Broadband high-sensitivity millimeter wave receiving system based on carrier suppression

Abstract

The invention discloses a broadband high-sensitivity millimeter wave receiving system based on carrier suppression, which is characterized in that a dual-wavelength generation structure based on carrier suppression comprises that a single-tone signal generated by a microwave source directly drives an intensity modulator, and the intensity modulator works at a carrier suppression point to generate two coherent wave beams; a microwave photon down-conversion structure based on the intensity modulator comprises the following steps: modulating a radio frequency carrier signal to a beam of light wave in a carrier suppression dual-wavelength generation structure by using the intensity modulator, and keeping a-1-order sideband by using fiber bragg grating filtering; and a homodyne coherent detection unit which is used for performing homodyne coherent detection by using the other light wave beam generated by the carrier suppression dual-wavelength generation structure and a-1-order sideband output by the microwave photon down-conversion, so as to realize photoelectric conversion and complete demodulation from the millimeter wave radio frequency signal to the baseband signal. According to the invention, down-conversion of any millimeter wave radio frequency signal is realized, large-capacity and long-distance transmission of millimeter wave wireless communication is supported, the principle is simple, and the application value is high.

Description

technical field [0001] The invention relates to the technical field of on-chip microwave photonics, in particular to a broadband high-sensitivity millimeter-wave receiving system based on carrier suppression. Background technique [0002] In order to achieve higher-speed and larger-bandwidth wireless communication, the communication frequency is evolving to a higher frequency band. The millimeter-wave band is the development direction of future wireless communication due to its available spectrum resources of several GHz. Restricted by the baseband signal processing rate and the bottleneck of analog-to-digital / digital-to-analog conversion devices, direct detection of millimeter-wave radio frequency signals with a bandwidth of several GHz involves electrical domain mixing and filtering, and the device cost is high and difficult. Based on the microwave photon down-conversion technology, the millimeter-wave radio frequency signal can be directly converted to the baseband, makin...

AI Technical Summary

Problems solved by technology

For mmWave signal down conversion, using two or more lasers will not only increase the system cost, but also the linewidth and coherence of different lasers will cause signal drift

In addition, the signal output by the usual microwave photon down-conversion method is usually an intermediate frequency signal, which cannot be combined with coherent detection technology, and cannot take advantage of the performance advantages of coherent detection for weak optical signal detection

[0003] The traditional microwave photon down-conversion method uses an optical filter to extract the first-order sideband wavelength of the signal, and then uses direct detection or coherent detection to realize photoelectric conversion. In this method, the central wavelength of the optical filter needs to be changed according to the first-order sideband light wavelength. Adjustment, if the carrier frequency range of the millimeter wave radio frequency is too large, causing the wavelength of the first-order sideband light to exceed the passband range of the optical filter, the signal power loss will increase until it cannot be demodulated correctly, that is, the receiver bandwidth is limited

In addition, the passband of ordinary optical filters is not flat, resulting in different losses after passing through different optical wavelengths, which also makes the demodulation performance of the receiver for millimeter-wave signals with different carrier frequencies different, which is not conducive to the realization of ultra-wideband frequency hopping for millimeter-wave transmission

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