15 results about "Transmit diversity" patented technology

A communication device, method, and computer program product optimize cyclic delay diversity (CDD) or linear delay diversity (LDD) for effective transmit diversity that increases transmit power by first and second transmit chains of the communication device. A controller of the communication device sequentially configures the first transmit chain to transmit an uplink signal and the second transmit chain to transmit the uplink signal with a different phase shift or time delay value. While sequentially transmitting, the controller monitors a measure of uplink signal quality at a network node for each sequentially changed phase shift or time delay values. The controller determines and uses an optimum value for the phase shift or time delay value that results in an optimum uplink signal quality over the evaluated sequence of different phase shift or time delay values.

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.

First user equipment (UE) exchanges at least a portion of data to be transmitted to a communication network with a second UE on a side channel. The UEs then send the data to the network at increased transmission power by using transmit antennas of both the first and second UEs, instead of just those of the first UE. In some cases, the second UE may transmit a variation of 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 may mix signals (e.g., having a same symbol) received at the same time period but at different sub-carriers, or mix the signals received at different time periods but at the same sub-carrier. The network may notify the UEs of a phase correction value based on the signals, and the UEs may adjust using the phase correction value.

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.

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may identify a transmit diversity configuration for transmitting multiple sidelink messages. The UE may identify a transmit diversity configuration that indicates a set of component carriers (CCs) available for sidelink communication. The UE may transmit, based on the transmit diversity configuration, a first sidelink message having a first redundancy version (RV) of a transport block (TB), and a second sidelink message having a second RV of the TB, on multiple CCs. In a second case, the UE may identify a transmit diversity configuration indicating a set of precoding matrices. The UE may transmit the first sidelink message, including a TB or an RV of a TB, precoded using a first precoding matrix and a second sidelink message, including a TB or an RV of a TB, precoded using a second precoding matrix on multiple CCs.

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 modulation domain cyclic delay Doppler shift, which comprises the following steps: obtaining a to-be-sent signal vector of a transmitting-end antenna; performing modulation domain cyclic delay Doppler shift on the to-be-sent signal vector to obtain a modulation domain signal vector, wherein the modulation domain cyclic delay Doppler shift comprises cyclic delay shift and cyclic Doppler shift; performing time delay Doppler modulation on the modulation domain signal vector to obtain a first time domain signal vector; adding a cyclic prefix to the first time domain signal vector to obtain a second time domain signal vector; and sending the second time domain signal vector to a double-fading wireless channel. The application not only can obtain full transmit diversity gain, but also can be used in a communication system of all time delay Doppler waveforms, has strong robustness, extremely low calculation complexity and wide application scenarios.

This application relates to the field of communication technologies, and discloses a multi-antenna transmit diversity indication method, a terminal, and a network side device. The multi-antenna transmit diversity indication method in embodiments of this application includes: A terminal sends first information to a network side device, where the first information includes at least one of the following: transmit diversity capability information of the terminal and transmit diversity state information of the terminal. The transmit diversity capability information is used for indicating a maximum quantity of physical antennas supported by the terminal for transmit diversity. The transmit diversity state information is used for indicating an actual multi-antenna transmit diversity state of the terminal and / or an actual quantity of physical antennas for multi-antenna transmit diversity.

Methods and systems efficiently deploy transmit diversity in wireless communication devices by predicting an expected transmit power increase based on operating characteristics and network resource allocation and comparing this increase to a threshold. If the increase exceeds the threshold, the device operates in dual transmit mode, optimizing power consumption and device efficiency. Embodiments can include factors such as antenna imbalance and maximum power reduction, ensuring dual transmit mode is engaged only when beneficial. This approach conserves battery life and reduces heat generation, improving user experience.

A method for uplink layer selection includes determining a location of a multi-antenna wireless device and identifying a zone for the multi-antenna wireless device based on the location. The method further includes selecting an uplink transmission mode for each of the multiple antennas based on the identified zone. In a zone closest to a serving access node, the multiple antennas utilize carrier aggregation and in a zone furthest from the serving access node, the multiple antennas utilize transmit diversity.

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.