Weak Array Sensor Signal Detection Method And Its Implementation

With the guidance of low level signal detection theory, this subject has developed a low level signal detection platform based on high speed DSP processor, which can realize the reliable detection of the μ -volt level even lower level array induction signal.The subject introduce the basic function the platform should realize, analyzing the noise source that influences the signal detection precision, considering the characteristic of the signal to be detected, choosing the digital and average low level signal detection method utilizing the correlation of the induction signal and the non- correlation of the noise, and carrying on theory analysis to this detection method, and the theoretical foundation of the realizing method of premodulator and data-gathering circuit has presented in this paper. On this basis , the concrete realizing scheme and the hardware block diagram of this signal detection platform are propeseded, the emphases of description are put on the key techniques adopted to improve the performance of signal detection, including techniques of designing low noise common mode rejection measurement amplifier, anti-aliasing lowpass filters, difference communication technique, over sampling approach, electromagnetic compatable technique and so on. Making use of DSP programme to realize and process the sampling signal, digital and average algorithm is implemented. Finally, a brief introduction of the distributed serial communication protocols is describled in order to guarantee the reliable data transmission of the eight path data-gathering slave module is stated in the thesis, the effective data transmission between the data-gathering slave module and master module is finished.Main innovations of this thesis are succeed in adopting a suitable detection method detecting low level array induction signal in logging instruments.