Several algorithms to the problem of maintaining constant false alarm rate (CFAR) in closely multiple target situations and clutter edge environment have been proposed, but rarely consider closely multiple target inside clutter cloud which represent the worst radar environment. They may yield good performance theoretically, but they are not successful in practical hardware implementation since they have complex hardware because and high computational requirements with high processing time, which make them unsuitable for real time radar application and in order to overcome this problem a new algorithm of modified greatest of -constant false alarm rate(modified GO-CFAR) constructed. The proposed method implemented using a field programmable gate array(FPGA) chip that can match without problems almost with any radar receiver system with flexibility, by taking the inputs needed from the system that represent the radar receiver parameters.