Multiple-input multiple-output signal transmission transmitter, receiver, and system

Abstract

This invention relates to a multiple-input multiple-output (MIMO) signal transmission transmitter, receiver, and system. The transmitter includes multiple millimeter-wave array transmitting units. Each transceiver unit controls the output phase of its antennas using multiple phase shifters to pre-suppress spatial interference with spatial beamforming weights and further eliminate residual interference signals. The receiver uses a Doppler compensation unit to correct Doppler offset, then uses a spatial interference estimation unit to estimate the angle of arrival and calculate the beamforming weights, feeding these weights back to the transmitter. It can also calculate preprocessing parameters and feed them back to the transmitter to improve the desired signal quality and suppress interference. Furthermore, the transmitter and receiver together form a multiple-input multiple-output signal transmission system.

Claims

1. A transmitter for multiple-input multiple-output (MIMO) signal transmission, comprising: A plurality of millimeter-wave array transmitting units, each receiving an original signal, each millimeter-wave array transmitting unit comprising: a plurality of millimeter-wave antennas arranged in an array; and a plurality of phase shifters, one of which is connected to one of the plurality of millimeter-wave antennas. Each of the plurality of phase shifters receives a spatial beamforming weight fed back from a receiver, each spatial beamforming weight being a phase control value for each millimeter-wave antenna, used to suppress spatial interference before reception at the receiver. Each phase shifter controls the output phase of the connected millimeter-wave antenna with the received spatial beamforming weight, such that each millimeter-wave antenna outputs its original signal with a millimeter-wave transmission signal of a different phase, and these signals converge in space to form a millimeter-wave beam pointing in a predetermined direction, and the spatial interference is suppressed before reception at the receiver.

2. A receiver for multiple-input multiple-output (MIMO) signal transmission, comprising: A plurality of receiving antennas, each receiving antenna simultaneously receiving a plurality of millimeter-wave beams and extracting a plurality of millimeter-wave received signals from the plurality of millimeter-wave beams respectively; a Doppler compensation unit, connected to the plurality of receiving antennas, receiving the plurality of millimeter-wave received signals, obtaining the Doppler offset of each of the plurality of millimeter-wave received signals, and performing Doppler compensation on the plurality of millimeter-wave received signals according to the respective Doppler offsets to generate a plurality of compensated signals; and a spatial interference estimation unit, connected to the Doppler compensation unit, receiving the plurality of compensated signals, estimating the angle of arrival of each receiving antenna according to the plurality of compensated signals, calculating a plurality of spatial beamforming weights for suppressing spatial interference according to each angle of arrival, and feeding back the plurality of spatial beamforming weights to the transmitting end.

3. A receiver for multiple-input multiple-output signal transmission as described in claim 2, wherein the Doppler compensation unit processes the millimeter-wave received signal using one of the following methods: differential sequence, periodogram analysis, autocorrelation method, maximum likelihood estimation, Kalman filtering, or delay product method, to obtain the Doppler shift.

4. The receiver for multiple-input multiple-output signal transmission as described in claim 2, wherein the Doppler compensation unit comprises: An offset estimation module is used to detect the peak values ​​of the plurality of millimeter-wave received signals in order to obtain the differential phase of the plurality of millimeter-wave received signals, and then to estimate the Doppler offset. And a compensation module, connected to the offset estimation module, receives the Doppler offset, and performs Doppler compensation on the plurality of millimeter-wave received signals based on the Doppler offset to generate the plurality of compensated signals.

5. A receiver for multiple-input multiple-output signal transmission as described in claim 2, wherein the spatial interference estimation unit comprises: An angle of arrival estimation module receives multiple scanning beams emitted by multiple millimeter-wave array transmitting units, and uses the angle of maximum received power measured in the multiple scanning beams as the angle of arrival for each compensation signal; and a space interference zeroing module is connected to the angle of arrival estimation module, receives each angle of arrival, and establishes the steering vector of the desired signal of the multiple compensation signals and the steering vector of the space interference signal based on each angle of arrival, thereby calculating the multiple space beamforming weights.

6. The receiving end for multiple-input multiple-output signal transmission as described in claim 2 further includes: A symbol detection module is connected to the spatial interference estimation unit to receive each compensation signal, perform symbol detection on the compensation signal, and analyze the modulation constellation point corresponding to the compensation signal to determine whether each received compensation signal is close to the corresponding original signal.

7. A multiple-input multiple-output (MIMO) signal transmission system, comprising: a transmitter for MIMO signal transmission as described in claim 1; and a receiver for MIMO signal transmission as described in any one of claims 2 to 6.

8. A transmitter for multiple-input multiple-output signal transmission, comprising: A plurality of millimeter-wave array transmitting units, each receiving an original signal, each millimeter-wave array transmitting unit comprising: a preprocessing unit receiving a plurality of preprocessing parameters fed back from a receiver, and processing the plurality of original signals according to the plurality of preprocessing parameters to form a preprocessed signal, each preprocessed signal being used to suppress residual interference signals between the plurality of millimeter-wave array transmitting units before reception at the receiver; a plurality of millimeter-wave antennas arranged in an array; and a plurality of phase shifters, one of which is connected to one of the plurality of millimeter-wave antennas, each of the plurality of phase shifters receiving a spatial beamforming weight fed back from the receiver, each spatial beamforming weight being a phase control value of the respective millimeter-wave antenna, and used to suppress spatial interference before reception at the receiver. Each phase shifter controls the output phase of the connected millimeter-wave antenna with the spatial beamforming weight it receives, so that each millimeter-wave antenna outputs a preprocessed signal with a millimeter-wave transmission signal of a different phase, and they are converged in space into a millimeter-wave beam pointing in a predetermined direction. The millimeter-wave beam suppresses spatial interference and residual interference signals before being received by the receiver.

9. A receiver for multiple-input multiple-output (MIMO) signal transmission, comprising: A plurality of receiving antennas, each of which simultaneously receives a plurality of millimeter-wave beams and respectively extracts a plurality of millimeter-wave received signals from the plurality of millimeter-wave beams; A Doppler compensation unit is connected to the plurality of receiving antennas and receives the plurality of millimeter-wave received signals. It obtains the Doppler offset of each of the plurality of millimeter-wave received signals and performs Doppler compensation on the plurality of millimeter-wave received signals according to the respective Doppler offsets to generate a plurality of compensation signals. A spatial interference estimation unit, connected to the Doppler compensation unit, is used to receive the plurality of compensation signals, estimate the angle of arrival of each receiving antenna based on the plurality of compensation signals, calculate the plurality of spatial beamforming weights for suppressing spatial interference based on the angle of arrival, and feed the plurality of spatial beamforming weights back to the transmitter. The plurality of compensation signals are also used to estimate a spatial interference zeroing signal for suppressing spatial interference based on the angle of arrival of each signal. A multiple-input multiple-output (MIMO) interference calculation unit, connected to the spatial interference estimation unit, receives the spatial interference zeroing signal and calculates the spatial interference zeroing signal based on a sampling matrix formed by the received sequences of the plurality of millimeter-wave received signals to generate a plurality of preprocessing parameters. These preprocessing parameters are then fed back to the transmitter to suppress residual interference signals between the plurality of millimeter-wave array transmitting units of the transmitter.

10. A receiver for multiple-input multiple-output signal transmission as described in claim 9, wherein the Doppler compensation unit processes the millimeter-wave received signal using one of differential sequence, periodogram analysis, autocorrelation method, maximum likelihood estimation, Kalman filtering, or delay product method to obtain the Doppler shift.

11. The receiver for multiple-input multiple-output signal transmission as described in claim 9, wherein the Doppler compensation unit comprises: An offset estimation module is used to detect the peak values ​​of the plurality of millimeter-wave received signals in order to obtain the differential phase of the plurality of millimeter-wave received signals, and then to estimate the Doppler offset. And a compensation module, connected to the offset estimation module, receives the Doppler offset, and performs Doppler compensation on the plurality of millimeter-wave received signals based on the Doppler offset to generate the plurality of compensated signals.

12. The receiver for multiple-input multiple-output signal transmission as described in claim 9, wherein the spatial interference estimation unit comprises: An angle-of-arrival (AOA) estimation module receives multiple scanning beams emitted by multiple millimeter-wave array transmitting units and uses the angle of maximum received power measured in the multiple scanning beams as the angle of arrival for each compensation signal; and a space interference nulling module is connected to the AOA estimation module, receives each angle of arrival, and establishes the steering vector of the desired signal of the multiple compensation signals and the steering vector of the space interference signal based on each angle of arrival, thereby calculating the multiple space beamforming weights, and processing the compensation signal according to the multiple space beamforming weights to generate the space interference nulling signal.

13. The receiver for multiple-input multiple-output (MIMO) signal transmission as described in claim 12, wherein the MIMO interference calculation unit comprises: A sampling matrix construction module, connected to the spatial interference return-to-zero module, receives the plurality of spatial interference return-to-zero signals, and forms a sampling vector matrix from the plurality of spatial interference return-to-zero signals according to the receiving sequence of the plurality of millimeter-wave received signals; a channel response estimation module, connected to the sampling matrix construction module, estimates the channel response of each receiving antenna based on the sampling vector matrix; a preprocessing condition establishment module, connected to the channel response estimation module, receives each channel response, and establishes a plurality of preprocessing conditions required to suppress residual interference signals based on the estimated channel responses; and a preprocessing parameter solving module, connected to the preprocessing condition establishment module, receives each preprocessing condition and converts it into a matrix equation, and calculates the preprocessing parameters through matrix operations.

14. The receiver for multiple-input multiple-output signal transmission as described in claim 13 further includes: A symbol detection module is connected to the spatial interference estimation unit to receive each compensation signal, perform symbol detection on the compensation signal, and analyze the modulation constellation point corresponding to the compensation signal to determine whether each received compensation signal is close to the corresponding original signal.

15. An interference suppression system for multiple-input multiple-output (MIMO) signal transmission, comprising: a transmitter for MIMO signal transmission as described in claim 8; and a receiver for MIMO signal transmission as described in any one of claims 9 to 14.

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