The Development Of Full Wave Multi-channel Synchronous Acquisition Subsystem For Distributed MRS+TEM

In order to solve the water crisis in many arid areas,it is imperative to find a quick,accurate,efficient and economical method for detecting groundwater.MRS exploration technology and TEM exploration technology is the commonly used groundwater exploration technology,MRS exploration technology has the unique explanation,the quantified results,comprehensive hydrological information,but there are also some shortcomings,just like weak anti-interference ability,limited detection depth,low efficiency,etc;TEM exploration technology has advantages of strong anti-interference ability,wide detection depth and high efficiency,but there are also shortcomings of non-unique interpretation,non-quantified results and other.MRS + TEM combined with the advantages of MRS exploration technology and TEM exploration technology advantages,learn from each other to make up for each other's shortcomings,so MRS + TEM combined technology has been rapidly developed,and has been repeatedly used in the practical engineering project.With the advance of field engineering,MRS + TEM instrument also exposed some problems,mainly in:1)In 2D / 3D detection,the current instrument using "one by one" detection mode,it leads to low detection efficiency.2)Dynamic range of signal conditioning module is small,poor gain adjustable,poor ability to adapt to different intensity signals.3)Single-channel mode,low efficiency,weak anti-interference ability,disability of carrying out reference noise reduction.4)Envelope acquisition,less data,data processing and inversion interpretation difficulties.5)The existing instrument is concentrated in a box,it is too cumbersome for field engineering applications.In order to solve the above problems,this paper developed a Development of Full Wave Multi-channel Synchronous Acquisition Subsystem for Distributed MRS + TEM,the main contents of which are:1)The use of "a multi-admission" detection mode,which improves the 2D / 3D detection efficiency,saves manpower and material resources.2)Designed a wide dynamic range of MRS signal conditioning module,the gain of preamplifier circuit,two amplifier circuit and programmable amplifier circuit all can be adjusted,programmable narrowband filter circuit using direct frequency synthesis technology,Q value and the center frequency is adjustable,for different test environments and different groundwater content,which lead to signal strength differences,it has higher applicability and better result.The design of a portable,practical TEM signal conditioning module,contains adjustable gain and wide use;220V mains charging,leads to convenient field engineering applications;current signal output,easy to carry out for long-distance transmission.High-frequency coil,low-frequency coil detection mode is optional,the output current signal can be transmitted over long distances.Designed multi-mode TEM signal receiving coil,high frequency,low frequency,overlapping loop mode is optional,has stronger applicability of shallow,middle,deep groundwater detection.3)Multi-channel synchronous acquisition,detection efficiency is higher,can be used for noise detection,more suitable for strong magnetic field interference environment.4)The use of full-wave high-precision acquisition has more accurate data processing and inversion interpretation,to prevent the interpretation of inaccurate which causes misleading wells.5)Designed a portable receiving subsystem,the lighter control module,signal conditioning module and acquisition module focused on the JS-17 box,easy to field engineering applications,improve the efficiency of field detection.Through the study of the above,developed a distributed multi-channel,full-wave,synchronous acquisition of the receiver subsystem,just the Distributed Full Wave Multi-channel Synchronous Acquisition Subsystem for MRS + TEM Combined Instrument,which can achieve a " Multi-channel” synchronization acquisition to achieve reference noise reduction,adaptive noise reduction;support network full-wave acquisition,in order to lay the foundation for inversion interpretation accuracy.