Front-end signal processing by the in-amp circuit, the fourth-order Butterworth low-pass optical filter and other parts of the system by the United States ADI's integrated instrumentation amplifier AD623, AD623 has an excellent CMRR (it increases with the gain), so that the smallest error , Power line noise and harmonic have been contained, high-precision straight through an exchange of properties and external resistance to gain easy one to 1000 within the framework of the advantages of changes in the detection of weak signals in the system as extensive pre-amplifier. The system uses two zoom in, zoom 10 times the first-class, second class Larger 100 times, a total of 1,000 times to enlarge. In the sampling of signals to be anti-aliasing filtering treatment, while filtering out high-frequency noise. This system is mainly for magnetic signals, their frequency in less than 1 kHz, so the filter cut-off frequency of not more than 1 kHz. The optical filter increase the frequency of flat and a good attenuation characteristics, thus, in many filtering circuit design be applied, tested the filter achieved good results. Dengkou I VHF remote control Taiwan is the main A596 route with Taiwan, before the expansion of the remote control of Taiwan's high-altitude communications channel using the four German company's R & S EU230A and SU250A separation of radio transceivers and transceiver may be adopted by the main double-redundant I work in low-altitude control and communications channel of the three Italian OTE's GTR-100 transceiver-one machine, and as a standalone work. As radio models are not unified, to the day-to-day technical maintenance has brought inconvenience. At the same time the use of low-altitude radio as a standalone OTE, aging equipment, there is a potential safety problems. After the expansion of low-altitude, high-altitude control and communications using the same type of control of radio communications from the previous three channel expansion to four channels, each channel are prepared mainly for redundancy, and with cavity optical filter to enhance the anti-interference capability.
作者:S-Blog