A broadcast signal receiver includes a demodulator configured to perform Orthogonal Frequency Division Multiplexing (OFDM) demodulation on a received broadcast signal; a frame parser configured to derive service data by parsing a signal frame of the received broadcast signal based on a number of carriers of the signal frame; a decoder configured to perform error correction on the service data; and an output processor configured to receive the service data and output a data stream, wherein the number of carriers of the signal frame is determined by equation: NoC=NoC_maxk*, the NoC being the number of carriers, the NoC_max being maximum number of carriers, the k being a reducing coefficient and the being a control unit value, wherein the k ranges from 0 to 4 and the is 96 for 8K Fast Fourier Transform (FFT), 192 for 16K FFT, 384 for 32K FFT.

A method for a receiving side processing a signal in a wireless communication system according to the present invention may comprise the steps of: receiving, from a transmitting side, information for the length, in a band where the receiving side is allocated, of a band pass filter to be applied to a transmission signal of the transmitting side and the length of the greatest band pass filter applied to a time interval identical to the transmission signal; and on the basis of the information for the length of a band pass filter to be applied to a transmission signal of the transmitting side and the length of the greatest band pass filter applied to a time interval identical to the transmission signal, setting an N Fast Fourier Transform (FFT) window starting point for detecting the transmission signal.

The present disclosure provides a symbol synchronization method and apparatus. By means of the symbol synchronization method and apparatus, a timing location is adjusted outside an adaptive loop. In addition, the adaptive loop proceeds to according to an original function of the adaptive loop. That is, the timing location is stabilized to an initial symbol-synchronization location, and the timing location is then further corrected and adjusted. Therefore, impact of an error of a timing location on symbol synchronization is eliminated by correcting the timing location, and positioning accuracy of a symbol-synchronization location is improved.

A method and wireless communication device for tracking frequencies of transmitted burst signals. The method includes receiving a burst signal, determining a quality of the burst signal and a carrier frequency of the burst signal, demodulating the burst signal based upon the determined carrier frequency, determining a frequency offset of the burst signal based on the determined carrier frequency, and when the quality of the burst signal exceeds a threshold, calculating a drift window based on the determined frequency offset.

In an example of wireless communications, an access point may send a downlink frame to multiple stations. The downlink frame may include information indicative of a cyclic prefix length to be utilized by the stations. In response, some or all of the stations may transmit their respective uplink frames to the access point. A cyclic prefix for a portion of each respective uplink frame may have a cyclic prefix length corresponding to the information included in the downlink frame. The downlink frame may be, for example, a beacon frame or a trigger frame. A trigger frame may allocate resources for uplink orthogonal frequency division multiple access (OFDMA) transmission. Other methods, apparatus, and computer-readable media are also disclosed.

The object of the present invention is to reduce the number of complex multiplications in an ICI reduction processing and to reduce the influence of characteristic degradation due to a quantization bit limitation of a digital signal processing. A receiver includes an extended CP addition unit (102) that receives radio signals through a plurality of paths and compensates for a symbol lost within a Fourier transform window to received signals received through the plurality of paths; and FFTs (104-1 and 104-2) each of which performs, in a range of the Fourier transform window, Fourier transform on the received signal with a lost symbol added.

Methods, systems, and devices for wireless communication are described. Wireless stations (STAs) may have traffic to exchange between one another. Through establishing a direct connection with another STA, communications may flow directly from one STA to the other STA, without occupying resources of the network at the access point (AP). This may make the network more efficient, as the AP may direct those unused resources to other communication needs. When establishing a direct connection between STAs, the STAs may be unable or have difficulty determining a signal strength because different signals may be based on different transmission powers. In some examples, it may be beneficial to use a ranging frame, such as a fine timing measurement (FTM) frame, for determining a signal strength between two STAs.

A broadcast signal transmitter is provided that includes an input formatter, a Forward Error Correction (FEC) encoder, a constellation mapper, a time interleaver, a framer and a waveform generator. The input formatter input processes input data to output Physical Layer Pipe (PLP) data. The FEC encoder performs FEC encoding on the PLP data. The constellation mapper performs constellation mapping on the PLP data. The time interleaver is configured to time interleave the PLP data. The framer is configured to generate a signal frame comprising the PLP data. The waveform generator is configured to generate a transmission broadcast signal comprising the signal frame. A number of carriers of the signal frame is determined by the equation: NoC=NoC_maxk*, wherein NoC is the number of carriers, NoC_max is a maximum number of carriers, k is a reducing coefficient, and is a control unit value.

A digital beam-forming network for an array antenna having N>1 antenna ports, to be associated to respective antenna elements, and M1 beam ports (BP), corresponding to respective antenna beams. The digital beam-forming network comprises a plurality of complex weighting elements interconnected through summing nodes. At least one of the complex weighting elements is connected to either two antenna ports, to be associated with respective antenna elements which are arranged symmetrically with respect to the symmetry axis, or two beam ports corresponding to respective antenna beams pointing toward directions which are symmetrical with respect to the symmetry axis, or both. The digital beam forming network can be a part of an array antenna comprising N antenna elements, N.sub.S of which are arranged according to an array pattern having a symmetry axis, N.sub.S being an even integer different from zero.

A method and apparatus are provided for performing acquisition, synchronization and cell selection within an MIMO-OFDM communication system. A coarse synchronization is performed to determine a searching window. A fine synchronization is then performed by measuring correlations between subsets of signal samples, whose first signal sample lies within the searching window, and known values. The correlations are performed in the frequency domain of the received signal. In a multiple-output OFDM system, each antenna of the OFDM transmitter has a unique known value. The known value is transmitted as pairs of consecutive pilot symbols, each pair of pilot symbols being transmitted at the same subset of sub-carrier frequencies within the OFDM frame.