JP2883684B2 - MLS receiver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION INDUSTRIAL APPLICATION The present invention is provided on an aircraft, receives a signal from a microwave landing device (hereinafter, simply referred to as MLS), and enters and approaches the aircraft. And go-back operation
Related to MLS receiver.

2. Description of the Related Art As shown in FIG. 2, the operation of an aircraft for entering and landing and approaching and returning by MLS is usually performed by an azimuth device installed outside the end 2 of the runway 1 and the outside of the runway approach end 3 ( AZ) 4, a rear heading device (BAZ) 5, and a guide signal transmitted in a time-sharing manner from an elevation device (EL) 6 installed near the landing point on the side of the runway approach end 3, When the aircraft flies along the predetermined approach and landing route 8 and lands, and it is determined that landing is difficult for some reason, it flies along the approach and return route 8 'and performs approach and landing again.

As shown in FIG. 3, a conventional MLS receiver receives a signal transmitted from a terrestrial device by an antenna 11 and
The output 21 is received and demodulated by the reception demodulation unit 12, the demodulated output 22 is subjected to data processing in the data processing unit 13, and the output obtained by receiving the transmission signal from AZ4 input in a time division manner, the transmission signal from BAZ5 And the respective angle signals 23, 24, 25 with respect to the output that has received and the output that has received the transmission signal from EL6,
Data 26 such as the positional relationship of the ground equipment is generated, these outputs from the data processing unit 13, the automatic switching signal 28 and the manual switching signal 27 from the controller, and the DME (distance) data from the distance measuring device (DME) 7. 31, and an input / output unit 14 for transmitting a vertical deviation display output and a horizontal deviation output. In addition, EL6
The angle signal 25 with respect to the output which has received the transmission signal from is output with its sensitivity adjusted according to the distance value between the runway approaching end 3 and EL6 in the data 26.

MLS in the case of aircraft approach to landing and go-around
The operation of the receiver is as follows. That is, when the MLS guidance signal to be output to the course deviation indicator (CDI) is switched from the angle signal AZ23 to the angle signal BAZ24 in the process of the aircraft transitioning from approach landing to approaching go-around, the aircraft must be at the runway midpoint. When the distance signal 26 is located in the vicinity of 10, the distance signal 26 output based on the DME signal supplied from the distance measuring device (DME) 7, which is another device, causes the angle signal AZ23
Is switched to the output of the angle signal BAZ24.

Also, when the DME on-board device is not equipped, when the aircraft comes to the vicinity of the runway intermediate point 10 by visual inspection or the like, the BAZ manual changeover switch on the controller arranged in the cockpit is operated. From the signal of the angle signal AZ23 to the angle signal BAZ24
Was switched to the signal of

[Problem to be Solved by the Invention] When the above-mentioned DME signal is used, in addition to the MLS receiver, a DME on-board device is required, and the input of the DME data 31 and the runway intermediate There is a problem that a function for calculating the point 10 is required, and the on-board device becomes expensive.

In addition, in the manual switching, the switching point between the output from the angle signal AZ23 and the output from the angle signal BAZ24 may be largely deviated from the runway intermediate point 10, and the deviation sensitivity suddenly changes and the aircraft may follow the predetermined route. There was a problem that steering became difficult in some cases.

The present invention does not use the DME data and automatically uses only the MLS signal to automatically transmit the angle signal BAZ2 from the angle signal AZ23 near the runway midpoint.
It is an object of the present invention to provide an MLS receiver which can solve the above-mentioned problem by switching to 4.

[Means for Solving the Problems] In order to solve the above problems, the MLS receiver of the present invention receives a signal from a microwave landing device, and is used for operations of approaching and landing of the aircraft and approach and return. In the MLS receiver, a timer means for counting a predetermined period from when the received signal of the height signal transmitted from the height device disappears, and when the transmission signal is received from the azimuth device when the clock signal is counted for the predetermined period. Automatic switching means for automatically switching to a state of receiving an output signal from the rearward direction device.

The predetermined period may be a period during which the aircraft flies between the elevation device and the runway midpoint.

[Operation] In the MLS receiver of the present invention configured as described above,
After a lapse of a predetermined period from when the received signal of the elevation signal transmitted from the elevation apparatus disappears, the state is automatically switched from the transmission signal reception state from the azimuth apparatus to the transmission signal reception state from the rear azimuth apparatus. However, when the received signal of the elevation signal disappears, it is when the aircraft has passed the position corresponding to the elevation device, and after a predetermined period has elapsed from this time, by appropriately setting the predetermined period, the aircraft can run on the runway. This is when passing through the intermediate point. As a result, the transmission signal reception state from the heading device near the runway midpoint is automatically switched to the transmission signal reception state from the rear heading device, and when approaching and landing before the runway midpoint, A horizontal deviation display output based on an output signal from the azimuth device is output, and when entering the approach path, a horizontal deviation display output based on an output signal from the rear azimuth device is output.

If the predetermined period is a period during which the aircraft flies between the altitude device and the runway midpoint, even if the aircraft speed changes greatly, the rearward azimuth device will change from the reception state of the transmission signal from the azimuth device at the runway midpoint. The state is automatically switched to the transmission signal reception state from.

EXAMPLES Hereinafter, the present invention will be described with reference to Examples.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. In this case, the same components as those shown in FIG. 1 and FIG. Detailed description is omitted.

In the MLS receiver according to one embodiment of the present invention, the output 21 from the antenna 11 receives and demodulates the signal transmitted from the terrestrial device by the reception demodulation unit 12, and the demodulation output 22 is subjected to data processing in the data processing unit 13A. Angular signals 23, 24, 25 for the output that received the transmission signal from AZ4, the output that received the transmission signal from BAZ5, and the output that received the transmission signal from EL6, which were input in a time-sharing manner, and the ground equipment The data 26 such as the positional relationship of the data is generated.

On the other hand, the data processing unit 13A has a detection circuit 13a that generates an output when the angle signal EL25 becomes zero, and a timer that starts counting from a time when a detection output from the detection circuit 13a is generated and outputs a signal when a predetermined set period elapses. And an output from the clock circuit 13b is supplied as an AZ / BAZ automatic switching signal to an input / output unit 14 via an OR circuit 15 described later. The timer circuit 13b includes, for example, a counter for counting clock pulses, a setter for setting a set value, and a comparator for detecting that the count value of the counter matches the set value of the setter.

The output from the data processing unit 13A, the automatic switching signal from the controller, and the output signal from the timing circuit 13b
, And a manual switching signal from the controller is also supplied to the input / output unit 14, and the vertical deviation display output and the horizontal deviation display output are transmitted from the input / output unit 14. The configuration is as follows.

When the aircraft passes the EL9 cover 9, the angle signal EL25 becomes zero. When the angle signal EL25 becomes zero, the detection circuit 13a detects this, and generates a detection output. Calculates the time from when the detection output occurs until the aircraft reaches the runway midpoint 10 using the aircraft speed and the distance information from EL6 to AZ4 contained in the data 26, and corresponds to the calculated time The set value is set in the setting unit of the time-lapse circuit 13b. On the other hand, detection circuit 1
The counter of the aging circuit 13b starts counting clock pulses from the time when the detection output of 3a is generated. The setting value of the setting device and the count value of the counter are compared by the comparator of the time-lapse circuit 13b, and when the setting value of the setting device matches the count value of the counter, an output is generated from the comparator. This output is input to the input / output unit 14 via the OR circuit 15, and the input / output unit 14 switches from the angle signal AZ23 to the angle signal BAZ24. Therefore, a horizontal deviation display output for the angle signal BAZ24 is transmitted from the input / output unit 14.

Although the clock circuit 13b is exemplified by a counter, a setter, and a comparator, the detection circuit 13a and the clock circuit 13b
Can be configured by a normal logic circuit. Further, the calculation of the time from when the detection circuit 13a generates the detection to when the aircraft reaches the runway intermediate point 10 can be realized by a simple arithmetic circuit.

Furthermore, in the calculation of the time, in addition to the distance information from EL6 to AZ4, the data 26 includes data indicating a number of other positional relationships, and data indicating these other positional relationships. Or combined data from EL6 to AZ4
The time can be calculated by using the distance information instead of the distance information.

Further, since the aircraft speed from EL6 to AZ4 is almost constant, predetermined data may be set in the setting device of the clock circuit 13b.

[Effects of the Invention] As described above, according to the present invention, a timer means for counting a predetermined period from when a received signal of a high / low signal transmitted from a height device disappears, and the predetermined time period is counted by the timer means. When the MLS receiver is provided with automatic switching means for switching from the transmission signal reception state from the azimuth device to the transmission reception state from the backward azimuth device, the DME on-board device is not required, and the predetermined period by the timekeeping means is appropriately set. By setting, the transmission signal reception state from AZ is automatically switched to the transmission signal reception state from BAZ almost at the runway midpoint.

Also, on a runway without DME on the ground,
It is possible to accurately guide the approach and return using the transmission signal from the AZ.

Furthermore, by setting the predetermined period as a period during which the aircraft flies between the elevation device and the runway midpoint, even when the speed of the aircraft changes greatly, the AZ at the runway midpoint can be obtained.
An effect is obtained that the state is automatically switched from the transmission signal receiving state from the BAZ to the transmission signal receiving state from the BAZ.

[Brief description of the drawings]

 FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention, FIG. 2 is an explanatory diagram of MLS operation, and FIG. 3 is a block diagram showing a configuration of a conventional example. 2 ... Runway end 3 ... Runway approach end 10 ... Runway midpoint 11 ... Antenna 12 ... Reception demodulation unit 13A ... Data processing unit 13a ... Detection circuit 13b ... Timer circuit 14 ... Enter Output section

Claims (2)

(57) [Claims] 1. Receiving a signal from a microwave landing gear,
MLS used for aircraft approach and landing and approach and return operations
In the receiver, a timer means for clocking a predetermined period from when the received signal of the high / low signal transmitted from the high / low device disappears; and An MLS receiver, comprising: automatic switching means for automatically switching to a state of receiving an output signal from a device. 2. The MLS receiver according to claim 1, wherein the predetermined period is a period during which the aircraft flies between the elevation device and the runway midpoint.