Multi-receiver system for improved signal reception in spectrum monitoring

In the communications field, many methods have been introduced in order to improve the quality of signal reception. This is because various parameters can limit the quality of signal reception such as multipath fading and interference that results the signal with low signal-to-noise ratio (SNR) or no signal reception. This paper presents a multi-receiver system to improve signal reception and classification accuracy in radio communication system. Three receivers were utilized and each consists of antenna system, radio frequency (RF) front-end and down-conversion, time-frequency analysis, parameter estimation and signal classification. Then, the signal classification results are combined to obtain the final decision which is implemented using triple modulo redundancy (TMR) majority voting algorithm. The system was tested using six modulation signals (ASK1, ASK2, ASK3, FSK1, FSK2 and FSK3) with 100 trials for SNR from 2dB to 20dB. The performance of single-receiver and multi-receiver system is compared in terms of classification accuracy. Results show that the multi-receiver system was able to achieve 80 percent accuracy at minimum SNR of 2dB and the accuracy increases as the SNR increased.