Device and method for realizing instantaneous frequency measurement using phase modulator

Abstract

The invention discloses a device and a method for realizing instantaneous frequency measurement using a lithium niobate phase modulator. The device and the method relate to the technical field of microwave and the technical field of optical communication, and are mainly applied to the field of electronic reconnaissance. The device comprises a laser, a polarization controller, a phase modulator, a standard single-mode optical fiber, an optical divider, a polarizer and an optical receiver, as shown in the appended drawings. By using the polarization sensitive property of the lithium niobate phase modulator and reasonably adjusting the polarization controller, phase modulation and intensity modulation can be realized at the same time. Based on the dispersion characteristic of the optical fiber, two frequency response functions opposite in change trend can be constructed. Thus, an amplitude comparison function obtained changes more quickly in a large band. By calculating the power ratio of upper and lower branches, the frequency of a to-be-measured microwave signal can be estimated. The measurement error of the device within the range from 1.6GHz to 24.6GHz is less than + / -0.3GHz.

Description

technical field [0001] The invention relates to the technical fields of optical communication and microwave technology, in particular to a device for measuring instantaneous frequency of microwave signals based on a phase modulator. Background technique [0002] In the field of electronic warfare, in order to intercept and identify radiation information from the enemy's radar or communication system, it is first necessary to estimate the operating frequency of its electronic system. The frequency of the radiation source can be estimated quickly through the instantaneous frequency measurement technology, so as to facilitate the realization of electronic reconnaissance, attack and defense. [0003] The traditional instantaneous frequency measurement system in the electrical domain generally realizes frequency estimation through microwave interference. The instantaneous frequency measurement system using microwave interferometry requires the use of RF power dividers and RF tra...

AI Technical Summary

Problems solved by technology

The instantaneous frequency measurement system using microwave interferometry requires the use of RF power dividers and RF transmission lines, which limits the expansion of the system's operating frequency

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