Neul Ltd.

Huawei Technologies Co., Limited

Kabushiki Kaisha Toshiba

Cambridge Consultants Limited

3com Technologies

Robert William Young

Brian Martin Gaffney

Andrew James Shields

Nigel Lawrence Bragg

Tong Ji

Yiling Wu

Guangwei Yu

James Digby Collier

Richard Mark Stevenson

Timothy John Newton

James Andrew Bangham

Zhiliang Yuan

Anthony John Bennett

William Webb

Benedict Peters

Brian Gaffney

The present disclosure relates to the field of wireless communications technologies, relates to a signal sending device, a signal receiving device, a symbol timing synchronization method, and a system, and resolves a problem that complexity of symbol timing synchronization performed by a terminal with relatively low crystal oscillator accuracy is high. In a receiving device, a receiving module receives a synchronization signal including a first signal and a second signal. The first signal includes N1 generalized ZC sequences, and the second signal includes N2 generalized ZC sequences. The second signal is used to distinguish different cells or different cell groups. There are at least two generalized ZC sequences with different root indexes in (N1+N2) generalized ZC sequences. A processing module performs a first sliding correlation operation and a second sliding correlation operation on the synchronization signal, and performs symbol timing synchronization according to a relationship between a sliding correlation peak generated when a sliding correlation is performed on the N1 generalized ZC sequences and a sliding correlation peak generated when a sliding correlation is performed on the N2 generalized ZC sequences. This has relatively low implementation complexity, compared with an existing method in which grid search should be performed multiple times to compensate for a relatively large phase rotation.

Signal sending device, signal receiving device, symbol timing synchronization method, and system

The present invention relates to the field of wireless communications technologies. In a receiving device, a receiving module receives a synchronization signal including a first signal and a second signal. The first signal includes N1 generalized ZC sequences, and the second signal includes N2 generalized ZC sequences. The second signal is used to distinguish different cells or different cell groups. There are at least two generalized ZC sequences with different root indexes in (N1+N2) generalized ZC sequences. A processing module performs a first sliding correlation operation and a second sliding correlation operation on the synchronization signal, and performs symbol timing synchronization according to a relationship between a sliding correlation peak generated when a sliding correlation is performed on the N1 generalized ZC sequences and a sliding correlation peak generated when a sliding correlation is performed on the N2 generalized ZC sequences.

A communication device configured to operate in accordance with a first communication protocol and to align itself with one or more communications transmitted in accordance with that protocol by identifying a communication transmitted in accordance with a second communication protocol that is not intended for the communication device, deriving alignment information from the identified communication and configuring itself to receive a communication transmitted in accordance with the first communication protocol in dependence on the alignment information.

Device and method for deriving alignment information

A method for allocating bandwidth to communication according to a first communication protocol, the method comprising identifying bandwidth that is allocated to a communication channel for communication according to a second communication protocol and which forms a guard band of the communication channel and allocating the identified bandwidth to communication according to the first communication protocol, said allocation being performed non-uniformly across the identified bandwidth such that an allocation of a first portion of the identified bandwidth, which is located closer to a communication according to the second communication protocol than a second portion of the identified bandwidth, is constrained to a greater extent than an allocation of the second portion of the identified bandwidth.

Communication bandwidth

A frequency error embodied in a series of values is determined by processing each of two or more selected values with another value in the series, each other value being spaced from its respective selected value by a first spacing, to generate processed values that all comprise substantially the same phase component; combining the processed values to generate a combined value that comprises substantially the same phase component as the processed values; repeating the processing and combining with the same selected values but a second spacing, different from the first spacing, to generate a combined value comprising a different phase component from the combined value generated using the first spacing, reflecting the frequency error; and determining the frequency error in dependence on the combined values generated using the first and second spacings.

Method and apparatus for estimating frequency errors

A communication system comprising a base station and two or more terminals configured for communicating with the base station by means of a communications protocol, wherein: the communications protocol operates in a frequency band to which unlicensed access is permitted; and the terminals are configured for unattended operation with the base station.

Inter-device communication in a machine to machine communication network

A method for synchronising a receiving device with a transmitting device in a wireless communication network comprising forming a synchronisation sequence that has a frequency spectrum comprising peaks at multiple discrete fundamental frequencies, a signal power of the synchronisation sequence being concentrated at those frequencies, and transmitting said synchronisation sequence from the transmitting device to the receiving device.

Synchronization mechanism

A communication device for communicating via a wireless network that is permitted to operate only in communication channels that are not designated for use by another network, the communication device being configured to determine that it is permitted to use a communication channel and use only a part of the bandwidth of that communication channel in dependence on an activity associated with a device operating outside of the wireless network.

Channel bandwidth

A method for estimating an unwanted component that a receiver introduces into a signal at a known frequency, the method comprising applying a frequency offset to a signal, which comprises a wanted component at the known frequency, to form an offset signal having a frequency spectrum in which the wanted component is not positioned at the known frequency, processing the offset signal in the receiver and estimating a component positioned at the known frequency in the frequency spectrum of the processed signal.

DC offset compensation

According to one embodiment, a quantum information system includes a source of time dependent entangled photons and an indicating unit. The indicating unit indicates the entangled state of the entangled photons based on the emission time of one or more of the entangled photons.

Quantum information system

An optical data retrieval system configured to retrieve data from a data storage medium, including: a source of n path-entangled photons, where n is an integer of at least 2; a detector system configured to determine if n photons have been received; and a mechanism to direct photons from the source to the data storage medium and to the detector system.

Optical retrieval system, data storage system, data storage medium and method of optical retrieval and data storage

A decision feedback encoder comprising an analog-to-digital converter for converting an input signal into digital signals representing decision levels, digital processing circuits responsive to signals from the converter for providing a succession of symbol values and a set of coefficients, digital-to-analog converters for converting the coefficients into corresponding analog values and analog circuits for forming a sum of the products of each of the symbol values and a respective one of said analog values to provide a feedback signal for the reduction of inter-symbol interference in the input signal.

Growing community of inventors

Cambridge, United Kingdom

Robert William Young