The Study Of Probing Theory And Application Analysis Of Bistatic Doppler Weather Radar

A bistatic multiple-Doppler weather radar system consists of one conventional Doppler weather radar and one or more remote passive receiver(s) with low-gain antenna(s). It is one among the new techniques in the atmospheric wind field probing aspect. The first atmospheric observation by a bistatic multiple-Doppler radar in China was operated for National Research Project, 'Mechanism and Predict Theory of Disastrous Weather over China', which facility was provided by Japan. The other meteorological echo data were obtained by a bistatic Doppler radar made in China in Hefei region in 2004. It's necessary to study the relevant probing theory, observation method, detection coverage and accuracy, retrieval technique and the others for a bistatic Doppler radar. This study will provide necessary experiences and technical support for further development and resolve some key problems in its meteorological application.The bistatic Doppler radar may become an important supplementary facility for our operational Doppler weather radar network. This study has potential application in meteorology and important meaning in practice.Focused on the probing theory and based on field observation data, an intensive study of bistatic Doppler weather radar has been done. The main work and important results are as followings:1. Resolution volume was analyzed in the study firstly. Bistatic scattering function and radar equation were derived based on Rayleigh-scattering condition and the considerations of radar transmitting wave polarization directions and space location of scatter volume. A series of simulative calculation of meteorological target scattering ability in all-directions and the distributions in space of passive radar received power have been done. The radar equation was used in the analyzing probing capability and range as well as sidelobe contamination. The results show that transmitting with vertical polarization is better than with horizontal polarization in bistatic radar technique. An agile transmitting with vertical/horizontal polarizations is useful for exploiting information, because the received power level is higher at upper altitude than at lower altitude in horizontal polarization transmitting case and reversein vertical polarization transmitting case. The stronger echo zone is around the baseline and its extension in receiver side.2. Sidelobe contamination is an important problem in bistatic radar technique, as its receiver with wide-beamwidth antenna. The main contamination sources and a method of eliminating the sidelobe effect have presented here.3. For operational application of bistatic Doppler weather radar, a design for radar antenna installation with parameter of target probing height is described here, which is convenient in calculation and practicable in operation. For a specified detection height, the longer baseline requires the higher antenna installation of transmitter or receiver.4. Establishing and preliminary checking the velocity retrieval method for bistatic Doppler radar were carried out. The retrieval accuracy of velocity fields derived from bistatic Doppler radars (one transmitter-one bistatic receiver or one transmitter-two bistatic receivers) were investigated. Upon analyzing the retrieval accuracy distribution in space, a suitable/reliable area is proposed in this paper. Based on field observational data of China-made facility, the quality control, velocity retrieval and its evaluation have been done.5. It is necessary to further investigate the data quality control, including velocity dealiasing, sidelobe contamination eliminating etc, based on more and more bistatic Doppler radar observational data in the future.