Systems, methods, and baseband processors are provided to generate or process symbols in a synchronization subframe. In one example, a method includes selecting non-consecutive orthogonal frequency division multiplexing (OFDM) symbols in a synchronization subframe. A transmitter is instructed to transmit demodulation reference symbols (DM-RS) on identical first sets of subcarriers in respective OFDM symbols of the selected non-consecutive OFDM symbols for a Physical Broadcast Channel (PBCH) using a same transmit beam, wherein a gap between two subcarriers in a respective set of the identical first sets of subcarriers is three subcarriers. The transmitter is instructed to transmit the PBCH on identical second sets of subcarriers in respective OFDM symbols in the selected non-consecutive OFDM symbols.

A base station may determine a root for a sequence to be included in a signal to a UE. The base station may generate a generalized Chu sequence based on the root and scramble the generalized Chu sequence using a pseudorandom sequence that is common to a plurality of base stations. The base station may transmit the scrambled generalized Chu sequence to indicate the beginning of a downlink transmission. The UE may receive this scrambled generalized Chu sequence and determine if a beginning of a downlink transmission from a serving base station based on the received generalized Chu sequence and an expected generalized Chu sequence.

A signal sending and receiving method and apparatus are provided. A first signal is sent, and a sequence of the first signal is generated at least based on a first sequence and a second sequence. There are multiple manners for determining the first sequence and the second sequence. For example, the first sequence is determined at least according to start time domain location information of the first signal and current time domain location information of the first signal, and the second sequence is determined at least according to a cell index corresponding to the first signal.

A terminal receives a demodulation reference signal from a network. The terminal assumes the demodulation reference signal to be more aggregated in a frequency direction than in a case where a frequency band including one or a plurality of frequency ranges is used, when a different frequency band differing from the frequency band is used or when a wider subcarrier spacing is applied than the case where the frequency band is used.

Methods, systems, and devices for wireless communications are described. A network entity may map a demodulation reference signal (DMRS), a truncated sequence, and data in a delay-Doppler domain in accordance with a control signal. The network entity may apply a Fourier transform on the mapped DMRS, the truncated sequence, and the data to generate a signal in the time domain. The network entity may output, and a user equipment (UE) may receive, the signal in the time domain, including the DMRS, the truncated sequence, and the data. The UE may apply a Fourier transform on the received signal in the time domain to generate a mapping of the DMRS and the data in the delay-Doppler domain. The UE may perform channel estimation based on applying the Fourier transform on the received signal.

A sequence allocating method and apparatus wherein in a system where a plurality of different Zadoff-Chu sequences or GCL sequences are allocated to a single cell, the arithmetic amount and circuit scale of a correlating circuit at a receiving end can be reduced. In ST201, a counter (a) and a number (p) of current sequence allocations are initialized, and in ST202, it is determined whether the number (p) of current sequence allocations is coincident with a number (K) of allocations to one cell. In ST203, it is determined whether the number (K) of allocations to the one cell is odd or even. If K is even, in ST204-ST206, sequence numbers (r=a and r=N−a), which are not currently allocated, are combined and then allocated. If K is odd, in ST207-ST212, for sequences that cannot be paired, one of sequence numbers (r=a and r=N−a), which are not currently allocated, is allocated.

The present invention relates to a wireless communication system, and specifically, to a method and a device for the method which comprises the steps of: receiving resource allocation information for transmitting uplink data; generating a data demodulation reference signal (DMRS) sequence; and transmitting the data and the DMRS sequence on a frequency band indicated by the resource allocation information, wherein the frequency band comprises frequency resource units, and the DMRS sequence is generated for each frequency resource unit.

Techniques are described for selecting root pairs for Zadoff-Chu sequences for random access preamble and for signaling one or more values associated with the root pair to a user equipment (UE) by a base station. The described root pair selection methods for two-root physical random access channel (PRACH) preamble can enable the peak differences received at the UE from different frequency offsets (FOs) to be disjointed even considering error in UE side. The selection techniques can improve the performance of PRACH FO and time offset (TO) estimation.

A wireless communication method for use in a wireless terminal is disclosed. The wireless communication method comprises transmitting, to a wireless network node, a random access preamble selected from a plurality of predetermined preambles for a random access.

According to certain embodiments, a method by a wireless device is provided for beam-based random access. The method includes receiving, from a network node, a handover command, the handover command comprising at least one suitability threshold. Measurements of each of a plurality of beams detected by the wireless device are performed. The measurements of the plurality of beams are compared to the at least one suitability threshold. A particular beam is selected based on the comparison, and a random access procedure is initiated.