Disclosed methods include transmitting an OFDM signal including a succession of frames spaced apart by a set of training symbols that are symmetric in time and each formed by a plurality of even-frequency sub-carriers, spaced by odd frequency zeros. The OFDM signal is received and sampled and timing metrics are determined. Local maximums, or peaks of the timing metrics are detected, and from the peaks a coarse time offset is determined. A correlation metric, at sample indexes within a region determined by the coarse time offset, is applied and, based on a peak, an estimated time offset is generated. A correlation metric of the estimated time offset is determined and, based on the correlation metric, an estimated frequency offset is generated.

A fading assessment unit 34 assesses the degree of fading of a received radio wave. An SNR calculation unit 33 calculates an SNR value of a signal based on the radio wave. A communication mode determination unit 35 determines the communication mode of communication from a transmission side of the radio wave on the basis of the result of the assessment by the fading assessment unit 34 and the SNR value calculated by the SNR calculation unit 33.

This application provides a pilot transmission method, including: determining, by a first terminal device, a target first pilot and a target second pilot group corresponding to the target first pilot, where the target first pilot is used by a network device to perform terminal device detection, and the target second pilot group includes at least two second pilots; and sending, by the first terminal device, the target first pilot and the target second pilot group to the network device in a time unit, where each second pilot in the target second pilot group is repeatedly sent on at least two symbols of the time unit, and the target second pilot group is used by the network device to perform frequency offset estimation.

Provided are a control apparatus, device and method for a wireless communication system, a signal processing apparatus and method for a mobile terminal, a mobile terminal and a wireless communication system. The control apparatus comprises: a control circuit, wherein the control circuit is configured to make a plurality of the wireless communication devices send, to a mobile terminal, a plurality of synchronous sequence signals which are different from each other. According to the control apparatus, device and method, the signal processing apparatus and method, the mobile terminal and the wireless communication system in the present disclosure, the influence of a large-carrier frequency offset on the performance of a timing synchronization system can be effectively suppressed and eliminated.

Fourier transform is performed on a reception signal to obtain a first calculation value. Fourier transform is performed on a known signal to obtain a second calculation value. The first calculation value is divided by the second calculation value to obtain a third calculation value. Inverse Fourier transform is performed on the third calculation value to obtain a fourth calculation value. A maximum value of an amplitude of the fourth calculation value and a sample point at which the maximum value is obtained are detected. The position of the known signal in the reception signal is detected from the sample point at which the maximum value is obtained.

The present invention discloses a signal processing method and apparatus, and pertains to the field of communications technologies. The apparatus includes: a processor and a memory. The method includes: setting each sampling point signal on an orthogonal frequency division multiplexing OFDM symbol, and obtaining an input signal; calculating a constraint matrix according to a frequency selective fading channel characteristic; and calculating an output signal according to the sampling point signal, the input signal, and the constraint matrix. The present invention resolves a problem that frequency selective fading has an impact on transmission of the OFDM symbol, and a constraint matrix obtained according to a flat fading channel characteristic is not applicable to the OFDM symbol, thereby achieving an effect of reducing the impact of the frequency selective fading on the transmission of the OFDM symbol.

A method of synchronising a communication signal entering into a receiver. Each frame of the signal includes a learning symbol formed of N repetitions of a learning sequence. The method includes the determination of a total correlation signal by correlating the input signal with a correlation symbol formed of N repetitions of a correlation sequence corresponding to all or part of the learning sequence and duration t.sub.sc, and the determination of a partial correlation signal by correlating the input signal with the correlation sequence. A peak of the total correlation signal is identified at an instant t.sub.pct. At least one threshold is defined from the power of the peak of the total correlation signal, and the power of the partial correlation signal is compared here to the instants t.sub.pctk*t.sub.sc, with k a whole number between 0 and N1.

Disclosed methods include transmitting an OFDM signal including a succession of frames spaced apart by a set of training symbols that are symmetric in time and each formed by a plurality of even-frequency sub-carriers, spaced by odd frequency zeros. The OFDM signal is received and sampled and timing metrics are determined. Local maximums, or peaks of the timing metrics are detected, and from the peaks a coarse time offset is determined. A correlation metric, at sample indexes within a region determined by the coarse time offset, is applied and, based on a peak, an estimated time offset is generated. A correlation metric of the estimated time offset is determined and, based on the correlation metric, an estimated frequency offset is generated.

Apparatus and associated methods relate to providing robust synchronization of a Radio-Frequency (RF) communication in a severe-fading environment. A first portion of a detected RF signal is auto-correlated with a second portion of the detected RF signal. The first and second portions are time-separated by the predetermined time delay separating the first and second code-sequences. A third portion of the detected RF signal is sync-correlated with a sync-sequence so as to generate a sync-correlation signal. The third portion is of the predetermined length of the sync sequence and includes the first and second portions of the detected RF signal used to generate the auto-correlation signal. The auto-correlation signal is multiplied by the sync-correlation signal so as to generate a combined synchronization signal. A peak in the combined synchronization signal is then detected. This peak can be indicative of a synchronization time of an authorized communication.

A receiving device, user equipment, communication system and a method for processing synchronization information are provided. The receiving device comprises a synchronization information processing apparatus configured to combine synchronization information of a plurality of frequency channels based on time and frequency.