8 results about "Transmit diversity" patented technology

Methods, systems, and devices for determining a transmit diversity across orbital angular momentum (OAM) modes are described. In some examples, a first device may select a subset of OAM modes for a transmit diversity scheme associated with communications between the first device and a second device. The first device may transmit an indication of the transmit diversity scheme, where the transmit diversity scheme may indicate the subset of OAM modes to the second device. The first device may then transmit signaling (e.g., a data packet, one or more signals, a data stream) to the second device using a set of transmitter circles of the first device. In response, the second device may transmit a feedback message, indicating signal strength measurements associated with one or more OAM modes. The first device may determine a set of OAM modes to use for subsequent signaling based on the feedback message.

The invention relates to the technical field of mobile communication, and discloses a 4T4R railway 5G vehicle-mounted repeater system based on an MIMO technology and a control method thereof, and the system comprises a roof 4T4R donor array antenna, a distributed carriage coverage 4T4R antenna, a near-end host unit, a cascade expansion unit, a far-end slave unit and a Beidou and inertial navigation positioning module. The units form a digital transmission link through optical fibers; according to the control method, a line electronic map and a scene-mode mapping table are loaded, train position information and adjacent cell measurement parameters are obtained, switching among spatial multiplexing, transmit diversity and beam forming is carried out under the scenes of stability, high quality, shielding, multipath, deep fading, multi-bend hills and the like, 4T4R and 2T2R self-adaption is achieved under the transmit diversity, and the method has the advantages of being simple in structure, low in cost and high in reliability. And when entering a strong interference area, forming null suppression interference based on synchronous signal block decoding and spatial domain and frequency domain filtering, and triggering soft / hard switching according to a measurement condition to improve continuous coverage and stability.

The application provides a signal processing method, relates to the technical field of communication, and is applied to a terminal device. The method comprises the following steps: receiving a first probe signal from a network device; determining a receiving phase difference according to the first probe signal; acquiring a receiving internal phase difference and a transmitting internal phase difference; and determining a transmitting phase difference according to the receiving phase difference, the receiving internal phase difference and the transmitting internal phase difference. The method provided in the application embodiment can be applied to a terminal device with multiple sets of transceiving hardware. The method splits a transmitting path into two parts, i.e., a transmitting channel and a path from an antenna to the network device. By acquiring the phase difference of the receiving channel, the phase difference of the transmitting channel and the overall receiving phase difference, the transmitting phase difference between different transmitting paths can be accurately calculated. The transmitting phase difference is applied to the transmitting diversity technology, which helps to enhance the uplink performance of the terminal device.

Methods, systems, and devices for wireless communication are described. A device may transmit excitation signals to a backscatter device at different frequencies using multiple antenna ports. For example, the device may transmit an excitation signal to a backscatter device using a first antenna port and a second antenna port based on one or more parameters. The excitation signal may include a first frequency component at a first frequency and a second frequency component at a second frequency. The device may perform a frequency exchange or symbol hopping when sending an excitation signal to the backscatter device.

The application discloses a time synchronization method, device and equipment of a dual-antenna transmission diversity, and relates to the field of dual-antenna transmission diversity. The method comprises the following steps: at a sending end, performing frequency domain CDD processing on one of two space-time streams, and adding a synchronization header to the two space-time streams, wherein the synchronization header comprises a long preamble formed by a 512-point M sequence, and the number of delay samples of the long preamble CDD processing is 256; at a receiving end, using a sliding search window with a value of 768 to obtain the time of three correlation peaks generated by the long preamble as a time synchronization point for time synchronization. The application can ensure that the second expected correct peak value is the highest in any complex multipath scenario, thereby avoiding synchronization errors in the complex multipath scenario and avoiding demodulation failure.

Certain aspects of the present disclosure provide techniques and apparatus for power leakage mitigation in transmit diversity. A method of controlling transmit diversity includes detecting that a first compensator among a plurality of compensators is 2024 / 138489 in transmit mode; outputting a first control signal to the first compensator to enable the first compensator for transmit mode in response to detecting that the first compensator is in transmit mode; and outputting a second control signal to a second compensator among the plurality of compensators to disable the second compensator from operating in transmit mode in response to detecting that the first compensator is in transmit mode.

The application relates to the technical field of wireless communication, and discloses a signal processing method and system based on time domain cyclic time delay Doppler shift, which comprises the following steps: obtaining a to-be-sent signal vector of a transmitting end antenna; performing time delay Doppler modulation on the to-be-sent signal vector to obtain a first time domain signal vector; performing time domain cyclic time delay Doppler shift on the first time domain signal vector to obtain a second time domain signal vector; adding a cyclic prefix to the second time domain signal vector to obtain a third time domain signal vector; and sending the third time domain signal vector to a double-fading wireless channel. The application provides a complete and ultra-low complexity scheme for obtaining transmitting diversity gain based on a time delay Doppler waveform communication system, which can not only obtain full transmitting diversity gain, but also has lower calculation complexity, saves communication resources, has good robustness, and has a wide application scenario.

This disclosure relates to "Multi-Device Synchronization and Data Transmission." A first user equipment (UE) exchanges, over a side channel, at least a portion of data to be transmitted to a communication network with a second UE. The UEs then transmit the data to the network with increased transmit power by using transmit antennas of both the first UE and the second UE, rather than just those of the first UE. In some cases, the second UE can transmit a change to the data sent by the first UE to perform transmit diversity and improve signal-to-noise ratio. To avoid unintended beamforming of the transmissions, the network can mix signals received at the same time period but at different subcarriers (e.g., with the same symbol), or mix signals received at different time periods but at the same subcarrier. The network can inform the UEs of phase correction values based on the signals, and the UEs can use the phase correction values to adjust.