Time base distance estimation model for localization in wireless sensor network

Distance estimation based on time delay is more accuracy than the estimation based on power attenuation method, but it is hard to handle and needs so complicated hardware. This proposed model based on time delay to estimate a distance uses basic hardware to send a signal from one device and then the other device send it back. So, the time delay can be determined by using phase difference between sending and receiving signals and number of sending signal cycle before receiving signal available at sending devices.