Systems and methods for a non-data-aided (NDA) approach to advanced OFDM timing are provided. This approach allows for accurate OFDM symbol timing and synchronization by avoiding inter-symbol interference (ISI) in multipath environments where an earliest arriving signal may not be the strongest signal. The NDA approach may rely on generating and applying a bias correction to a combined correlation result of the multi-path signals.

Aspects of the present disclosure may involve use of a radio frequency receiver and in such a receiver, tracking multipath gains and delays of multipath reflections corresponding to an OFDM multipath transmission channel. The gains and delays are based on time-domain evolution of the channel impulse response. Multipath reflections are searched for and then used to calculate channel correlation information to provide channel estimations to aid in mitigating or cancelling distortion of the received signal.

Systems and methods for mitigating an effect interference. The methods comprise: receiving, by a device, a signal comprising a plurality of signal components; determining whether each signal component has a sufficient reconstructability; reconstructing each said signal component that was determined to have sufficient reconstructability using the received signal or an at least partially clean signal with other signal component(s) removed from the received signal; and using the reconstructed signal components to generate a modified received comprising the received signal with the signal components removed therefrom that (i) are devoid of a signal of interest and (ii) have sufficient reconstructability.

Systems and methods for mitigating an effect interference. The methods comprise: receiving, by a device, a signal comprising a plurality of signal components; determining whether each signal component has a sufficient reconstructability; reconstructing each said signal component that was determined to have sufficient reconstructability using the received signal or an at least partially clean signal with other signal component(s) removed from the received signal; and using the reconstructed signal components to generate a modified received comprising the received signal with the signal components removed therefrom that (i) are devoid of a signal of interest and (ii) have sufficient reconstructability.

A wireless communication system according to an embodiment includes: a wireless base station device configured to perform wireless communication of an orthogonal frequency division multiplexing (OFDM) method; a plurality of dynamic control relay devices for which a reradiation direction of incoming waves is dynamically controllable by the wireless base station device; and a wireless terminal device configured to perform wireless communication with the wireless base station device using a plurality of propagation paths that go through or do not go through the dynamic control relay devices. When the wireless communication is performed between the wireless base station device and the wireless terminal device using the plurality of propagation paths that go through the dynamic control relay devices, second OFDM subcarrier spacing is used, the second OFDM subcarrier spacing being spacing that is narrower than first OFDM subcarrier spacing that is used when the wireless communication is performed using the plurality of propagation paths that do not go through the dynamic control relay devices.

Disclosed are techniques for wireless communication. In an aspect, a wireless device determines a symbol configuration for transmission of SC-FDE waveform with zero gaps arranged between a communication channel part, RS part, and CP part. The SC-FDE waveform is transmitted to another wireless device, which processes the SC-FDE waveform.

Provided are a method, a system and a positioning location calculation device for realizing wireless positioning. The method includes: a positioning measurement device updating locally and statically stored PSS information according to movement information of the positioning measurement device when network connection is performed (200); receiving a positioning signal transmitted by each PSS in a band of a communication network on a determined wireless resource to obtain time information of the positioning signals transmitted by one or more PSSs (201); and calculating location information based on the time information about the positioning signals transmitted by the one or more PSSs and the PSS information according to a preset positioning mode (202).

Apparatus and methods for disrupting or preventing periodicity in DTC circuits are provided. In an example, a communication circuit can include a digital-to-time converter (DTC) and a processing path coupled to the DTC. The DTC can be configured to receive reference information, modulation information and first dither information, and to provide a modulated signal using the reference information, the modulation information and the first dither information. The processing path can be configured to receive second dither information and to cancel the first dither information using the second dither information, wherein the DTC is configured to disrupt processing periodicity of the communication circuit using the first dither information.

A method of performing uplink channel estimation and a base station using the same are provided. The method is applicable to serve at least two UE equipments (UEs) in a communication system. The at least two UEs are located in at least two beam sectors respectively. The base station comprises a plurality of antennas. The method includes: determining whether multipath of the at least two UEs passing through a same beam sector; assigning a first and a second training sequence for a first UE and a second UE of the at least two UEs respectively; receiving a reference signal, wherein the reference signal is transmitted by the first UE and the second UE according to the first and the second training sequence; and performing channel estimation for the first UE and the second UE according to the reference signal, the first and the second training sequence.

A precoding method, a precoding apparatus, a Frequency Domain Equalization (FDE) method, and an FDE apparatus are provided in the embodiments of the present invention. The precoding method includes: performing offset modulation for a transmitting signal vector; calculating a precoding matrix according to the offset-modulated transmitting signal vector and a receiver decision signal vector, where the precoding matrix is used for performing precoding for the transmitting signal vector; and performing precoding for the transmitting signal vector according to the precoding matrix. Linear precoding is performed by using the offset-modulated signal on the transmitter, and therefore, the interference caused by multiple antennas and multipath propagation is reduced, the system BER is reduced, and the complexity of implementation is low.