An apparatus for interpolation of polar signals in RF transmitters is disclosed. The apparatus comprises an estimation circuit configured to receive an input in-phase (I) quadrature (Q) signal comprising a plurality of input IQ samples having a first sampling rate associated therewith, and determine a selection metric value indicative of a position of an IQ trajectory associated with one or more input IQ samples of the input IQ signal. The apparatus further comprises a selection circuit configured to receive the input IQ signal and the selection metric value; and adaptively provide the input IQ signal to a first interpolation circuit that implements a first interpolation method or to a second interpolation circuit that implements a second, different interpolation method, for generating interpolated polar samples at a second, different sampling rate, from the input IQ signal, based on the selection metric value.

Disclosed is an anti-eavesdropping method for the Internet of Vehicles (IoV) based on intermittent cooperative jamming. The method comprises: on the premise of effectively preventing an illegitimate user V.sub.e from information eavesdropping, first establishing optimization problems for the purpose of minimizing an energy consumption of a cooperative jamming user V.sub.j; analyzing unique communication characteristics of the IoV based on the Wireless Access in Vehicular Environments (WAVE) protocol, to obtain time structures of physical-layer data packets in the IoV and physical-layer data packet duration; and calculating the shortest physical-layer data packet duration in the IoV; then solving an optimal cooperative jamming scheme for any available power range for the cooperative jamming user V.sub.j; and finally, conducting, by the cooperative jamming user V.sub.j, periodic repetition according to the solved optimal cooperative jamming schemes in a period of data transmission between legitimate users, until transmission between the legitimate users ends.

This disclosure provides a method for reference signal generation and a communications device. The method includes: in a case that indication information is received from a second communications device, performing first modulation and then discrete Fourier transform modulation on at least one of target-reference-signal sequences to generate a target reference signal, where the first modulation includes any one of the following: π/2-BPSK modulation and 8-PSK modulation, and the indication information is used to indicate that a first communications device uses the target reference signal for transmission.

The present disclosure relates to control information sending methods in a wireless communications system. In one example waveform control information sending method, a network device obtains control information that includes uplink transmission waveform indication information, and sends the control information to a terminal. After receiving the control information, the terminal determines, based on the control information, a waveform used to send uplink data.

Embodiments of this application disclose a data transmission method, apparatus, and system in backscatter communication, to improve spectrum usage efficiency of data. An embodiment of this application provides a data transmission method in backscatter communication, including: generating a first frame, where the first frame carries first data and second data, the first data and the second data in the first frame use different modulation schemes, the first data is sent to a first tag, and the second data is sent to a second tag; and sending the first frame to the first tag and the second tag.

Systems and methods providing for dynamic switching between the various waveforms on the downlink are described. Embodiments of a dynamic downlink waveform switching implementation may, for example, support utilization of one or more multiple carrier (MC) waveform (e.g., OFDMA) or other high peak to average power ratio (PAPR) waveform and one or more SC (SC) waveform (e.g., discrete Fourier transform-spread-orthogonal frequency division multiplexing (DFT-S-OFDM)) or other low PAPR waveform. Dynamic selection of a downlink waveform may be made by an access point based upon various metrics, including relative distance to a served an access terminal and the preference of downlink waveform indicated by a served an access terminal. A downlink waveform selection indication may be signaled from the access point to the served an access terminal using downlink control information (DCI).

Methods, systems, and devices for wireless communications are described. More specifically, the methods, systems, and devices support extending capability signaling to support higher modulation order baseband capability, such as higher order quadrature amplitude modulation (QAM), for example, 1024QAM. By way of example, a user equipment (UE) may transmit UE capability information to a base station (e.g., eNodeB (eNB), next-generation NodeB ((gNB)) in a connection establishment procedure. The UE capability information may include a UE category identifier and a baseband capability parameter. The baseband capability parameter may indicate a scaling factor for a first modulation order of a plurality of available modulation orders. The UE may communicate with the base station over multiple layers using corresponding modulation orders for the multiple layers.

A communication device including one or more processors configured to determine a first signal component of a received modulated signal; determine a second signal component of the received modulated signal; generate a phase shift of the first signal component; generate a phase shift of the second signal component; compare the phase shift of the first signal component and the phase shift of the second signal component with each other; and generate a plurality of constellation points, wherein each of the plurality of constellation point is based on the determination of the first signal component, the determination of the second signal component, and the comparison.

In a broadband wireless communication system, a spread spectrum signal is intentionally overlapped with an OFDM signal, in a time domain, a frequency domain, or both. The OFDM signal, which inherently has a high spectral efficiency, is used for carrying broadband data or control information. The spread spectrum signal, which is designed to have a high spread gain for overcoming severe interference, is used for facilitating system functions such as initial random access, channel probing, or short messaging. Methods and techniques are devised to ensure that the mutual interference between the overlapped signals is minimized to have insignificant impact on either signal and that both signals are detectable with expected performance by a receiver.

Transmitting a first data stream to a first station and simultaneously transmitting a second data stream to a second station. A method includes modulating a first signal by the first data stream to form a second signal, modulating the second signal by the second data stream to form a third signal, and transmitting the third signal by conversion to a transmission frequency to form a radio frequency signal, amplifying the radio frequency signal and providing the amplified radio frequency signal to an antenna. The modulation of the first signal is performed by scrambling of the first signal and the modulation of the second signal is performed by binary amplitude shift keying of the second signal, or the modulation of the first signal is performed by binary amplitude shift keying of the first signal and the modulation of the second signal is performed by scrambling of the second signal.