Radio frequency interference suppression method for frequency-hopping satellite-borne microwave radiometer

Abstract

The invention discloses a radio frequency interference suppression method for a frequency-hopping satellite-borne microwave radiometer. The radio frequency interference suppression method comprises the following steps that step 1, a radiometer receiver selects a frequency band for normal operation, and the initial local oscillation frequency is fL0; step 2, a switch is switched to a matching load,and the voltage variance output by the matching load and observed by the radiometer receiver for multiple times is obtained through calculation; step 3, the switch is switched to an antenna output port, and the output voltage value VA(m) when the radiometer receiver observes the antenna for the m time is obtained; step 4, RFI detection is carried out according to the antenna output voltage value VA(m) and the voltage variance output by the matching load and obtained through observation, and whether RFI exists or not is judged; and step 5, if RFI interference does not exist, a local oscillator does not perform frequency hopping, and the radiometer receiver keeps the working frequency band; and if RFI interference exists, frequency hopping is carried out on the local oscillator. According to the method, radio frequency interference suppression is effectively carried out, meanwhile, the method is simple, the processing complexity is low, and the requirement for the whole satellite resources is relatively low.

Description

technical field [0001] The invention relates to a radio frequency interference suppression method. Background technique [0002] Microwave Radiometer (Microwave Radiometer) is a passive remote sensing instrument used to measure the microwave radiation energy of the target itself. It obtains the characteristic information of the target by receiving the microwave noise radiation of the target itself, and inverts the output data to obtain specific target parameters ( Mainly the brightness temperature value), so as to understand the physical characteristics of the detection target. Essentially, a microwave radiometer is a highly sensitive noise receiver. The microwave radiometer receives the brightness temperature of the target, amplifies the output signal of the antenna to a certain power through the receiver, and then performs detection to obtain the voltage value output by the radiometer, which corresponds to the received power of the radiometer. Calibration can obtain the ...

AI Technical Summary

Problems solved by technology

[0003] Although space-borne microwave radiometers generally work within the protection frequency band of radio astronomy, with the enhancement of human communication activities and the increase of illegal emissions, space-borne microwave radiometers work in low frequency bands, especially L, C, X The band is susceptible to man-made radio frequency interference from the ground, which makes the radiometer observation data unavailable, and at the same time causes a large number of regional data gaps, resulting in a decline in the observation capability of the spaceborne microwave radiometer, which has a certain impact on numerical forecasting

Moreover, with the development of 5G communication, spaceborne passive radiation remote sensing in the K, Ka, and V bands is facing great challenges, and it is urgent to develop spaceborne RFI radio frequency interference suppression methods to solve this problem

[0004] The disadvantages of existing radio frequency suppression methods are: first, it can only satisfy the suppression of narrowband interference, but cannot suppress broadband interference; second, the processing is complicated and requires high digital signal processing resources; third, it increases the radiation system data rate, increasing the demand for full star resources

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