Joint ESPIRIT for time delay estimation of chirp spread spectrum

In this paper we present a technique to estimate the time delay of IEEE 802.15.4a chirp spread spectrum (CSS). Conventionally, the time delay can be estimated by the phase estimation of the samples of a dechirped sinusoid. We estimate the phase differences not between samples in a sub-chirp but between samples of adjacent sub-chirps to magnify the phase differences making this technique more robust even in low SNR. We used joint ESPRIT technique in order to retain the phase information of each dechirped sinusoids in low and high bands. We have verified this technique through simulation and implementation.