JPH052070A - Azimuth/distance measuring device - Google Patents

Abstract

PURPOSE:To enable azimuth, distance, and reception state of an aircraft to be displayed at a ground station. CONSTITUTION:A transponder 11 transmits various kinds of pulses including a specific signal (a). In this case, a receiver gate (b) which is synchronized to the specific signal (a) is given to a data processor 19. In an interrogator 1, a signal processor 6 allows a specified response pulse (c) which indicates a reception state to be generated at a pulse generator 2 for response transmission. In the transponder 11, a plurality of antennas 17 (1-n) and a receiver 18 receive and process a response signal and a data processor 19 interprets and operates azimuth distance, and reception state data of the interrogator 1 according to a signal which is received during gating period of a receiver gate b, and then they are displayed at an indicator 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an azimuth / distance measuring device (takan device) which is a navigation assistance device.

[0002]

2. Description of the Related Art As is well known, an azimuth / distance measuring device (takan device) which is a navigation assistance device is composed of an interrogator mounted on an aircraft and a transponder installed on the ground. In the distance measuring device, as shown in FIG. 3, an interrogator 31 includes a pulse generator 32, a transmitter 3, a receiver 5, an antenna 4, a signal processor 36 and a display indicator 7, and a transponder 41 includes an antenna 1.
2, the receiver 13, the transmitter 16, the signal processor 44, and the pulse generator 15, and the aircraft (interrogator 31) emits an inquiry pulse to obtain information on the bearing and distance from the ground station (transponder 41), and the interrogator 31 The distance measurement and the azimuth measurement are performed at (signal processor 36), and the result is displayed on the display indicator 7. Hereinafter, the outline of the distance measurement and the direction measurement will be described with reference to FIGS. 4 to 9.

The transponder 41 generates and transmits various pulses as shown in FIG. First, distance measurement is performed as follows. This is similar to the ranging principle of radar. That is, the transponder 41 is connected to the interrogator 31.
Although the response pulse is transmitted in response to the inquiry pulse from, the interrogator 31 transmits the response pulse from the time when the inquiry pulse is issued, as shown in FIG. 5, because the transponder 41 is given a constant value of 50 μs. Calculate the time until receiving, and from that time a constant value (50 μs)
Measure the distance by subtracting.

Next, the azimuth measurement is performed using only the radio waves emitted from the ground station. That is, the north azimuth reference pulse (NRB), the 40-degree azimuth reference pulse (ARB), and the random pulse generated by the pulse generator 15 of the transponder 41 are radiated from the antenna 12 through the signal processor 44 and the transmitter 16. At this time, as shown in FIGS. 6 and 7, spatial modulation is performed by the combined wave of 15 Hz and 135 Hz. This modulation pattern and north direction reference pulse (NR
The positional relationship between B) and the 40-degree azimuth reference pulse (ARB) is predetermined. That is, the north direction reference pulse (NR
B) is fired when the maximum value of the spatial modulation pattern faces to the east. In addition, the 40-degree azimuth reference pulse (ARB) is
It is fired 8 times per revolution of the antenna every 40 degrees of electrical angle after the north direction reference pulse (NRB) is fired. Therefore, the azimuth can be known from the positional relationship between the spatial modulation pattern and the north azimuth reference pulse (NRB) and 40-degree azimuth reference pulse (ARB). Specifically, it is performed as shown in FIGS. 8 and 9. Note that the 40-degree azimuth reference pulse (ARB) and the 135 Hz modulated wave are equal to the north azimuth reference pulse (NRB) and 1
It is used to improve the azimuth accuracy 9 times for a 5 Hz modulated wave. This is the same as Bagna's function in the caliper.

FIGS. 8 and 9 show received waveforms and signal processing of an aircraft in the east (this position is located west of the aircraft, that is, at a position of 270 °). The interrogator 31 selects the north azimuth reference pulse (NRB) from the received waveform signal shown in FIG.
Only 15 Hz is extracted from the synthetic wave of 35 Hz by using a filter. Then, the selected north reference pulse (NR
B) Sector designation is performed every 40 ° with the electrical angle from the negative to positive zero-cross point of the signal and the 15 Hz signal as the rough azimuth. Next, in the same manner, the 40 ° azimuth reference pulse (ARB) signal and the 135 Hz signal are selected from the received waveform signal shown in FIG.
The electrical angle from the negative to the positive zero cross point of the 5 Hz signal is obtained, and the azimuth is obtained in the manner shown in FIG.

[0006]

As described above, the conventional azimuth / distance measuring device is configured for the purpose of giving the aircraft information on the azimuth and distance from the ground station. It has no means of knowing the bearing. Therefore, when checking the reception status of the interrogator at the time of flight inspection of the transponder, it is troublesome to check each wirelessly, and there is a problem that it is not possible to quickly deal with problems such as unlock notification from the pilot. ..

An object of the present invention is to provide an azimuth / distance measuring device having means for knowing the position and azimuth of an aircraft at a ground station.

[0008]

In order to achieve the above object, the azimuth / distance measuring device of the present invention has the following configuration. That is, the azimuth / distance measuring device of the present invention is an azimuth / distance measuring device including an interrogator mounted on an aircraft and a transponder installed on the ground; and transmits a reception state of a specific signal to the interrogator in response. Means; and a plurality of antennas and receivers for receiving the response transmission of the interrogator in the transponder; a data processor for analyzing the bearing and distance of the aircraft and the receiving condition from the received signal; An indicator for displaying the reception status; and the provision of the indicator.

[0009]

Next, the operation of the azimuth / distance measuring device of the present invention constructed as described above will be described. In the present invention, the transponder obtains a response signal indicating the reception state from the interrogator, analyzes and creates the azimuth and distance of the aircraft, and the reception state and displays them. Therefore, the ground station can know the direction and distance of the aircraft. As a result, in the flight inspection of the ground station,
Problem handling such as unlocking can be quickly determined. Furthermore, the safety of the navigation assistance system can be further enhanced.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an azimuth / distance measuring device according to an embodiment of the present invention. It should be noted that the same components as those of the related art are denoted by the same reference numerals. In the present invention, the interrogator 1 is similar in structure to the conventional one, but the pulse generator 2 and the signal processor 6 are slightly added, and the transponder 11 includes a plurality of antennas (1 to 1). n) 17 and receiver 18
The data processor 19 and the indicator 20 are additionally provided so that the signal processor 14 outputs a control signal (receiver gate) b to the data processor 19. Less than,
This will be described with reference to FIG.

In the transponder 11, as in the conventional case,
The pulse generator 15 generates various pulses a (see FIG. 2).
(A)), transmitted from the antenna 12 via the signal processor 14 and the transmitter 16. At that time, the signal processor 14 synchronizes with the north reference pulse (NRB) pulse and the receiver gate b.
(FIG. 2B) is formed and is output to the data processor 19.

The interrogator 1 decodes the north azimuth reference (NRB) pulse in the signal received and input by the signal processor 6 via the antenna 4 and the receiver 5, determines the reception state, and responds accordingly. A command c for generating a pulse (Fig. 2 (c)) is sent to the pulse generator 2, and a response pulse (Fig.
(C)) is generated and a response is transmitted. Here, as the response pulse, as shown in FIG. 2C, a series of three pulses is used, and the second pulse is assigned to the distance bit and the third pulse is assigned to the azimuth bit.

In the transponder 11, the 3-pulse train from the interrogator 1 is received by the plurality of antennas 17, and the data processor 19 via the receiver 18 performs the reception process of the 3-pulse train using the receiver gate b. The azimuth is analyzed by comparing the levels of. Further, the data processor 19 obtains the time until the 3-pulse train is received after the north azimuth reference (NRB) pulse is transmitted, and the distance is obtained by subtracting a predetermined processing time from the time. Further, the data processor 19 decodes the reception state and, if 3 pulse trains can be received, creates data indicating that the azimuth and distance information is normal.
If pulse trains are received, data is created that only the distance is normal. The data processor 19 outputs the direction and distance of the aircraft obtained by the above method and the information d of the reception state data to the indicator 20 for display.

Since this device has the same principle as that of the secondary radar, its coverage area is 200 to 300 NM, and the azimuth and distance of a wide range of aircraft can be known.

[0015]

As described above, according to the azimuth / distance measuring apparatus of the present invention, the transponder obtains the response signal indicating the reception state from the interrogator, and analyzes and creates the azimuth, distance and reception state of the aircraft. Since it is displayed as, it is possible to know the direction and distance of the aircraft at the ground station.
As a result, in the flight inspection of the ground station, there is an effect that the problem handling such as unlocking can be promptly determined. Furthermore, there is an effect that the safety of the navigation assistance system can be further enhanced.

[Brief description of drawings]

FIG. 1 is a configuration block diagram of an azimuth / distance measuring apparatus according to an embodiment of the present invention.

FIG. 2 is an operation time chart of the azimuth / distance measuring device according to the embodiment of the present invention.

FIG. 3 is a configuration block diagram of a conventional azimuth / distance measuring device.

FIG. 4 is a time chart of various pulses transmitted by the transponder.

FIG. 5 is an explanatory diagram of distance measurement in an interrogator.

FIG. 6 is a radiation pattern diagram of an antenna of a transponder (ground station).

FIG. 7 Radiation pattern and reference pulse (NRB, ARB)
FIG.

FIG. 8 is an explanatory diagram of direction measurement in the interrogator.

FIG. 9 is an explanatory diagram of direction measurement in the interrogator.

[Explanation of symbols]

 1 Interrogator 6 Signal Processor 11 Transponder 17 Antenna (1 to n) 18 Receiver 19 Data Processor 20 Indicator

Claims (1)

Claim: What is claimed is: 1. An azimuth / distance measuring device comprising an interrogator mounted on an aircraft and a transponder installed on the ground; a means for transmitting a response state of a reception of a specific signal to the interrogator. A plurality of antennas and receivers for receiving the response transmission of the interrogator in the transponder; a data processor for analyzing the azimuth and distance of the aircraft and the receiving condition from the received signal; An indicator for displaying the status; and an azimuth / distance measuring device provided.