SU1374140A1 - Device for measuring phase shift of monostable frequencies - Google Patents

Abstract

The invention can be used in seismic surveys to measure the phase shift relative to a reference monochromatic signal. The purpose of the invention is to increase the measurement accuracy. The device contains measuring channel 1, storage device 2, recorder 3, visualization unit 4, control unit 5, generator 6, registers 7 and 8 commands and addresses, respectively, reference channel 9 and start unit 10 Introduction of the elements OR 11 and the element 12 as a result of the accumulation of information in the memory 2, it allows the variation curve, the maximum value of which with the highest probability determines the value of the measured shift time between the reference and measurement signals. 1 il. . (L

Description

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The invention relates to geophysical instrumentation and can be used in seismic surveys where a measurement of the phase shift relative to a reference monochromatic signal is required, for example for holography.

The aim of the invention is to improve the accuracy of measuring the phase shift in the background noise,.

The drawing shows a functional diagram of a device for measuring the phase shift of monostable frequencies.

The device contains measuring channel 1, accumulator 2, recorder 3 visualization block 4, control block 5, generator 6, command register 7, address register 8, reference channel 9, trigger block 10, element 11 OR element 12. But.

In this case, measuring channel 1, drive 2 and recorder 3 are connected in series, the input of the latter is combined with the input of the imaging unit. In addition, the reference channel 9, the start block 10 and the control block 5 are connected in series, the control outputs of the latter are connected to the control inputs of the command register 7 and the address register 8, the Control address output output of the latter is connected to the control address input of the accumulator 2, The information output of the measuring channel 1 is connected to the first control input of the logic element 12 I, the control command output of the command register 7 is connected to the control command inputs of the accumulator 2, measuring channel 1 and the second control The logical input element 12 I, the output of which is connected to the first control input of the logical element 11 OR, the second control input of which is connected to the control output of the address register 8, and the control output to the second control input of 10 launch. The control outputs of the control unit 5 are connected to the control inputs of the recorder 3 and the visualization unit 4, and the second control input is connected to the generator 6 o

 Measuring channel 1 is made on discrete or integral elements.

The drive 2 is a random access memory made on the memory elements with low power consumption of the series.

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K561RU2, K537RU2 and logical elements of the K56 series, K 176,

Recorder 3 is a galvanometer that reproduces information on paper.

The imaging unit 4 is based on a cathode ray tube having a digital-analog control.

The control block 5 consists of switching and logic elements „

The generator 6 is made on the basis of a quartz resonator.

The command register 7 and the address register 8 are counters with a given bit size, depending on the bit size of the drive 2,

Oporny channel 9 is made similar to the measuring channel 1

The start-up unit 10 is implemented on logical elements and performs the function of a trigger.

Logic elements 11 OR and 12 AND perform a logical function.

The device dp of measuring the phase shift of monostable frequencies works as follows.

The reference channel 9 causes a characteristic point (for example, the moment when the reference signal passes through zero) in the form of a pulse, which is registered in the start block 10. The signal from the start block 10 enters the control block 5, which sets the address register 8 to zero and gives on the control output, the time pulses from generator 6 are sent to register 7 of commands. Register of commands 7 issues a series of control serial commands to register the signal in measuring channel 1 and accumulate them in accumulator 2 On the issue of issuing a series of commands, the register 8 address switches the drive 2 to the next address. Each address switching is performed at a certain time quantization. Thus, the address register 8 counts the time intervals from the start of the record. Suppose that when polling the N address from the measuring channel 1, a pulse is outputted at the moment when the input signal passes through zero. The pulse is formed so that its duration is equal to the quantization duration & t. In this case, a pulse in the form of a positive unit will be input to drive 2 at N. The address will go to the input of logic element 12 AND, the second input of which will receive the last command of register 7 commands preceded by an address switching pulse. If the -pulse and command match, the signal from the output of the logic element 12 AND through the logic element 11 OR returns the starting block 10 to the initial state and the control block 5 turns off the supply of time pulses to the command register 7 and the address register 8. If for any reason the measuring channel

1 does not fix the zero-crossing of the input signal, then the address register 8, when polling all addresses of accumulator 2, outputs a control output signal to the logic element 1 1 OR, which from its output goes to the trigger unit 10 and sets the device to the initial state Next signal the reference channel 9 will bring it back to the working state, and the output pulse of the measuring channel 1 is summed in the accumulator- 2 with the information already accumulated at the Ny address. Repeating this process many times, which in the case of a monochromatic signal will be carried out on each phase of the signal, a signal will form in drive 2, the shape of which will depend on the ratio of the useful signal to interference. In the case when there is no interference, all the input information comes at the same address of the drive.

2 and the signal has the form of a single square pulse. With increasing interference, the base of this pulse increases, but the maximum of this pulse

 will always be to N addresses and it is used to determine the value of the phase shift o

The magnitude of the phase shift can be determined both with the help of the time marker, which is provided with the visualization unit 4, and with the help of the recording made by the recorder 3, This happens as follows. The control unit 5 includes a visualization unit 4, on the screen of which the information accumulated in the memory 2 is displayed. Setting the time marker to the maximum pulse, we obtain a count of the time interval from the beginning of the recording, which determine the amount of phase shift. If necessary, information from drive 2 can be reproduced.

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logged by registrar 3 as a graph. In this case, the registrar puts on the schedule the time stamps, which determine the time data of the required point of the schedule,

Thus, as a result of the accumulation, a variation curve arises, the maximum value (mode) of which with the highest probability determines the value of the measured time shift between the reference and measurement signals.

A device for measuring the phase shift of monostable frequencies allows, in comparison with the prototype, to improve the accuracy and, therefore, the reliability of measurements against the background of random interference by accumulating a large number of measurements.

Claims (1)

Invention Formula A device for measuring the phase shift of monostable frequencies containing measuring and reference channels, a storage unit, a trigger unit, a control unit, a command register, an address register, a recorder and a visualization unit, while the information output of the measuring channel is connected to the output of the storage device, the information output of which is connected to information inputs of the recorder and visualization unit, the information output of the reference channel is connected to the first control input of the trigger unit, the control output of which is connected to the first control control input, the second control input of which is connected to the generator output, and the control outputs of the control unit are connected to the control inputs of the command register, address register, registrar and visualization unit, control command output of the command register the inputs of the measuring channel and the feeder, the control address output of the address register is connected to the control to the whole address input of the accumulator, characterized in that, in order to increase the accuracy of the measurement of the phase shift against the background fur, it Hilti introduced logical element and an AND gate, a first control input of NAND gate 513741406 And connected to the information output element OR, the second control the measuring channel, the second control input of which is connected to the control input — from the control command output of the address register, and the control output of the command register, and the output -5 output to the second control with the first control input to the logic input of the start block.