Abstract:This paper proposes a rotational direction algorithm based on time of arrival (TOA) ranging with UWB transmission equipment. During rotating UWB receiver around the human body, the maximum and minimum ranging can confirm the relative direction of the transmitter and receiver. But in the indoor complex environment, multipath effect, human body will cause large TOA ranging errors and error distribution is non-Gaussian. So, the relative orientation is indeed a template matching problem. This paper implements the secondary matching scheme, and analyzes the key parameters in the secondary matching for optimal value analysis and realizes high-precision horizontal direction detection. 4 degrees deviation is achieved, and the accuracy is improved by 9% relative to the single match method.