954 results about "Communications receiver" patented technology

The present invention is directed to the selective provision of interference canceled signal streams to demodulating fingers in a communication receiver. According to the present invention, potential interferer signal paths are identified. Signal streams having one or more potential interferer signals removed or canceled are created, and a correlation is performed to determine whether the strength of a desired signal path increased as a result. If the correlation indicates that the strength of a desired signal path was increased by the signal cancellation, the interference canceled signal stream is provided to the demodulation finger assigned to track the desired signal path. If the correlation determines that the strength of the desired signal path did not increase as a result of performing interference cancellation, the raw or a different interference canceled signal stream is provided to the demodulation finger.

Techniques for calculating the system characteristic of the adaptive filtering used for equalization and echo-suppression in a digital communications receiver, such as one used for receiving over-the-air broadcast digital television signal, are described. In these techniques, the system characteristic of the adaptive filtering is calculated from the discrete Fourier transform of successive portions of the input signal supplied to the adaptive filtering and from the discrete Fourier transform of corresponding portions of the transmitted signal, as estimated in the receiver. Receivers for implementing these techniques in various ways are also disclosed.

In the context of array sensors such as radar, sonar, and communications receiver arrays, the present invention exploits the geometry phase components of radiated wavefronts associated with the signals of interest in order to reduce the bandwidth requirements for DOA and beamforming processing. Additionally, geometry phase is exploited in order to effectively increase the resolution of an array without changing the size of its physical footprint or the number of array elements. Other embodiments of the invention include the use of virtual array elements for increase in effective array size.

The invention regards a system and method for using a handheld programming device to configure a lighting control system wirelessly. In one embodiment, at least one device configured with a processing section is installed in the lighting control system. A communications receiver that is operable to receive a signal from the handheld programming device is also installed in the lighting control system, wherein the signal includes an instruction for configuring the lighting control system. Further, the signal is wirelessly sent from the handheld programming device to the communications receiver, and the instruction is transmitted from the communications receiver to a device in the system. The instruction functions to configure the lighting control system.

In the context of array sensors such as radar, sonar, and communications receiver arrays, the present invention exploits the geometry phase components of radiated wavefronts associated with the signals of interest in order to reduce the bandwidth requirements for DOA and beamforming processing. Additionally, geometry phase is exploited in order to effectively increase the resolution of an array without changing the size of its physical footprint. Other embodiments of the invention include the use of virtual array elements for increase in effective array size.

A vehicle navigation system for use with a traffic information broadcast system which transmits traffic data relating to primary road segments and a communication system which transmits traffic data relating to road segments in a local geographic area. A broadcast receiver receives the broadcast traffic data from the broadcast system and stores the received data. A communication transmitter, when activated, transmits a data request to the communication system. A communication receiver receives the local traffic data from the communication system in response to the data request while a processor displays traffic information on a display screen corresponding to the received broadcast traffic data and the received local traffic data. The local traffic data includes both traffic information relating to local road segments as well as non-traffic temporal events, such as weather, and time-related events which affect traffic flow. A database of historic traffic flow for the road segments is periodically updated to reflect new traffic data.

A novel and useful whitening matched filter (WMF) for use in a communications receiver. The WMF is constructed by cascading a matched filter and a noise-whitening filter. The response of the matched filter is derived from the time reversed complex conjugate of the channel impulse response. The whitening filter is derived by extracting the minimum phase portion of the mixed phase channel impulse response using homomorphic deconvolution. The whitening filter is implemented using either an FIR or IIR filter adapted to process the data received before and after the training sequence using a minimum phase system in a direction in time opposite to that of the direction of corresponding data sample processing performed by the equalizer.

A vehicle navigation system for use with a traffic information broadcast system which transmits traffic data relating to primary road segments and a communication system which transmits traffic data relating to road segments in a local geographic area. A broadcast receiver receives the broadcast traffic data from the broadcast system and stores the received data. A communication transmitter, when activated, transmits a data request to the communication system. A communication receiver receives the local traffic data from the communication system in response to the data request while a processor displays traffic information on a display screen corresponding to the received broadcast traffic data and the received local traffic data. The local traffic data includes both traffic information relating to local road segments as well as non-traffic temporal events, such as weather, and time-related events which affect traffic flow.

A receiver for mobile communication includes a wireless scheme parameter storing unit (23) configured to store a plurality of characteristics of multiple wireless schemes, a wireless scheme estimation unit (22) configured to estimate one of the characteristics of a currently used wireless scheme from a received signal and select one of the wireless schemes corresponding to the estimated characteristic from the wireless scheme parameter storing unit, and a demodulator (24) configured to demodulate the received signal based on the selected wireless scheme.

A method for testing a semiconductor device with a multi-gigabit communications receiver includes combining a data output from a high-speed communications transmitter with a perturbation signal generated by automatic test equipment. The combined signal data signal including jitter and low voltage swings is input to the communications receiver port under test. The automatic test equipment determines the bit error rate of the parallel data output from the receiver port under test. This test method is appropriate for semiconductor devices with multiple transceiver ports.

A mobile communication base station determines the oncoming direction of a radio wave with a simple arrangement and transmits a narrow angle beam in this direction. Received signals from a pair of wide angle beam antennae 21-1 and 21-2 having an equal configuration and a common orientation and which are located close to each other are fed to a direction finder receiver 22 and a communication receiver 15. By utilizing the fact that the both received signals have a coincident amplitude, a phase difference between the received signals is detected. The oncoming direction of the received radio wave (or the direction of a mobile station) is determined on the basis of the phase difference. A beam switcher 12 is controlled so as to connect a transmitter 13 to a narrow angle beam antenna (one of 11-1 to 11-4) which is directed in the oncoming direction thus determined.

A wireless optical transceiver system which includes a passive optical antenna coupled by optical fiber to an active electronics module. The transceiver system receives and transmits light beams from / to the atmosphere,.and thereby communicates optically with a second optical transceiver. Receivers, transmitters, repeaters, switches, routers, etc., may be similarly organized, i.e. by coupling one or more passive optical antennas and an active electronics module with fiber-optic cable. Furthermore, various network toplogies and organizations may be arranged using one or more of the fiber-coupled transceivers, receivers, transmitters, repeaters, switches, routers, etc. Such components are admirably suited for use in various network configurations such as broadcast networks, point-to-multipoint networks, etc due to their low cost, ease of installation and antenna sighting, modularity, and upgradability. An optical router for establishing wireless channels to a number of subscribers may be configured based on demodulation and remodulation of light beams, or alternatively by redirecting light beams by adjustable deflections mirrors. A communications network infrastructure based on atmospheric light beam propagation is contemplated.

A test signal generator at a transmitter station and a facsimile generator at a receiver station go through an acquisition and tracking process which aligns the two signals so that a logical processor can compute the frequency transfer function of the entire propagation path for use in an adaptive, concurrently sent communication signal. The frequency transfer function is conveyed back to the transmit end via a control channel permitting an adaptivity function at the transmit end to influence subsequent selection of communication parameters, among which are typically transmitted data rate, selection of modulation, selection of forward error correcting coding, and selection of frequency band for transmission. The same measurement is conveyed to an adaptivity function at the receive end for use in the communications receiver to select demodulator variables such as gain control, and equalization of amplitude and phase, versus frequency. The adaptivity function also permits interspersing of reverse-direction communications over the same frequency bands in a time-share mode between forward-direction and reverse-direction communication with the measurement signals having to be transmitted in only one direction. An alternate embodiment invention of this type is described which is additionally useful for mobile communications channels. Another variation embodiment is described for pure propagation measurements only, absent conveyance of end-user information.

A novel and useful apparatus for and method of I / Q gain mismatch compensation for use in a communications receiver. The invention is operative to calculate an estimate of the I / Q gain mismatch. Each input sample is subsequently multiplied by the inverse of the estimate to generate compensated samples. The training sequence portion of the uncompensated input samples is used to generate the I / Q gain mismatch estimate. In accordance with the present invention, the H matrix used in calculating the gain mismatch estimate is pre-calculated for several channel lengths and stored in memory. An estimate of the channel is generated which provides the channel length and the location in the input sample buffer of the first training sequence sample to be used in calculating the gain mismatch estimate. The channel length is used to determine the number of training sequence samples to be used and to select one of the previously calculated H matrices.

A test signal generator at a transmitter station and a facsimile generator at a receiver station go through an acquisition and tracking process which aligns the two signals, removing errors in the time base of generation, the frequency offset of generation and the time of arrival, so that a logical processor can compute the frequency transfer function of the entire propagation path for use in an adaptive, concurrently sent communication signal. The frequency transfer function is conveyed back to the transmit end via a control channel permitting an adaptivity function at the transmit end to influence subsequent selection of communication parameters, among which are typically transmitted data rate, selection of modulation, selection of forward error correcting coding, and selection of frequency band for transmission. The same measurement is conveyed to an adaptivity function at the receive end for use in the communications receiver to select demodulator variables such as gain control, and equalization of amplitude and phase, versus frequency. The adaptivity function also permits interspersing of reverse-direction communications over the same frequency bands in a time-share mode between forward-direction and reverse-direction communication with the measurement signals having to be transmitted in only one direction. An alternate embodiment invention of this type is described which is additionally useful for mobile communications channels. Another variation embodiment is described for pure propagation measurements only, absent conveyance of end-user information.

The present invention relates to improved multiple access communications. In one form, the invention relates to an improved signal processing method and apparatus for an iterative method of determining the reception of a signal in a multi user packet based wireless OFDM (Orthogonal Frequency Division Multiplexing) communication system. In other forms the present invention provides recursive filtering for joint iterative decoding in a variety of systems and functions such as linear multiple access channel decoders, iterative equalisation, iterative joint channel estimation and detection / decoding, iterative space-time processing, iterative multi user interference cancellation and iterative demodulation. In one particular form the present invention provides an iterative decoding circuit for a wireless multiuser communications receiver comprising a first signal processing means for receiving at least one received signal, said first signal processing means comprising at least two linear iterative filters such that the first linear iterative filter provides an estimate of a selected received signal to an estimated signal output and a second linear iterative filter provides estimates of at least one other received signal, delayed by one iteration cycle, to an input of said first linear iterative filter, a second signal processing means for receiving the estimated signal output of the first linear iterative filter and providing a further received signal estimate to the input of the first signal processing means in a succeeding iteration cycle of the decoding circuit.

A mobile communication base station determines the oncoming direction of a radio wave with a simple arrangement and transmits a narrow angle beam in this direction. Received signals from a pair of wide angle beam antennae 21 - 1 and 21 - 2 having an equal configuration and a common orientation and which are located close to each other are fed to a direction finder receiver 22 and a communication receiver 15 . By utilizing the fact that the both received signals have a coincident amplitude, a phase difference between the received signals is detected. The oncoming direction of the received radio wave (or the direction of a mobile station) is determined on the basis of the phase difference. A beam switcher 12 is controlled so as to connect a transmitter 13 to a narrow angle beam antenna (one of 11 - 1 to 11 - 4 ) which is directed in the oncoming direction thus determined.

A method to secure file origination, access and updates between a sender and a receiver is provided. The method includes generating a transmit payload to transmit to the receiver, generating an authentication data structure to transmit to the receiver, generating a permissions credential to transmit to the receiver, creating a scrambled message by combining and transforming the transmit payload, the authentication data structure, and the permissions credential, using a pre-determined scheme, transmitting the scrambled message to the receiver, receiving the scrambled message, applying the pre-determined scheme to recover a received payload, a received authentication data structure, and a received permissions credential, from the scrambled message, evaluating the received authentication data structure, and if authentication fails, ignoring the received payload, evaluating the received permissions credential, and if the received permissions credentials are insufficient, ignoring the received payload, and performing steps (a.)-(k.) for subsequent communications between the sender and the receiver.

An apparatus for and method of generating normalized soft decision information output from an inner decoder (i.e. equalizer) in a communications receiver. The invention is operative to normalize the soft decision information before it enters a soft outer decoder. The normalization is performed using a noise power estimate that is dynamically calculated in response to changing noise statistics on the channel. The normalized soft decision output is then applied to the soft outer decoder thus realizing maximum performance therefrom. The noise power estimate is derived from the training sequence and / or the data portion of the received signal. Both types of estimates are calculated. A binary or smoothly weighted average is calculated using both types of estimates. The weighting factor is determined based on one or more performance metrics, such as the Signal to Noise Ratio (SNR).

A telecommunication device comprising a base unit and a cordless handset, wherein said telecommunication device is operable in a plurality of modes of operation. The base unit includes: (1) a ring signal detection module communicatively coupled to a telephone network; (2) a voice communication channel also communicatively coupled to said telephone network; (3) a wireless communication transmitter module; (4) a wireless receiver module; and (5) a controller for executing program instructions. The cordless handset includes: (1) a ringer module; (2) an ear piece; (3) a microphone; (4) a talk request command input device; (5) a wireless communication transmitter; and (6) a wireless communication receiver. The modes of operation include a talk request mode of operation, wherein (1) a ringing signal is received at said base unit; (2) said base unit transmits a wireless signal to said cordless handset; (3) said cordless handset receives said wireless signal; from said base, and initiates said local ringer module; (4) said base unit counts a predetermined number of rings; (5) said base unit initiates an off-hook condition in response to detection of a predetermined number of rings; (6) an outgoing message (OGM) is played at said base unit; (7) actuation of said talk request command input device is detected; (8) said base unit receives a wireless talk request signal (TRS) from said cordless handset, initiates an OGM end detection means, and continues to play said OGM; and (9) upon detection of end of said OGM by said OGM end detection means, said base unit inhibits the start of an incoming message (ICM) means and connects the calling party with the called party at said cordless handset.

Embodiments of the invention may provide for reducing interference in the front-end of a communications receiver. The cancellation circuitry may be utilized in conjunction with a preliminary rejection filter for improved rejection of out-of-band interference from other radio services or circuitry. The cancellation circuit may be placed in parallel with the preliminary rejection filter and may enhance suppression at the interference frequency by matching the gain and phase of the preliminary rejection filter prior to subtracting the matched signal from the preliminary rejection filter output. The cancellation circuit need not necessary know beforehand the characteristics of the preliminary rejection filter, the interference source, or the coupling mechanism, as it may adapt to unknown or varying interferers by adapting the matching gain and phase values based on the output of the preliminary rejection filter at tap points occurring both before and after application of the cancellation signal.

A filter system comprising three or more filters, each having different passbands, and an impedance adjusting network coupled between a filter system ports and each of the ports of at least two of the filters to adjust the port impedances of the filters coupled to the network. The adjusted port impedance of each filter at a frequency representative of at least one of the other filters coupled to the network is at a non-loading level. In one embodiment, the filter system is configured for use in a wireless communication receiver and / or handset.

A wireless communication receiver, such as the receiver included in a wireless communication transceiver implemented in a base station or in a mobile station of a wireless communication network, includes a parametric G-RAKE receiver circuit and a method that compute parametric scaling parameters on a per transmission interval basis. In one embodiment, measured impairment correlations are obtained for an individual transmission slot and used to estimate instantaneous values of the scaling parameters. One or both of those instantaneous values are then constrained according to one or more defined limits. In other embodiments, multiple transmission slots are used to increase the number of measurements available to estimate the scaling parameters, with parameter constraining optionally applied. Further embodiments use iterative methods and / or solve for one parameter, and use the results to obtain the other parameter(s). One or more of these embodiments can be improved through the use of error correction / detection information.

A test signal generator at a transmitter station and a facsimile generator at a receiver station go through an acquisition and tracking process which aligns the two signals so that a logical processor can compute the frequency transfer function of the entire propagation path for use in an adaptive, concurrently sent communication signal. The frequency transfer function is conveyed back to the transmit end via a control channel permitting an adaptivity function at the transmit end to influence subsequent selection of communication parameters, among which are typically transmitted data rate, selection of modulation, selection of forward error correcting coding, and selection of frequency band for transmission. The same measurement is conveyed to an adaptivity function at the receive end for use in the communications receiver to select demodulator variables such as gain control, and equalization of amplitude and phase, versus frequency. The adaptivity function also permits interspersing of reverse-direction communications over the same frequency bands in a time-share mode between forward-direction and reverse-direction communication with the measurement signals having to be transmitted in only one direction. An alternate embodiment invention of this type is described which is additionally useful for mobile communications channels. Another variation embodiment is described for pure propagation measurements only, absent conveyance of end-user information.

The invention regards a system and method for using a handheld programming device to configure a lighting control system wirelessly. In one embodiment, at least one device configured with a processing section is installed in the lighting control system. A communications receiver that is operable to receive a signal from the handheld programming device is also installed in the lighting control system, wherein the signal includes an instruction for configuring the lighting control system. Further, the signal is wirelessly sent from the handheld programming device to the communications receiver, and the instruction is transmitted from the communications receiver to a device in the system. The instruction functions to configure the lighting control system.