Embodiments of the present invention disclose a data processing method and apparatus, and belong to the field of communications technologies. The method includes: generating a physical layer protocol data unit PPDU, where the PPDU includes a preamble field, a data field, and a middle preamble field, and the preamble in the PPDU includes information used to indicate an insertion frequency of the middle preamble in the data field in the PPDU; and sending the PPDU. The insertion frequency of the middle preamble in the data field is indicated by using a specified field in the preamble. In this way, in different scenarios, the middle preamble may be inserted into the data field at different frequency, thereby reducing overheads of an inserted pilot and improving data transmission performance.

A method for transmitting a multi-carrier signal implementing an OQAM-type modulation, formed of a temporal succession of symbols including data elements modulating a carrier frequency of the signal. A carrier frequency modulated by one of the data elements is called a carrier, wherein a set of carriers is allocated to a transmitter unit. The method includes inserting a sequence of pilots specific to the transmitter unit at a given time into the multi-carrier signal on the allocated set of carriers. The sequence of pilots includes: a sequence of non-zero complex values, inserted on odd or even carriers, alternating with zero values, inserted on the other carriers, respectively even or odd-numbered; non-zero complex values of the sequence of pilots, their frequency transforms and inverse frequency transforms being with a constant envelope; and and a sequence of zero values modulating the carriers of the set of carriers allocated at the following time.

The present invention is designed to provide highly efficient small cell radio access. In a communication system to include a macro station (30), a local station (20), and a mobile terminal apparatus (10), the local station (20) generates measurement signals that are used in measurements in the mobile terminal apparatus (10) based on user an identifier or a user group identifier, and transmits this signal to the mobile terminal apparatus (10). The mobile terminal apparatus (10) receives the measurement signals transmitted from the local station (20) and carries out with measurements with respect to the measurement signals based on the user identifier or the user group identifier.

The apparatus for transmitting broadcast signals, the apparatus comprises an encoder for encoding service data corresponding to each of a plurality of data transmission path, wherein each of the data transmission path carries at least one service component, a frame builder for building at least one signal frame including the encoded service data, a modulator for modulating the at least one signal frame by an OFDM (Orthogonal Frequency Division Multiplex) scheme, a transmitter for transmitting the broadcast signals carrying the at least one modulated signal frame, wherein each of the at least one signal frame includes a preamble having signaling data, wherein the signaling data includes size of FFT, information of whether the signal frame including EAC message or not and information relating to the service data of the signal frame.

An apparatus and method for generating a broadcast signal frame for signaling a time interleaving mode are disclosed. An apparatus for generating broadcast signal frame according to an embodiment of the present invention includes a time interleaver configured to generate a time-interleaved signal by performing time interleaving on a BICM output signal; and a frame builder configured to generate a broadcast signal frame including a preamble for signaling a time interleaving mode corresponding to the time interleaver for each of physical layer pipes (PLPs).

A method and apparatus are provided for reducing the number of pilot symbols within a MIMO-OFDM communication system, and for improving channel estimation within such a system. For each transmitting antenna in an OFDM transmitter, pilot symbols are encoded so as to be unique to the transmitting antenna. The encoded pilot symbols are then inserted into an OFDM frame to form a diamond lattice, the diamond lattices for the different transmitting antennae using the same frequencies but being offset from each other by a single symbol in the time domain. At the OFDM receiver, a channel response is estimated for a symbol central to each diamond of the diamond lattice using a two-dimensional interpolation. The estimated channel responses are smoothed in the frequency domain. The channel responses of remaining symbols are then estimated by interpolation in the frequency domain.

The present specification, provides a method for generating a low peak to average power ratio (PAPR) sequence in a wireless communication system. Specifically, the present specification relates to a method for generating a low PAPR sequence in a wireless communication system, the method comprising the steps of: generating a sequence of length-6 having a symbol as each element of the sequence; and generating the low PAPR sequence on the basis of the sequence of length-6.

This application provides a reference signal generation method, a reference signal detection method, and a communications apparatus, so that a terminal device or a network device can generate a reference signal by using a pseudo-random sequence initial factor c.sub.init provided in embodiments of this application. Compared with a solution in the current technology, the generation manner can support a relatively large quantity of reference signal sequences, to better meet requirements of a plurality of 5G scenarios. The method may include: obtaining a reference signal sequence based on a pseudo-random sequence initial factor c.sub.init; and mapping the sequence to one or more OFDM symbols, where the pseudo-random sequence initial factor c.sub.init is related to a parameter d, d=max(log.sub.2(n.sub.ID,max+1)−10,0) or d=max(log.sub.2(n.sub.ID,max+1)−12,0), max represents that a larger value is selected from two values, and n.sub.ID,max represents a maximum value of a reference signal sequence ID.

A multi-carrier cellular wireless network (400) employs base stations (404) that transmit two different groups of pilot subcarriers: (1) cell-specific pilot subcarriers, which are used by a receiver to extract information unique to each individual cell (402), and (2) common pilots subcarriers, which are designed to possess a set of characteristics common to all the base stations (404) of the system. The design criteria and transmission formats of the cell-specific and common pilot subcarriers are specified to enable a receiver to perform different system functions. The methods and processes can be extended to other systems, such as those with multiple antennas in an individual sector and those where some subcarriers bear common network/system information.

The present invention relates to orthogonal frequency-division multiplexing (OFDM) communication systems with four transmit antennas and one or more receive antennas, and in particular to methods for inserting scattered pilots (SPs) into the transmit signals of such OFDM systems, for estimating channel properties on the basis of the scattered pilots, a multi-antenna OFDM transmitter, and an OFDM receiver. In this context, it is the particular approach of the present invention to keep the same SP pattern like in the single-transmitter case, to partition the pilots into as many subsets as there are transmitters (transmit antennas), and to interleave these subsets both in time and in frequency. In this manner, the granularity of pilots of the same subset is reduced. This offers increased flexibility in designing the scattered pilot patterns and greater accuracy of the estimated channel properties.