Cooperative Sensing Method to Improve Energy Detection Performance on Cognitive Radio

Wireless communication systems are developing rapidly along with increasing communication needs and community activities. The system is required to maintain the quality of communication in the density and scarcity of spectrum problems. There are still many spectrum holes that are not used by licensed primary users (PUs), especially in areas with moderate and low usage density. One of the solutions to increase opportunistic spectrum access without disturbing the PU is cognitive radio (CR). The spectrum allocation decision is based on the detection probability parameter on the secondary user (SU), which responsively detects the presence of the PU signal. Cooperative sensing is used to increase the reliability of detection in real situations when there is the uncertainty of noise, fading, or shadowing. This paper observes the cooperative sensing method of PU signal on the CR based on energy detection. The improvement of sensing performance is presented based on the parameters of detection probability. The method was based on energy detection using single and cooperative sensing in hard fusion rule. The evaluation was carried out by analyzing the detection probability on the variance of the number of SUs involved and the signal-to-noise ratio (SNR) level. The results showed that the cognitive radio system cooperative sensing method was better than single sensing. Cooperative sensing appears to be faster in reaching maximum detection probability at a low SNR level. The increasing number of users involved in cooperative sensing improves the detection probability and sensing performance.