The apparatus may be a user equipment (UE). The apparatus receives a transmission of at least one of a plurality of first synchronization signals. The apparatus receives at least one repeat transmission of the at least one of the plurality of first synchronization signals. In an aspect, the transmission and the at least one repeat transmission are received in a same synchronization signal block.

According to an aspect of the disclosure, a base station may convey the parameter information to the UE based on selection of particular resources to be used for transmission of synchronization signals, where the selected resources correspond to the particular parameter information. The UE may blindly detect the synchronization signals on various candidate resources and determine the parameter information based on the resources where the synchronization signals are detected. The apparatus may be a base station. In an aspect, the base station determines parameter information of one or more parameters. The base station selects, based on the parameter information, synchronization resources from a plurality of candidate resources for transmission of one or more synchronization signals, where the selected synchronization resources correspond to the parameter information. The base station transmits the one or more synchronization signals using the selected synchronization resources.

Aspects of the present disclosure relate to methods and apparatus for location encoding for secondary synchronization signals (SSS) to convey additional information, such as a current symbol number. According to aspects, a method is provided herein for wireless communications that may be performed, for example, by a base station (BS). The method generally includes selecting frequency resources to use for transmitting synchronization signals in a symbol of a frame, wherein the frequency resources are selected based on a mapping of frequency resources to a location of the symbol within the frame; and transmitting synchronization signals to at least one user equipment (UE) according to the mapping. As a result, the UE may receive synchronization signals, determine a location of the current symbol in a frame based on the mapping, and synchronize to the BS based on the determined location of the current symbol. Numerous other aspects are provided.

Provided is a method and apparatus for receiving a reference signal. A wireless user device may determine, based on a synchronization signal (SS) block index and based on an index associated with a time interval, an initialization value associated with a reference signal for a physical broadcast channel (PBCH). The wireless user device may receive, based on the initialization value and based on a frequency domain shift value, the reference signal via at least one resource element (RE). The reference signal may be mapped, based on the frequency domain shift value, to the at least one RE. The wireless user device may receive the PBCH.

In one embodiment, an apparatus includes: a radio frequency (RF) front end circuit to receive and downconvert a RF signal to a second frequency signal, the RF signal comprising an orthogonal frequency division multiplexing (OFDM) transmission; a digitizer coupled to the RF front end circuit to digitize the second frequency signal to a digital signal; and a baseband processor coupled to the digitizer to process the digital signal. The baseband circuit comprises a first circuit having a first plurality of correlators having an irregular comb structure, each of the first plurality of correlators associated with a carrier frequency offset and to calculate a first correlation on a first portion of a preamble of the OFDM transmission.

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.

Methods, apparatuses, and systems for wireless communications are described. Uplink signals may be time aligned based on different synchronization signals for different carrier groups. A base station may send, to a wireless device, a time alignment command. Based on the time alignment command, the wireless device may send an uplink signal.

Disclosed herein are a method and an apparatus for transmitting an uplink control channel for a high speed terminal. In a method for transmitting an uplink control channel in a mobile communication system, an uplink control channel signal is generated depending on at least one resource index received from a base station and the uplink control channel signal is transmitted to the base station through a resource block corresponding to the resource index. A location where the uplink control channel signal is allocated is changed depending on the resource index.

Disclosed is a method by which a first terminal receives a signal in a wireless communication system. Particularly, the method comprises the steps of: receiving a synchronization signal for device-to-device communication from a second terminal; obtaining synchronization based on the synchronization signal; receiving a boundary signal for the device-to-device communication from the second terminal; and receiving a control signal or a data signal using the device-to-device communication based on the boundary signal, wherein the synchronization signal is transmitted by using a part of one symbol.

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.