Method and system for improving dynamic range in RF system

Abstract

The invention discloses a method and a system for improving a dynamic range in an RF system. In the system, an emitter, a power distributor, an amplifier and antenna are connected in turn, the antenna, a coupler, a low noise amplifier and a receiver are connected in turn, and a delay line and a vector regulator are connected between the power distributor and the coupler; the output end or input end of the power amplifier is connected with the input end of the delay line through the power distributor, and the output ends of the delay line and the vector regulator are connected with the input end of the low noise amplifier through the coupler; the power distributor is used for coupling part of carrier signals f; and the vector regulator is used for regulating the amplitudes of coupled carrier signals f and inverting the coupled carrier signals to obtain signals f1. The method and the system have the advantages that: firstly, a pre-feeding back method is used to inhibit radio frequency interference to a maximum degree; secondly, the amplitude of interference signals is lowered, the signal-to-noise ratio is improved, the dynamic range and sensitivity of a receiving system are improved; and thirdly, the structure is simple and easy to realize.

Description

technical field [0001] The invention mainly relates to a continuous wave radar, RFID and other transceiver systems, and mainly relates to a method and a system for improving the dynamic range in the RF system. Background technique [0002] Continuous wave radar, RFID and other transceiver systems usually use circulators as transceiver isolation devices, but the isolation of circulators is limited, and it is easy to cause excessive leakage of transmitted signals into the receiving path. Therefore, dual antenna technology is usually used to reduce the leakage in the receiving path Signal. Even so, there is still a major technical problem in the transceiver system, which is the interference of short-distance obstacles, such as radome. [0003] Since both continuous wave radar and RFID system use continuous wave to transmit signals, the received signals not only include the interference f1 of short-distance strong reflection targets, but also include the reflection signals f2 a...

AI Technical Summary

Problems solved by technology

Due to the large signal amplitude of the signal f1, the reflected echo of the short-distance obstacle is about 30dB lower than the transmitted wave, usually more than 20dB higher than the signal f2, which will reduce the performance of the receiver. The specific performance is: 1. Reduce the received signal The signal-to-noise ratio also reduces the receiving sensitivity of the receiver and shortens the range of communication; 2. Increases the range of signal changes and reduces the dynamic range of useful signals

3. It is easy to cause the low noise amplifier in the receiver to be saturated and have no gain, reduce the reliability of the receiver or even burn the receiver

Reduced detection capability of small target signals

4. Intermodulation signals are generated, which increases interference and system power consumption

[0004] There are several defects in the previous processing method. 1. The echo signal has a large range of changes, and the system requires a large number of ADs, which increases the signal processing burden of the system and increases the system cost.

2. Using a low noise amplifier with a high 1dB compression point alleviates the saturation pressure of the pre-stage low noise amplifier to a certain extent, but does not solve the problem of signal dynamic range

3. Often only focus on the leakage of the transmitted signal, while ignoring the strong reflection signal of close-range obstacles

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