SU857895A1 - Method and device for controlling seismic oscillation source - Google Patents

Description

(54) METHOD OF MANAGING THE SOURCE OF SEISMIC OVERSHIPS AND THE DEVICE FOR HIS THE INVENTION The invention relates to radio control of a source of seismic vibrations during seismic prospecting. A device for controlling a seismic source by radio is known, the operation of which is based on transmitting a specific code to control a seismic source by changing the frequency subcarriers and transmitting from the source to the seismic station the marks of the start of the excitation and the vertical time, corresponding to the onset of excitation and vertical time fl. However, frequency filters are used to make the moment of frequency change, the main disadvantage of which is the complexity of their tuning. Devices using this frequency separation principle have imposed stability requirements on the IMPLEMENTATION of the frequencies of the signals transmitted over the communication line. The closest to the proposed technical entity is a seismic radio communication system, which uses a method for controlling the source of seismic vibrations, including the generation and transmission of a command signal by changing the subcarrier frequency and deciphering it by determining the points of frequency change 2J. A device for implementing a known method consists of a communication line, a command and control points, each of which contains a serially connected tweeter, a radio station shaper, a scheme for determining the moments of frequency change, including a coincidence circuit and a decoder. In this system, the command for source excitation is represented is a signal from a sequence of periods of the first frequency and a certain number of periods of the second frequency, twice the first one, which actually is a coma Ndu on excitement. At the point of the input source ;; is converted into a sequence of pulses of different durations, the first of which start the first of two series-connected single vibrators, and the duration of the second start pulse is chosen such that it covers the double frequency input pulses and does not cover single frequency pulses. The double frequency pulses arrive at the counter, when their number coincides with the given radio station and source code, it is switched on to transmit, and after a certain period of time, elastic oscillations are excited. When the radio station is turned on, it transmits the days to transmission to the seismo.

A station has a signal of a certain frequency, which is replaced by a double frequency signal at the moment of the start of the excitation and a signal of the first frequency, at the time of arrival of the vertical time signal.

The disadvantages of this system are the laboriousness and complexity of its setup in the manufacture and operation in field conditions and repair in the absence of the necessary set of measuring instruments,

The purpose of the invention is to simplify hardware synchronization.

The goal is achieved by the method of controlling a source of seiscic oscillations, which includes generating and transmitting a command signal by changing the subcarrier frequency and decoding it by determining the moments of frequency change, determining the reference frequency for the command signal frequency and determining the number of clock pulses for the half-cycle of the command signal, and the command signals are obtained by dividing the clock frequency.

In a device for the implementation of a method consisting of a communication line, a cocked and controlled points, each of which contains series-connected encoder, radio station, driver, circuit. Definition of the moments of frequency change, including

work.

The device consists of a command post containing a radio station

1, encoder 2, decoder 3, clock generator 4, frequency divider 5, driver 6, counter 7, coincidence circuits 8 and 9 and controllable item containing radio station 10, generator 11, decoder 12, clock generator 13, frequency divider 14, shaper 15, counter 16, circuits 17 and 18 coincidence, comparison circuit 19.

The device works in the following way.

When the device is turned on at the command point (seismic station), the clock generator 4 starts to work, from which the signal with frequency f (diagram 20 figure 2) through the frequency divider 5 goes to the encoder

2, Frequency of signal f2 output of frequency divider 5 (diagram 21 figure 2)

several times, for example, 8, less than the frequency generated by the clock generator 4. From the encoder's output, the signal is a frequency that is a command. Attention is sent to the transmitter of radio station 1. A command from a seismic station (not shown) encoder 2 outputs a certain number of frequency periods f2 , Being a Fire command chart 22 of figure 2), and switches the radio station to receive mode.

Claims (2)

When receiving the Attention command, the device is turned on at the source. At the same time, the clock generator 13 starts working, from the output of which the signal with frequency f4 (diagram 25 of Fig. 2) coincides, and the decoder, serially connected clock generator and frequency divider, the output of which is connected to the encoder, are entered into the command and control points for determining the moments of frequency change, a clock counter has been entered, the 1st input of which is connected to the clock pulse output, the setup input is connected to the output of the driver, and the output connected to the circuit inputs match audio, with a controlled manner to paragraph introduced diagram comparing frequencies, the output of which is connected to the control input of the clock, and inputs - outputs to the encoder and transceiver. Figure 1 shows the setup diagram in Figure 2 - time diagrams of it 5-8 are fed to the counting input of counter 1 and the input of the zero setting of counter 16 receives a signal from the output of the driver 15 connected to the output of the amplifier of the low-frequency radio station Y. Shaper 15 generates short pulses at the moment of transition of the input sinusoidal signal (diagram 23 of figure 2) through. zero diagram 24 of figure 2). The signal from the output of the imaging unit 15 is fed to the inputs of the matching circuits 17 and 18, the second inputs of which are connected to the direct and inverse outputs of the counter 16. The counter 16. counts the number of clock pulses for the half-period of the input signal and, depending on the counter reading, the pulses from the output shaper 15 is passed through one of the 17 or 18 coincidence circuits (diagrams 27.28 of FIG. 2) and goes to the decoder 12. Thus, the pulses from the output of the shaping bodies are separated depending on the frequencies of the input signal. The decoder 12 recognizes the command Fire 1 of Figure 28 of FIG. 2), when the received combination coincides with the given code, switches the radio station to the transmission mode of the diagram 29 of Figure 2) and issues an excitation command (diagram 30 of Figure 2). When you turn on the radio to transmit a signal of frequency fn. (diagram 25 of FIG. 2) from the clock generator 13 through the frequency divider 14, in which the frequency is reduced by 8 times, nocT TiaeT to the encoder 11. The frequency fgfi | d1 diagram 31 of figure 2) passes through the encoder, in which it divides into 2 (f 1) arrives at radio station 10. When a pulse of excitation torque is received on the encoder (diagram 32, figure 2), frequency f is replaced by frequency fc, and when the signal arrives from a vertical time receiver, frequency fj changes to fg (figure 33 2). At the seismic station point, this signal is received by radio station 1 and arrives at shaper 6. The frequency separation of the signals is carried out in the same way as at the source station, i.e. at the output of the coincidence circuit 8, there are pulses of the frequency fe fe of the diagram 37 of FIG. 2), and at the output of cxei 9 of the coincidence there are pulses of the frequency ft (diagram 38 of fig. 2). The decoder 3 determines the moments of the change of these frequencies and outputs the corresponding 5 pulses of the marking of the moment of excitation and the vertical time to the recording device of the seismic station 1, diagram 39 of Fig. 2). It can be seen from the diagrams in Fig. 2 that for the normal functioning of the complex it is necessary that the frequencies of the oscillators of 4 and 13 clocks be kept equal. To monitor their frequency and enable real-time tuning of the frequencies transmitted over the communication line in accordance with the bandwidth of the radio station, the signal from the output of the low frequency amplifier of the radio station 10 is compared with the output frequency of the encoder 11 in the comparison circuit 19, and depending on their difference adjusts the frequency of the clock generator to 13 clock pulses to obtain a zero difference, and it does not matter whether this adjustment is made manually or automatically. Thus, the setting of the proposed complex is greatly simplified and its maintainability during operation is increased. The absence of elements tuned to a fixed frequency or duration in the proposed complex allows for promptly rebuilding the working tons of the complex without the use of measuring instruments. Claim 1. A method of controlling a source of seismic vibrations, which includes generating and transmitting a command signal by changing the subcarrier frequency and decoding it by determining the moments of frequency change, characterized in that, in order to simplify equipment synchronization, when determining the time of frequency change, the reference frequency is set to the frequency of the command signal and calculate the number of clock pulses for the half-period of the command signal, and the command signals are obtained by dividing the clock frequency. 2. A device for carrying out the method according to Claim 1, consisting of a communication line, command and control points, each of which contains serially connected encoder, radio station, driver, a scheme for determining the moments of frequency change, including coincidence circuits. and a decoder, characterized in paragraphs, serially connected clock pulses and a frequency divider, KOJ output of which is connected to the encoder, a clock counter, the count input of which is connected to the clock generator output, the setup input connected to a driver output, and the outputs are connected to the inputs of the matching circuits. 8 5 this comparison introduced a frequency comparison circuit, the output of which is connected to the control input of the clock generator, and the input to the outputs of the encoder and radio station. Sources of information taken into account in the examination 1, USSR Author's Certificate No. 244648, G01 V 1/26, 1968. 2. US patent number 3465286, cl. 340-15.5, 1969 (prototype). IHillMlliiHIIlllillltli z / t Zl li1 l r i i g tniiiiiiiininMinniMiniiniiniiniiniininiitiinniiiiMi / t I-1 n GTR n m n n n i-i J tl 7 25 1 251 3ai: r.4y.V I I I I I / 1 MllliriinillllllliUHIIItlllllt v.vy I I