Method for suppressing pulse modulation continuous wave interference of notch filter assisted by variable gain amplifier

Abstract

The invention provides a method for suppressing the pulse modulation continuous wave interference of a notch filter assisted by a variable gain amplifier. The method comprises the following steps of:filtering input mixed signals by the notch filter; performing carrier wave stripping on filtered mixed signals, and respectively mixing the mixed signals with sinusoidal carrier wave replica signals and cosine carrier wave replica signals to obtain mixing results I(t) and Q(t); performing amplitude detection on the filtered mixed signals, and outputting a corresponding compensation coefficient Gain by the variable gain amplifier according to an amplitude detection result; compensating the mixing result I(t) to obtain a compensated mixing result I<Pamp>(t); and evaluating and outputting the actual value A(t) of a filtered and compensated signal amplitude according to Q(t) and I<Pamp>(t). According to the method for suppressing the pulse modulation continuous wave interference ofthe notch filter assisted by the variable gain amplifier, a traditional notch filter is assisted by the variable gain amplifier to achieve effective suppression for pulse modulation continuous wave interference, and can compensate for lost useful signals, which provides a basis for subsequent high-precision tracking and positioning.

Description

technical field [0001] The invention belongs to the technical field of anti-jamming of GNSS receivers, and in particular relates to a notch filter pulse modulation continuous wave interference suppression method assisted by a variable gain amplifier. Background technique [0002] Satellite navigation technology is widely used in aviation, aerospace, navigation and many civil fields. It can be used in daily life. It can provide time and frequency for network systems such as electric power, post and telecommunications, and communications. It can be used in geodesy, crustal movement monitoring, and disaster relief. Among other important tasks, the most important thing is that it can be applied in the military field, such as improving the target hit rate of guided weapons and ensuring the precise launch and recovery of combatants. [0003] However, the satellite signal transmission power is low, and after a long-distance transmission of more than 20,000 kilometers in free space,...

AI Technical Summary

Problems solved by technology

Compared with continuous wave interference in time domain, pulse modulation continuous wave interference can not only suppress satellite signals, but also further cause the loss of useful signals

The most widely used notch filter (Notch Filter) is a frequency-domain filtering method, which can effectively suppress continuous wave interference, but cannot make up for the loss of useful signals, so it cannot improve the carrier-to-noise ratio of satellite signals and receiver correlators. Consequences such as output amplitude drop

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