Frequency synthesis system and active millimeter-wave imaging equipment

Abstract

The embodiment of the invention discloses a frequency synthesis system. The frequency synthesis system comprises a direct digital frequency synthesis module, a phase-locked frequency synthesis module, a frequency mixing module and an output terminal, wherein the direct digital frequency synthesis module comprises a first direct digital frequency synthesizer, a second direct digital frequency synthesizer and a two-way selective switch, and the first direct digital frequency synthesizer and the second direct digital frequency synthesizer are connected with each other in parallel; the phase-locked frequency synthesis module comprises a first phase-locked frequency synthesizer, a second phase-locked frequency synthesizer, a third phase-locked frequency synthesizer, a fourth phase-locked frequency synthesizer and a four-way selective switch, and the first phase-locked frequency synthesizer, the second phase-locked frequency synthesizer, the third phase-locked frequency synthesizer and the fourth phase-locked frequency synthesizer are connected with one another in parallel. The frequency synthesis system disclosed by the embodiment of the invention can achieve agility, wide bandwidth, low phase noise and low stray of signals, and then enable active millimeter-wave imaging equipment to meet the imaging requirements of high resolution and rapid scanning.

Description

technical field [0001] The embodiments of the present application relate to the technical field of frequency synthesis systems, and in particular to a frequency synthesis system installed in an active millimeter wave imaging device. Background technique [0002] Millimeter waves refer to electromagnetic waves with a working wavelength of 10mm to 1mm, which are widely used in radar, remote sensing, spectroscopy and other fields. Millimeter wave imaging refers to the technology of identifying targets by using the scattering characteristics of objects on millimeter waves, such as high-resolution range images, synthetic aperture radar, and inverse synthetic aperture radar. Compared with low-frequency microwave imaging, millimeter-wave has a shorter wavelength, so the imaging resolution is higher; compared with optical or infrared imaging, millimeter-wave can penetrate clothing shielding, so it is very suitable for the detection of hidden weapons and dangerous goods in the human ...

AI Technical Summary

Problems solved by technology

[0004] The traditional frequency synthesis system mainly uses the phase-locked loop technology, although it can solve the technical difficulties of phase noise and spurs, but its frequency hopping speed and bandwidth cannot meet the requirements

The ping-pong frequency synthesis system can solve the difficulty of frequency hopping speed, but its system is complex, it is difficult to realize broadband applications, and its cost is relatively high

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