Embodiments can relate to transmitting or processing a demodulation reference signal; the method comprising generating a demodulation reference signal, spreading an instance of the demodulation reference signal using OCC-2 for a transmission associated antenna port 7, spreading an instance of the demodulation reference signal using OCC-4 for a transmission associated antenna port 11, and co-scheduling transmission or output of the spread instances of the demodulation reference signals.

A method performed in a preamble transmitter for transmitting a preamble sequence, the method comprising the steps of generating S11 a short sequence s(n), the short sequence having the same time duration as an OFDM symbol used for carrying data traffic in a radio access network of the preamble transmitter, constructing S12 a preamble sequence by concatenating a plurality of said short sequences in time, and transmitting S13 the constructed preamble sequence as a radio signal to a preamble receiver.

An extensible communication system is described herein. The system includes a first module for receiving a root index value and for generating a constant amplitude zero auto-correlation sequence based on the root value. The system further includes a second module for receiving a seed value and for generating a Pseudo-Noise sequence based on the seed value. The system further includes a third module for modulating the constant amplitude zero auto-correlation sequence by the Pseudo-Noise sequence and for generating a complex sequence. The system further includes a fourth module for translating the complex sequence to a time domain sequence, wherein the fourth module applies a cyclic shift to the time domain sequence to obtain a shifted time domain sequence.

A method by which a first wireless device tracks a channel in a wireless AV system, according to one embodiment of the present invention, comprises the steps of: receiving a radio signal including a first part related to a preamble and a second part related to a data block and a GI; estimating an initial channel on the basis of the preamble; estimating a residual channel on the basis of the GI, wherein a reconstruction sequence reconstructed on the basis of a Golay sequence having a predetermined length is applied to the GI; and updating a channel on the basis of first information acquired on the basis of the initial channel estimation and second information acquired on the basis of the residual channel estimation.

An extensible communication system is described herein. The system includes a first module for receiving a root index value and for generating a constant amplitude zero auto-correlation sequence based on the root value. The system further includes a second module for receiving a seed value and for generating a Pseudo-Noise sequence based on the seed value. The system further includes a third module for modulating the constant amplitude zero auto-correlation sequence by the Pseudo-Noise sequence and for generating a complex sequence. The system further includes a fourth module for translating the complex sequence to a time domain sequence, wherein the fourth module applies a cyclic shift to the time domain sequence to obtain a shifted time domain sequence.

A method of performing cell search includes receiving a primary synchronization signal (PSS) comprising a primary synchronization code (PSC) and receiving a secondary synchronization signal (SSS) comprising a first secondary synchronization code (SSC) and a second SSC, wherein the SSS includes a first SSS and a second SSS, the first SSC and the second SSC are arranged in that order in the first SSS, and the second SSC and the first SSC are arranged in that order in the second SSS. Detection performance on synchronization signals can be improved, and cell search can be performed more reliably.

Disclosed is a data transmission method in a mobile communication system. The data transmission method through a code sequence in a mobile communication system includes grouping input data streams into a plurality of blocks consisting of at least one bit so as to map each block to a corresponding signature sequence, multiplying a signature sequence stream, to which the plurality of blocks are mapped, by a specific code sequence, and transmitting the signature sequence stream multiplied by the specific code sequence to a receiver.

Narrowband Internet of Things synchronization signals are described that carry offset information. In one example an evolved NodeB (eNB) to performs operations to transmit synchronization signals for time and frequency synchronization between the eNB and user equipments (UEs) for narrowband Internet of things (NB-Iot). The operations include concatenating a plurality of short ZadoffChu (ZC) sequences each having a different root index, the ZC sequences being ordered to indicate an offset for use by a UE, generating an NB-Iot Primary Synchronization Signal (NB-PSS) using the concatenation of short ZadoffChu (ZC) sequences, and transmitting the resulting NB-PSS by the eNB in a periodic manner to the UE, wherein, the offset is identified by the order of the ZC sequences.

An extensible communication system is described herein. The system includes a first module for receiving a root index value and for generating a constant amplitude zero auto-correlation sequence based on the root value. The system further includes a second module for receiving a seed value and for generating a Pseudo-Noise sequence based on the seed value. The system further includes a third module for modulating the constant amplitude zero auto-correlation sequence by the Pseudo-Noise sequence and for generating a complex sequence. The system further includes a fourth module for translating the complex sequence to a time domain sequence, wherein the fourth module applies a cyclic shift to the time domain sequence to obtain a shifted time domain sequence.

A first endpoint generates an acoustic spread spectrum signal including a pilot sequence and a data sequence representing a token synchronized to the pilot sequence, transmits the acoustic spread spectrum signal, and records a transmit time at which the acoustic spread spectrum signal is transmitted. A receive time at which a second endpoint received the acoustic spread spectrum signal transmitted by the first endpoint is received from the second endpoint along with an indication of a second token as recovered from the received acoustic spread spectrum signal by the second endpoint. A separation distance between the first endpoint and the second endpoint is computed based on a time difference between the transmit time and the receive time. The first endpoint is paired with the second endpoint when the token matches the second token and the computed distance is less than a threshold distance.