Northern Telecom Limited

Zinwave Limited

Axxcelera Broadband Wireless, Inc.

Nortel Networks Corporation

Cambridge Broadband Limited

Cambridge Broadband Networks Limited

Benedict Russell Freeman

John David Porter

Walter Charles Vester

Emiliano Mezzarobba

Zafer Boz

Andrew Robert Bell

Graham Ronald Howe

Trevor Gears

Robin Paul Rickard

A distributed antenna system (DAS) includes a wideband antenna device having respective transmit and receive antennas disposed in a single package and arranged to provide mutual isolation so that in use noise from the transmit antenna is isolated from the receive antenna, whereby reception is possible at the same frequency as transmission.

Flexible distributed antenna system using a wideband antenna device

A distributed antenna system (DAS) including a wide band antenna device having respective transmit and receive antennas disposed in a single package and arranged to provide mutual isolation so that in use noise from the transmit antenna is isolated from the transmit antenna, whereby reception is possible at the same frequency as transmission.

Flexible distributed antenna system using a wide band antenna device

A packet switched communications system and method for transmitting synchronous data from a source module () to a terminating module () over a network comprising plurality of modules () interconnected via transmission links (). Each module operates with a clock of nominal frequency that is not synchronized with the clocks of the other module(s) and has a single input and one or more outputs. The method includes determining the phase difference between the input clock and the output clock of each module, and transmitting the phase difference to the terminating module () in the network. The received accumulated phase difference at the terminating module () is used to lock the output clock at the terminating module to the input clock at the source module.

Synchronization in a communication system

A dynamic channel allocation method and system for use in a wireless network operates by monitoring at least the allocated channel allocated to a particular network node to generate one or more channel metrics relating to radio conditions on the channel. The metrics generated are Received signal power, signal to noise ratio of transmissions on the network and long-term mean square of the equaliser error used in each terminal. The generated metrics are communicated back to the cell access point or the network control server over a signalling channel, and a new frequency is allocated to the cell if it is determined from the metrics that the presently allocated channel is suffering interference. The signalling channel is preferably an ATM VPI/VCI pair, such that signalling messages are transmitted as ATM cells which can be communicated across the wireless channel using the sane signalling frame as is used for payload cells.

Control signaling and dynamic channel allocation in a wireless network

Control signalling and dynamic channel allocation in a wireless network

A decode apparatus for decoding a plurality of encoded messages received over a noisy transmission link, eg., a satellite link or a radio telecoms link comprises a demodulator for demodulating analogue signals to produce a digitized bit stream; an analyzer comprising a received signal strength indicator; a carrier to noise ratio measurement means; a look up table for reading data describing an optimized number of decode iterations; an array of turbo code decoders, each having an associated local storage buffer; and a scheduler means for scheduling demodulated message packets to each of the plurality of decoder processors, depending upon an estimated optimum number of decode operations required for each message packet. Allocation of the message packets to the plurality of decode processors is made such as to optimize overall utilization of the decode processors. The number of decode processors required for a system is estimated from a statistical analysis of the noise and optimum number of decode iterations required to decode an incoming time division multiplex bit stream having time division messages which differ in noise ratio, and hence require different processing powers for decoding, between successive time division multiplex messages.

Statistically multiplexed turbo code decoder

This invention relates to telecommunications systems. In a subscriber loop carrying high speed data signals, noise cancellation is achieved by a data signal demodulator having first and second inputs 81,82, arranged to receive differential data signal and local field RFI input signals respectively. A feedback signal of the demodulator is sampled, processed, vector modulated and then combined with the local field RFI input signal of the demodulator. The combined signal is summed with the differential input signal to thereby reduce interference coupled with the first input.

Interference reduction in telecommunication systems

This invention relates to telecommunications systems. The present invention provides a system and method operable to the cancel interference from digital subscriber line systems. A data signal demodulator having first and second inputs arranged to receive differential data signals and local field RFI signals respectively, wherein a digital adaptive notch filter is formed by DSP means which locates an interferer in the differential signal by adapting its bandwidth and center frequency by adaptation means and wherein the center frequency and bandwidth of the notch filter are used to generate a bandpass filter centered on the interferer and of approximate bandwidth to the interferer; whose output, after processing forms a feedback signal which is sampled, processed, weighted and then combined with the local field RFI input signal of the demodulator, which combined signal is summed with the differential input signal to thereby cancel interference coupled onto the first input.

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Cambridge, United Kingdom

Benedict Russell Freeman