Low-complexity algorithm and circuit design of correlation for time delay estimation

Abstract

Time delay estimation (TDE) is of great importance in a TDOA based location finding system and cross correlation is a typical method of TDE. This paper presents a new index named Equivalent One-bit Adding Times (EOAT) to evaluate algorithm's computation on bit level, based on which a low-complexity method of correlation is presented, meanwhile, we deduce the sufficient condition under which new method could be used, where condition coefficient F is put forward whose value is decided by input signal's nature, sampling rate and ADC's bits. At last, circuits are designed and experimental results show that improved method cost less circuit resources than traditional method with different degree as F equals to different value. Experimental data shows that if F<1, improved method take advantage. While F<0.05, circuit resources improved method cost are 50% less than that cost by traditional algorithm.