Pseudo-random Code Is Implemented In High-density Electrical Method

Pseudo random coding is a kind of according to the set in advance good pseudo-randomfunction, according to the operation need to generate the corresponding pseudo random signalencoding, the pseudo random signal has many order frequency, a pseudo random signal powersupply, multistage frequency characteristic can help high density resistivity method to overcomethe effects of polarization effect, by these have order frequency of the signal can be calculatedmore relatively accurate apparent resistivity of the same frequency, percentage dispersion rate,phase difference and other parameters, the address according to structure and types anddistribution of ore bodies below the surface play a great role.Various types of high density resistivity method and equipment at home and abroad, but onthe whole transmission techniques are very similar, with the duty ratio of1:1square wave signal.Dc grounding electrode polarization insuperable produced by the effects of polarization effect,can’t get a relatively accurate polarization, the conventional dc high density electrical method inorder to get relatively accurate polarizability are usually equipped with two sets of electrodesystem, namely a set of emission electrode and a set of measuring electrode, high cost, complexoperation, instrument bulky, field experiment is not convenient, high failure rate, and so onshortcomings make dc high density resistivity method and instrument have many inconvenienceto use.In this paper, the pseudo random coding in the high density resistivity method to measure theimplementation of research is introduced detailed, mainly including the human-computerinteraction interface design part, pseudo random signal generating section, the data processingpart and calculate relevant parameters, resistance test and resistance capacity test analysis section,the results section. More than a few part is the main research contents in this paper.The human-computer interaction interface part. The interface is designed with c++programlanguage, make the operator by manipulating the microcomputers communicate with high density resistivity method and instrument of executable program, the program developed by MicrosoftVisual Studio2005design platform, can be compatible with Windows xp, vista, vin7runtimeenvironment, such as the program includes parameter Settings, oscilloscope display parts,instrument back information display section, and the operator operation part. Thehuman-computer interaction interface can implement numbering command instrument operation,different ways of running operation, adjustable oscilloscope display when the length of thehorizontal axis and vertical axis, are free to set the data storage directory, you can add a customrun extremely way and so on.Pseudo random signal generated. Pseudo random signal generated part introduces thecompilation rules and generating principle of pseudo-random code, the third order, five order,seven order to generate pseudo random signal and its frequency spectrum fu, calculate the launchof the pseudo random signal transmitter three parts, the compilation of the rules for pseudorandom code is taken from ji-shan-he academicians act mentioned in the pseudo-random functionin the book named wide-area electromagnetic method and pseudo random signal electricity, itsgenerating principle similar to a binary number some addition rule, using the pseudo randomsignal transmitter is composed of-1,0,1of three digital code signal.Data processing and calculate relevant parameters. This part is to save measurement datafrom the man-machine interface of binary files extracted, after a series of processing, unitconversion come true value, and then calculate the resistivity, according to the correspondingorder of frequency, calculate the percentage of the corresponding order dispersion rate, phasedifference and other parameters.Resistance test and resistance capacity test analysis section. After a series of theoreticalanalysis, according to the resistance string data from the experiment comparing the theoreticalvalue, draw the conclusion.