Microwave photon composite modulation synthesis ultra-narrow pulse generation system based on electro-optical modulation

Abstract

The invention discloses a broadband microwave frequency and phase composite modulation signal generation system based on electro-optical modulation, and the system carries out the frequency selectionof an oscillation starting signal through a frequency electrically-adjustable micro-disc optical filter in a photoelectric oscillation module, and achieves the frequency modulation. An electro-optic phase modulator in a phase modulation module is used for carrying out any phase encoding; the phase-locked loop module is used for carrying out phase locking on the generated signal, so that the coherence of the radar working waveform is ensured; the signal generator can generate a linear frequency modulation signal, a frequency coding signal and a frequency phase composite coding signal, and the flexible waveform can meet the target detection requirements in various complex scenes. Compared with the traditional electronic technical means, the microwave broadband signal generated by using the optical technology has the remarkable advantages of high frequency, large bandwidth, easy waveform reconstruction and the like.

Description

technical field [0001] The invention relates to the technical field of microwave signal generating devices, in particular to a broadband microwave frequency-phase composite modulation signal generation system based on electro-optical modulation. Background technique [0002] Modern radars need to have the characteristics of low interception and anti-jamming. Radars with low probability of interception often use signal forms such as frequency encoding, phase encoding, and noise modulation. Several signals have their own advantages and disadvantages. Phase-encoded signals have waveform agility, anti-interference and low interception capabilities, but are sensitive to Doppler frequency shift. The frequency coded signal can achieve larger bandwidth and higher peak side lobe ratio, but the general modulation law is relatively simple. Under the current technical conditions, it is difficult to achieve a large time-width-bandwidth product with a single phase or frequency encoding, ...

AI Technical Summary

Problems solved by technology

However, due to the nonlinearity of digital circuits, the output signal has many spurs, and it is usually difficult to achieve high-purity signal generation. In addition, the memory required to store large-bandwidth waveform data has exceeded the storage capacity of current mainstream FPGA chips.

Therefore, it is difficult to generate large-bandwidth arbitrary modulation signals in a digital way at this stage

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