Research On Distributed Localization System Based On Optical Fiber Network

Distributed radar is an important development direction of the future radar,since it has significant advantages in concealment,positioning accuracy and anti-stealth capabilities.Multiple transmitters and receivers of the distributed radar are placed in different locations,and the information is collected at the central station using the transmission link,then data fusion processing is carried out to obtain more detailed information of targets.Due to the large bandwidth,low loss and being free of electromagnetic interference,microwave photonics can generate wideband quadrature signals and realize broadband RF signal channelizer.The optical fiber network can break through the limit of microwave transmission link,to supply large-capacity transmission of raw data in long-distance,thus avoiding the clock synchronization problems required by signal pre-processing in transmitter and receiver.Microwave photonics provides a technical basis for distributed radar to break bottleneck of electronics.In this paper,research of distributed multi-target positioning system based on fiber network is conducted.A new scheme based on microwave photonics is proposed for signal generation.A new channelizer based on coherent OFCs and SBS is proposed too.The main research contents of this paper include the following three aspects:1.A multi-target localization system based on fiber network architecture is studied,and the demands of the multi-target localization and the receiving system are analyzed theoretically.The multi-target location based on microwave photonic technology is realized,two targets are localized in a plane and location accuracy of 7.09 cm was achieved,verifying the feasibility of the proposed distributed multi-target positioning system.2.The phase chaotic signal generation scheme based on the polarization modulation optoelectronic oscillator is proposed and studied.The characteristics of the phase chaotic signal such as autocorrelation,cross-correlation,power spectrum and ambiguity function are analyzed theoretically.The advantage of phase chaos signal in edge suppression and performance of the multi-target localization is studied with detail.The phase chaos signal generation based on polarization modulation is realized experimentally,and its characteristics are analyzed to validate the theoretical model.3.Aiming at the requirement of broadband chaotic signal reception and processing,a microwave photonic channelization scheme based on coherent optical comb and stimulated Brillouin scattering is proposed and studied.An experiment is carried out.Photonic RF channelization with 4 channels,channel spacing of 80 MHz and a crosstalk suppression of more than 19.52 dB is realized.