1、3000 英文单词， 1.6 万英文字符 ，中文 5050 字 文献出处： Zivkovic D S , Markovic B R , Rakic D , et al. Design considerations and performance of low-cost ultrasonic ranging systemC/ Positioning Navigation & Communication. IEEE, 2013. Design Considerations and Performance of Low-Cost Ultrasonic Ranging System Dragan S.
2、 Zivkovic, Bogdan R. Markovic, Dejan Rakic, Srdjan Tadic Abstract Numerous systems for reliable, low-cost, indoor, ultrasonic sensing have been demonstrated during the past few decades. Existing solutions span very low-cost transducers to high-grade equipment. This paper presents design details of a
3、 low-cost, single-tone, ranging system. A set of experimental results is included in order to evaluate consistency between ranging results obtained from receivers with various architectures. The effects of channel equalization and signal pre- coding evaluated show how these systems can deal with rea
4、listic reflectors. Index Terms ultrasonic transducers, Cramer-Rao bounds, time of arrival estimation, indoor environments, CFAR, Tomlinson-Harashima pre-coder I. INTRODUCTION RANGING is an essential element in many robotics, industrial, and ambient-intelligence applications. Ultrasonic sensing is a
5、potential solution for reliable and low- cost indoor localization and ranging. In the experiments described within this paper, ultrasonic transducers, acting as both emitters and receivers, were used to locate reflectors based on the Time-of-Flight (ToF) of sound waves. The performance of ultrasonic
6、 distance measurement depends on employed signal bandwidth, which directly limits the amount of available information. The presented system uses low-cost, narrow-band, piezoelectric transducers (PZT). A focus of the work was to consider ranging consistency and investigate the benefit of bandwidth extension by channel equalization and a constant-false alarm rate (CFAR) 1 based detection of quality of ranging measurements. The system suggested presents core technology for more complex, sens
