Accordingly, embodiments herein disclose a method for signal synchronization in orthogonal frequency-division multiplexing (OFDM) based Narrow Band-Internet of Thing (NB-IoT) system. The method includes generating a New Radio-Narrowband Primary Synchronization Signal (NR-NPSS). Further, the method includes mapping each Zadoff-chu sequence of 14 Zadoff-chu sequences of the NR-NPSS to resource elements of each OFDM symbol of 14 OFDM symbols in an NR-NPSS subframe. Further, the method includes transmitting the NR-NPSS subframe comprising the mapped NR-NPSS to at least one User Equipment (UE) (200), receiving the NR-NPSS subframe comprising the transmitted NR-NPSS by a base station (100), generating a reference NR-NPSS, mapping each of the 14 Zadoff-chu sequences of the NR-NPSS to resource elements of each OFDM symbol of 14 OFDM symbols in an NR-NPSS subframe, and detecting the NR-NPSS from the received NR-NPSS subframe using the reference NR-NPSS to obtain the time and frequency synchronization in the NB-IoT system.

Systems and methods for transmitting data using various Modulation on Zeros schemes are described. In many embodiments, a communication system is utilized that includes a transmitter having a modulator that modulates a plurality of information bits to encode the bits in the zeros of the z-transform of a discrete-time baseband signal. In addition, the communication system includes a receiver having a decoder configured to decode a plurality of bits of information from the samples of a received signal by: determining a plurality of zeros of a z-transform of a received discrete-time baseband signal based upon samples from a received continuous-time signal, identifying zeros that encode the plurality of information bits, and outputting a plurality of decoded information bits based upon the identified zeros.

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.

An operation method of a first communication node in a communication system, according to an exemplary embodiment of the present disclosure for achieving the above-described objective, may comprise: transitioning to a down-clocking state; performing a monitoring operation in the down-clocking state; detecting reception of a first packet transmitted from a second communication node providing a service to the first communication node; identifying a first preamble included in the first packet; performing analysis on the first preamble; and based on a result of the analysis on the first preamble, determining whether to maintain the down-clocking state or transition to a full-clocking state.

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.

A packet detecting method includes receiving the wireless signal, generating a local characteristic sequence, acquiring a first cross-correlation result between the wireless signal and the local characteristic sequence, determining if a packet format of the wireless signal is a target packet format according to the first correlation result, generating at least one interference characteristic sequence according to the local characteristic sequence, a signal sampling frequency, and at least one working frequency difference, acquiring a second cross-correlation result between the wireless signal and the at least one interference characteristic sequence, and detecting a center frequency of the wireless signal for determining if a packet of the wireless signal is transmitted through a target channel according to the first correlation result and the second correlation result. The at least one interference characteristic sequence corresponds to at least one interference frequency.

Monitoring an operational characteristic of a data communication device within a network includes sampling an operational characteristic of the data communication device at a fine-grain sample rate over a first sampling interval to produce fine-grain samples of the operational characteristic of the data communication device, training a machine learning algorithm using the fine-grain samples of the operational characteristic of the data communication device, the fine-grain sample rate, and a coarse-grain sample rate that is less than the fine-grain sample rate, sampling the operational characteristic of the data communication device at the coarse-grain sample rate over a second sampling interval to produce coarse-grain samples of the operational characteristic of the data communication device, and using the machine learning algorithm to process the coarse-grain samples of the operational characteristic of the data communication device to produce accuracy-enhanced samples of the operational characteristic of the data communication device.

Methods, systems and device for achieving synchronization in an orthogonal time frequency space (OTFS) signal receiver are described. An exemplary signal reception technique includes receiving an OTFS modulated wireless signal comprising pilot signal transmissions interspersed with data transmissions, calculating autocorrelation of the wireless signal using the wireless signal and a delayed version of the wireless signal that is delayed by a pre-determined delay, thereby generating an autocorrelation output, processing the autocorrelation filter through a moving average filter to produce a fine timing signal. Another exemplary signal reception technique includes receiving an OTFS modulated wireless signal comprising pilot signal transmissions interspersed with data transmissions, performing an initial automatic gain correction of the received OTFS wireless signal by peak detection and using clipping information, performing coarse automatic gain correction on results of a received and initial automatic gain control (AGC)-corrected signal.

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.