The Qcm Design For Lung Cancer Detection In The Design And Implementation Of Digital Frequency Meter

With the development of measurement techniques, Increasingly highmeasurement accuracy is required, and Involves a slight quantity of measurement inmany areas. Since discovered the piezoelectric effect of quartz crystals, quartz crystalmicrobalance (QCM) has been a lot of attention and research, because it has themeasurement accuracy of the ng level, has a very extensive and important study of theprospects for, while measuring the output frequency of QCM has very importantsignificance in the field of modern electronic measurement，because frequencymeasurement in the field of modern electronic measurement is one of the importantdirections. Because of the measurement for many parameters involves themeasurement of frequency or can be converted into a frequency measurement, andfrequency measurement has many points such as high accuracy, easy analysis etc, sothe measurement of frequency importance obviously.As a result of a quartz crystal microbalance with high precision, and small volume,and has the advantages of low cost, in recent years the development speed is very fast,Although because of its many industry direction specificity and application of differentno industry, but it has a broad application prospect, along with the electronicinformation industry in the direction of rapid development and measurementtechnology has enabled the development of quartz crystal microbalance towardsdigitalization, miniaturization, high frequency stability of the direction of development,these requirements for the QCM digital frequency meter accuracy, stability and putforward higher requirements.This paper first introduces the current cancer measurements of the variousmethods and their advantages and disadvantages, and then introduced the quartz crystalmicrobalance measurement principle, discussed the AT cut quartz crystal qualitysensitivity characteristic and temperature frequency and amplitude phase frequencycharacteristic, and the oscillating circuit principle and the choice of. Last focuses onintroduced for QCM-digital frequency of the hardware and software design.The issue of the design of high precision digital frequency meter includes mixing module, signal processing module, control module, and a display module. This paperuses QCM AT cut quartz crystal, using the quartz crystal resonator generated threeovertone, the quartz crystal electrode adsorption of rigid material quality differencesLead to the resonance frequency shift is measured. Because of the relatively largefrequency, inconvenient direct to measurement, thus can put the frequency and the10MHZ standard frequency mixing, resulting in a lower frequency. This frequency canbe directly into the MCU AT89S51count, the mathematical model of the count valueN is isolated, and error correction for digital tube display.The experimental results show that, the subject designed for QCM digitalfrequency meter at the common frequency range accuracy can be achieved in the QCM20ppm, so it can be used in measurement, because has the advantages of small volume,low cost convenient use in medicine and chemistry laboratory high pollution hasimportant significance.