آشکارسازی همدوس اهداف راداری با تموج میانی در كلاتر گوسی
محورهای موضوعی : مهندسی برق و کامپیوتر
1 - دانشگاه يزد
کلید واژه: آزمون GLR آشكارسازي رادار هدف تموج میانی همدوس,
چکیده مقاله :
در اين مقاله به حل آزمون فرضيه مرکب برای آشکارسازی همدوس اهداف راداری با تموج میانی در کلاتر اقدام شده است. در معدود تحقیقات انجامشده قبلی، در شرایط مشابه، بردار هدف بهصورت یک بردار تصادفی گوسی و مستقل از بردار کلاتر مدل شده است. در این مقاله بر مبنای همدوسبودن آشکارسازی و تعمیم مدلهای سورلینگ به حالت بینابینی، به مدلي ميرسيم که نشان میدهد استفاده از فرض گوسیبودن بردار هدف در چنین حالتی صحیح نمیباشد. بر این مبنا، بر اساس روابط آشکارسازی بهینه، آزمون مهم GLR برای آشکارسازی اهداف با تموج میانی در کلاتر گوسي محقق و عملکرد آن با آشکارسازهای تخمینزن - همبستگییاب (ECD) و آشکارساز خطی بیشینهکننده سیگنال به کلاتر (OF) مقایسه شده است. ضمناً در آشکارسازی، شیفت داپلر معلوم فرض میشود.
In this paper, coherent radar detection of moderately fluctuating targets in Gaussian clutter is performed. In the previous works, the target vector has been modeled as a Gaussian random vector that is independent of clutter vector. In this paper, based on the coherence assumption, by extending the Swerling models for radar targets to the moderate fluctuating cases, we propose a more accurate model for every fluctuating target. The proposed model shows that the Gaussian assumption for moderately fluctuating targets is not correct. Then, based on the proposed model, the optimal detection of moderately fluctuating targets in Gaussian clutter is performed and the GLR (Generalized Likelihood Ratio) test is obtained. Also, the ECD (Estimator-Correlator Detector) and OF (Optimal Filter) (that have been proposed as the best detectors in the previous works) are derived based on the new model. Computer simulation results show that the ECD has a superior performance than the other detectors. Nevertheless, the OF can be considered as an admissible detector because of the simpler algorithm and the performance close to the ECD. Although, the GLR detector has a suitable performance, but its performance is often lower than that ECD and OF while its algorithm is more complicated. Therefore, the GLR detector cannot compete to the ECD and OLD. Computer simulation results also show that these detectors do not have a convenient constant false alarm rate.
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