Design of Transient Electromagnetic Signal Acquisition System Based on FPGA

An acquisition system applying in transient electromagnetic method (TEM) receiver has been designed in this paper. The accuracy of acquisition has been improved by using a floating-point A/D with high input dynamic range, which is composed of programmable gain amplifiers (PGA) and a dual-channel 16 bit resolution ADC. The real-time performance can be ensured by using a field-programmable gate arrays (FPGA) as the main control unit to control ADC, PGA, data storage and communication interface. By integrating a soft core CPU, Nios II, in FPGA, the complexity of circuit design was decreased, and the work efficiency of system was improved. This system, which has good performance of real-time and high integration level, can meet the needs of TEM signal acquisition.