Radio Frequency Cancellation Device and Method for Interference Reconstruction in Digital Domain

Abstract

The invention discloses a co-location radio frequency interference cancellation device and method for digital domain interference reconstruction. The device includes modules such as digital delay, interference reconstruction model, coefficient identification algorithm, digital-to-analog converter, cancellation link and combiner, among which the digital delay, interference reconstruction model and coefficient identification algorithm run on the digital signal processing device superior. The cancellation method includes the following steps: establishing an interference reconstruction model according to the characteristics of the transmission link, the wireless channel and the cancellation link; realizing digital delay according to the transmission and reception digital signals to align the transmission and reception digital signals; using the digital delay data and the reception data Implement static coefficient identification of model coefficients. By combining the advantages of digital domain interference reconstruction and radio frequency analog domain interference cancellation, the present invention solves the problem of insertion loss of high-power signals, reduces the influence of interference on the dynamic range of receiver analog-to-digital converters, and ensures broadband signal the counteracting effect.

Description

technical field [0001] The invention relates to an electromagnetic compatibility technology of a co-located wireless transceiver radio frequency system, in particular to a radio frequency cancellation device and method for digital domain interference reconstruction. Background technique [0002] In space-constrained systems such as warships, tanks, and aircraft, the dense deployment of a large number of high-power transceivers and high-sensitivity receivers makes electromagnetic interference between co-located RF systems increasingly serious. Interference cancellation technology is an important technical means to solve the problem of co-location radio frequency interference, which has the advantage of high spectrum efficiency. The principle is to extract part of the reference signal at the transmitting end, and obtain a signal with the same amplitude and opposite phase as the interference signal at the receiving end through the adjustment of delay, amplitude and phase, and t...

AI Technical Summary

Problems solved by technology

Limited to the characteristics of analog devices, there are several problems in the interference cancellation in the analog domain: (1) Difficulty in implementation: all taps of the analog interference cancellation unit need to be implemented by analog devices. In the high-frequency radio frequency domain, multi-channel Precise delay, amplitude and phase adjustments are difficult

(2) High insertion loss: In the analog domain, it is necessary to perform coupling sampling of the reference signal at the transmitting end, and sampling of the error signal at the receiving end, which will cause signal loss of the transmitter and receiver, reduce the range of the transmitter, and reduce the receiving end. Reduced machine sensitivity

(3) Weak adaptive adjustment ability: each tap delay is fixed and designed in advance according to the coupling characteristics between transceiver links

In the actual transceiver RF system, the interference link between the antennas generally changes with the surrounding environment. At this time, the tap of the cancellation unit cannot be adjusted adaptively according to the change of the interference coupling link, which will cause a significant drop in interference cancellation performance.

(4) Slow cancellation speed: Since the reconstruction and elimination of interference signals are all implemented in the analog domain, the cancellation speed depends on the response speed of analog devices, and there is limited room for improvement

However, digital cancellation technology also has two important shortcomings: (1) Analog-to-digital converter (ADC) dynamic problem: when the power of the interfering signal is large, the dynamic range of the useful signal is reduced, and the quantization error of the ADC limits the performance of the receiver

This problem is the bottleneck restricting the interference cancellation technology in the digital domain

(2) Nonlinear distortion problem: The interference coupling path in the analog domain is the spatial coupling between antennas, which is a linear model; while the interference coupling path in the digital domain includes the RF transmission link and the reception link with a large number of nonlinear devices, which brings Nonlinear distortion cannot be eliminated by traditional linear models

[0005] Chinese patent ultrashort wave electromagnetic interference cancellation device (application number 201010198092.0), a multi-channel interference cancellation device (application number 201518001239.6), co-site coupling interference cancellation device (application number 201518001240.9), adaptive broadband interference cancellation device (application number No. 201320001505.0), an adaptive interference cancellation device and its debugging method (Application No. 201110223502.7) are all interference cancellation schemes in the analog domain, which cannot overcome the complexity of implementation, insertion loss, adaptive adjustment, and cancellation speed. Problems with Domain Cancellation

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