In order to measure the range, angle, and Doppler frequency of the target without any synchronization in the bistatic radar, a novel complete parameter estimation method based on separability of a pair of Linear Frequ...In order to measure the range, angle, and Doppler frequency of the target without any synchronization in the bistatic radar, a novel complete parameter estimation method based on separability of a pair of Linear Frequency Modulation (LFM) signal is presented. The Doppler fre-quency is measured by the time difference between two peak positions corresponding to the positive and the negative LFM return signal respectively. Direction Of Departures (DODs) and Direction Of Arrivals (DOAs) of the target are estimated by constructing a special eigenmatrix in which the es-timated angles can be extracted from the eigenvalue or the eigenvector. The target position can be located in the presence of the estimated DODs, DOAs and the signal delay difference between the echo and the directive wave signal in Multiple Input Multiple Output (MIMO) bistatic radar without any synchronization. The correctness and effectiveness of the proposed method are verified by the computer simulation.展开更多
In this paper, a multi-static system working in an active way is made up of ionospheric oblique backscatter sounding system (IOBSS) and two separate receiving stations, which adopts discontinuous wave mechanism. We ha...In this paper, a multi-static system working in an active way is made up of ionospheric oblique backscatter sounding system (IOBSS) and two separate receiving stations, which adopts discontinuous wave mechanism. We have advanced a new model that contains skywave condition to locate over-the-horizon targets. We use a single quasi-parabolic (QP) ionosphere model and an analytic ray-tracing program to obtain the coordinate registration (CR) index, which changes skywave group range to ground range. Also, IOBSS and other two receiving stations use this distance information to locate the target which is far away from the system. The analytic expression for the geometric dilution of precision (GDOP) under different station deployments are obtained, which shows GDOP is influenced by the system measurement precision, the stations' coordinates, and CR index. By computer simulation, we find that GDOP of isosceles right triangle deployment is smaller than that of line deployment and location precision will be improved with increasing base line length. The results indicate that this model is practicable with an acceptable range of error (less than 500 m under certain conditions in this paper).展开更多
A principle for choosing the coherent integration number and an improved Doppler beam sharpening(DBS)imaging algorithm for mechanic scanning radar are pre-sented in this paper.By compensating the range migration in wi...A principle for choosing the coherent integration number and an improved Doppler beam sharpening(DBS)imaging algorithm for mechanic scanning radar are pre-sented in this paper.By compensating the range migration in wideband airborne mechanic scanning radar,the proposed DBS imaging algorithm can efficiently improve the resolu-tion of a DBS image.In addition,based on the characteristic that the echo from the moving target will be modulated by the antenna pattern,a novel method used to locate the mov-ing target is also presented,which begins with the sub-aperture moving target detection followed by the sliding window detection.Proper location can be achieved by using this method.Finally,the results on real radar data are pro-vided to demonstrate the effectiveness of these proposed methods.展开更多
基金Supported by National Natural Science Foundation of China (No. 60601016)
文摘In order to measure the range, angle, and Doppler frequency of the target without any synchronization in the bistatic radar, a novel complete parameter estimation method based on separability of a pair of Linear Frequency Modulation (LFM) signal is presented. The Doppler fre-quency is measured by the time difference between two peak positions corresponding to the positive and the negative LFM return signal respectively. Direction Of Departures (DODs) and Direction Of Arrivals (DOAs) of the target are estimated by constructing a special eigenmatrix in which the es-timated angles can be extracted from the eigenvalue or the eigenvector. The target position can be located in the presence of the estimated DODs, DOAs and the signal delay difference between the echo and the directive wave signal in Multiple Input Multiple Output (MIMO) bistatic radar without any synchronization. The correctness and effectiveness of the proposed method are verified by the computer simulation.
基金Supported by the National High Technology Research and Development Program of China (863 Program) (2009AAXXX1302)
文摘In this paper, a multi-static system working in an active way is made up of ionospheric oblique backscatter sounding system (IOBSS) and two separate receiving stations, which adopts discontinuous wave mechanism. We have advanced a new model that contains skywave condition to locate over-the-horizon targets. We use a single quasi-parabolic (QP) ionosphere model and an analytic ray-tracing program to obtain the coordinate registration (CR) index, which changes skywave group range to ground range. Also, IOBSS and other two receiving stations use this distance information to locate the target which is far away from the system. The analytic expression for the geometric dilution of precision (GDOP) under different station deployments are obtained, which shows GDOP is influenced by the system measurement precision, the stations' coordinates, and CR index. By computer simulation, we find that GDOP of isosceles right triangle deployment is smaller than that of line deployment and location precision will be improved with increasing base line length. The results indicate that this model is practicable with an acceptable range of error (less than 500 m under certain conditions in this paper).
文摘A principle for choosing the coherent integration number and an improved Doppler beam sharpening(DBS)imaging algorithm for mechanic scanning radar are pre-sented in this paper.By compensating the range migration in wideband airborne mechanic scanning radar,the proposed DBS imaging algorithm can efficiently improve the resolu-tion of a DBS image.In addition,based on the characteristic that the echo from the moving target will be modulated by the antenna pattern,a novel method used to locate the mov-ing target is also presented,which begins with the sub-aperture moving target detection followed by the sliding window detection.Proper location can be achieved by using this method.Finally,the results on real radar data are pro-vided to demonstrate the effectiveness of these proposed methods.
