CN113066313B - Forward traffic early warning system based on digital phased array antenna - Google Patents
Forward traffic early warning system based on digital phased array antenna Download PDFInfo
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- CN113066313B CN113066313B CN202110273955.4A CN202110273955A CN113066313B CN 113066313 B CN113066313 B CN 113066313B CN 202110273955 A CN202110273955 A CN 202110273955A CN 113066313 B CN113066313 B CN 113066313B
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- G—PHYSICS
- G08—SIGNALLING
- G08G—TRAFFIC CONTROL SYSTEMS
- G08G5/00—Traffic control systems for aircraft, e.g. air-traffic control [ATC]
- G08G5/0073—Surveillance aids
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- G—PHYSICS
- G08—SIGNALLING
- G08G—TRAFFIC CONTROL SYSTEMS
- G08G5/00—Traffic control systems for aircraft, e.g. air-traffic control [ATC]
- G08G5/0073—Surveillance aids
- G08G5/0078—Surveillance aids for monitoring traffic from the aircraft
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- G—PHYSICS
- G08—SIGNALLING
- G08G—TRAFFIC CONTROL SYSTEMS
- G08G5/00—Traffic control systems for aircraft, e.g. air-traffic control [ATC]
- G08G5/04—Anti-collision systems
Abstract
The invention discloses a forward traffic early warning system based on a digital phased array antenna, which comprises an early warning processing module, a receiving and transmitting processing module and the digital phased array antenna, wherein the digital phased array antenna is conformal with an installation shell of an airplane and comprises at least 5 antenna units; the system generates a C-mode sequence interrogation signal, forms S1, P1, P3, P4 coded pulses, forms P2 suppressed pulses using sum beam transmission formed by at least 4 antenna elements, and forms control beam transmission using at least 1 antenna element. And then receiving the C-mode sequence response pulse by using sum and difference beams formed by at least 4 antenna units to obtain a C-mode sequence response signal, and respectively obtaining the azimuth, the altitude and the distance of the target aircraft in the C mode according to the amplitude of the sum and difference beams, the C-mode sequence response signal, the C-mode inquiry and the time difference of the response. The invention can realize the collision early warning of small airplanes and reduce the installation difficulty of large and medium airplanes.
Description
Technical Field
The invention relates to the technical field of airspace monitoring and traffic early warning, in particular to a forward traffic early warning system based on a digital phased array antenna.
Background
In recent years, with the increasing of aircrafts such as small-sized, medium-sized and large-sized aircrafts, airspace is more and more crowded, and the aircrafts are in danger of air collision, so that airborne monitoring and collision prevention equipment is required to be adopted to ensure the flight safety of the aircrafts. At present, medium-sized and large-sized airplanes adopt an onboard collision avoidance system, inquire and detect a target airplane through a four-quadrant directional antenna, evaluate the threat level of the target airplane, alarm the air traffic collision threat and prompt a pilot to operate to avoid collision.
At present, an airborne collision avoidance system adopts a four-quadrant directional antenna to inquire and detect a target aircraft, and is suitable for medium-sized and large-sized transport planes, but because the diameter of the directional antenna is more than 200 mm, a proper installation position cannot be found on a small-sized aircraft, and the pneumatic performance of the small-sized aircraft is influenced even if the directional antenna is installed, the small-sized aircraft is not suitable for small-sized aircrafts such as a small unmanned aerial vehicle and a trainer, the small-sized aircraft can only adopt an air traffic control response monitoring system for early warning air collision, and because the ground-to-air monitoring has a blind area, the ground-to-air traffic control response monitoring system has no air-to-air monitoring and has high traffic early warning safety of the traffic early warning system. Meanwhile, with the increasing functions of medium and large-sized airplanes, the number of antennas to be installed is also increased, so that the installation of the four-quadrant directional antenna is more and more difficult.
Disclosure of Invention
The invention aims to provide a forward traffic early warning system based on a digital phased array antenna, which can realize the collision early warning of small airplanes and reduce the installation difficulty of large and medium airplanes.
In order to solve the technical problems, the invention adopts a technical scheme that: the forward traffic early warning system based on the digital phased array antenna comprises an early warning processing module, a transceiving processing module and the digital phased array antenna, wherein the digital phased array antenna is used for being installed on an airplane and is conformal to the installation position of the airplane, the transceiving processing module comprises an encoder, a transmitting control unit, a decoder and a receiving control unit, and the digital phased array antenna comprises at least 5 antenna units;
the early warning processing module is used for generating a C mode sequence inquiry signal in a C mode inquiry period;
the encoder is used for encoding the C-mode sequence interrogation signal to form S1, P1, P3, P4 encoding pulses or P2 suppression pulses;
the transmission control unit is used for controlling at least 4 antenna units to form a sum beam covering a predetermined angle range in the forward direction or controlling at least 1 antenna unit to form a control beam covering a 180-degree range in the forward direction, and transmitting S1, P1, P3 and P4 coded pulses through the sum beam or transmitting P2 suppressed pulses through the control beam to complete C-mode sequence interrogation;
the receiving control unit is used for controlling at least 4 antenna units to form sum beams and difference beams and receiving C-mode response pulses transmitted by a target airplane through the sum beams and the difference beams;
the decoder is used for decoding the C-mode response pulse to obtain a C-mode response signal;
the early warning processing module is also used for obtaining the azimuth of the target airplane according to the amplitude comparison of the sum and difference wave beams, obtaining the altitude of the target airplane according to the C-mode response signal, and obtaining the distance of the target airplane in the C-mode according to the time difference of C-mode inquiry and response.
Preferably, the receiving control unit is further configured to control at least 4 antenna units to form a plurality of beams outside the C-mode interrogation period, and receive the discontinuous oscillation codes and ADS-B information transmitted by the target aircraft through the plurality of beams;
the decoder is also used for decoding the intermittent oscillation codes to obtain an S mode address of the target airplane;
the early warning processing module is further used for obtaining a rough direction of the target airplane according to the amplitude values of the multiple beams and generating an S-mode roll call inquiry signal according to the rough direction of the target airplane and the S-mode address;
the encoder is also used for encoding the S-mode roll call inquiry signal to obtain P1, P2, P6 encoding pulse or P5 suppression pulse;
the emission control unit is also used for transmitting P1, P2, P6 coded pulses through the sum beam or transmitting P5 suppression pulses through the control beam so as to complete S-mode roll call inquiry;
the receiving control unit is also used for receiving S-mode response pulses transmitted by the target aircraft through sum beams and difference beams;
the decoder is also used for decoding the S-mode response pulse to obtain an S-mode roll call response signal;
the early warning processing module is further used for obtaining the azimuth of the target airplane in the S mode according to the amplitude of the sum and difference beams, obtaining the altitude of the target airplane in the S mode according to the S mode roll call response signal, and obtaining the distance of the target airplane in the S mode according to the S mode roll call inquiry and response time difference.
Preferably, the early warning processing module is further configured to perform track fusion on the ADS-B information, the azimuth, the altitude, and the distance of the target aircraft in the C mode and the azimuth, the altitude, and the distance of the target aircraft in the S mode to form a track of the target aircraft within a forward 180-degree range.
Preferably, the early warning processing module is further configured to evaluate a threat level of the target aircraft according to the track of the target aircraft, and generate an air traffic early warning prompt when the threat level of the target aircraft reaches a preset level.
Preferably, the early warning processing module is further configured to send an air traffic early warning prompt to the target aircraft through the S-mode data link, so that the target aircraft performs cooperative collision avoidance.
Preferably, the number of the digital phased array antennas is two, the two digital phased array antennas are respectively installed on the left wing and the right wing of the airplane, and the number of the receiving and sending processing modules is two and corresponds to the two sets of the digital phased array antennas respectively.
Preferably, among the beams transmitted by the at least 5 antenna units, there is 5 degrees of cross coverage between two adjacent beams, and the total coverage of all the beams ranges from-5 degrees to 185 degrees, so as to achieve forward 180 degrees seamless coverage.
Different from the prior art, the invention has the beneficial effects that: the method can be used for cooperative collision avoidance among small airplanes, small airplanes and medium and large airplanes, guarantees the flight safety of airspace, and has important social and military significance.
Drawings
Fig. 1 is a schematic block diagram of a forward traffic early warning system based on a digital phased array antenna according to an embodiment of the present invention.
Fig. 2 is a schematic block diagram of a forward traffic early warning system based on a digital phased array antenna according to another embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, belong to the protection scope of the present invention.
Referring to fig. 1, the forward traffic early warning system based on the digital phased array antenna according to the embodiment of the present invention includes an early warning processing module 1, a transceiving processing module 2, and a digital phased array antenna 3, where the digital phased array antenna 3 is used for being installed on an aircraft and is conformal to an installation location of the aircraft, the transceiving processing module 2 includes an encoder 21, a transmission control unit 22, a decoder 23, and a reception control unit 24, and the digital phased array antenna 3 includes at least 5 antenna units.
The early warning processing module 1 is used for generating a C mode sequence inquiry signal in a C mode inquiry period;
the encoder 21 is used for encoding the C-mode sequence interrogation signal to form S1, P1, P3, P4 encoding pulses or P2 suppression pulses;
the transmission control unit 22 is used for controlling at least 4 antenna units to form a sum beam covering a predetermined angle range in the forward direction or controlling at least 1 antenna unit to form a control beam covering a 180-degree range in the forward direction, and transmitting S1, P1, P3 and P4 coded pulses through the sum beam or transmitting P2 suppressed pulses through the control beam to complete C-mode sequence interrogation;
the receiving control unit 24 is used for controlling at least 4 antenna units to form sum and difference beams and receiving C-mode reply pulses transmitted by the target aircraft through the sum and difference beams;
the decoder 23 is configured to decode the C-mode response pulse to obtain a C-mode response signal;
the early warning processing module 1 is further configured to obtain the azimuth of the target aircraft in the C mode according to the amplitude of the sum and difference beams, obtain the altitude of the target aircraft in the C mode according to the C mode response signal, and obtain the distance of the target aircraft in the C mode according to the time difference between the C mode query and the response.
The time difference between the C-mode interrogation and the C-mode response is the time difference between the transmission time of the S1, P1, P3, P4 code pulse or P2 quench pulse and the reception time of the C-mode response pulse.
In this embodiment, the receiving control unit 24 is further configured to control at least 4 antenna units to form a plurality of beams outside the C-mode interrogation period, and receive the discontinuous oscillation codes and ADS-B information transmitted by the target aircraft through the plurality of beams;
the decoder 23 is further configured to decode the discontinuous oscillation code to obtain an S-mode address of the target aircraft;
the early warning processing module 1 is further configured to obtain a rough azimuth of the target aircraft according to the amplitude values of the multiple beams, and generate an S-mode roll call inquiry signal according to the rough azimuth of the target aircraft and the S-mode address;
the encoder 21 is further configured to encode the S-mode roll call query signal to obtain P1, P2, P6 encoding pulses or P5 suppression pulses;
the transmission control unit 22 is also used for transmitting P1, P2, P6 coded pulses through the sum beam or transmitting P5 suppressed pulses through the control beam to complete the S-mode roll call inquiry;
the receiving control unit 24 is further configured to receive the S-mode reply pulse transmitted by the target aircraft through the sum and difference beams;
the decoder 23 is further configured to decode the S-mode response pulse to obtain an S-mode roll call response signal;
the early warning processing module 1 is further configured to obtain the azimuth of the target aircraft in the S mode according to the amplitude of the sum and difference beams, obtain the altitude of the target aircraft in the S mode according to the S mode roll call response signal, and obtain the distance of the target aircraft in the S mode according to the time difference between the S mode roll call inquiry and the response.
The time difference between the S-mode roll call query and the response refers to the time difference between the transmission time of the P1, P2, P6 code pulse or P5 quench pulse and the reception time of the S-mode response pulse.
In order to improve the monitoring accuracy of the target aircraft, in this embodiment, the early warning processing module 1 is further configured to perform track fusion on the ADS-B information, the azimuth, the altitude, and the distance of the target aircraft in the C mode, and the azimuth, the altitude, and the distance of the target aircraft in the S mode, so as to form a track of the target aircraft within a forward 180 degrees range.
Further, the early warning processing module 1 is further configured to evaluate a threat level of the target aircraft according to the track of the target aircraft, and generate an air traffic early warning prompt when the threat level of the target aircraft reaches a preset level. The air traffic early warning prompt can include threat level, and the direction, height, distance and the like of the airplane.
When the air traffic early warning prompt is generated, the early warning processing module 1 is further configured to send the air traffic early warning prompt to the target aircraft through the S-mode data link, so that the target aircraft can cooperatively avoid collision.
In an application scene, two sets of digital phased array antennas 3 are respectively installed on the left wing and the right wing of the airplane, and two transceiving processing modules 2 are respectively corresponding to the two sets of digital phased array antennas 3. As shown in fig. 2, there are two transceiving processing modules 2, which correspond to the digital phased array antenna 3 on the left wing and the digital phased array antenna 3 on the right wing, respectively. The two sets of digital phased array antennas 3 can be mounted on the left and right wings of the aircraft in a manner that the outer shell of the aircraft is conformal.
In the embodiment, at least 5 antenna units transmit beams, the adjacent two beams have 5-degree cross coverage, and the total coverage of all beams ranges from-5 degrees to 185 degrees, so as to realize forward 180-degree seamless coverage. The total coverage of all beams ranges from-5 degrees to 185 degrees, so that the error of the width of the synthesized beam can be eliminated, and the target aircraft detection in a forward 180-degree area can be completed within 1 second.
Through the mode, the forward traffic early warning system based on the digital phased array antenna can be used as an airborne collision avoidance system of a small airplane and can be conveniently installed on medium and large airplanes, so that collision early warning of the small airplane can be realized, the installation difficulty of large and medium airplanes is reduced, the cooperative collision avoidance between the small airplane and the medium and large airplanes can be realized, the airspace flight safety is guaranteed, and the forward traffic early warning system based on the digital phased array antenna has important social and military significance.
The above description is only an example of the present application and is not intended to limit the scope of the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
Claims (7)
1. A forward traffic early warning system based on a digital phased array antenna is characterized by comprising an early warning processing module, a transceiving processing module and the digital phased array antenna, wherein the digital phased array antenna is used for being installed on an airplane and is conformal to an installation shell of the airplane, the transceiving processing module comprises an encoder, a transmitting control unit, a decoder and a receiving control unit, and the digital phased array antenna comprises at least 5 antenna units;
the early warning processing module is used for generating a C mode sequence inquiry signal in a C mode inquiry period;
the encoder is used for encoding the C-mode sequence interrogation signal to form S1, P1, P3, P4 encoding pulses or P2 suppression pulses;
the transmission control unit is used for controlling at least 4 antenna units to form a sum beam covering a predetermined angle range in the forward direction or controlling at least 1 antenna unit to form a control beam covering a 180-degree range in the forward direction, and transmitting S1, P1, P3 and P4 coded pulses through the sum beam or transmitting P2 suppressed pulses through the control beam to complete C-mode sequence interrogation;
the receiving control unit is used for controlling at least 4 antenna units to form sum beams and difference beams and receiving C-mode response pulses transmitted by a target airplane through the sum beams and the difference beams;
the decoder is used for decoding the C-mode response pulse to obtain a C-mode response signal;
the early warning processing module is further used for obtaining the azimuth of the target airplane in the C mode according to the amplitude of the sum and difference beams, obtaining the altitude of the target airplane in the C mode according to the C mode response signal, and obtaining the distance of the target airplane in the C mode according to the time difference of the C mode inquiry and response.
2. The forward traffic warning system of claim 1, wherein the receiving control unit is further configured to control at least 4 antenna units to form a plurality of beams outside the C-mode interrogation period, and receive discontinuous oscillation codes and ADS-B information transmitted by the target aircraft through the plurality of beams;
the decoder is also used for decoding the intermittent oscillation codes to obtain an S mode address of the target airplane;
the early warning processing module is further used for obtaining a rough direction of the target airplane according to the amplitude values of the multiple beams and generating an S-mode roll call inquiry signal according to the rough direction of the target airplane and the S-mode address;
the encoder is also used for encoding the S-mode roll call inquiry signal to obtain P1, P2, P6 encoding pulse or P5 suppression pulse;
the emission control unit is also used for transmitting P1, P2, P6 coded pulses through the sum beam or transmitting P5 suppression pulses through the control beam so as to complete S-mode roll call inquiry;
the receiving control unit is also used for receiving S-mode response pulses transmitted by the target aircraft through sum beams and difference beams;
the decoder is also used for decoding the S-mode response pulse to obtain an S-mode roll call response signal;
the early warning processing module is further used for obtaining the azimuth of the target airplane in the S mode according to the amplitude of the sum and difference beams, obtaining the altitude of the target airplane in the S mode according to the S mode roll call response signal, and obtaining the distance of the target airplane in the S mode according to the S mode roll call inquiry and response time difference.
3. The forward traffic warning system of claim 2, wherein the warning processing module is further configured to perform track fusion on the ADS-B information, the azimuth, altitude, and distance of the target aircraft in the C mode, and the azimuth, altitude, and distance of the target aircraft in the S mode to form a track of the target aircraft within a forward 180 degrees range.
4. The forward traffic early warning system of claim 3, wherein the early warning processing module is further configured to evaluate a threat level of the target aircraft according to a flight path of the target aircraft, and generate an air traffic early warning prompt when the threat level of the target aircraft reaches a preset level.
5. The forward traffic early warning system of claim 4, wherein the early warning processing module is further configured to send an air traffic early warning prompt to the target aircraft through an S-mode data link for cooperative collision avoidance by the target aircraft.
6. The forward traffic early warning system according to claim 1, wherein the two sets of digital phased array antennas are respectively mounted on left and right wings of the aircraft, and the two sets of transceiving processing modules respectively correspond to the two sets of digital phased array antennas.
7. The forward traffic warning system according to claim 1, wherein the beams transmitted by the at least 5 antenna units have a cross coverage of 5 degrees between two adjacent beams, and the total coverage of all the beams is from-5 degrees to 185 degrees, so as to achieve a forward 180-degree seamless coverage.
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