بهبود تخمين زاويه ورود براي سيگنال پهن باند در سيستم هاي راداري به كمك روشهاي مبتني بر زيرفضا

Improving wideband Direction of Arrival (DOA) in Radar System Based on Subspace Method

يكي از مسائلي كه در زمينه پردازش آرايه¬اي از اهميت بالايي برخوردار است مبحث تخمين زاويه ورود براي سيگنال¬هاي پهن باند و به عبارتي جهت¬يابي پهن¬باند مي¬باشد؛ يكي از متداول ترين روش¬ها در جهت يابي سيگنال¬هاي پهن باند اين است كه سيگنال پهن باند را به بين¬هاي مختلف فركانسي تفكيك نموده و سپس پردازش¬هاي لازم را در حوزة فركانس انجام دهيم. بر اين اساس روش¬هاي مختلفي براي جهت يابي سيگنال¬هاي پهن باند بيان شده است.در برخي از روش¬ها جهت يابي هر بين فركانسي به صورت مستقل از ساير بين¬ها پردازش مي گردد، كه به روش¬هاي ناهمبسته مشهور هستند.هدف از اين مقاله بررسي روشهاي مختلف جهت يابي سيگنالهاي پهن باند و مقايسه نحوه عملكرد هر يك و در نهايت استفاده از مفاهيم زيرفضا و تست تعامد در حوزه زيرفضا به منظور افزايش دقت تخمين زاويه ورود سيگنال در حالت پهن باند و مقايسه آن با روش¬هاي پيشين مي¬باشد.

Array processing is one of the issues that has been increasingly respected by researchers in recent years, especially in the field of radar and telecommunication systems. One of the important issues in the field of array processing is the question of the estimation of the angle of entry, in other words, orientation; it is worth noting that most guidance methods for narrow band signals are designed Is In practice, signals that are present in the medium or broadband, or in different frequency bands. One of the most commonly used methods for orienting broadband signals is that the broadband signal to different frequency bands and then perform the necessary processing in the frequency domain. Accordingly, various methods for orienting broadband signals are expressed. In some methods, the orientation of each frequency is independently processed from other interleaves, which are known as unidirectional methods. The purpose of this dissertation is to investigate the various methods for orienting broadband signals and compare the operation of each one, and finally, the use of sub-concepts and interconnection testing in the sub-area in order to increase the accuracy of estimating the signal angle of the broadband mode and compare it with previous methods.