Research On The Detection Technology And Instrument Of Electromagnetic Radiation

Electromagnetic wave has been widely used as a convenient communication carrier, the increasing electromagnetic energy density of people’s living environment, leading to the electromagnetic environment worsening. It is of great significance to design portable electromagnetic radiation measuring instrument with the advantages of wide frequency bandwidth, high precision, easy to operate, to help people understand the real electromagnetic radiation intensity and take effective protective measures.The domestic and abroad radiation protection standards about radio frequency and power frequency were compared and analyzed, respectively. The insufficiencies of domestic electromagnetic radiation protection standards and the basis of foreign standards were pointed out. On the basis of investigation, the overall design scheme of electromagnetic radiation detector was outlined, the probe module, display module, alarm module were given the specific hardware design scheme and realization method, respectively. The measurement principle and detection techniques of high frequency electric field, low frequency magnetic field and low frequency electric field probes were described with some emphasis. The design and processing size of the host shell and probe shell were introduced in detail.Software section focused on the software overall planning of electromagnetic radiation detector and corresponding function of each button, signal processing and related algorithms were described according to the characteristics of the electromagnetic wave detection. The main program including AD conversion, data processing, displaying, sound and light alarm subroutines were designed and debugged, the key part of the program code was given. By testing the system, the instrument achieved the functions of electric field strength, magnetic field strength, magnetic flux density measurements, triaxial switching and detection mode switching under high frequency electric field, in addition, low frequency magnetic field measurement, low-frequency electric field measurement, time and date displaying, status value adjustment, data recording as well as sound and light alarm.Electromagnetic radiation detector had three kinds of measurement modes, for high frequency electric field, the scope of frequency response distributed from 100 MHz to 3 GHz, and the sensitivity reached 0.001μW/cm2, for low frequency magnetic field, the frequency response distributed in the range of 6 kHz-60 kHz, and the sensitivity achieved 0.01 μT, for low frequency electric field, the frequency response scattered from 1 kHz to 40 kHz, plus 50 Hz, and the sensitivity reached the value of 0.1 V/m.The high-frequency electric field probe, the low-frequency magnetic field probe and the low-frequency electric field probe were calibrated using the signal sources, respectively. The corrected detector was taken contract tests with PMM8053B, and the measurement results were analyzed. The detector was tested by China Institute of Metrology and research, finally. The experimental results showed that EP-15 had a high accuracy of measurement. Whereas electric field strength of power frequency produced by the high voltage line people concerned, selecting typical radiation source to measure, the measuring results were consistent with the theoretical analysis, the accuracy was similar with foreign product standards.