Multi-parameter mimo aeroborne time-frequency electromagnetic detection system and method

A multi-parameter MIMO aeroborne time-frequency electromagnetic detection system, comprising a flight platform, a transmitting subsystem, a receiving subsystem, and a measurement and control subsystem, wherein the transmitting subsystem and the receiving subsystem are hoisted under the flight platform,

• the transmitting subsystem comprises a first current transmitter, a second current transmitter, a transmitting coil, and a bucking coil, the transmitting subsystem is configured to inject a first current pulse into the transmitting coil through the first current transmitter to realize an excitation of a primary electromagnetic field, and to inject a second current pulse into the bucking coil through the second current transmitter to realize an excitation of a bucking electromagnetic field, and the primary electromagnetic field acts on underground media at different depths of a target detection region to generate a secondary electromagnetic field response;
• the receiving subsystem is configured to sample the first current pulse and the second current pulse and acquire the secondary electromagnetic field response, so as to transmit the sampled and acquired data to the measurement and control subsystem for data processing to obtain electrical property information of the underground media in the target detection region;
• and
• the measurement and control subsystem is configured to send a control instruction to the transmitting subsystem and the receiving subsystem according to a sampling result and at least one set detection parameter, and monitor a working status of the detection system, such that during a detection process, the measurement and control subsystem, by adjusting the first current pulse and the second current pulse in real time, enable the bucking electromagnetic field to offset a primary electromagnetic field signal entrained in the secondary electromagnetic field response, realizing adaptive compensation,
• wherein by changing at least one set parameter of the first current pulse and the second current pulse, the transmitting coil excites the primary electromagnetic field suitable for deep detection and shallow detection according to a set timing sequence, and the bucking coil synchronously excites a bucking magnetic field to offset primary electromagnetic field interference acting on the receiving subsystem;
• and the at least one set parameter comprises a frequency, an amplitude, a width, a waveform, a flow direction, and a timing sequence of each current pulse,
• in a state S1, the first current transmitter generates a time-domain bipolar-square-wave first current pulse of 1.25 Hz to 25 Hz and inputs the time-domain bipolar-square-wave first current pulse into the transmitting coil, wherein an amplitude of the time-domain bipolar-square-wave first current pulse is in a range of 200 A to 300 A, and the receiving subsystem synchronously acquires multi-parameter and multi-channel three-component magnetic field signals and horizontal electric field signals for the deep detection;
• in a state S3, the first current transmitter generates a frequency-domain multi-frequency first current pulse of 1 Hz to 20 kHz and inputs the frequency-domain multi-frequency first current pulse into the transmitting coil, wherein an amplitude of the frequency-domain multi-frequency first current pulse is in a range of 10 A to 50 A, and the receiving subsystem synchronously acquires multi-parameter and multi-channel three-component magnetic field signals and horizontal electric field signals for the shallow detection;
• and in states S2 and S4, the transmitting coil does not work to wait for an end of excitation of the first current pulse and the second current pulse.