A Novel Chirp Demodulation Scheme Based on SAGC for Amateur Radio Data Transmission

Abstract

Based on the sinusoidal automatic gain control scheme (SAGC), an equalizer implementation and a chirp demodulator have been proposed. With the 1-unit constant of SAGe output amplitude, an application as an equalizer has been implemented in order to eradicate the unwanted cut- off frequency characteristic of an amateur radio. According to loss of radio reception caused by the multipath fading phenomenon, a chirp modulation has played an important role to attenuate strong interferences in wireless communication. Thus, chirp demodulation based on modified SAGC has also been proposed in this paper. The equalizer application's result shows that the chirp signal amplitude has been stabilized to 1 unit at any carrier frequencies. Furthermore, the sawtooth wave has been recovered by using SAGC chirp demodulation before comparator and sample & hold block generate the information data. By the SNR range from 1 dB to 10 dB, the BER of the proposed SAGC chirp demodulation scheme is lower than the conventional one.