Abstract: In the various embodiments, decoders, methods, systems and devices exploit state information associated with transmitted packets to facilitate decoding operations. Specifically, in at least some embodiments, packets are received by a receiver. If the packet is unable to be decoded because of corruption, state information associated with that packet is buffered at the receiver and used for subsequent decoding. A retransmitted packet is then received, checked for corruption and, if not corrupted, is decoded leveraging the previously-buffered state information associated with the corrupted packet. In an event that one or more retransmitted packets are corrupted, this process can be repeated a number of times.

Abstract: In the various embodiments, decoders, methods, systems and devices exploit state information associated with transmitted packets to facilitate decoding operations. Specifically, in at least some embodiments, packets are received by a receiver. If the packet is unable to be decoded because of corruption, state information associated with that packet is buffered at the receiver and used for subsequent decoding. A retransmitted packet is then received, checked for corruption and, if not corrupted, is decoded leveraging the previously-buffered state information associated with the corrupted packet. In an event that one or more retransmitted packets are corrupted, this process can be repeated a number of times.

Abstract: Various decoders, methods, systems, and devices are provided that selectively employ a decoding operation as a function of the size of a received data packet. In at least some embodiments, a first decoding operation is performed on data packets within a first size range. A second decoding operation(s), different from the first, is (are) performed on data packets within a second size range. In at least some embodiments, the first decoding operation is a sliding-window decoding operation and the second decoding operation is one other than a sliding-window decoding operation.

Abstract: The present invention relates to an apparatus for estimating and compensating a carrier frequency offset, and a data receiving method in a receiver of a wireless communication system. The apparatus correlates a received signal with a signal delayed by a predetermined period of the received signal in a correlation window, wherein the correlation window is set based on a Cycle Prefix (CP) and a preamble repetition length from a predetermined position, converts the correlated value into a phase value, compensates a phase of the converted result according to preamble segment numbers, and estimates an initial carrier frequency offset value.

Abstract: A method of detecting a frame boundary of a received signal in a digital communication system, the method including: generating a delayed signal by delaying the received signal by a predetermined period; calculating a correlation value by correlating the received signal with the delayed signal for a predetermined correlation length in a time domain; and determining a timing index corresponding to a maximum value, as a frame boundary index, from a plurality of correlation values which are obtained by repeating the calculation. According to an embodiment of the present invention, a correlation calculation in a time domain is performed without oversampling, in a limited length including a cyclic prefix. Accordingly, accuracy of frame boundary detection may be improved and complexity of hardware and software may also be reduced.

Abstract: An apparatus for searching for a cell in a mobile communication system, including: a preamble sequence storage unit storing preamble sequences each of which corresponds to one preamble index, and a cell searching unit correlating a received signal and the stored preamble sequences in a time domain and identifying the preamble index corresponding to the received signal. The cell searching apparatus correlates a received signal and stored preamble sequences in a time domain. The apparatus employs binary quantization of preamble sequences to reduce calculation and memory size. Also, the stored preamble sequences are phase pre-rotated according to a segment number, to prevent from a burden of frequency offset correction caused by three different hypotheses. Accordingly, a complexity of the cell searching apparatus is reduced and cell searching performance becomes more accurate.

Abstract: A likelihood metric calculation method including: estimating a channel of a received signal and generating a channel estimate; compensating a channel of the received signal according to the channel estimate; calculating a region variable according to the channel estimate; and comparing the region variable and a magnitude of the compensated received signal and calculating a likelihood metric of the received signal according to a result of the comparison.

Abstract: A method of selecting an antenna for ranging detection in an orthogonal frequency division multiple access system, the method including: receiving at least one ranging symbol from the antenna; and determining whether to select the antenna, by correlation computing the received ranging symbol in a time domain.

Abstract: A method of detecting a frame boundary of a received signal in a digital communication system, the method including: generating a delayed signal by delaying the received signal by a predetermined period; calculating a correlation value by correlating the received signal with the delayed signal for a predetermined correlation length in a time domain; and determining a timing index corresponding to a maximum value, as a frame boundary index, from a plurality of correlation values which are obtained by repeating the calculation. According to an embodiment of the present invention, a correlation calculation in a time domain is performed without oversampling, in a limited length including a cyclic prefix. Accordingly, accuracy of frame boundary detection may be improved and complexity of hardware and software may also be reduced.

Abstract: An apparatus for searching for a cell in a mobile communication system, including: a preamble sequence storage unit storing preamble sequences each of which corresponds to one preamble index, and a cell searching unit correlating a received signal and the stored preamble sequences in a time domain and identifying the preamble index corresponding to the received signal. The cell searching apparatus correlates a received signal and stored preamble sequences in a time domain. The apparatus employs binary quantization of preamble sequences to reduce calculation and memory size. Also, the stored preamble sequences are phase pre-rotated according to a segment number, to prevent from a burden of frequency offset correction caused by three different hypotheses. Accordingly, a complexity of the cell searching apparatus is reduced and cell searching performance becomes more accurate.

Abstract: The present invention relates to an apparatus for estimating and compensating a carrier frequency offset, and a data receiving method in a receiver of a wireless communication system. The apparatus correlates a received signal with a signal delayed by a predetermined period of the received signal in a correlation window, wherein the correlation window is set based on a Cycle Prefix (CP) and a preamble repetition length from a predetermined position, converts the correlated value into a phase value, compensates a phase of the converted result according to preamble segment numbers, and estimates an initial carrier frequency offset value.

Abstract: A likelihood metric calculation method including: estimating a channel of a received signal and generating a channel estimate; compensating a channel of the received signal according to the channel estimate; calculating a region variable according to the channel estimate; and comparing the region variable and a magnitude of the compensated received signal and calculating a likelihood metric of the received signal according to a result of the comparison.