Patent
Synchronization and cell search methods and apparatus for wireless communications
Tony Ottosson,Eric Wang +1 more
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TLDR
In this paper, a synchronization signal is determined from the interference cancellation of a component of the synchronization detection signal associated with a known synchronization signal to produce an interference-canceled synchronisation detection signal.Abstract:
A received communications signal is correlated with a common synchronization code to produce a synchronization detection signal. A component of the synchronization detection signal associated with a known synchronization signal is canceled from the synchronization detection signal to produce an interference-canceled synchronization detection signal. Timing of a synchronization signal is determined from the interference-canceled synchronization detection signal. According to one aspect, interference cancellation is achieved by generating a correlation of an estimated received known synchronization signal with the common synchronization code, canceling the correlation of the estimated received known synchronization signal with the common synchronization code from the synchronization detection signal to produce the interference-canceled synchronization detection signal. Timing of a synchronization signal may then be determined by accumulating the interference-canceled synchronization detection signal over a time interval, detecting a peak in the accumulated interference-canceled synchronization detection signal, and determining timing of a synchronization signal from the detected peak. According to another aspect, interference cancellation is achieved by accumulating the synchronization detection signal over a time interval, identifying a peak in the accumulated synchronization detection signal not associated with a known synchronization signal, and determining timing of a synchronization signal from the identified peak. Related terminal apparatus are also discussed.read more
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References
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Journal ArticleDOI
Wideband DS-CDMA for next-generation mobile communications systems
TL;DR: In this article, a wideband wireless access based on direct sequence code division multiple access aimed at third-generation mobile communications systems is reviewed, and the radio link performance evaluated by computer simulation is also presented.
Journal ArticleDOI
UMTS/IMT-2000 based on wideband CDMA
TL;DR: UTRA based on W-CDMA can now be regarded as a mature technology, ready to provide the basis for UMTS/IMT-2000, and has flexible support of mixed services, variable-rate services, and an efficient packet mode.
Patent
Pilot interference cancellation for a coherent wireless code division multiple access receiver
TL;DR: In this article, a Code-Division Multiple Access (CDMA) receiver removes the pilot signal from the received signal, defined by its multipath parameters (amplitudes, phase shift and delays) and its signature sequence.
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Coherent random access channel in a spread-spectrum communication system and method
TL;DR: In this paper, reference symbols are inserted into a stream of access channel message data symbols and appended to a synchronization message to form a reference coded access channel transmission, and a channel response is determined from the correlation peak and revised based on estimates derived from the stream of reference samples.
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Mobile station and cell selecting method for code division multiplex access mobile communication.
TL;DR: In this paper, the received signal of a control channel of each cell is despread by each spreading code in a correlation detector, and the received level of the despread output in a window, including its peak, is measured in a level measuring part and an interference signal level outside the window is also measured.