Method for realizing high precision modulating radar pulse signal based on automatic test system

Abstract

The invention discloses a high-precision amplitude modulating method to receive synthetic aperture radar signal based on automatic testing, which comprises the following steps: constructing automatic testing system with signal source, source scaler, programmable power meter and communication control device; obtaining the relationship curve of signal power output by voltage-controlled waveshape code and source scaler; obtaining the modulated waveshape code to compensate the error of the source scaler amplitude according to the curve and SAR system parameter. The invention satisfies the precision modulating need for synthetic aperture radar signal, which reduces the clutter side lobe through compensating non-linear property in the source scaler according to the fitted modulating waveshape code of SAR system parameter.

Description

technical field [0001] The invention belongs to the technical field of automatic measurement, and relates to a modulation method and system for synthetic aperture radar pulse signals. Background technique [0002] The active scaler based on amplitude modulation (AMT: Amplitude Modulation Transponder) is a simple and easy-to-implement broadband active external scaler, which performs amplitude modulation on the received synthetic aperture radar SAR pulse signal, and then forwards it to the synthetic aperture radar SAR, after azimuth processing, due to amplitude modulation, images are generated on the upper and lower sidebands of the original Doppler spectrum respectively. The images do not contain any scene clutter, so that the external calibration signal can be separated from the ground clutter. Accurately realize a radar transceiver system, antenna, transmission path and external scaler closed-loop test circuit that is not affected by ground clutter, greatly improving the ac...

AI Technical Summary

Problems solved by technology

[0003] However, it is difficult to achieve accurate amplitude modulation of broadband X-band pulse signals, due to the constraints of the current level of independent microwave device technology in my country, such as the nonlinear input and output power of the amplifier used in the active scaler, and the nonlinearity of the power control device. The amplitude modulation has a great influence, which will cause the distortion of the amplitude modulation signal. As shown in Figure 1, the nonlinearity of the power control device leads to the distortion of the sinusoidal response and produces harmonic effects

Images