RU2783257C1 - Method and system for determining the relative position of aerial vehicles - Google Patents

Abstract

FIELD: aircraft.

SUBSTANCE: invention relates to the field of navigation of aerial vehicles (AVs) and is intended for ensuring the safety of flight of a group of aerial vehicles acting jointly in difficult navigation conditions, including when the satellite radio navigation system (SRNS) fails. For this purpose, while the SRNS is in operation, navigation information is determined by each AV, transmitted and received via the information exchange channels of the AV by generating synchronisation signals in order to perform time division of the transmission and reception of the navigation information, and when the SRNS is not in operation, the time division of the transmission and reception of the navigation information are autonomously synchronised in the group of AVs, followed by transmitting and receiving signals in order to determine the relative distances between the AVs.

EFFECT: increase in the reliability of generating synchronisation signals when determining the relative position of the AV.

6 cl, 22 dwg

Description

The invention relates to the field of navigation of aircraft (LA) and is intended to ensure the safety of the flight of a group of aircraft performing joint actions in difficult navigation conditions, including when the satellite radio navigation system (SRNS) fails. Known methods for determining the relative position of an aircraft involve determining the position of each of the group of aircraft by at least one of the navigation methods and transmitting position data through information exchange channels between all aircraft and, additionally, for example, by a location method by emitting and receiving probing signals by each aircraft in order to determine the position of a neighboring aircraft [1-5]. The need for additional position determination in these patents is explained by the insufficient accuracy and reliability of determining the relative position using the navigational method.

In the mentioned patents, in order to improve the accuracy of the navigation method for determining the relative position, a satellite radio navigation system and the transmission of position data between aircraft and, additionally, due to the low reliability of satellite data, determine the relative position of neighboring aircraft using a relative position sensor built, for example, on location method.

In the patent [1], as such a sensor, a radar station for inter-aircraft navigation RLS-MSN is used, in [2] - a meter of the intensity of the high-frequency signal transmitted by a neighboring aircraft, in [3] and [4] - a millimeter radar, in [5] - a rangefinder system.

If the SRNS and data transmission had sufficient reliability required for aircraft control, additional relative position sensors would not be required. Existing SRNS such as GPS and GLONASS have the probability of issuing erroneous data 10 ^-4 per hour [6], which does not meet modern aircraft flight safety requirements. For this reason, in existing methods of relative navigation and flight control, aircraft groups use additional systems for determining relative position.

All of the patents cited assume a working SRNS. If the SRNS becomes inoperable, for example, due to the destruction of navigation satellites or due to interference in the coverage area of the aircraft group, then determining the relative position of the aircraft becomes possible only due to the operation of an additional system for determining the relative position.

The most common proposal to build an additional system for determining the relative position in patents [1-4] is the use of a radar method that allows you to determine the range and angular position of neighboring aircraft. The main disadvantage of this method (and, in general, primary radio, thermal and optical location) by the signal reflected from the target is the lack of target identification. To identify the target in aviation practice of air traffic control, the method of secondary radar is used, in which transponders of radar signals are installed on the aircraft, transmitting, in addition to the response rangefinding signal, also an information signal [7]. The use of transponders also improves the accuracy and reliability of the radar method. The disadvantage of the radar method is the complexity of implementation. For example, in [3] it is proposed to use six locators to survey the space around the aircraft.

More simple to implement is the rangefinding method [5] using transponders, which solves the problem of measuring the distance between the aircraft and the problem of identification. In this case, it is assumed that there is a system for synchronizing the operation of the aircraft equipment operating in the mode with time division of access to a common frequency communication channel [8].

According to [5, 8], the exchange of information between aircraft in a group of a small number of aircraft (up to 12) is carried out in the TDMA (Time-Division Multiple Access) mode. For this purpose, in [5], the operation of generating synchronization signals is proposed, which ensures the separation of the time of reception and transmission of navigation information. To do this, an interval time grid with a period T _c is formed, consisting of n intervals of information exchange. The signal of the beginning of the information exchange frame of all aircraft is synchronized with the SRNS time stamp (for example, a second mark). The period T _c is equal to T _c =nτ _io , where n is the number of information exchange intervals in T _c , τ _io is the duration of the information exchange interval. Information exchange intervals are assigned to each aircraft (the number of information exchange intervals corresponds to the number of aircraft).

In [9, 10], the exchange of information between aircraft in a group of an arbitrary number of aircraft is proposed, which is carried out in the STDMA (Self-Organized Time-Division Multiple Access) mode. In this case, the intervals of information exchange are not assigned to each aircraft, and to select the interval, the “interval busy/free” notification method is used, which is implemented in three stages: a request for a working interval, receiving a list of available intervals, random selection of a working interval (working intervals) from list of available intervals.

The disadvantage of this method of information exchange in the STDMA mode [9, 10] is a large time delay in the distribution of information exchange intervals when the number of aircraft changes, which is unacceptable when performing group actions of the aircraft.

A common disadvantage of the mentioned methods is that synchronization of the interval time grid is performed only by the synchronization signals of the SRNS, the failure of which leads to the inoperability of the operation of generating synchronization signals. In this case, the accuracy of the time division of information exchange in case of failure of the SRNS depends solely on the quality of the onboard time standards.

Thus, the failure of the SRNS leads, firstly, to a violation of synchronization during the exchange in the TDMA mode and, secondly, to the impossibility of determining the relative position of the aircraft due to the lack of navigation information from the SRNS.

The prototype method [11] consists in the fact that a method is proposed for determining the relative position during inter-aircraft navigation in the general case of N aircraft (AC), providing for each aircraft determining the relative position of neighboring aircraft with respect to this aircraft by the first and second methods, complex processing information about the relative position of the aircraft obtained by the first and second methods. The first method involves determining the navigation information of each aircraft by SRNS satellites, transmitting said information to neighboring aircraft and receiving navigation information of neighboring aircraft through information exchange channels by generating synchronization signals for time separation of transmission and reception of navigation information. The second method involves determining location information by transmitting and receiving probing signals by each aircraft and determining the relative ranges of neighboring aircraft.

To ensure the time separation of the information exchange signals of the first method and the time separation of the probing signals of the second method, common synchronization signals are formed for the first and second methods based on the complex processing of the time parameters of the synchronization signals of the first and second methods.

At the same time, to generate synchronization signals in the first method, the time of arrival of signals from SRNS satellites is measured. In the second method, when determining location information, additional synchronization signals are transmitted to neighboring aircraft, these signals are sequentially selected, these synchronization signals are measured, the time of arrival of these synchronization signals is measured, the said time is converted to a working time interval, and time delays are compensated based on the relative distances of neighboring aircraft.

Further, according to the times of arrival of the synchronization signals measured in the first and second methods, complex processing of the time parameters of the synchronization signals of the first and second methods is performed, for example, using Kalman filtering, and to ensure the mutual exchange of information between the aircraft, an adjustable time scale is formed on all aircraft, the setting of which is performed according to the output signals of the complex processing of the temporal parameters of the synchronization signals of the first and second methods.

A variant of the method is proposed, in which probing signals are used simultaneously as synchronization signals of the second method when determining location information.

The disadvantage of this method is that the method works only when the first method for determining the relative position of the aircraft and synchronization using satellite information and the second method for determining the relative position and synchronization using probing signals are operating simultaneously. If the SRNS stops working, then there is a gradual loss of the accuracy characteristics of the Kalman filtering, and the synchronization is broken. In addition, in a variant of the method that uses probing signals simultaneously as synchronization signals, in the absence of synchronization according to the first method, signals from different aircraft may be mixed up. Synchronization must necessarily precede the determination of the position using probing signals.

A common disadvantage of the prototype and analogues of the invention is to reduce the synchronization accuracy of the time division of the transmission and reception of navigation information with a further loss of synchronization in case of loss of SRNS performance.

The task (technical result) is to increase the reliability of the operations for generating synchronization signals when determining the relative position of the aircraft.

The problem is solved in the following way.

A method is proposed for determining the relative position in the general case of a group of aircraft (AC), consisting of a leading aircraft and neighboring aircraft, providing for each aircraft of the group to determine the relative position of all other aircraft in relation to this aircraft by the first and second methods, complex processing of information about the relative position LA obtained by the first and second methods, while the first method provides for the determination of the navigation information of each aircraft by satellites of the satellite radio navigation system (SRNS), the transmission of the mentioned information to all other aircraft and the reception of navigation information of all other aircraft through the information exchange channel by generating synchronization signals for temporary separation of the transmission and reception of navigation information, and the second method provides for each aircraft to determine the relative ranges of all other aircraft, characterized in that the determination of the relative ranges of the aircraft is carried out by transmitting and receiving navigation information transmission through a time division information exchange channel, the first and second methods are used together if the “SRNS is operable” sign is present, and if the “SRNS is inoperative” sign is present, only the second method is used, while if the “SRNS is operable” sign is present, synchronization signals are used on each aircraft based on the determination of the navigation information of the aircraft by the SRNS satellites, an information exchange frame is formed from the synchronization signals, the navigation information of the SRNS and the flight and navigation complex (PNC) is transmitted in the said frame to all other aircraft and the navigation information of the SRNS and PNC is received from all other aircraft through the channel information exchange with time division, based on the received navigation information of the SRNS and PNK, the relative distances to all other aircraft are determined and the relative coordinates of the aircraft are calculated, and in the presence of the sign "SRNS inoperative" on the leading aircraft, the synchronization signals of the leading aircraft are formed autonomously, from the mentioned signals a synchronization frame of the leading aircraft is formed, synchronization signals are formed autonomously on each adjacent aircraft, a synchronization frame of the neighboring aircraft is formed from the mentioned synchronization signals, synchronization requests from the host aircraft are transmitted sequentially in the synchronization frame of the leading aircraft to each neighboring aircraft, coinciding with the synchronization signals of the leading aircraft, in the frame synchronization of each neighbor aircraft, receive synchronization requests from the master aircraft to this neighbor aircraft, and transmit synchronization responses to the master aircraft, in the synchronization frame of the master aircraft, receive synchronization responses from each neighbor aircraft, measure the propagation delay to each neighbor aircraft, transmit propagation delay data to each neighbor aircraft, in synchronization frame of each neighboring aircraft, data on the propagation delay is received from the leading aircraft, the time position of the synchronization signals of each neighboring aircraft is corrected, then, from the synchronization signals of the leading aircraft, an information exchange frame is formed on the leading aircraft with all other aircraft, from the corrected synchronization signals of each neighboring aircraft, a frame of information exchange with all other aircraft is formed on each neighboring aircraft, in the mentioned frames, navigation information of the PNA is transmitted to all other aircraft and navigation information of the PNA is received from all other aircraft through the information exchange channel with time division , determine relative distances to all other aircraft on the basis of the received FNC navigation information and calculate the relative coordinates of the aircraft, and the complex processing of information about the relative position of the aircraft on all aircraft is carried out only on the basis of the calculated relative distances.

A variant of the method is proposed, in which an aircraft serves as the leader, which, in the mode of meeting with an aircraft - a tanker for refueling, determines its position relative to the tanker and exchanges information about the relative position with it.

A variant of the method is proposed in which an aircraft serves as the leader, carrying out the landing approach according to the SRNS data, which it exchanges with one or more ground control and correction stations, receives from them, via the information exchange channel of the first method, information that corrects measurements on the leading aircraft according to SRNS data and providing calculation of heading and glide path deviations from the landing trajectory. In this case, in the case of inoperability of the SRNS, this variant of the method provides for the construction of the landing trajectory and the calculation of deviations from it based on the measurement on the approaching aircraft of its position relative to local control and correction stations with known coordinates, equipped similarly to the approaching aircraft.

A variant of the method is proposed, in which a ground or ship point, hereinafter referred to as the leading object, serves as the leader, the position of the aircraft is determined relative to the leading object and is used for approach and landing of the aircraft on the ground airfield or the deck of the ship.

A variant of the method is proposed in which each aircraft and the leading object transmits an information package to determine the relative distances in the information exchange frame, fixes the moment of transmission and transmits the value of the transmission moment in the same information package, and all other aircraft receive the mentioned information package, fix the moments of reception of the mentioned parcels, calculate the propagation delays and offsets of the time scales of reception relative to the time scale of the transmission of the parcel, and calculate the relative distance to the aircraft or the leading object that transmitted the information parcel.

A variant of the method is proposed, in which the symbol synchronization signal of the information package in the data exchange frame is identical to the synchronization signal.

A system is proposed that implements any of the proposed methods for determining the relative position, consisting of the onboard equipment of the leading aircraft (leading object) and the onboard equipment of each of the neighboring aircraft, each of which contains an SRNS receiver connected to the SRNS receiving antenna, a data transmission line transceiver device connected with receiving and transmitting antennas of the data transmission line, a synchronization signal generator, an information exchange device, an aircraft relative coordinates calculator and a device for complex processing of information about the relative position of the aircraft, while additionally introduced into the on-board equipment of the leading aircraft (leading object) are serially connected synchronization request generator, a propagation delay meter and an “OR” circuit of the leading aircraft, as well as a relative range meter and a synchronization response demodulator, and series-connected demodulators are introduced into the on-board equipment of each of the neighboring aircraft request for synchronization and delay data, the generator of the synchronization response and the “OR” circuit of the neighboring aircraft, as well as the relative range meter, while in the on-board equipment of the leading aircraft (leading object) to the first input of the generator of synchronization signals and the first input of the device for complex processing of information about the relative position of the aircraft, a sign of SRNS operability is given, the number of “own” aircraft is supplied to the second input of the synchronization signal generator and the first input of the information exchange device, the third input of the synchronization signal generator is connected to the first output of the SRNS receiver, the second output of which is connected to the second input of the information exchange device, the first the input of the calculator of relative coordinates and with the second input of the device for complex processing of information about the relative position of the aircraft, the first, second and third outputs of the mentioned synchronization signal generator are connected respectively to the input of the synchronization request generator, with a third them and the fourth inputs of the information exchange device, the fifth input of which is supplied with PNK information, the sixth input of which is connected to the output of the transceiver device of the data transmission line and the input of the synchronization response demodulator, the output of which is connected to the second input of the propagation delay meter, the first, second, third and fourth the outputs of the mentioned information exchange device are connected respectively to the second input of the "OR" circuit of the leading aircraft, the second input of the relative coordinate calculator, the first and second inputs of the relative range meter, the output of which is connected to the third input of the relative coordinate calculator, the first and second outputs of which are connected respectively to the third and the fourth inputs of the device for complex processing of information about the relative position of the aircraft, the output of which is the output of the relative position of the onboard equipment of the leading aircraft (leading object), and the second output of the mentioned generator of synchronization requests is connected to the third input of the “OR” circuit of the leading aircraft, the output of which is connected to the input of the transceiver device of the data transmission line, and in the on-board equipment of each of the neighboring aircraft, a sign of operability is supplied to the first input of the generator of synchronization signals and the first input of the device for complex processing of information about the relative position of the aircraft SRNS, the number of "own" aircraft is supplied to the second input of the synchronization signal generator and the first input of the information exchange device, the third input of the synchronization signal generator is connected to the first output of the SRNS receiver, the second output of which is connected to the second input of the information exchange device, the first input of the relative coordinate calculator and with the second input of the device for complex processing of information about the relative position of the aircraft, the first and second outputs of the mentioned synchronization signal generator are connected respectively to the third and fourth inputs of the information exchange device, to the fifth input of which FNC information is received, the sixth input of which is connected to the output of the transceiver device of the data transmission line and to the input of the synchronization request and delay data demodulator, the first, second, third, fourth and fifth outputs of the said information exchange device are connected, respectively, to the second input of the "OR" circuit of the neighboring aircraft, the second input of the calculator of relative coordinates, the fourth input of the synchronization signal generator, the first and second inputs of the relative range meter, the output of which is connected to the third input of the calculator of the relative coordinates of the aircraft, the first and second outputs of which are connected, respectively, to the third and fourth inputs of the device for complex processing of information about the relative position of the aircraft, the output of which is the output of the relative position of the onboard equipment of the neighboring aircraft, and the output of the "OR" circuit of the neighboring aircraft is connected to the input of the transceiver device of the data transmission line.

The essence of the claimed method and system is explained with the help of Fig. 1 - Fig. 22.

On FIG. 1 shows a block diagram of the main sequence of operations of the proposed method for determining the relative position of the aircraft. The operations used in the prototype method are highlighted with rectangles with thin lines, the newly proposed operations are highlighted with rectangles with thick lines and rounded corners.

On FIG. 2 shows a block diagram of the proposed system that implements the proposed method for determining the relative position of the aircraft. The devices used in the prototype system in FIG. 2 are marked with thin-lined rectangles, the newly proposed devices are marked with thick-lined rectangles and rounded corners.

On FIG. 3 shows a block diagram of the sequence of actions according to the prototype method with the decoding of the symbols.

On FIG. 4 shows a block diagram of the prototype system with the decoding of the designations.

On FIG. 5 shows the kinematic diagram of the first determination of distance and interval.

On FIG. 6 shows a kinematic diagram of the second determination of the distance and interval.

On FIG. 7 shows the sequence diagram of JIA ₁ exchange with aircraft _i in the synchronization frame.

On FIG. Figure 8 shows the structure of the algorithm for complex information processing.

On FIG. 9 shows an example of the implementation of the transceiver device of the data transmission line of the leading aircraft 24 and the transceiver of the data transmission line of the neighboring aircraft 38 in the form of a superheterodyne transceiver.

On FIG. 10 shows an example of the implementation of the transceiver of the data line of the leading aircraft 24 and the transceiver of the data line of the neighboring aircraft 38 in the form of a direct conversion transceiver.

On FIG. 11 shows a block diagram of the generator of synchronization signals 27.

On FIG. 12 shows the timing diagrams for the operation of the generator of synchronization signals 8.

On FIG. 13 shows a block diagram of the synchronization signal generator 41.

On FIG. 14 shows the timing diagrams for the operation of the generator of synchronization signals 41.

On FIG. 15 shows a block diagram of the information exchange device 28.

On FIG. 16 is a block diagram of the communication device 42.

On FIG. 17 shows the timing diagrams of the operation of the information exchange device 28 when a data exchange frame is received in the i-th slot, explaining the formation of signals for measuring the relative range.

On FIG. 18 shows a block diagram of the synchronization request generator 33.

On FIG. 19 shows examples of the implementation of the synchronization request signal modulator in the synchronization request generator 33 and the synchronization response signal modulator in the synchronization response generator 46: a) implementation of the BPSK modulator; b) QPSK modulator implementation.

On FIG. 20 shows an example implementation of a sync response demodulator 31 and a sync request demodulator 45 as an MPSK signal demodulator.

On FIG. 21 is a block diagram of a propagation delay meter 35.

On FIG. 22 shows the structure of the signal with a temporal coding method: a) the structure of one subframe; b) the complete composition of the information signal

In FIG. 1 and FIG. 3 adopted the following designations:

1. Determination of navigation information for each aircraft from SRNS satellites. Output "c" - SRNS timestamp, output "d" - aircraft navigation information on SRNS satellites.

2. Generation of synchronization signals for time separation of transmission and reception of aircraft signals. The output "e" is the signal of the start of the information exchange frame, the output "f" is the signal of the start of the synchronization frame when the SRNS is inoperative.

3. Transmission of navigation information to all other aircraft through time division information exchange channels.

4. Reception of navigation information of all other aircraft through the channels of information exchange with time division. Output "g" - navigation information for determining the relative distances of the aircraft, output "h" - navigation information for complex processing of information about the relative position of the aircraft.

5. Determining the relative ranges of all other aircraft.

6. Complex processing of information about the relative position of the aircraft.

7. Receiving a sign of SRNS performance. Output "a" - the sign "SRNS is operational", output "c" - the sign "SRNS is inoperative".

8. Formation of a frame of information exchange with all other aircraft.

9. Calculation of the relative coordinates of the aircraft.

10. Formation of the synchronization frame of the leading aircraft.

11. Formation of a synchronization frame for each neighboring aircraft.

12. Sequential transmission of synchronization requests from the master aircraft to each neighboring aircraft.

13. Sequential reception of synchronization requests of the leading aircraft by each neighboring aircraft.

14. Sequential transmission of synchronization responses to the master aircraft by each neighboring aircraft.

15. Sequential reception of synchronization responses by the master aircraft from each neighboring aircraft.

16. Sequential measurement of propagation delays on the leading aircraft from each neighboring aircraft.

17. Serial transmission of data on propagation delays by the master aircraft to each neighboring aircraft.

18. Sequential reception of data on propagation delays from the leading LA by each neighboring LA.

19. Correction of the time position of the synchronization signals of the cyclogram of each neighboring aircraft. Output "k" - a signal for adjusting the timing of the cyclogram.

49. Determination of location information by transmitting and receiving probing signals.

On FIG. 2, the following designations are adopted:

20. Onboard equipment of the leading aircraft (leading object).

21. Airborne equipment of a neighboring aircraft.

22. SRNS receiver of the leading aircraft.

23. SRNS antenna of the leading aircraft.

24. The transceiver of the data transmission line of the leading aircraft (leading object).

25. Receiving antenna of the data transmission line of the leading aircraft (leading object).

26. Transmitting antenna of the data transmission line of the leading aircraft (leading object).

27. Lead aircraft synchronization signal generator (leading object).

28. Device for information exchange of the leading aircraft (leading object).

29. Calculator of the relative coordinates of the aircraft of the leading aircraft (leading object).

30. A device for complex processing of information about the relative position of the aircraft of the leading aircraft (leading object).

31. Demodulator of synchronization responses of the leading aircraft (leading object).

32. Scheme "OR" of the leading aircraft (leading object).

33. Synchronization request generator of the leading aircraft (leading object).

34. Relative range meter of the leading aircraft (leading object).

35. Propagation delay meter.

36. SRNS receiver of a neighboring aircraft.

37. SRNS antenna of a neighboring aircraft.

38. The transceiver of the data line of the neighboring aircraft.

39. Receiving antenna of the data transmission line of the neighboring aircraft.

40. Transmitting antenna of the data transmission line of the neighboring aircraft.

41. Synchronization signal generator of neighboring aircraft.

42. Device for information exchange of neighboring aircraft.

43. Calculator of the relative coordinates of the aircraft of the neighboring aircraft.

44. A device for complex processing of information about the relative position of an aircraft of a neighboring aircraft.

45. Demodulator request synchronization neighboring LA.

46. Neighbor aircraft synchronization response generator.

47. Relative range meter of neighboring aircraft.

48. The "OR" scheme of the neighboring aircraft.

On FIG. 4 adopted the following designations:

22. SRNS receiver.

23. SRNS antenna.

24. Data line transceiver.

25. Receiving antenna data line.

26. Transmitting antenna data line.

27. Synchronization signal generator.

28. Information exchange device.

29. Calculator of relative coordinates.

30. Device for complex processing of information about the relative position of the aircraft.

50. Receiving and transmitting radar antenna.

51. Radar system.

The block diagram of the synchronization signal generator 27 (Fig. 11) contains a - a sign of the SRNS operability, b - timestamps from the SRNS receiver 22, c - frame start pulses, d - number of "own" aircraft (transmission slot of the information exchange frame), e - sync frame pulses, e are traffic frame pulses, g are sync frame slot start pulses, h are traffic frame transmit slot start pulses, and are traffic frame receive slot start pulses).

The block diagram of the synchronization signal generator 41 (Fig. 13) contains a - a sign of the SRNS operability, b - timestamps from the SRNS receiver 36, c - timestamps from the information exchange device 42, d - the number of "own" aircraft (transmission slot of the information exchange frame ), e - frame start pulses, e - data exchange frame pulses, g - start pulses of the data exchange frame transmission slots, h - start pulses of the data exchange frame reception slots.

The block diagram of the information exchange device 28 (Fig. 15) contains a - output signals of the transceiver device 24, b - navigation information of the leading aircraft on the SRNS satellites, c - PNK information, d - pulses of the beginning of the slots for receiving the information exchange frame, d - pulses of the beginning of the slots transmission of the data exchange frame, e - the number of "own" aircraft, g - signals to the input of the "OR" circuit 32, h - information received in the data exchange frame, i - demodulated symbol synchronization signal of another aircraft in the receive slot, j - unmodulated signal symbol synchronization of "own" aircraft in the transmission slot, l - modulated symbol synchronization signal, m - information about the time of emission of the symbol synchronization signal.

The block diagram of the information exchange device 42 (Fig. 16) contains a - output signals of the transceiver device 38, b - navigation information of the neighboring aircraft on the SRNS satellites, c - PNK information, d - pulses of the beginning of the slots for receiving the information exchange frame, d - pulses of the beginning of the slots transmission of the data exchange frame, e - the number of "own" aircraft, g - signals to the input of the "OR" circuit 48, h - information received in the data exchange frame, i - demodulated symbol synchronization signal of another aircraft in the receive slot, k - unmodulated signal symbol synchronization of “own” aircraft in the transmission slot, l is a modulated symbol synchronization signal, m is information about the symbol synchronization signal emission time, n is a signal for correcting the time position of the pulses of the beginning of the information exchange frame slots.

The block diagram of the synchronization request generator 33 (Fig. 18) contains a - pulses of the beginning of the synchronization frame slots, b - number of the neighboring aircraft (ROM cell address), c - modulated synchronization request signal, d - unmodulated synchronization request signal.

On FIG. 19 the following designations are accepted di={1, -1}; Tb is the period of the binary sequence; si(t) - modulated signal.

Consider the actions of the proposed method in accordance with Fig. one.

The method includes actions common with the prototype method (see Fig. 3): determining the navigation information of each aircraft on the SRNS 1 satellites, generating synchronization signals for time separation of receiving and transmitting signals of the aircraft 2, transmitting the navigation information of the SRNS to all other aircraft through the information exchange channel with time division 3, reception of SRNS navigation information of neighboring aircraft through a time division information exchange channel 4, determination of location information using the transmission and reception of probing signals 49, determination of the relative ranges of all other aircraft 5, complex processing of information about the relative position of the aircraft 6. Operations 1-4 constitute the 1st method for determining the relative position of the aircraft, and operations 49 and 5 constitute the 2nd method.

New actions are proposed that implement the claimed method. The novelty of the method, according to Fig. 1 is that the determination of the relative ranges of the aircraft according to the second method, instead of determining the location information by transmitting and receiving probing pulses 49 (Fig. 2), is carried out by transmitting and receiving navigation information through the information exchange channel with time division 3 and 4, the first and the second methods are used together in the presence of the sign "SRNS operable" 7a, and in the presence of the sign "SRNS inoperative" 7b, only the second method is used.

In the presence of the sign "SRNS operable" 7a, the formation of synchronization signals for the time separation of transmission and reception of LA 2 signals is carried out (as in the prototype) based on the determination of the SRNS navigation information from the SRNS 1 signals, the coordinates of this aircraft from the SRNS receiver are included in the navigation information for transmission to neighboring Aircraft through the time division information exchange channel 3, and are also used for complex processing of information about the relative position of the aircraft 6. Navigation information from the SRNS of neighboring aircraft is also received through the time division information exchange channel 4, which is used in the complex processing of information about the relative position of the aircraft 6.

In the presence of the sign "SRNS inoperative" 7b on the leading aircraft, synchronization signals for the time separation of transmission and reception of navigation information 2 are formed autonomously, a synchronization frame of the master aircraft 10 is formed from these signals, on each neighboring aircraft, the mentioned synchronization signals are also formed autonomously, from the synchronization signals on neighboring aircraft, a synchronization frame 11 is formed. In the synchronization frame of the master aircraft, synchronization requests 12 are sequentially transmitted from the master aircraft to each neighboring aircraft, which coincide with the synchronization signals of the master aircraft. In the synchronization frame of each neighbor LA, the synchronization requests of the leading LA are received to this neighboring LA 13 and the synchronization responses from this neighboring LA are transmitted to the leading LA 14. In the synchronization frame of the leading LA, synchronization responses are received from each neighboring LA 15, propagation delays are measured to each neighboring LA 16 and transmission of propagation delay data to each neighboring aircraft 17. In the synchronization frame of each neighboring aircraft, propagation delay data is received from the master aircraft 18 and the timing of the synchronization signals 19 is corrected.

At the end of the synchronization frame on the leading LA, an information exchange frame is formed with all other LA 8, on each neighboring LA, an information exchange frame with all other LA 8 is formed from the corrected synchronization signals. and receiving 4 through the information exchange channel with a time division of the navigation information of the NPC of all aircraft, the relative distances to all other aircraft are determined 5. Based on the navigation information of the NCP and the relative distances, the relative coordinates of the aircraft 9 are calculated. Complex processing of information about the relative position of the aircraft on all aircraft 6 is made only on the basis of determining the relative ranges.

Let us explain in more detail the algorithms for generating and processing information in the method of Fig. one.

Determination of relative coordinates in offline mode on all aircraft based on SRNS information measured on a given aircraft and received via a data link is described in the literature [8].

The main measured parameters are the absolute coordinates of the aircraft and the components of the velocity vector. The absolute coordinates of the aircraft and the speed components are transmitted via the information exchange channel to other aircraft. On your own aircraft, this data can be used for complex information processing (CPI) in conjunction with ranging measurements. The result of the COI are estimates of the relative coordinates of the interacting aircraft of the group.

When driving an aircraft in a group, the parameters of the aircraft formation, as a rule, are set by the values of three quantities: linear interval b (distance in the traverse direction), linear distance d (distance in the direction of flight) and height difference Δh (exceeding, underestimating). These parameters are used to control the flight of an aircraft in a group, and the goal of control is to maintain their values within the specified limits [12].

There is no generally accepted unambiguous definition of distance and interval in the literature. We present two versions of this definition.

расстояния между ЛА_i и ЛА_j проецируется соответственно в

Вектор путевой скорости

ЛА_i лежащий, по определению [14], в горизонтальной плоскости, продолжается за пределы ЛА_i, линейная дистанция d определяется как проекция

на это продолжение, линейный интервал b определяется как проекция

на перпендикуляр к продолжению вектора

[13].The first definition is based on a kinematic scheme (Fig. 5) using a rectangular horizontal local coordinate system of the aircraft _i , the center O of which is located at the center of mass of the aircraft _i , the axis Ox _i is directed to the North, the axis Oy _i is located vertically, the axis Oz _i complements the system coordinates to the right. In this coordinate system, the location of aircraft _j with number j is projected onto the horizontal plane, the vector

the distance between aircraft _i and aircraft _j is projected respectively into

Ground speed vector

Aircraft _i lying, by definition [14], in the horizontal plane, continues beyond the limits of aircraft _i , the linear distance d is defined as the projection

onto this extension, the linear interval b is defined as the projection

perpendicular to the continuation of the vector

[13].

по определению является путевым углом ЛА_i, равным ПУ_i=Ψ_i+УС, где Ψ_i - угол курса ЛА_i, УС - угол сноса.Angle between axis Ox _i and vector

by definition is the track angle LA _i , equal to PU _i =Ψ _i + US, where Ψ _i - the angle of the course LA _i , US - drift angle.

Let Δx _ij , Δy _ij , Δz _ij be the coordinates of aircraft _j in the horizontal local rectangular coordinate system of aircraft _i . The rotation of the coordinate system (x _i , y _i , z _i ) around the axis Oy _i is characterized by a matrix of direction cosines equal to [15]

where PU _i =Ψ _i + US,

Ψ _i - heading angle LA _i ,

US - drift angle.

From where in the coordinate system associated with the ground speed

where Δx _ij , Δy _ij , Δz _ij are the coordinates of aircraft _j

The second option for determining the linear distance and linear interval is based on the kinematic scheme of two aircraft (Fig. 6), which uses the associated coordinate system of the aircraft _i . The beginning of the O system is located in the center of mass of the aircraft _i , the axis Oy _{i sv} lies in the plane of symmetry of the aircraft _i and is directed upwards (from the cockpit floor to the canopy), the axis Ox _{i sv} is parallel to the fuselage axis (or the chord of the wing, or the main longitudinal axis of inertia) and lies in the symmetry plane of LA _i , the Oz _i axis completes the system to the right one [14].

Let the coordinates of aircraft _j be equal to x _{icv j} , y _{icv j} , z _{icv j} in the associated coordinate system of LA _i . Linear distance, line interval and height difference can be defined as follows:

The onboard equipment of the aircraft does not allow determining these parameters by direct measurement. They can be calculated knowing the absolute coordinates of the aircraft and the angular parameters.

As a source of information about the absolute coordinates of the aircraft in the SIT system, we consider the GLONASS transceiver capable of providing data (absolute coordinates) in two coordinate systems:

- geodetic coordinate system (GCS) PZ-90: B (geodetic latitude); L (geodetic longitude); H (height) and components of the velocity vector - ν _N (northern), ν _E (eastern), ν _H (vertical);

- Cartesian geocentric coordinate system OXYZ, the center of which is aligned with the center of mass of the Earth, the OY axis is directed along the axis of rotation of the Earth towards the North Pole, the OZ axis lies in the plane of the Earth's equator and is connected with the Greenwich meridian, the OX axis complements the coordinate system to the right.

It is very difficult to directly recalculate the absolute coordinates of two aircraft into the required relative coordinates. Therefore, sequential recalculation is used:

1. Converting geodetic coordinates to geocentric (GCSC):

2. Transformation of geocentric coordinates of aircraft _i and aircraft _j into relative coordinates in the horizontal local rectangular coordinate system of each of aircraft _i and aircraft _j :

Radius at the point of location of the aircraft _i :

In formula (7) a=6378245 m is the major semi-axis of the earth ellipsoid, e ² =0.0066934 is the eccentricity of the earth ellipsoid.

With small changes in the absolute coordinates, expression (6) can be simplified:

3. The interval, distance and height difference on each of the aircraft _i , aircraft _j relative to the other aircraft are determined by expressions (1)-(3).

Thus, in offline mode, to calculate on aircraft _i the linear distance, linear interval and height difference between aircraft _i and aircraft _j , the latter must transmit via the information exchange channel to aircraft _i :

at the first definition d, b, Δh - their geocentric coordinates ϕ _i , λ _i , h _i and the true track angle PU _i ;

in the second definition, d, b, Δh are their geocentric coordinates ϕ _i , λ _i , h _i .

To implement the autonomous mode in the complete absence of SRNS signals, autonomous synchronization of the cyclogram of the system operation is carried out (Fig. 6). To do this, all aircraft before working in a group of M aircraft are assigned slot numbers i=1, ..., M (they are also aircraft numbers). The leading aircraft is assigned the number 1. The numbers i correspond to specific signals from the ensemble of autonomous synchronization signals S _i (t) with a weak cross-correlation. Weak cross-correlation is necessary for a particular aircraft to isolate “its own” signal with high probabilities of correct detection and discrimination.

If the SRNS fails, which all aircraft must be notified via other communication channels, then the procedure for autonomous synchronization of the system cyclogram, described above, begins.

, где i=2, …, М. У ЛА_i будет оценка дальности

.At the end of the synchronization frame, lead aircraft ₁ will have range estimates

, where i=2, …, M. The aircraft _i will have a range estimate

.

Synchronization can be repeated after several frames. The repetition period is determined by the instability of the reference oscillators on the aircraft used to create the sequence diagrams.

размером МхМ (i, j=1, …, М) и матрица оценок скоростей.In the traffic frame that follows the synchronization frame, each LA _i (i=1,...,M) in its i-th slot transmits in the broadcast mode ("all") a packet consisting of a symbol synchronization signal CC _i and information signal IS _i . The rest of the aircraft receive information packets. In each packet, first of all, vectors of range and speed estimates are transmitted. After the information exchange frame, all aircraft will have a matrix of range estimates

size MxM (i, j=1, ..., M) and a matrix of speed estimates.

.Tracking filters can be created on the aircraft for radial range estimates

.

The measurement of relative ranges and their rates of change is combined with information exchange. A sequence diagram is implemented with a synchronization frame and an information exchange frame, which are changed as follows.

.In slot i, LA _i sends a symbol sync signal (CC _i ), which is perceived by another LA _j as a range request. In the same slot, LA _i transmits an information signal (IS _i ) with the value of the time point on its scale, in which the symbol synchronization signal is transmitted. All other aircraft receive CC _i , IS _i and fix the moments of reception of CC _i . Estimates of all delays are calculated from them

.

на примере взаимодействия двух ЛА приведен ниже.Algorithm for generating estimates

on the example of the interaction of two aircraft is given below.

The traffic frame consists of two slots 1 and 2.

LA ₁ emits in slot 1 of frame 1 signal CC ₁ at time T _u1 of its time scale. This number LA ₁ transmits in this slot in the information message IP ₁ .

On LA ₂ receive signal CC ₁ in slot 1 of frame 1 at the time T _pr12 =T _and1 +Δt ₂ +τ ₁₂ , where Δt ₂ - scale shift LA ₂ relative to the scale LA ₁ , τ ₁₂ - signal propagation delay from LA ₁ to LA ₂ . The number T _u1 is received in the message IP ₁ .

LA ₂ emits in slot 2 frame 1 signal CC ₂ at the time T _U2 =T _U1 +T _SL +Δt ₂ , where T _SL is the duration of the slot. This number LA ₂ transmits in the information message IP ₂ .

On LA ₁ receive signal SS ₂ in slot 2 of frame 1 at the time T _PR21 =T _U1 +T _SL +τ ₂₁ where τ ₂₁ is the propagation delay from LA ₂ to LA ₁ .

As a result, on LA ₁ we obtain a system of equations with two unknowns τ ₂₁ and Δt ₂ :

T _u2 \u003d T _u1 + T _sl + Δt ₂ ,

T _pr21 \ _u003d T i1 + T _sl + τ ₂₁ ,

whose solution looks like:

с экстраполяцией назад на Т_сл на момент излучения первым ЛА и оценка сдвига шкалы ЛА₂ относительно шкалы ЛА₁.This shows that we have obtained the estimate

with extrapolation back to T _sl at the time of emission of the first LA and estimate the shift of the scale LA ₂ relative to the scale LA ₁ .

On LA ₂ we obtain a system of equations with two unknowns τ ₁₂ and Δt ₂ :

T _u2 \u003d T _u1 + T _sl + Δt ₂ ,

T _pr12 \ _u003d T i1 + T _sl + τ ₁₂ ,

whose solution looks like:

Отсюда видно, что полученная оценка

относится к моменту излучения первым ЛА с учетом смещения шкал.Since T _u2 - T _sl \u003d T _u1 + Δt ₂ , we have

This shows that the resulting estimate

refers to the moment of emission by the first aircraft, taking into account the shift of the scales.

На ЛА₂ принимают это сообщение и вычисляют оценку скорости с задержкой на слот относительно оценки дальности ЛА₂:Further, in slot 1 of frame 2, LA ₁ sends to LA ₂ a message with an estimate

LA ₂ receives this message and calculates a speed estimate with a delay per slot relative to the LA ₂ range estimate:

. На ЛА1 вычисляется та же оценка

. Далее процесс повторяется.In slot 2 of frame 2, LA ₂ sends an estimate to LA ₁

. On LA1, the same estimate is calculated

. Then the process is repeated.

The described process is presented for clarity in the form of a table.

Further, on all aircraft, the range estimates are calculated:

The process is repeated in the following frames.

The described technique applies to MLA.

Advantages of this method of measuring radial distances:

с компенсацией всех временных сдвигов шкал за время кадра;1) you can synchronize less often, because in one frame, all aircraft calculate range estimates

with compensation of all time shifts of the scales during the frame;

2) a frame for measuring ranges by the “request-response” method is not needed;

3) there are no intra-system interference inherent in the "request - response" method, i.e. an ensemble of weakly correlated signals is needed only for autonomous synchronization and information exchange;

на всех ЛА можно организовать с постоянным периодом Т_к.4) tracking range estimates

on all aircraft can be organized with a constant period T _to .

Let's consider calculation of linear distance d, linear interval b and height difference Δh offline.

For the kinematic diagram of Fig. 6 from the geometric constructions in the local horizontal coordinate system of aircraft _i it follows that when measuring the horizontal distance r _s between aircraft _i and aircraft _j

d=r _g cos ε;

b \u003d r _g sin ε,

where ε=Ψ _i -Ψ _j + KU _i + US;

Ψ _i - true heading LA _i ;

Ψ _j - true course of aircraft _j ;

KU _i - heading angle LA _i , measured on LA _j ;

US - drift angle, the same for LA _i and LA _j .

, то измеряя наклонную дальность

, на ЛА_j оценка горизонтальной дальности будет равнаIf aircraft _i sends an estimate of its height to aircraft _j

, then measuring the slant range

, on aircraft _j the estimate of the horizontal range will be equal to

.where

.

In the kinematic diagram of Fig. 6 in the associated coordinate system, we denote the angle between the axis Ox _{i sv} and the vector r through ε. This angle cannot be determined from the measurement of the range r, and therefore other navigational aids should be brought in, or a direction finder should be placed on the aircraft _j . One of the possible solutions is to measure the heading angle KU _j on LA _j on LA _i and transfer the estimate of this angle through the information exchange line to LA _j . The measurement of the heading angle KU _j can be carried out, for example, using the airborne radar LA _i .

Thus, in autonomous mode, in the frame of information exchange, aircraft _i , in addition to signals for measuring range, must be transmitted to aircraft _j at the first determination of d, b, Δh:

- true heading LA _i ;

;- height

;

In the second determination of d, b, Δh on aircraft _i , the heading angle on aircraft _j should be measured.

Distance and interval estimates, both online and offline, can be used to pilot the group's aircraft. One of the aircraft control algorithms based on data on the distance and interval to another aircraft is described in [12].

Consider the implementation of complex processing of information about the relative position of the aircraft. From the point of view of ensuring the safety of a formation flight, control of the distance between interacting aircraft is decisive, therefore, together with data on relative coordinates obtained from the measured absolute coordinates from the SRNS, it is necessary to use data from direct measurements of relative distances to all aircraft interacting with this aircraft.

However, the relative coordinates of the interacting aircraft and the relative distances are not measured simultaneously, but in accordance with the cyclograms of the SRNS receiver and the information exchange between the aircraft. In addition, the volume of information received by each aircraft, even in a small group, will be significant. For example, in a group of 6 aircraft, one subscriber receives 15 absolute coordinates, 15 components of the velocity vector and 5 relative ranges. Thus, each subscriber receives 35 measured parameters in one cycle of the system operation. It follows that the joint processing of all received information will be very laborious.

In this regard, simplified algorithms for estimating relative coordinates [8] are recommended, which consist in separate filtering of coordinate and range information. The structure of one such complex information processing algorithm is shown in Fig. eight.

Consider the operation of the proposed system for determining the relative position of the aircraft, which implements the proposed method, in accordance with Fig. 2.

System Description

The operating mode is set from the PNK, first of all, by tuning the on-board equipment of all aircraft to the same frequency from the operating frequencies of the MSN system (PNK is not shown in Fig. 2).

In addition to the operating frequency, the number of the aircraft (transmission slot) and the sign of the SRNS operability are set, which determines the operating mode - "Online" or "Autonomous". The slot number is input to the synchronization signal generators 27, 41 (not shown in Fig. 2). The SRNS operability sign is fed to the inputs of the synchronization signal generators 27, 41 and devices for complex processing of information about the relative position of the aircraft 30, 44. Further, the on-board equipment of all aircraft operates automatically without the intervention of the FPU.

In non-autonomous mode, the on-board equipment of all aircraft works the same way. The timestamp of the SRNS receivers 22, 36 on each aircraft synchronizes the synchronization signal generator, which forms the data exchange slots of the MCH system cyclogram. The SRNS receivers 22, 36 measure the coordinates and navigation parameters of their aircraft, transmit them to the information exchange devices 28, 42 and the devices for complex processing of information about the relative position of the aircraft 30, 44.

Each LA in the transmission slot allocated for it transmits through the transceiver devices of the data transmission line 24, 38 to the rest of the LA in the broadcast mode a data packet containing navigation information from its own receiver SRNS 22, 36 and from the flight and navigation complex (PNA). In addition, information is transmitted about the emission time of the information message symbol synchronization signal to provide ranging. The received information message on each of the other aircraft comes from the information exchange devices 28, 42 to the inputs of the relative range meters 34, 47 and the calculators of the relative coordinates of the aircraft 29, 43. complex processing of information about the relative position of the aircraft 30, 44 for coordinate filtering. Distance information from the relative range meters 34, 47 enters the device for complex processing of information about the relative position of the aircraft 30, 44 for ranging filtering.

In the remaining slots, the aircraft receive data packets from the remaining aircraft through the transceiver devices of the data transmission line 24, 38. According to the NCP data and data received from other aircraft, relative coordinates are calculated in the calculators of the relative coordinates of the aircraft 29, 43, and then in the complex processing devices information about the relative position of the aircraft 30, 44 is a complex processing of information with the conversion of coordinates, for example, in relative distances, intervals and height differences of the aircraft.

In offline mode, in the onboard equipment of the leading aircraft, the synchronization signal generator 27 starts the synchronization request generator 33 in turn in successive slots._i for the i-th aircraft enters through the circuit "OR" 32 to the input of the transceiver device of the data line 5 and is sent on the air (Fig. 7).

Received by the receiving antenna of the data transmission line 39 of the onboard equipment of the i-th neighboring aircraft, the modulated synchronization request of the ES _i through the transceiver of the data transmission line 38 enters the synchronization request demodulator 45 of this onboard equipment, where the moment of arrival of the demodulated ES _i is recorded. The demodulated ES _i is then fed to the input of the synchronization response shaper 46, from the output of which, after a fixed delay, the modulated synchronization response OCi is fed through the "OR" circuit 48 to the transceiver of the data transmission line 38 of the onboard equipment of the i-th aircraft and is radiated through the transmitting antenna 40 on the air .

The data link transceiver 24 of the host aircraft receives the modulated timing response OCi. From the output of this transceiver of the station, the OCi signal enters the synchronization response demodulator 31 and then to the propagation delay meter 35, which measures the time interval between the unmodulated signal ES _i and the demodulated signal OCi, generates an information package (IP _i ) with the value of this interval, which arrives to the input of the transceiver of the data line 24 and is emitted into the air.

The transceiver device of the data transmission line 38 of the _i -th aircraft receives the information package IP _i of the leading aircraft, which is input to the demodulator and decoder of data about the delay as part of the information exchange device 42. the result is fed to the input of the synchronization signal generator 41 to form the beginning of the sequence diagram of the i-th aircraft.

The synchronization signal generator 41 in the data exchange frame generates slots that are input to the data exchange device 42, in which the information exchange of the i-th aircraft is carried out similarly to working in offline mode. The difference lies in the composition of the received and transmitted information, since the SRNS receiver does not work.

The information message comes from the information exchange device 23 to the input of the relative range meter 47. Information about the distances from the relative range meter 47 enters the device for complex processing of information about the relative position of the aircraft 44 for ranging filtering. At the same time, the sign of SRNS operability disables coordinate filters.

Let us give examples of the implementation of the devices included in the system of Fig. 2.

As a receiver SRNS 22, 36 can be used any of the aviation receivers SRNS, examples of which are given, for example, in [16, p. 173, table 13.3; pp. 310-319, tab. P.4.1]. The type of antenna SRNS 23, 37 depends on the type of aircraft.

Modern data lines use broadband signals and digital signal processing. Examples of transceivers for broadband signals are given, for example, in [17]. In FIG. 9 shows a block diagram of a superheterodyne duplex transceiver [17, p. 116, fig. 3.1], in Fig. 10 shows a block diagram of a direct conversion transceiver [17, p. 144, fig. 3.10]. In the mentioned block diagrams, one antenna is used for receiving and transmitting with a duplexer. In the absence of a duplexer, two antennas are used, as in the proposed system. The type of data link antenna depends on the radio frequency band and type of aircraft. Examples of data link antennas are given, for example, in [18].

On FIG. Figures 11 and 12 show a block diagram of the generator of synchronization signals 27 and timing diagrams of its operation.

On FIG. 13 and 14 show a block diagram of the synchronization signal generator 41 and timing diagrams of its operation.

On FIG. 15 and 16 are block diagrams of information exchange devices 28 and 42, respectively. When using broadband signals, modulators and demodulators in these circuits are implemented, for example, according to the circuits of FIG. 19 and 20.

Fig. 17 explains the operation of the communication device 28 when received in an information frame and generating signals for measuring relative range.

On FIG. 18 shows a block diagram of the synchronization request generator 33.

Examples of implementation of modulators and demodulators in sync request generator 33, sync response generator 46, communication devices 28 and 42, sync response demodulator 31, and sync request demodulator 45 are shown in FIG. 19 and 20.

A block diagram of the propagation delay meter 35 is shown in FIG. 21. The encoder included in this meter can be implemented in various ways: using a discrete delay line [21, p. 71, fig. 11], on a shift register [21, p. 72, fig. 12], on a counter with a matrix [21, p. 73, fig. 12].

To transmit propagation delay information, a temporal coding method ("time-pulse modulation") is adopted in which the information value is transmitted as a time interval between the "Start" and "Stop" codes. The number of discrete values of the information interval is N=2 ^z , where z is the number of bits of the transmitted information.

(mod N), что дает возможность на приемном конце обнаруживать и исправлять одиночную ошибку, возникшую в одном из информационных подциклов. При этом "Старт" передается только в первом подцикле.On FIG. 22 shows the structure of the signal with a temporal coding method [22, p. 37, fig. one]. The whole signal contains K subcycles, and the last subcycle is a test one: for arbitrary x _i (i=1, 2,…, K-1) such x _k is always chosen so that

(mod N), which makes it possible at the receiving end to detect and correct a single error that occurred in one of the information subframes. In this case, "Start" is transmitted only in the first subcycle.

As calculators of relative coordinates 29, 43 and devices for complex processing of information about the relative position of the aircraft 30, 44, any onboard aviation computing devices can be used.

Thus, in the proposed method and system, new operations and their new combinations with known operations are introduced, related to the synchronization of the reception and transmission of information between the aircraft and determining the relative position of each aircraft in the group both during the operation of the SRNS and in the event of a possible loss of operability of the SRNS.

At the same time, it is essential that the introduction of the method of autonomous synchronization of its operation into the inter-aircraft navigation system increases the reliability and survivability of the inter-aircraft navigation system.

These operations determine the essential novelty of the proposed method.

The effectiveness of the proposed method and system is confirmed by the results of simulation digital and full-scale modeling in the development and debugging of prototypes of on-board equipment for navigation, landing and inter-aircraft navigation of advanced aircraft.

The claimed invention is promising for solving the problems of improving the reliability and survivability of promising inter-aircraft navigation systems, including when solving combat missions in the conditions of destroying SRNS satellites or jamming in areas of group aviation operations.

Thus, the novelty and usefulness of the proposed method and system follows from the above.

Literature

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Claims (6)

1. A method for determining the relative position of a group of aircraft (LA), consisting of a leading aircraft and neighboring aircraft, providing for each aircraft of the group determining the relative position of all other aircraft in relation to this aircraft by the first and second methods, complex processing of information about the relative position of the aircraft, obtained by the first and second methods, while the first method involves determining the navigation information of each aircraft by satellites of the satellite radio navigation system (SRNS), transmitting the said information to all other aircraft and receiving navigation information of all other aircraft through the information exchange channel by generating synchronization signals for time division of the transmission and receiving navigation information, and the second method provides for the determination of the relative ranges of all other aircraft for each aircraft, characterized in that the determination of the relative ranges of the aircraft is carried out by transmitting and receiving navigation information through the information channel time-division exchange, the first and second methods are used together in the presence of the "SRNS operable" sign, and in the presence of the "SRNS inoperative" sign, only the second method is used, while in the presence of the "SRNS operable" sign on each aircraft, synchronization signals are formed based on determination of aircraft navigation information by SRNS satellites, an information exchange frame is formed from the synchronization signals, navigation information of the SRNS and the flight and navigation complex (PNC) is transmitted in the said frame to all other aircraft and navigation information of the SRNS and PNC is received from all other aircraft through the information exchange channel with by time division, based on the received navigation information of the SRNS and PNK, the relative distances to all other aircraft are determined and the relative coordinates of the aircraft are calculated, and in the presence of the sign "SRNS inoperative" on the leading aircraft, the synchronization signals of the leading aircraft are formed autonomously, from the mentioned signals a synchronization frame is formed synchronization signals of the leading aircraft, synchronization signals are generated autonomously on each neighboring aircraft, a synchronization frame of the neighboring aircraft is formed from the mentioned synchronization signals, synchronization requests from the leading aircraft are transmitted sequentially in the synchronization frame of the leading aircraft to each neighboring aircraft, coinciding with the synchronization signals of the leading aircraft, in the synchronization frame of each of the neighbor aircraft receive synchronization requests of the master aircraft to this neighbor aircraft and transmit synchronization responses to the master aircraft, in the synchronization frame of the master aircraft, receive synchronization responses from each neighbor aircraft, measure the propagation delay to each neighbor aircraft, transmit propagation delay data to each neighbor aircraft, in the synchronization frame each neighboring aircraft receive data on the propagation delay from the leading aircraft, correct the time position of the synchronization signals of each neighboring aircraft, then, from the synchronization signals of the leading aircraft, an information exchange frame is formed on the leading aircraft with all other aircraft, from the of the rectified synchronization signals of each neighboring aircraft, a frame of information exchange with all other aircraft is formed on each neighboring aircraft, in the mentioned frames, navigation information of the PNA is transmitted to all other aircraft and navigation information of the PNA is received from all other aircraft through a time division information exchange channel, determined on the basis of the received navigation information PNK relative ranges to all other aircraft and calculate the relative coordinates of the aircraft, and the complex processing of information about the relative position of the aircraft on all aircraft is carried out only on the basis of the calculated relative distances. 2. The method according to claim 1, characterized in that the aircraft serves as the leader, which, in the mode of meeting with the aircraft - tanker for refueling, determines its position relative to the tanker and exchanges information with it about the relative position. 3. The method according to p. 1, characterized in that the leader is an aircraft that performs an approach according to the data that it exchanges with ground one or more local control and correction stations of the SRNS with known coordinates, equipped similarly to neighboring aircraft of the method of p. 1, while when the SRNS is operational, the approaching aircraft calculates heading and glide path deviations from the landing trajectory according to the SRNS data, and in the case of the SRNS inoperability, based on measuring its position relative to local control and corrective stations. 4. The method according to paragraphs. 1-3, characterized in that each aircraft transmits an information package to determine the relative distances in the information exchange frame, fixes the moment of transmission and transmits the value of the transmission moment in the same information package, and all other aircraft receive the said information package, fix the moments of reception of the mentioned package , calculate the propagation delays and offsets of the time scales of reception relative to the time scale of the transmission of the message, and calculate the relative distance to the aircraft that transmitted the information message. 5. The method according to paragraphs. 1-4, characterized in that a variant of the method is proposed, in which the symbol synchronization signal of the information package in the data exchange frame is identical to the synchronization signal. 6. A system that implements the method according to any one of paragraphs. 1-5, consists of the onboard equipment of the leading aircraft and the onboard equipment of each of the neighboring aircraft, each of which contains a SRNS receiver connected to the SRNS receiving antenna, a data line transceiver connected to the receiving and transmitting data line antennas, a synchronization signal generator , an information exchange device, a calculator for the relative coordinates of the aircraft and a device for complex processing of information about the relative position of the aircraft, while additionally connected in series to the on-board equipment of the leading aircraft are a synchronization request generator, a propagation delay meter and an “OR” circuit of the leading aircraft, as well as a relative range meter and a synchronization response demodulator, and serially connected synchronization request and delay data demodulator, a synchronization response generator and an “OR” circuit of the neighboring aircraft, as well as a relative x ranges, while in the on-board equipment of the leading aircraft, the first input of the synchronization signal generator and the first input of the device for complex processing of information about the relative position of the aircraft are given a sign of SRNS operability, the number of “own” aircraft is fed to the second input of the synchronization signal generator and the first input of the information exchange device , the third input of the generator of synchronization signals is connected to the first output of the SRNS receiver, the second output of which is connected to the second input of the information exchange device, the first input of the relative coordinate calculator and the second input of the device for complex processing of information about the relative position of the aircraft, the first, second and third outputs of the mentioned shaper synchronization signals are connected, respectively, to the input of the synchronization request generator, to the third and fourth inputs of the information exchange device, the fifth input of which is supplied with PNK information, the sixth input of which is connected to the output of the receiver-operator of the data transmission line feeder and the input of the synchronization response demodulator, the output of which is connected to the second input of the propagation delay meter, the first, second, third and fourth outputs of the said information exchange device are connected respectively to the second input of the "OR" circuit of the leading aircraft, the second input of the relative coordinate calculator , the first and second inputs of the relative range meter, the output of which is connected to the third input of the relative coordinate calculator, the first and second outputs of which are connected respectively to the third and fourth inputs of the device for complex processing of information about the relative position of the aircraft, the output of which is the output of the relative position of the on-board equipment of the leading aircraft , and the second output of the mentioned synchronization request generator is connected to the third input of the "OR" circuit of the leading aircraft, the output of which is connected to the input of the transceiver device of the data transmission line, and in the onboard equipment of each of neighboring aircraft, the first input of the synchronization signal generator and the first input of the device for complex processing of information about the relative position of the aircraft are given a sign of the SRNS operability, the number of “own” aircraft is supplied to the second input of the synchronization signal generator and the first input of the information exchange device, the third input of the synchronization signal generator is connected to the first output of the SRNS receiver, the second output of which is connected to the second input of the information exchange device, the first input of the relative coordinate calculator and the second input of the device for complex processing of information about the relative position of the aircraft, the first and second outputs of the said synchronization signal generator are connected respectively to the third and fourth inputs of the device information exchange, the fifth input of which is supplied with FNC information, the sixth input of which is connected to the output of the transceiver device of the data transmission line and to the input of the synchronization request demodulator and data about the hold, the first, second, third, fourth and fifth outputs of the mentioned information exchange device are connected respectively to the second input of the "OR" circuit of the neighboring aircraft, the second input of the relative coordinate calculator, the fourth input of the synchronization signal generator, the first and second inputs of the relative range meter, the output of which connected to the third input of the aircraft relative coordinates calculator, the first and second outputs of which are connected respectively to the third and fourth inputs of the device for complex processing of information about the relative position of the aircraft, the output of which is the output of the relative position of the onboard equipment of the neighboring aircraft, and the output of the "OR" circuit of the neighboring aircraft is connected with the input of the transceiver of the data line.

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