The Performance Improvement of BASK System for Giga-Bit MODEM Using the Fuzzy System

In this paper we propose an automatic bandwidth control method for the performance improvement of Binary Amplitude Shift Keying (BASK) system for Giga-bit Modem in millimeter band. To improve the performance of the BASK system with a fixed bandwidth, the proposed method is to adjust a bandwidth of low pass filter in receiver using the fuzzy system. The BASK system consists of a high speed shutter of the transmitter and a counter and a repeater of receiver. The repeater consists of four stage converters, and a converter is constructed with a low pass filter and a limiter. The inputs to the fuzzy system are the reminder and integral of remainder of counter, and output is a bandwidth. We used a Viterbi algorithm to find the optimum detection from output of the counter. Simulation results show that the proposed system improves the performance compared to the fixed bandwidth.