The present disclosure includes a method of performing synchronization and frequency offset estimation The method includes an input signal corresponding to a single received training sequence. Phase information and a phase index are generated by performing an auto-correlation function (ACF) on the input signal. A templet signal associated with a sample index of the input signal is generated based on at least one pre-stored look-up table (LUT), the phase index, a frequency bandwidth of the input signal, and the sample index. Power associated with the sample index is calculated by performing a matched filtering on the input signal based on the templet signal. A synchronization timing and a frequency offset for the input signal are simultaneously determined based on a result of the matched filtering.

A receiving device 100 includes a reception unit 10, a delay signal generation unit 22, a difference calculation unit 23 that calculates a phase difference between the received signal and the delay signal, a variance calculation unit 24 that calculates a variance of the phase difference within a plurality of calculation sections while sliding a set of the plurality of calculation sections which are set corresponding to a cyclic prefix group assigned to a predetermined symbol group included in the received signal, together on the time axis, a symbol detecting unit 25 that detects a position of a symbol in the symbol group on the time axis, based on the position of the minimum peak of the variance on the time axis, and a synchronization timing signal generation unit 29 that generates a synchronization timing signal, based on information on the position of the symbol on the time axis.

A method and an apparatus for obtaining timing advance value. The method comprises: receiving (S101) a time domain signal, which contains at least part of a reference signal; extracting (SI 02), from the time domain signal, a first group of signal parts including at least one signal part, and a second group of signal parts including at least one signal part, wherein the first group of signal parts do not overlap the second group of signal parts; and determining (S103) a timing advance, TA, value based on an energy of a signal part in the first group of signal parts and an energy of a signal part in the second group of signal parts, wherein the energy of the signal part is based on correlation between the signal part and the reference signal. Therefore, the TA value may be obtained based on a time domain signal.

Provided are methods of estimating a time delay and/or a frequency shift of a reference signal. Such methods include receiving a first reference signal that is generated using a first Zadoff-Chu (ZC) sequence, receiving a second reference signal that is generated using a second ZC sequence that is different than the first ZC sequence, and processing the first reference signal and the second reference signal to estimate at least one of the time delay and the frequency shift of the first reference signal and/or the second reference signal. The first ZC sequence is generated by a first root and the second ZC sequence is generated by a second root that is different than the first root.

Techniques are provided for time-domain processing of DL-PRS signals under certain conditions in which time-domain processing has a computational advantage over frequency-domain processing. Because of this, embodiments can provide positioning at a lower computational cost than positioning provided by traditional techniques utilizing only frequency-domain processing. This reduced computational cost can improve the battery life of mobile devices, ultimately resulting in a better user experience.

A method, an apparatus, a system, and a computer program product for radio synchronous status messaging between communications units in wireless communications systems. A change of status event by one or more first communications devices is detected. A message indicative of the detected change of status event is generated. The generated message is transmitted to one or more second communications devices.

Systems and methods for a non-data-aided (NDA) approach to advanced OFDM timing are provided. This approach allows for accurate OFDM symbol timing and synchronization by avoiding inter-symbol interference (ISI) in multipath environments where an earliest arriving signal may not be the strongest signal. The NDA approach may rely on generating and applying a bias correction to a combined correlation result of the multi-path signals.

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.

Systems and methods for synchronize word correlation. The methods comprise: obtaining first values that each indicate a likelihood or probability that a respective timeslot in a symbol timing window of a carrier wave is meant or expected to include energy; multiplying, by the correlator, the first values respectively by correlation coefficients to produce a plurality of products (wherein at least one of the correlation coefficients comprises a negative coefficient value); generating a correlation value by combining the products together; determining whether a synchronization word has been detected with a given amount of likelihood based on the correlation value; and causing symbol timing synchronization at a receiver when a determination is made that the synchronization word has been detected with the given amount of likelihood based on the correlation value.

Disclosed are techniques for transmitting and receiving an extended narrowband positioning reference signal (NPRS) sequence. In an aspect, a base station generates the extended NPRS sequence and transmits, to at least one user equipment (UE) over a wireless narrowband channel, the extended NPRS sequence. In an aspect, a UE receives, over the wireless narrowband channel, an NPRS of a first subset of the extended NPRS sequence and measures the NPRS of the first subset of the extended PRS sequence. In an aspect, the extended NPRS sequence may be a function of a plurality of slot numbers of a plurality of slots of a plurality of sequential radio frames and a plurality of symbol indexes of a plurality of symbols of a single physical resource block.