Radio frequency amplitude limiting protection circuit

Abstract

The invention discloses a radio frequency amplitude limiting protection circuit. The radio frequency amplitude limiting protection circuit comprises a signal splitting and integrating module and an amplitude limiting module, wherein the signal splitting and integrating module splits an input signal into a plurality of signals to be processed and transmits the signal to be processed to the amplitude limiting module; the amplitude limiting module comprises corresponding branches in the number corresponding to the number of the signals to be processed to process the signals; the branches have the same topological structure; each branch basically causes no loss on input low-power signals, has the characteristic of weakening high-power signals and returns the signals to the signal splitting and integrating module; the signal splitting and integrating module integrates the returned signals and outputs the integrated signals. The characteristics of a 3dB 90-degree bridge and a mechanism of the radio-frequency conductive modulation effect of PIN diodes are utilized, the bridge and the PIN diodes form the radio frequency amplitude limiting protection circuit capable of improving mismatch under the amplitude limiting condition, and even under the amplitude limiting condition, signals at the input and output ports can be well matched, and the radio frequency amplitude limiting protection circuit has basic functions of an amplitude limiting protection circuit.

Description

Technical field [0001] The invention relates to a radio frequency circuit, in particular to a radio frequency limiting protection circuit. Background technique [0002] Radio frequency receivers are prone to saturation, jamming, signal distortion or even excessive power in the reception of high-power signals, which will burn circuit components. Therefore, it is necessary to connect a limiter protection circuit before the radio frequency receiver, and the limiter protection circuit needs It has the following characteristics: the protection circuit should have extremely low insertion loss when the input signal is lower than the threshold; the protection circuit should have extremely high isolation when the input signal is higher than the threshold; the protection circuit should have a short response time, At the same time, it can withstand higher power shocks. [0003] Traditionally, this type of limiter protection circuit is composed of Schottky diodes, using the characteristics of...

AI Technical Summary

Problems solved by technology

However, when the limiting circuit is used in the middle of the RF link of the system, especially in some sensitive circuits such as power amplifier circuits, this circuit mismatch may cause the performance of the power amplifier to deteriorate or even self-excited to burn out

Images