Received signal strength indication link like other metrics such as travel time measurement (time of arrival). Received signal strength indication In telecommunications, received signal strength indicator (RSSI) is a measurement of the power present in a received radio signal. RSSI is usually invisible to a user of a receiving device. However, because signal strength can vary greatly and affect functionality in wireless networking, IEEE 802.11 devices often make the measurement available to users. RSSI is often derived in the intermediate frequency (IF) stage before the IF amplifier. In zero-IF systems, it is derived in the baseband signal chain, before the baseband amplifier. RSSI output
Sonar signal processing and efficiency in data analysis . Thus, it is necessary to convert an analog signal into a digital signal by sample the signal in time domain . The operation can be realized by three devices: a digital conversion device, a dynamic range controller and a digital conversion device. For simplicity, the sampling is done at equal time intervals. In order to prevent the distortion (that is aliasing in frequency domain)after reconstruct the signal from sampled signal, one must sample at a faster rate .The sampling rate, which can well preserves the information content of an analog signal formula_1, is submitted