Distributed Bragg reflection laser-based chirp microwave generating device

Abstract

The invention provides a distributed Bragg reflection laser-based chirp microwave generating device, which comprises an arbitrary waveform generator used for providing an electric signal which is changed along with the time; a distributed Bragg reflection laser electrically connected with the arbitrary waveform generator and used for generating a chirp laser according to the electric signal which is changed along with the time; a tunable single-mode laser used for generating a tunable single-mode laser; a coupler connected with the distributed Brag reflection laser and the tunable single-mode laser and used for coupling the chirp laser generated by the distributed Bragg reflection laser to the tunable single-mode laser generated by the tunable single-mode laser; and a photoelectric detector used for receiving the coupled laser and then generating a chirp microwave. The chirp microwave generating device can generate chirp microwaves adjustable in shape, period and bandwidth, and super-high in time-bandwidth product and compression ratio.

Description

technical field [0001] The invention belongs to the field of microwave technology, in particular to a chirped microwave generating device based on a distributed Bragg reflection laser. Background technique [0002] Compared with the traditional radar, the new pulse compression radar can greatly improve the distance resolution under the premise of ensuring the detection distance. Broadband chirped microwave signal source, as the core device for transmitting signals, has important research value. At present, chirped microwave signals are generally generated based on electronic methods. However, limited by electronic bottlenecks, it is difficult to obtain broadband chirped microwave signals with a bandwidth exceeding 10 GHz. The photonics-based method has more advantages in terms of bandwidth, tuning performance, and anti-electromagnetic interference. [0003] The methods based on photonics mainly include frequency-time mapping method, beat frequency method and method based o...

AI Technical Summary

Problems solved by technology

The University of Ottawa proposed a variety of chirped microwave generation methods based on frequency-time mapping (ChaoWang and Jianping Yao, IEEE transactions on Microwave Theory and Techniques, 2008, 56(2): 542-553; Chao Wang and Jianping Yao, IEEE Photonics Technology Letters ,2008,20(11):882-884), the common disadvantages of this kind of methods are narrow center frequency tuning range, low time-bandwidth product and compression ratio

Jin-Wei Shi et al. from Taiwan, China proposed a scheme to obtain chirped microwaves by using DC light and fast frequency-sweeping distributed feedback (DFB) laser beating frequency (J.-W.Shi, F.-M.Kuo, et al., IEEE Photonics Journal, 2012, 4(1): 215-223; Jhih-Min Wun, Chia-Chien Wei, et al., Optics Express, 2013, 21(9): 11475-11481), this scheme can be compared With high time-bandwidth product and compression ratio, the shape of chirped microwaves can also be adjusted well. However, the principle of fast frequency sweep is based on thermal effects, so the tuning speed is slow, and the frequency of chirped microwaves can only be adjusted to the order of 10kHz. High frequency will be at the cost of reduced bandwidth, and the obtained chirped microwave flatness is poor, which will directly deteriorate the performance of the radar

Images