DE102009035016A1 - Method for the wireless transmission of information formed from data packets - Google Patents

Abstract

The invention relates to a method for the wireless transmission of information formed from data packets from a first transmitting / receiving device (1a, 1b) provided in a missile (F1, F2) to a second transmitting / receiving device (2) provided in a control station (L). with the following steps,
a) providing an algorithm for calculating a time window information (I1a, I2) for time windows for the transmission of the data packets, the time windows being at an irregular distance from one another,
b) generating the time window information (I1a, I2) using the algorithm at the control center (L) and transferring the generated time window information (I1a, I2) to the first transceiver device (1a, 1b),
c) start of the missile (F1, F2) and transmission of data packets only within the time window defined by the time window information (I1a, I2) from the first (1a, 1b) to the second transceiver (2).

Description

The The invention relates to a method for the wireless transmission of data packets formed information from a provided in a missile first transmitting / receiving device to a second transmitting / receiving device provided in a control station.

The The invention relates in particular to the transmission of image data from a missile to a control center. For example, at the control center to act a helicopter, from which the missile launched has been.

It are jammers or so-called "jammers" known with which a wireless transmission of Information from the first to the second transceiver be disturbed can. To be against jammer preferably insensitive transmission to allow information Different methods are known. For example, that can for transmission used frequency band constantly changed become. With modern digital radio seekers it is possible, however, at the same time one Variety of frequency bands to monitor and to make a mess of it.

One Another method for mitigating the disturbance of a wireless transmission of information consists in coding the information according to the so-called "spread spectrum transmission method" and to hide in the "noise". - Meanwhile However, algorithms have been developed with which a such encoded transmission clearing up information and disturbing is.

task The invention is to the disadvantages of the prior art remove. It is intended in particular a method for wireless transmission of information formed from data packets, which possible insensitive to an attack by means of a jammer or Jammers is.

These The object is solved by the features of claim 1. Advantageous embodiments of Invention emerge from the features of claims 2 to 12th

• a) Bereitstellen eines Algorithmus zur Berechnung einer Zeitfensterinformation für Zeitfenster zur Übermittlung der Datenpakete, wobei die Zeitfenster einen unregelmäßigen Abstand voneinander aufweisen,
• b) Erzeugen der Zeitfensterinformation unter Verwendung des Algorithmus bei der Leitstelle und Übergabe der erzeugten Zeitfensterinformation an die erste Sende-/Empfangseinrichtung und
• c) Start des Flugkörpers und Übermittlung von Datenpaketen lediglich innerhalb der durch die Zeitfensterinformation definierten Zeitfenster von der ersten an die zweite Sende-/Empfangseinrichtung.

In accordance with the invention, a method for the wireless transmission of information formed from data packets from a first transmitting / receiving device provided in a missile to a second transmitting / receiving device provided in a control station is proposed with the following steps:

• a) providing an algorithm for calculating a time window information for time windows for transmitting the data packets, wherein the time windows are at an irregular distance from each other,
• b) generating the time window information using the algorithm at the control center and transferring the generated time window information to the first transceiver and
• c) start of the missile and transmission of data packets only within the time window defined by the time window information from the first to the second transceiver.

In Moving away from the prior art, the invention proposes the information not continuous, but "pulsed" or in Time windows to submit. The for transmission The time slots provided for the data packets are provided with an algorithm calculated so that their sequence is irregular or pseudo-random. Algorithms for generating pseudo-random number sequences are after known in the art. Such algorithms may be, for example a modulo function, a ZZG function or the like. From the generated pseudo-random numbers or random numbers can be a temporal Distance between two consecutive time windows are calculated. Because of the pseudorandom sequence generated by the algorithm the time window is for a misery impossible the occurrence of the next Time window to predict and disturb.

The inventive method allows an interference-insensitive transmission of information packets formed from data packets from the first transceiver to the second transmitting / receiving device.

An "information" can in According to the present invention consist of a plurality of "data packets". The "data packets" forming an "information" can be stored in several consecutive time windows are transmitted.

To In an advantageous embodiment of the invention, the calculation takes place the time window information based on a parameter which is taken from a set of different parameters. In order to can easily different pseudo-random number sequences be generated. Ie. with every use of the algorithm another pseudorandom one Sequence of time windows defined. That makes an enlightenment of thus generated coding, for example by a recording and Recording the sequence of time windows, impossible.

Advantageously, the parameter used is a time correlated with a start time of the missile and / or a datum correlated therewith. Such a parameter does not work in practice clarified. Even with knowledge of the algorithm used, it is virtually impossible to clarify the time window information thus calculated without knowing the parameter used.

To a further advantageous embodiment of the invention is with the algorithm at least a portion of the time window, a different frequency band assigned. For this purpose, the algorithm may, for example another algorithm, with the other pseudo-random numbers be generated, in turn for the use of a particular frequency band are specific. Consequently The time windows do not occur only at a random interval. It is beyond still possible, that they are assigned to a frequency band which randomly out a variety of frequency bands is selected. Also this measure contributes to that at, the process is particularly unaffected by the action of a jammer close.

To In another embodiment, the transmission of the data packets takes place in the spread band transmission method. Advantageously, the spread band transmission method is optional only when detecting a jammer used. The detection of the jammer can with a known in the prior art detection device, for example from the control center. Once a jammer has been detected, can from the control center of the normal transmission method to the Spreizbandübertragungsverfahren be switched. In the normal transmission method is advantageously the entire bandwidth of the frequency band used for transmission of user data, for example image data. there can be a large amount per unit time transmitted to user data become. In the spread band transmission method is, however, because of the required coding, the proportion of transmitted per unit time User data lower.

Especially the optional switching from a normal transmission method to a spread spectrum transmission method carry on to increase the interference resistance of the method.

To a further advantageous embodiment are in the of the first information transmitted to the second transmitting / receiving device current first spatial coordinates of the missile inserted. The allows precise monitoring of Trajectory of the missile. For this purpose can in addition to the information Data about one altitude of the missile added become.

To A particularly advantageous embodiment of the invention will become apparent the first location coordinates and from present at the control center second location coordinates a distance to the missile determined, and depending the determined distance is a transmission power to one for the transmission of Data packets from the second to the first transceiver station necessary Minimum value set. Ie. the transmission power of the second transceiver station is adapted to the distance to the first transceiver station, the transmission power as possible is kept low. This measure also makes it difficult to explain one Radio connection between the first and the second transceiver station by means of a jammer.

The first and / or second location coordinates can be determined by means of astronavigation, geländereferenzierter Navigation or using SAR images or GPS data. In particular, the use of GPS data allows easy and fast Determination of the location coordinates.

The inventive method can be performed not only unidirectionally, but also bidirectionally. For this purpose can for the wireless exchange of information between the first and the second the second transmitting / receiving device by means of the algorithm first time window information for the transmission of data packets from the first to the second transceiver station and one from the first time slot information different second time slot information for transmission of data packets from the second to the first transceiver be generated. By using the first and second timeslot information defined time windows are different from each other, it is ensured that they do not overlap.

The Generation of the first and second time windows is expediently carried out based on a common time base. For this purpose, the first and the second transmitting / receiving device a highly accurate quartz-stabilized counter included with the handover the calculated time window information is started at the same time. This allows a highly accurate generation of the respective time window.

to further increase The security of the procedure can be the transfer of the algorithm generated time window information to the first and / or second transmitting / receiving device via a Cable connection done. Such a connection is particularly secure against eavesdropping.

following Be exemplary embodiments of Invention explained in more detail with reference to the drawings. Show it:

1 schematically the transfer of a generated time window information,

2 schematically an exchange of information between a missile and a helicopter and

3 schematically generated first and second time windows.

1 schematically shows a control center L, which may be, for example, a helicopter. In the control center L several missiles F1, F2 are added, each with a first transmitting / receiving device 1a . 1b are provided. With the reference number 2 is a second transmitting / receiving device designated, which is provided in the control center L. At the transceiver stations 1a . 1b . 2 For example, they are radios that can transmit and receive on a variety of different frequency bands. Each of the transceivers 1a . 1b . 2 comprises a memory device (not shown here).

With the reference number 3 is a device for generating a time slot information called. It can be a computer which is provided with a program for generating the time window information. The device for generating the time window information 3 is over cable 4 with the first transceiver devices 1a . 1b and the second transmitting / receiving device 2 connected.

If a missile F1, F2 is to be started from the control center L, the time is used in the device for generating time window information 3 provided a first I1a and a second time slot information I2 generated. For this purpose pseudorandom number sequences are generated with an algorithm. For example, based on the generated pseudo-random number sequences, alternately the beginning of a first and a second time window are set. The time windows can each have a constant duration.

3 schematically shows first time windows t1a, which are generated on the basis of the first time window information I1a and for the transmission of data packets from the first transceiver 1a to the second transmitting / receiving device 2 be used. In 3 are designated by t2 second time windows, which are generated on the basis of the second time window information I2 and for the transmission of data packets from the second transceiver 2 to the first transmitting / receiving device 1a . 1b be used. How out 3 can be seen, the first and the second time windows occur irregularly; they do not overlap.

2 shows a further embodiment. A first missile F1 started by a control center L, here a helicopter, transmits with the first transceiver device provided therein 1a Image data D and first location coordinates K1 to the second transmitting / receiving device provided in the control center L. 2 , From the line L known second location coordinates K2, which define the position of the control center L, a distance A to the first missile F1 can be determined. It may be a transmission power of the second transceiver 2 be reduced so far that just just a secure radio connection with the first transceiver 1a is possible. For a clarification of the radio connection for a jammer is considerably more difficult. If a jammer is detected by the control center L, also with the first 1a . 1b and second transceiver 2 transmitted data packets are encrypted in Spreizbahnübertragungsverfahren. Besides, it is also possible to change the frequency bands used for information transmission at random. Again, a random frequency band sequence with the means for generating time window information 3 generated on the basis of a pseudo-random number sequence. The result will be in the first 1a and the second transceiver 2 saved. On the basis of only at the first 1a and / or second transmitting / receiving device 2 Present time window information is a particularly interference-free radio connection possible.

to Generation of the pseudorandom number sequences can use a parameter which changes constantly. Conveniently, can do that the time and date of each use of the algorithm be used to generate the pseudorandom number sequence.

LIST OF REFERENCE NUMBERS

1a, 1b

first Transmitting / receiving device

2

second Transmitting / receiving device

3

Facility for generating time window information

4

cable connection

A

distance

D

image data

F1, F2

missile

I 1a

first Time window information

I2

second Time window information

K1

first location coordinates

K2

second location coordinates

L

control center

Claims (12)

Method for the wireless transmission of Data packets formed by a in a missile (F1, F2) provided first transmitting / receiving device ( 1a . 1b ) to a second transmitting / receiving device provided in a control center (L) ( 2 comprising the steps of: a) providing an algorithm for calculating time window information (I1a, I2) for time frames for transmitting the data packets, the time slots being at an irregular distance from each other, b) generating the time slot information (I1a, I2) using the algorithm the control center (L) and transfer of the generated time window information (I1a, I2) to the first transmitting / receiving device ( 1a . 1b ), c) start of the missile (F1, F2) and transmission of data packets only within the time window defined by the time window information (I1a, I2) from the first ( 1a . 1b ) to the second transceiver device ( 2 ). Method according to claim 1, wherein the calculation of the Time window information (I1a, I2) based on a parameter takes place, which is taken from a set of different parameters. Method according to claim 2, wherein as parameter a with a start time of the missile (F1, F2) correlated time and / or a correlated date is used. Method according to one of the preceding claims, wherein with the algorithm at least a portion of the time window a different one Frequency band is assigned. Method according to one of the preceding claims, wherein the transfer of the data packets in the spread spectrum transmission method he follows. The method of claim 5, wherein the spread band transmission method optionally used only when detecting a jammer. Method according to one of the preceding claims, in which of the first ( 1a . 1b ) to the second transceiver device ( 2 ) transmitted information current first location coordinates (K1) of the missile (F1, F2) are inserted. Method according to Claim 7, wherein a distance (A) from the first local coordinates (K1) and from the second local coordinates (K2) present at the control center (L) to the missile (F1, F2) is determined and a function of the determined distance (A) Transmit power to one for transmission of data packets from the second ( 2 ) to the first transceiver station ( 1a . 1b ) required minimum value is set. The method of claim 7 or 8, wherein the first (K1) and / or second location coordinates (K2) by means of astronavigation, Intertial navigation, terrain referenced Navigation or using SAR images or GPS data be determined. Method according to one of the preceding claims, wherein for the wireless exchange of information between the first ( 1a . 1b ) and the second transceiver device ( 2 ) by means of the algorithm a first time window information (I1a) for the transmission of data packets from the first ( 1a . 1b ) to the second transceiver device ( 2 ) and a second time slot information (I1a) different from the first time slot information (I1a) ( 12 ) for transmission of data packets from the second ( 2 ) to the first transceiver device ( 1a . 1b ) be generated. Method according to one of the preceding claims, wherein the generation of the first (I1a) and second time window information (I2) is based on a common time base. Method according to one of the preceding claims, wherein the transfer of the time window information (I1a, I2) generated with the algorithm to the first ( 1a . 1b ) and / or the second transceiver device ( 2 ) via a cable connection ( 4 ) he follows.

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