47 results about "Receiver diversity" patented technology

In high data rate communication applications where digital data information is error-corrected coded and interleaved and transmitted with spectral limitations over fading dispersive channels, a method and receiver is described that incorporates channel estimation and decision-feedback equalization. Channel estimation is accomplished within a receiver time block with locally generated reference symbol sequences. The parameters of the decision-feedback equalizer (DFE) are computed directly from the channel estimates. The DFE is an optimum finite length realization that includes effects from spectrum control filtering, a space-time block coder (STBC) on multiple transmit antennas, multiple receiver diversity signals, and the fading dispersive channel. The DFE includes a matched filter, forward filter, backward filter, and detector. A symbol combiner within the matched filter produces a P+1 dimensional signal that provides ideal cancellation of P intersymbol interferers in the forward filter. When P is selected to meet an intersymbol interference (ISI) criterion, all desired signal energy is collected and all ISI can be ideally cancelled. The DFE processes received signals within the receiver time block to produce information symbol estimates that are subsequently deinterleaved and error-correction decoded to recover the transmitted digital data information. Deinterleaving over multiple receiver time blocks further compensates for channel estimation variations from block to block. Additionally the STBC and DFE are used in a quadruple angle diversity technique requiring only a single antenna at each terminal of a troposcatter link to provide performance approaching that of a nonfading satellite link.

A communication system transmits and receives a plurality of spread-spectrum signals having differences in at least one diversity parameter. The signals are highly correlated when their diversity parameters are similar, and the signals are uncorrelated when at least one diversity parameter is different Any combination of a transmitter, a receiver, and a communication channel may diversity-encode the signals to effect differences in their diversity parameters. A receiver diversity-decoder compensates for differences in a diversity-parameter of at least one received signal to make the signal highly correlated with at least one other received signal. A correlator combines at least two of the received signals to recover an embedded information signal. The communication system enables the use of true-noise signals for spreading information signals, provides simplified receiver designs, and enables antenna arrays to spatially process spread-spectrum signals.

A diversity receiver system applying diversity to improve reception of coded data in presence of fading of the broadcast signal. The communication system includes a diversity receiver system receiving the coded data modulated broadcast signal from a transmission channel. The diversity receiver system has a signal acquisition device for evaluation of the signal characteristics of copies of the coded data modulated broadcast signal, extracting the coded data, control signals, and locking signals from the copies of the coded data. A diversity circuit selects one of the copies of the coded data modulated broadcast signals. An error evaluation circuit evaluates the coded data signal for errors and provides an error signal to the diversity circuit indicating an error state of the selected data, wherein the diversity circuit selects a second copy of the coded data modulated broadcast signal.

A token-based receiver diversity processing is described. In one embodiment, a receiver diversity comprises repeaters receiving wirelessly transmitted packets from a mobile station, and one of the repeaters forwarding packets of the wirelessly transmitted packets to a switch if the one repeater is currently assigned to forward packets from the mobile station based on an indicator assigned prior to the wirelessly transmitted packets being sent.

Receiver diversity in a wireless device is controlled in response to operating conditions, transmission requirements, and control settings. The control of diversity reduces power consumption by enabling receive diversity on given conditions. Operating conditions, transmission requirements, and control settings are used separately or used in conjunction to determine whether benefits of multi-antenna receive diversity, such as higher link capacity, higher data throughput, lower transmit power, and lower error rate, warrant the higher power cost of the diversity.

Wireless receivers are described for receiving signals from a transmitter. A receiver can include a plurality of antennas each for receiving a version of a signal via a different propagation channel and providing that version to a respective input. Signal processing means can be included and configured to operate diversity processing of a supplied number of said inputs for use in performing detection of said signal. The receiver can include channel parameter estimation means, configured to estimate one or more channel parameters on the propagation channels. The receiver can also include selection means configured to select only a subset of said inputs to implement a specific dimensionality of the receiver diversity processing, in dependence on the one or more channel parameters indicative of channel conditions on said propagation channels. The diversity processing can be linear or non-linear. Related methods and software implementations and computer program products are also described.