Design of the A/D Conversion Circuit Based on ARM for the Time-Difference Method Ultrasonic Flowmeter

2011 ◽  
Vol 383-390 ◽  
pp. 516-523
Author(s):  
Xing Hong Zhang ◽  
Hui Zhang ◽  
Xi Hou Chen ◽  
Xian Quan Wang ◽  
Ji Qin Feng
Keyword(s):  
High Resolution ◽  
Low Power ◽  
Data Acquisition ◽  
High Precision ◽  
Difference Method ◽  
Data Acquisition System ◽  
Time Difference ◽  
Ultrasonic Flowmeter ◽  
Advanced Technology ◽  
Acquisition System

Because the high precision ultrasonic flowmeter has shortcomings of expensive, the A/D conversion circuit based on ARM for the time-difference method ultrasonic flowmeter is designed. On the basis of time-difference method ultrasonic flowmeter theory and the domestic and overseas advanced technology, a cost-effective low-power 12-bit ADC12DL040 chip and ARM processor LPC2138 are chosen for the design. According to the data acquisition system issues of the time- difference method ultrasonic flowmeter, the two-channel 12-bit low-power monolithic CMOS analog-digital conversion chip is adopted to design the nanosecond-level high-resolution data acquisition system. In this paper, the A/D chip peripheral pin circuit design is given, hardware structure diagram and software flowchart are also given. The input frequency of ultrasonic signal is 400 kHz and the sampling frequency is 8MHz.The experimental results indicated that the designed A/D conversion circuit is able to accomplish the high-speed and high-resolution ultrasonic echo signal sampling; the minimum resolution time of A/D conversion circuit is 0.305ns. The physical map of A/D conversion circuit for the time-difference method ultrasonic flowmeter is presented. The design of A/D conversion circuit for time-difference method ultrasonic flowmeter not only lower the production cost, but also lays a solid foundation for the research of low-cost and high-precision time-difference method ultrasonic flowmeter.

scholarly journals Development of a distributed hybrid seismic–electrical data acquisition system based on the Narrowband Internet of Things (NB-IoT) technology

2019 ◽  
Vol 8 (2) ◽  
pp. 177-186 ◽  
Author(s):  
Wenhao Li ◽  
Qisheng Zhang ◽  
Qimao Zhang ◽  
Feng Guo ◽  
Shuaiqing Qiao ◽  
...  
Keyword(s):  
Internet Of Things ◽  
Data Acquisition ◽  
High Precision ◽  
Data Acquisition System ◽  
Acquisition System ◽  
Geophysical Prospecting ◽  
Long Distance ◽  
Data Acquisition Board ◽  
Acquisition Processes ◽  
Electrical Data

Abstract. The ambiguity of geophysical inversions, which is based on a single geophysical method, is a long-standing problem in geophysical exploration. Therefore, multi-method geophysical prospecting has become a popular topic. In multi-method geophysical prospecting, the joint inversion of seismic and electric data has been extensively researched for decades. However, the methods used for hybrid seismic–electric data acquisition that form the base for multi-method geophysical prospecting techniques have not yet been explored in detail. In this work, we developed a distributed, high-precision, hybrid seismic–electrical data acquisition system using advanced Narrowband Internet of Things (NB-IoT) technology. The system was equipped with a hybrid data acquisition board, a high-performance embedded motherboard based on field-programmable gate array, an advanced RISC machine, and host software. The data acquisition board used an ADS1278 24 bit analog-to-digital converter and FPGA-based digital filtering techniques to perform high-precision data acquisition. The equivalent input noise of the data acquisition board was only 0.5 µV with a sampling rate of 1000 samples per second and front-end gain of 40 dB. The multiple data acquisition stations of our system were synchronized using oven-controlled crystal oscillators and global positioning system technologies. Consequently, the clock frequency error of the system was less than 10−9 Hz at 1 Hz after calibration, and the synchronization accuracy of the data acquisition stations was ±200 ns. The use of sophisticated NB-IoT technologies allowed the long-distance wireless communication between the control center and the data acquisition stations. In validation experiments, it was found that our system was operationally stable and reliable, produced highly accurate data, and it was functionally flexible and convenient. Furthermore, using this system, it is also possible to monitor the real-time quality of data acquisition processes. We believe that the results obtained in this study will drive the advancement of prospective integrated seismic–electrical technologies and promote the use of IoT technologies in geophysical instrumentation.

Sign in / Sign up

Export Citation Format

Share Document