Spatiotemporal Reconnaissance Processing Technology

The high-resolution spatio-temporal two-dimensional (2-D) spectra estimation of wide-band signal acts an important role in modern array signal processing. Though abundant results acquired in theory, there are a lot of difficulties in the real time application of wide-band system. The development of micro-electronic and high performance algorithms of spatio-temporal 2-D spectra estimation offered probability for us to apply it on a real time system now. In prototype system, a L-shaped non-uniform linear array with 5 elements is utilized to receive spatial signal with carrier frequency among 2-18GHz. The entire frequency band is decomposed into 1GHz sub-bands and then is mixed to 1GHz base band. The base band output of each antenna is sent through a synchronous 250MHz undersampling channels. One antenna has a delayed 0.5ns relative to the others (prior to sampling). FFT is applied to data and spectra peak search is done, then using the data near the spectra peaks to compute two 4th-order cumulants matrix to form rotational invariance matrix pencil which the ESPRIT algorithm can be applied to. The non-aliasing frequency and non-ambiguous 2-D angles is obtained by the phase characteristic of eignevalue and integral search methodIn this dissertation, an algorithm of spatio-temporal 2-Dspectra estimation based on 4th-order cumulants was introduced and used to realize a prototype scout, a calibration algorithm in the wide-band array system is proposed. It also presents the development of hardware driver and application software for the prototype system. The technique of DSP and PCI local bus were applied in the system. Three FFT boards (TMS320C31 DSP) and one main processing board(TMS320C67 DSP) contributed to the system. We used the special computer as the controlling platform and Windows as the OS. The development of VxD driver software is describe in detail which is used to realize data transferring between hardware and application software, also data transferring among all boards. In array signal processing, various kinds of errors can degrade the performance of signal processing algorithm, errors calibration algorithm is also studied in this dissertation.Now our prototype system is in experiment, but the simulation result show that it can do non-alias frequency and 2D-DOAs of spatio-temporal undersampling digital signal and obtain the aimed performance. Though out system is designed to process stable narrow-band signal, it also provide experience for study of unstable signal parameter estimation system in theory and engineering, and establish a basement for the application of high-resolution spato-temporat 2-D spectra setimation.