Mostafa Taheri

Due to the limited energy of sensor nodes in wireless sensor networks. It providesa very short time for exchange on information between nodes. In order to prevent the frequency spectrum from being wasted, and taking into account that the small time of a sensor network is active. the use of radio-congnitive techniques for wireless sensor networks is recommende,. A sepctrum-based radio-frequency system is a wireless system that intelligently adapts its parameters to the environment as well as the needs of its users and thus enables high-reliability communications. the use of a radio cognitive network that leads to high transmission rates and energy efficiency is of interest. Because energy consumption is very important for wireless sensor networks, this article discusses how to reduce energy consumption in sensor radios. the four proposed algorithms for channel detection and decision-maiking by sensor nodes reduced energy consumption.