Abstract: A method is for communicating by tracking time varying channels in a multiple access packet based communication network. Each packet includes a preamble portion including a data symbol, and a data portion including data symbols. The method may include initializing a channel estimate reference from an initial channel estimate based upon the data symbol in a preamble portion of a received packet, and updating the channel estimate reference based upon a channel estimate of a current data symbol and a previously received data symbol from the data symbols in a data portion of the received packet. The method may also include repeating the updating upon receipt of a subsequent data symbol from the data symbols in the data portion of the received packet.

Abstract: Methods and apparatus are described for improving receiver performance in a multicarrier communication network in which an encoded symbol (250) is transmitted over a transmission channel (20) in the communications system. A model of the transmission channel (20) is estimated (718, 760), said model characterizing an effect of intercarrier interference on at least one carrier in the multicarrier system. The received symbol (250) is decoded (720, 762) using the estimated model to remove a predicted effect of intercarrier interference. A pre-processor (40) is also described for operation in conjunction with a communications receiver (30) in the network. The pre-processor (40) includes a channel estimator (42) operable to estimate at least one feature of the communication channel based on a received signal. The pre-processor (40) modifies the received signal dependent on the at least one estimated feature and provides the modified signal to the communications receiver (30).

Abstract: Methods and apparatus are described for processing data in a wireless communication network. Iterative estimation techniques are used to enable tracking of time-varying communication channels. A signal is transmitted over a channel in the network, the signal comprising a sequence of symbols carried on a plurality of sub-carriers. Boot-up estimator (304) estimates, in a time domain, parameters of a model of the channel based on the received signal. A domain converter (206) transforms at least one of the estimated parameters from the time domain to provide at least one transformed parameter in a second domain. An equalizer (210) and decoder (212) determine estimates of symbols from the received signal using the at least one transformed parameter, and tracking estimator (314) updates the estimated model parameters during reception of the signal using at least one estimated symbol.

Abstract: Methods and apparatus are described for processing data in a wireless communication network. Iterative estimation techniques are used to enable tracking of time-varying communication channels. A signal is transmitted over a channel in the network, the signal comprising a sequence of symbols carried on a plurality of sub-carriers. Boot-up estimator estimates, in a time domain, parameters of a model of the channel based on the received signal. A domain converter transforms at least one of the estimated parameters from the time domain to provide at least one transformed parameter in a second domain. An equalizer and decoder determine estimates of symbols from the received signal using the at least one transformed parameter, and tracking estimator updates the estimated model parameters during reception of the signal using at least one estimated symbol.

Abstract: A data processing device (100, 300) is described forming part of a receiver for a multicarrier communications system. The data processing device is configured to process at least one observed symbol to generate an information bit estimate for the symbol, and includes a channel prediction stage configured to receive an observed symbol and at least one feedback signal representing an estimate of a transmitted symbol and to generate a channel prediction. At least one initial processing stream (104) is configured to process the observed symbol on the basis of a channel prediction calculated at a respective time by the channel prediction stage and to output a signal representing an estimate of a transmitted symbol corresponding to the observed symbol for feed back into the channel prediction stage.

Abstract: The present application discloses a number of inventions directed to method(s), apparatus and/or networks and systems adapted to track time varying channels, adapted to synchronize packets arriving at a receiver, adapted to correlate a received signal, adapted to manage digital resources, adapted to receive a signal and/or adapted to enable communication in a wireless packet based communications network.

Abstract: Described herein is a method and system for estimating a time-varying multipath communication channel. The system comprises a receiver for receiving a signal comprising a data packet transmitted over the multipath communication channel. The system also comprises a frequency-domain channel estimator that generates a frequency-domain channel estimate based on the received signal. The system further comprises a time-domain channel modeller that receives the frequency-domain channel estimate and generates an estimate of parameters in a time-domain model of the multipath communication channel. The model characterises the multipath communication channel as a delay line with a plurality of taps, each tap having tap parameters defining a delay, a Doppler and a gain for the tap. The tap parameters are constant over the data packet.

Abstract: 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 equalization, iterative joint channel estimation and detection/decoding, iterative space-time processing, iterative multi user interference cancellation and iterative demodulation.

Abstract: A method and system are described for estimating an environment surrounding a wireless communication system, the environment including at least one in hector that inflects transmitted signals. An observation generator receives an input signal transmitted from a transmitter to a receiver via a wireless communication channel and also receives system state information pertaining to at least one of the receiver, the transmitter and the inflector. An observation processor uses observations from the observation generator to estimate at least one property of the inflector based on the received input signal and the system state information.

Abstract: The present application discloses a number of inventions directed to method(s), apparatus and/or networks and systems adapted to track time varying channels, adapted to synchronise packets arriving at a receiver, adapted to correlate a received signal, adapted to manage digital resources, adapted to receive a signal and/or adapted to enable communication in a wireless packet based communications network.

Abstract: The present application discloses a number of inventions directed to method(s), apparatus and/or networks and systems adapted to track time varying channels, adapted to synchronize packets arriving at a receiver, adapted to correlate a received signal, adapted to manage digital resources, adapted to receive a signal and/or adapted to enable communication in a wireless packet based communications network.

Abstract: 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.

Abstract: 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.

Abstract: 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.