Global Positioning System (GPS) is used in various fields such as communications systems, transportation systems,  e-commerce, power plant systems, and up to various military weapons systems recently. However, GPS receiver is vulnerable to jamming signals as the GPS signals come from the satellites located at approximately 20,000km above the earth. For this reason, various anti-jamming techniques have been developed for military application systems especially and it is also required for commercial application systems nowadays. This paper designs a commercial narrowband interference suppressor that removes narrowband and partial-band interference based on adaptive filtering technique mainly used for military application systems. It is installed between the antenna and the receiver simply reinforcing the anti-jamming function of the existing GPS receiver. The RF ASIC containing high-resolution 14-bit analog-to-digital converter is developed to get SWaP(Size Weight and Power) and price for commercial market.  Interference signals are removed in frequency domain using OFFT(Overlapped Fast Fourier Transform) algorithm based on digital signal processing. The performance of this interference suppressor is confirmed by measuring the ISR of the interference signal. 


Keywords: GPS, commercial, narrowband, interference suppressor, OFFT