Digital Radar Level Signal Processing Method And System Realization

In recent years, with the rapid development of the petroleum industry and petroleum chemistry industry, more and more attentions have been atracekd to the accurate measurement of the liquid level in tanks. Rader Level Gauge is a sort of uncontacting tank liquid level gauging system. However, the current gauging system is not so accurate to meet the demands the mornden system. Digital Rader Level Gauge as a new measuring equipment can deal with the current limitations by its advantages such as high precision, free arithmetic, reliability, extensive application and anti-jamming ability. The main task of this dissertation is to study algrithms of digital signal processing and design softwares and hardwares of the Radar Level Gauge System.The dissertation makes a general review on the development and the current status of level measurement and principle, characteristics and application of digital level measureing technique. The advantadges of discrete Fourier transform and AR— model spectrum estimation method are analyzed and the limitations are also discussed.Traditional method is defective in analysing the signal transmitted by Radar level Gauge, which are in short sections, with excursive frequency and disrelated phasic. Thus , the new method of Sequence Correlation Matching with high adaptability and the ameliorative signal processing method FFT—AR—SCM, based on real signal , are brought forward. The results of simulation based on these method show that the new methods are efficient to improve the measuring precision.The dissertation covers hardware and software design, installation and debug of the digital signal processor. MCU is the System-on-a-Chip C8051F020 made in America by Cygnal Company. TURBO C is used to compile programs such as the signal processing algrithms, communications, display, scouting the core of the level radar. It plays an important role in research of Rader Level Gauge. Disposed liquid level signal is sent to Control Center to regulate the equipment.The result of digital signal processing shows that the FFT—AR—SCM is an effective way of obtaining high frequency precision with poor signal .This method contributes to the development of radar level gauging technology. The Radar Level Gauge not only improves the performance of tank's level gauging and the level of auto-control, but also has considerable economic benefits.