Phase detection based range estimation with a dual-band robust Chinese remainder theorem

Range estimation with multifrequency phases is a common practice in localization systems. The challenge of this method is the phase ambiguity. Some Chinese remainder theorem （CRT） based phase un- wrapping algorithms have been proposed to solve the problem, where the wavelengths of the multifrequency signals need to be pair-wisely co-prime after they are divided by their greatest common divisor （gcd）. This condition may limit the application in practice. In this paper, a novel way based on a dual-band robust CRT is presented to reconstruct the distance from dual-band wrapped phases, where the pair-wisely co-prime condition is not necessarily needed. As more wrapped phases are involved to reconstruct the distance, the method can significantly enlarge the reconstruction range compared to the single band solution.