize a same phase sweep frequency with one of the phase sweep frequency signals rotating in the opposite direction plus an offset of ? relative to the other phase sweep frequency signal.

Abstract: A method (500) and a mobile station (160) for reporting multi-path signals based on a report window are described herein. The mobile station (160) may determine a distribution of a plurality of multi-path signals observed by a receiving unit (220) within the mobile station (160). The mobile station (160) may determine a report window based on the distribution. Based on the report window, the mobile station (160) may report at least one of the plurality of multi-path signals.

Abstract: A radio station (10) in which the value of parameters for a model of a received multipath signal are estimated, the model comprising a value representative of the perpendicular distance between the plane of the reflecting surfaces (40, 50) and the radio station. This perpendicular distance may be measured from the round trip delay of a sounding signal transmitted by the radio station. The amount of computation is reduced by applying constraints to the parameters, and these constraints may comprise this perpendicular distance. The constraints may also be a function of parameters such as the path length, angle of arrival or amplitude of the direct path signal, and the amplitude of reflections of the sounding signal. The values of the parameters may be estimated initially by analysis of the received signals, followed by a parameter estimation process. The values of the resulting parameters are exploited in applications such as ranging, location or equalisation.

Abstract: An amplification circuit for a wireless base station is provided. The amplification circuit includes a first port adapted to communicate signals to and from an antenna and a second port adapted to communicate signals to and from a base station. The amplification circuit further includes a first path and a second path with each path coupled between the first and second ports. The first path includes at least one bandpass filter and an amplifier that pass and amplify upstream signals in a first frequency band. The second path includes a filter that stops upstream signals in the first frequency band and passes upstream signals in at least a second frequency band and downstream signals in at least third and fourth frequency bands.

Abstract: The present invention, illustrated in various embodiments, provides mechanisms for transferring data in wireless communications systems. In one exemplary embodiment, the data is transferred in an access point (AP) used in a wireless local area network (WLAN), which comprises a wireless communication system connected to a local area network (LAN). The access point includes a baseband chip capable of adapting various radio frequency (RF) units. Each RF unit in turns includes a plurality of RF sub units connected in a daisy-chain manner. Each RF sub unit is also connected to at least one antenna. The access point thus includes a number of antennas that, together with the RF units and the baseband chip, form a smart antenna. In a receiving mode, the data received from the smart antenna travels through the RF sub units in each RF unit, and the data from the RF units travels to the baseband chip.

Abstract: A receiver for the third-generation (“3G”) CDMA wireless system is disclosed. The receiver is adapted to mitigate the correlated interference by adaptive antenna process which will maximize the signal-to-interference-plus-noise ratio. After the mitigation of correlated interference from first step space process, the second step is to counter fading with MRC which is optimum after the mitigation of correlated interference. After these first two steps of interference mitigation by adaptive antennas and fading compensation through MRC, the decision signal for the first stage of MPIC will have the strongest desired part and least interference compared to any MPIC available. As can be appreciated, the first stage BER of the present receiver will be the lowest. Then, this low BER will result in a more accurate MAI regeneration, which will further cause a lower BER for the next stage and any subsequent stages.

Abstract: The present invention relates to an adaptive algorithm and device for the same, for calculating a weight vector to be applied to an adaptive array antenna system, suggesting an adaptive algorithm suitable for calculating an autocovariance matrix of signal vectors of signals received from antennas before despreading in a known channel code, and an autocovariance matrix of signal vectors of signals received from antennas after being despread in the known channel code. Particularly, the calculation is carried out with the autocovariance matrix of the signal vector before the despread divided into diagonal components and non-diagonal components.

Abstract: A single-user detection method operates to reduce the effects of interference in multi-user detection systems. Based upon a number of received user codes, a receiver defines a frame of symbols containing at least one window. A symbol amplitude of a single-user in a multi-user system is approximated over the window of the frame and a perturbative correction value is calculated based upon a correlation or decorrelation matrix, which is determined by the delay spread of the signals. An estimation of the symbol amplitude of the single-user signal is calculated over one or a number of windows of the frame. The single-user signal is detected when the symbol amplitudes of the entire signal within the frame has been calculated.

Abstract: Briefly, exemplary embodiments of the invention may provide devices and methods to provide precise and/or low phase-noise quadrature oscillation signals. A quadrature oscillator in accordance with an exemplary embodiment of the invention may include, for example, a phase-shift generator to provide a phase-shift of substantially &pgr;/2 radians to an oscillation signal between a first oscillation tank, which provides substantially no phase-shift, and a second oscillation tank.

Abstract: Embodiments of the present invention provide a method, apparatus and system for path searching, including computing a set of slope-normalized operator values corresponding to a set of respective signal samples.

Abstract: Estimation of a signal to interference ratio in a cellular communications system is described wherein an estimate for interference is the weighted sum of individual interference estimates along each of a plurality of multi-paths, weighted according to estimates of the signal power, likewise along each of a plurality of multi-paths.

Abstract: A system and method for reducing multi-path distortion of an M-ary communication signal is implemented with M×N parallel processors, a multi-path estimator, a metric selector and a decision processor. Parallel processors process each combination of possible signal symbols M and hypothesized guard times N, the output of the processors are supplied to the multi-path estimator which estimates the actual multi-path distortion of the transmitted symbol. The metric selector selects the processors with a guard time Gn most closely approximating the estimate from the multi-path estimator. The selected outputs are used in a decision processor to determine the transmitted symbols. The selected outputs are low passed filtered.

Abstract: Embodiments of the present invention relate generally to receivers. One embodiment relates to a digital FM receiver having multiple sensors (e.g. antennas). In one embodiment, the digital receiver includes a baseband unit having a channel processing unit. In one embodiment, the channel processing unit is capable of calculating or estimating a phase difference between the incoming signals prior to combining them. One embodiment uses phase estimation method for diversity combining the signals while another embodiment utlizes a hybrid phase lock loop method. Also, some embodiments of the present invention provide for echo-cancelling after diversity combining. An alternate embodiment of the channel processing unit utilizes a space-time unit to diversity combine and provide echo cancelling for the incoming signals.

Abstract: A RFI canceller, for use in a subscriber line system using multi-carrier modulation, measures a RFI disturbance in carriers falling within a band of frequencies causing the RFI. The RFI ingress into carriers outside the band of frequencies is estimated, and an error correcting signal derived from the estimation of the RFI ingress is subtracted from a received signal. The subscriber line system may be a VDSL system and the multi-carrier modulation may be DMT. The RFI canceller includes a demodulator for demodulating an incoming data stream to provide a first parallel data stream. A parallel to serial convertor converts the first parallel data stream to a first serial data stream. A digital to analogue convertor converts the first serial data stream to a first analogue signal. An analogue RFI canceller circuit combines the analogue signal with an analogue error correcting signal, to produce a second analogue signal.

Abstract: A receiver (10) for a wireless telecommunications system that provides relatively wideband signal processing of received signals without increased signal distortion so that multiple received signals can be simultaneously processed. The receiver (10) includes a specialized LNA (16), frequency down-converter (18) and ADC (20) to perform the wideband signal processing while maintaining receiver performance. The frequency down-converter (18) employs a suitable mixer (28), BPA (32), attenuator (34), and transformer (36) that are tuned to provide the desired frequency down-conversion and amplitude control over the desired wideband. The down-converter devices are selected depending on the particular performance criteria of the ADC (20). A specialized digital channelizer (22) is included in the receiver (10) that receives the digital signal from the ADC (20), and separates the signals into the multiple channels.