RU1831698C - Method of geomagnetic field signal transduction - Google Patents

Abstract

Usage: in the field of geophysics in the search and exploration of minerals, Summary of the invention: convert the magnitude of the geomagnetic field into a precession signal; in the selected conversion interval, an integer m of periods T0 of the reference frequency f0 is calculated, from which the value of the geomagnetic field value is determined and recorded. In this case, a sequence of n time intervals m (... n) is formed in the selected conversion interval, an integer QI periods T of the signal is calculated in each 1st time interval by the precession, the number mi of periods T0 of the reference frequency f0, the value of the geomagnetic field Tm is determined the form is Ј (fo / XtfQi / mi) where the y-gyro magnetic ratio is, and the duration of the first interval TI is set based on the ratio g-T n g, QI, and the duration of the remaining intervals m is set based on the ratio (i-1 ) T, 3 ... n), 2 ill. / Yo

Description

The invention relates to the field of prospecting and exploration of minerals by geophysical methods, in particular, using measurements of geomagnetic field.

The purpose of the invention is to improve accuracy. In addition, the implementation of the invention improves the speed and noise immunity of the conversion.

In FIG. 1 is a functional diagram of a device that implements the proposed method.

In FIG. 2 is a timing diagram illustrating the operation of the device of FIG. 1.

The device contains a generator 1 of the reference frequency, a block of 2 teams and sequentially

connected primary transducer 3, block 4 shapers, block 5 counters, block 6 division, adder 7, block 8 multiplication, as well as register 9 and recorder 10, moreover, the output of the generator 1 of the reference frequency is connected to the input of block 2 teams and one of the inputs of the block 4 shapers. The outputs of unit 2 of the command are connected to the 3rd input of unit 4 of the formers, as well as to the second inputs of unit 6, the adder 7, unit 8, and the recorder: 10. The output of register 9 is connected to the 3rd input of the multiplication block 8.

The sequence of operations when implementing the proposed method is illustrated by an example of a consideration of the operation of the device shown in FIG. 1.

00

with

u with

00

The device operates as follows. A primary transducer 3 with a frequency output converts magnetic field B into a frequency f (Fig. 26), which is related to the magnitude of the acting field by a ratio B. As a primary transducer, a quantum or nuclear-precession transducer is used, the reference frequency generator 1 generates a stable frequency f0 {Fig. . 2a), which enters the command unit 2 and the shaper unit 4. Block 2 of the commands generates command pulses that synchronize the operation of the entire device (blocks 4-8 and 10) and ensure the sequence of execution by the blocks of their functions. From the frequency f from the primary converter 1 in the block 4 of the formers, by the command (Fig. 2c) from the block 2 of the commands, using the signals from the generator 1 of the reference frequency, a conversion interval m (Fig. 2d) and n time intervals m (Fig. 2e-i ) according to the relation (i-1) T. Each of the generated intervals is filled with a frequency f from the primary converter 3 and from the reference frequency generator 1. Thus, in block 4, n packets of pulses of frequency f from the primary transducer 3 Qi-Qn and n packets of pulses of the reference frequency fo from the generator 1 of the reference frequency mi-mn are formed. These bursts of pulses are sent to block 5 counters, the first group of which counts pulses, and the second, mi-mn. At the end of the last time interval Tp, the command unit 2 sends a command (Fig. 2k) to the division unit 6. The division block 6 starts to receive the numbers QI and mi from the counter block 5 and divides the QI by mi. The result of the Qi / mi operation from the division unit 6 is supplied to the adder 7, which, according to a command (Fig. 2l), is produced from the instruction unit 6. leads the addition of Qi / mi, fulfilling

P

determination of the quantity Z (Qi / rrtj). This vei - 1

The value from the adder 7 is fed to the multiplication unit 8, to the second input of which from the register 9 the code of the multiplier f0 / (yn) stored there is supplied. On command (Fig. 2m) from block 2 teams in block 8 multiplying subtract

The product of the sums 2 (Qi / ms) by

the factor f0 / (y n), i.e. the value of the magnitude of the geomagnetic field Tm is calculated by the formula

Ј

 , Have mi

The output code of the quantity Tm from the output of the multiplication unit 8 is fed to the input of the recorder 10, which, with the arrival of a command pulse (Fig. 2n) from the instruction unit 2, writes the number Tm to the medium.

Thus, when using the proposed method with a cesium quantum converter su 3.5 Hz / nT at, 143 s and MHz, the value of the reading error in the prototype method (5 nT) is 5 times higher than in the proposed method (, 1 nT). With the same reading error, 1 nT and MHz, the TEM value in the prototype method (, 715 s) is 5 times greater than that of the proposed method (, 143 s). In addition, in the prototype method, the sampling error varies over a range of 5 times more than in the proposed method.

The proposed method can significantly increase the noise immunity of measurements due to the use of multiple results,

The accuracy (sensitivity) and speed of the proposed method is significantly higher than that of the prototype method.

In some cases, it is more convenient to form the time interval p m instead of P m. In these cases, temporary

interval n is formed based on the conditions

Claims (1)

g gK g + T. Formula from found and A method for converting a geomagnetic field signal, in which the magnetic field is converted into a precession signal using a primary transducer, in the selected conversion interval r, an integer m of periods T0 of the reference frequency f0 is calculated, from which the value of the geomagnetic field is determined and recorded, moreover, and in order to increase the accuracy, a sequence of n time intervals tg (... n) is formed in the selected conversion interval. in each 1st time interval, the integer QI periods T of the precession signal and the number mi of periods T0 of the reference frequency fo are calculated, the value of the geomagnetic field Tm is determined by the formula t i Ј fo Q 1m -p. ±, T mV where is the gyromagnetic ratio, when a is the duration of the remaining intervals, why is the duration of the first interval based on the ratio n set on the basis of the ratio G-T t G,. G | r + (i-1) T. i-2,3, ... n. / III I I t fi A LH ft 4fe / w