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Register a new userIncreasing the Effectiveness of Deleting the Negative Overlap in Radars That use Linear Frequency Modulation LFM
زيادة فعالية حذف التداخل السلبي في الرادارت التي تستخدم التعديل الترددي الخطي MLF
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Aِl-Baath University ورقة بحثية
Publication date
2017
fields
Communication Engineering
and research's language is
العربية
Authors
عبد الغني شحود( باحث )
Created by
Shamra Editor
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نعرض دراسة لإمكانية تحسين أداء محطات الرادار التي تستخدم التعديل الترددي الخطي Linear Frequency Modulation:LFM باستخدام أزواج إشارات (LFM) الصاعدة و الهابطة للتخلص من إشارات التداخل السلبي, مع استخدام حزمة المرشحات المتقابلة ضيقة المجال مخصصة لقياس مدى الهدف, إن خرج هذه المرشحات المتقابلة موصولة إلى دارة طارح, و هكذا فإن الإشارات المنعكسة عن أجسام ثابتة ( تداخل سلبي ) ستدخل مرشحات لها نفس الترتيب مما يؤدي إلى طرح هذه الإشارات, أما الإشارات المنعكسة عن هدف متحرك سيختلف ترددها بقيمة الإزاحة دوبلرية و بالتالي ستهيج مرشحات مختلفة الترتيب لتمر عبر دارة الطرح دون أن يتم حذفها.
This paper presents a study of the possibility of improving the performance of the radar stations that use Linear Frequency Modulation (LFM) using signals pairs, uplink and downlink, to get rid of the negative interference signals, with the use of packet filters opposite narrow area dedicated to measuring the goal. The output of these packet filters is connected to subtractor circuit, so the reflected signals from fixed objects (negative interference) excite filters have the same arrangement leading to subtracting it, and the reflected signals from a moving target will vary its frequency value of the offset Doppler "fd" and thus excite different filters arranged to pass through the subtraction circuit without being deleted.
References used
БУЛЫШЕВ. А. В., ДМИТРИЕВ. В. Г., УЛЬЯНОВ. А. В., Основы Радиолокации и Радиоэлектроонная Борьба, Москва, 1983
СОСУЛИН Ю. Г. Теория Обнаруении и Оцениван Стохастических Сигналов. М. Сов. Радио, 1978
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