Provided are a multipath separation method and device, and a storage medium. The multipath separation method includes: extracting frequency domain response characteristics of received reference signals in at least two different frequency bands; for each of the at least two different frequency bands, constructing a Toeplitz matrix; combining Toeplitz matrixes corresponding to the at least two different frequency bands; performing singular value decomposition on the synthesized Toeplitz matrix; determining a signal space matrix and a noise space matrix according to the decomposed matrix; constructing a plurality of frequency domain response vectors according to frequency domain response characteristics of local signals having different delays and are the same as the received reference signals; and comparing a first preset threshold with inner products between each of the plurality of frequency domain response vectors and the noise space matrix respectively, and determining a delay corresponding to each of a plurality of frequency domain response vectors in which inner products satisfy the first preset threshold to be a delay of one path in the multipath.

Disclosed are a method and an apparatus for estimating a frequency offset in a wireless communication system. The method for estimating a frequency offset of the present disclosure comprises the steps of: acquiring a first symbol from which a cyclic prefix (CP) symbol of a received symbol is removed; acquiring a second symbol from which data having a length corresponding to a length of CP is removed at an end opposite to the end in which the CP is present in the received symbol; and estimating the frequency offset by using the first symbol and the second symbol.

Methods, systems, and devices for wireless communications are described. A device (e.g., a base station or a user equipment (UE)) may identify a sequence length corresponding to a number of resource blocks, and select a modulation scheme based on the sequence length. The device may select, from a set of sequences associated with the modulation scheme, a sequence having the sequence length. In some examples, the set of sequences may include at least one of a set of time domain phase shift keying computer-generated sequences or a set of frequency domain phase shift keying computer-generated sequences. The device may generate a reference signal for a data transmission based on the sequence and transmit the reference signal within the number of resource blocks.

A method for determining and compensating for residual phase noise in a 5G NR DL signal includes converting a block of 5G NR DL time domain signal samples into a block of frequency domain samples for one OFDM data symbol and equalizing and combining the frequency domain samples that fall in an outermost sample accumulation region of each quadrant to form a first composite sample for each quadrant, selecting a signal constellation point belonging to one of the four outermost constellation point decision region as a reference constellation point, rotating at least some of the first composite samples so that the first composite samples are in the same quadrant as the reference constellation point, combining the rotated first composite samples to produce a second composite sample, calculating a phase error between the second composite sample and the reference constellation point, applying phase correction corresponding to the phase error to all subcarriers of the OFDM data symbol, and generating output data from the phase-error-corrected OFDM symbol.

A method for determining coarse carrier phase and frequency offsets of an initial block of received M-QAM symbols includes creating a grid of discrete candidate phase offset values and for each candidate value: applying the candidate value to each symbol, applying a respective hard decision to each applied symbol, and computing a figure of merit based thereon. The candidate value having the best figure of merit is selected as an initial phase offset estimate. An initial frequency offset estimate is computed using the symbols updated with the initial phase offset estimate, their respective hard decisions, and an approximation of the complex exponential function. To track carrier phase and frequency offsets associated with a series of symbol blocks, for each symbol of a current block, set a binary trust weight based on comparison of a computed parameter with a threshold and use the binary trust weights to compute a phase offset error and a frequency offset error for the current block.

Some demonstrative embodiments include apparatuses, devices, systems and methods of communicating a PPDU including a training field. For example, an Enhanced Directional Multi-Gigabit (DMG) (EDMG) wireless communication station may be configured to determine one or more Orthogonal Frequency Division Multiplexing (OFDM) Training (TRN) sequences in a frequency domain based on a count of one or more 2.16 Gigahertz (GHz) channels in a channel bandwidth for transmission of an EDMG PPDU including a TRN field; generate one or more OFDM TRN waveforms in a time domain based on the one or more OFDM TRN sequences, respectively, and based on an OFDM TRN mapping matrix, which is based on a count of the one or more transmit chains; and transmit an OFDM mode transmission of the EDMG PPDU over the channel bandwidth, the OFDM mode transmission comprising transmission of the TRN field based on the one or more OFDM TRN waveforms.

A data sending apparatus includes a processor and a transceiver. The processor is configured to generate K first frequency-domain data streams, wherein a k.sup.th first frequency-domain data stream of the K first frequency-domain data streams is determined by performing preprocessing on a k.sup.th first modulated data stream, and the preprocessing includes at least a Fourier transform, a cyclic extension, or a phase rotation. The processor is further configured to map the K first frequency-domain data streams to frequency-domain resources to generate a time-domain symbol, and the transceiver is configured to send the time-domain symbol. A length of the k.sup.th first frequency-domain data stream of the K first frequency-domain data streams is N.sub.k, and a length of the k.sup.th first modulated data stream is M.sub.k. K is a positive integer greater than 1, N.sub.k and M.sub.k are positive integers, and k is an integer k=0, 1, . . . , K−1.

In one embodiment, a device in a low-power and lossy network (LLN) makes, based on a temperature measurement, a first adjustment to a frequency for a wireless channel used by the device to communicate with one or more neighboring devices in the LLN. The device receives, via the wireless channel, a packet from one of the neighboring devices that indicates a transmit frequency for the packet. The device calculates a frequency offset based on a difference between the transmit frequency for the packet and the adjusted frequency for the wireless channel. The device makes, based on the calculated frequency offset, a second adjustment to the frequency for the wireless channel used by the device to communicate with the one or more neighboring devices in the LLN.

A profile optimizing method is provided for a transmission of active subcarriers over a channel to user devices. The method includes steps of (i) obtaining a symbol mapping architecture for the set of profiles, (ii) calculating, from the symbol mapping architecture, a plurality of mapping orders for the set of profiles different from the logical order, (iii) determining, from the calculated plurality of mapping orders, a particular mapping order having a higher spectral efficiency than the logical order, (iv) reordering the respective codewords of the set of profiles to correspond to the particular mapping order, (v) re-mapping the symbol mapping architecture to a number of symbols corresponding to the reordered codewords, and (vi) transmitting the symbols to the population of user devices. The symbol mapping architecture includes a codeword for each profile of the set of profiles, and maps the codewords to a different number by logical order.

An HE-LTF transmission method is provided, including: determining, based on a total number N.sub.STS of space-time streams, a number N.sub.HELTF of OFDM symbols included in an HE-LTF field; determining a HE-LTF sequence in frequency domain according to a transmission bandwidth and a mode of the HE-LTF field, where the HE-LTF sequence in frequency domain includes but is not limited to a mode of the HE-LTF field sequence that is in a 1× mode and that is mentioned in implementations; and sending a time-domain signal according to the number N.sub.HELTF of OFDM symbols and the determined HE-LTF sequence in frequency domain. In the foregoing solution, a PAPR value is relatively low.