RU2501036C1 - Altimeter - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: result is achieved owing to use of a serial delay line unit, a parallel coincidence element unit, read-only memory for a parallel delay line unit and an adder, wherein the output of the range converter is connected to the input of the serial delay line unit, having a group of outputs which is connected to a group of inputs of the parallel coincidence element unit, the input of which is connected to the output of the receiver, and the group of outputs is connected through the read-only memory to the first group of inputs of the adder, having a second group of inputs connected through the parallel delay line unit to the group of outputs of the range converter and a group of outputs connecting with a group of inputs of the indicator.

EFFECT: high accuracy of measuring altitude.

3 dwg

Description

The invention relates to the field of location technology and can be used in aircraft that determine the height to a water or earth surface. Known altimeter described in the book of Davydov and others. "Operation of radar equipment" 1990, pp. 32-35. It includes transmitting and receiving antennas, nodes that provide radiation of a frequency-modulated continuous signal and receive its reflection from a water surface or earth. Altitude is defined as the frequency difference between the radiated and reflected. However, the accuracy of determining the height is not always sufficient. Known altimeter described in the book "Radio systems" M., 1990, Yu.M. Kazarinov, pp. 355-356. It uses transmitting and receiving antennas, which have a field of view that allows determining the height, regardless of the roll available in airborne objects. The synchronizer issues a command to the pulse transmitter to emit a probe pulse, which may be of a nanosecond duration. The frequency of the radiation pulses should ensure the reception of reflected signals. Moreover, the moment of arrival of the leading edge of the reflected signals characterizes the height of the apparatus. The receiver converts the reflected electromagnetic or light energy into electrical signals. The height can be determined in the range converter by the time mismatch between the clock and the leading edge of the reflected signal. The height value is displayed on the indicator. However, the accuracy of determining the height may be insufficient without the use of complicated nodes. Using the proposed device increases the accuracy of determining the height without the use of complex nodes. This is achieved by introducing a block of consecutive delay lines, a block of parallel coincidence elements, a permanent storage device of a block of parallel delay lines and an adder, while the output of the range converter is connected to the input of a block of consecutive delay lines having a group of outputs connected to a group of inputs of a block of parallel coincidence elements, an input which is connected to the output of the receiver, and the group of outputs is connected via a read-only memory, to the first group of inputs of the adder, I have its second input group connected through the block parallel lines with a group delay range and outputs inverter group outputs, connecting with the group indicator inputs. In figure 1 and in the text the following notation:

1 - transmitting antenna

2 - receiving antenna

3 - pulse transmitter

4 - receiver

5 - synchronizer

6 - range converter

7 - block sequential delay lines

8 - block parallel elements matching

9 - read-only memory

10 - block parallel lines of delays

11 - adder

12 is an indicator, while the output of the synchronizer 5 is connected via a pulse transmitter 3 to the input of the transmitting antenna 1, and is also connected to the first input of the range converter 6 having a second input connected through the receiver 4 to the output of the receiving antenna 2 and connected to the input of the block of parallel elements matches 8, having a group of outputs and a group of inputs, respectively connected through a read-only memory 9 with a first group of inputs of an adder 11, And with a group of outputs of a block of consecutive delay lines 7, having an input, with union of a yield range 6, the group output transducer which is coupled through block 10 parallel delay lines with a second group of inputs of the adder 11 having an output group connected with the group indicator 12 inputs.

The operation of the device is as follows:

The synchronizer 5 issues a command to the pulse transmitter 3 to emit a probe pulse, which may be of a nanosecond duration. The pulse frequency provides the reception of reflected signals. In this case, the leading edge of the reflected signals is used to determine the height, regardless of the heel of the device. This is ensured by the selection of a certain beam width. The energy from the output of the pulse transmitter 3 enters the transmitting antenna 1, with which energy is radiated in the direction of the water surface or land. In spacecraft, the beam can be narrowly focused. The reflected energy enters the receiving antenna 2, which has a field of view not less than that of the antenna 1. From the output of the antenna 2, the energy enters the receiver 4, where it is converted into electrical signals. The preliminary height value is determined in the range converter 6 by the time mismatch between the clock pulse and the leading edge of the signal from the receiver. An example of a specific performance of the range converter is presented in the book Vasin V.V., Stepanov B.M. "Reference book on radiolocation", M., 1977, p. 214, Fig.9.7. Figure 2 shows an embodiment of the functional diagram of the Converter. It includes a block of matching elements 13, a counter 14, a delay line 15, a trigger 16, a delay line 17, elements or 18, or 19, and a delay line 20. From the output of the synchronizer 5, the sync pulse arrives through the first input of the converter 6, through the element or 18 to the first input of the trigger 16, setting it to a single state and to the input of the counter 14, as well as to the input of the block of successive delay lines 7. The signal from the output of the trigger enters through the delay line 17, through the element or 19, to the second input of the trigger 16, transferring its in a zero state. The signal also passes from the output of the delay line 17 through the delay line 20, through the element or 18, again to the installation of the trigger 16 in a single state and goes to the input of the counter 14, as well as to the input of the block of sequential delay lines 7. Thus, clock pulses are generated from the output of an element or 18.

The counter counts until a signal is received from the receiver that permits the information from the counter 14 to pass to the block of coincidence elements 13 to the group of inputs of the block of parallel delay lines 10, which has a group of outputs connected to the second group of inputs of the adder 11. The signal from receiver 4 also passes through the delay line 15, setting the counter 14 to its original state. The first group of inputs of the adder 11 receives a code that specifies the height values. The refinement is also due to the introduction of a block of consecutive delay lines 7, a block of parallel coincidence elements 8, and read-only memory 9. In this case, clock pulses from the converter 6 pass through a series of series-connected delay lines of block 7. The output of each delay line is connected to the input of the corresponding coincidence block parallel elements of coincidence 8. To the other input of each element receives a signal from the receiver 4. At the time of arrival of the leading edge of the signal from the receiver sra otaet corresponding coincidence circuit. Therefore, on the group of outputs of block 8 there will be a decimal code that enters the read-only memory 9, where for each value of this code a corresponding binary code is sewn up characterizing a certain refinement value that goes to the adder 11. The delay time of the block of parallel delay lines 10 is response time of the permanent storage device 9, which ensures the simultaneous arrival of codes in the adder at the time of arrival of the code from the Converter 6.

As a result of the summation, the code of the adjusted height enters the indicator 12 for display. Figure 3 shows the nodes included in blocks 7, 8, where the following notation is accepted: matching elements 21-25, delay lines 26-29.

Thus, the accuracy of determining the height depends on the number of bits in the qualifying code, that is, on the number of delay lines in block 7 and coincidence elements in block 8. The proposed device can be used to determine the height of air and space objects with the necessary accuracy without complicating the equipment. It is effective in determining the height of low-flying objects. The device can operate in the optical range. The accuracy of determining the height can be 0.3 m.

Claims (1)

An altimeter consisting of a transmitting antenna with an increased field of view, a receiving antenna, a pulse transmitter, a receiver, a synchronizer, a range converter and an indicator, where the output of the synchronizer is connected via a pulse transmitter to the input of the transmitting antenna, and also connected to the first input of the range converter having a second input connected through the receiver to the output of the receiving antenna, characterized in that a block of consecutive delay lines is inserted, a block of parallel coincidence elements, I constantly memorize its device, a block of parallel delay lines and an adder, while the output of the range converter is connected to the input of a block of sequential delay lines having a group of outputs connected through a block of parallel matching elements, the input of which is connected to the output of the receiver, and the group of outputs is connected via read-only memory with the first group of inputs of the adder having a second group of inputs connected through a block of parallel delay lines to the group of outputs of the range converter, and the group of outputs connected sculpt a group indicator inputs.

Images