A method of channelized digital demodulation based on poly-phase filter;

In order to solve the problems of capacitance type sensor with amplitude modulation, bad stability and drift existing and big nolinearity direct digital synthesis technology was used to improve the amplitude and frequency stability of source waveform and digital demodulation technology was used to improve the characteristic of linearity .

This paper investigates a highly effective digital demodulation technique used in digital automatic gain control(AGC).

On the basis of this,we propose the design scheme of digital detector based on CORDIC algorithm.

Application and effect of digital geophone;

Seismic data character of single-point digital geophone and processing strategy.;

However, based on full-digital seismic exploration technology, the digital geophone system is employed, as well as digital signals exported from digital geophones are digitally transmitted into key stations for arrangemen.

The performance of the digital detector used in cable receive channel has been improved obviously.

Digital Phase-sensitive Detection Technology in Precision Inductance Sensor;

The weak signal acquisition under the strong noise interference was solved by the digital phase-sensitive detection technique,and an analysis model was built by means of the pr.

Through optimizing regulation circuits and applying modular function design based on multi-DSP,auto gain control,in-time calibration correction and digital phase-sensitive detection,the multi-channel and multi-frequency weak signals of MIT coils array may be acquir.