CN-121995371-A - Method for optimally detecting the environment of a radar system, authentication unit and radar system

Abstract

The invention relates to a method for detecting the environment of a radar system (1) in an optimized manner, an authentication unit for a radar system, and a radar system, comprising the steps of transmitting a radar signal (RS 1) by means of a transmitting unit (2) of the radar system (1), wherein an authentication sequence (AS 1) matching the channel characteristics of a physical transmission channel is embedded in the transmitted radar signal (RS 1), receiving the radar signal (RS 2) by means of a receiving unit (3) of the radar system (1) via the physical transmission channel, and accepting (S3) the radar signal (RS 2) received by the receiving unit (3) of the radar system (1) if the authentication sequence (AS 2) contained in the received radar signal (RS 2) has sufficient similarity to the matched authentication sequence (AS 1) embedded in the transmitted radar signal (RS 1).

Inventors

• C. M. Didong

Assignees

• 罗伯特·博世有限公司

Dates

Publication Date

20260508

Application Date

20251105

Priority Date

20241105

Claims (20)

1. 1. A method for detecting the environment of a radar system (1) in an optimized manner, the method comprising the steps of: transmitting (S1) a radar signal (RS 1) by means of a transmitting unit (2) of the radar system (1), wherein an authentication sequence (AS 1) matching the channel characteristics of a physical transmission channel (PHY) is embedded in the transmitted radar signal (RS 1); Receiving (S2) a radar signal (RS 2) via the physical transmission channel (PHY) by means of a receiving unit (3) of the radar system (1), and -Accepting (S3) a radar signal (RS 2) received by a receiving unit (3) of the radar system (1) is valid if the authentication sequence (AS 2) contained in the received radar signal (RS 2) has sufficient similarity to an authentication sequence (AS 1) embedded in the transmitted radar signal (RS 1) and matching the channel characteristics of the physical transmission channel (PHY).
2. 2. The method for detecting the environment of a radar system according to claim 1, wherein the authentication sequence (AS 1) is generated based on a provided random sequence (ZS).
3. 3. The method for detecting an environment of a radar system according to claim 2, wherein the random sequence (ZS) has a random bit sequence generated by a Random Number Generator (RNG) of the radar system.
4. 4. Method for detecting the environment of a radar system according to claim 2, wherein the random sequence (ZS) is generated by an encryption unit of the radar system (1) according to an encryption function.
5. 5. Method for detecting the environment of a radar system according to any one of the preceding claims 1to 4, wherein the generated random sequence (ZS) is modified according to a first predetermined function (f) by means of a first algorithm to produce a modified random sequence (ZS).
6. 6. Method for detecting the environment of a radar system according to claim 5, wherein the generated random sequence (ZS) is modified by interleaving the random sequence (ZS) with further provided bits to produce the modified random sequence (ZS) which matches the signal characteristics of an authentication sequence (AS 1) embedded in a radar signal (RS 1) transmitted by the transmitting unit (2) in such a way that the authentication sequence (AS 2) contained within a radar signal (RS 2) received by the receiving unit (3) via the physical transmission channel (PHY) can be identified in a more unambiguous manner.
7. 7. The method for detecting the environment of a radar system according to claim 6, wherein the provided bits with which the random sequence (ZS) is interleaved comprise a fixedly predetermined sequence of bits or are selected according to a sequence of bits within the random sequence (ZS).
8. 8. Method for detecting the environment of a radar system according to claim 7, wherein the random sequence (ZS) has a random bit sequence which is divided into a plurality of random bit groups, wherein provided bits are inserted between two mutually successive random bit groups, respectively, which provided bits match the signal characteristics of an authentication sequence (AS 1) embedded in a radar signal (RS 1) transmitted by the transmitting unit (2) in such a way that the authentication sequence contained in a radar signal (RS 2) received by a receiving unit (3) of the radar system (1) via the physical transmission channel can be identified in a more unambiguous manner.
9. 9. The method for detecting an environment of a radar system according to claim 8, wherein the random bit groups within the random bit sequence of the random sequence (ZS) each comprise a specific number of random bits.
10. 10. Method for detecting the environment of a radar system according to claim 9, wherein the bits inserted between two mutually successive random bit groups of the random bit sequence of the random sequence (ZS) comprise at least one code bit sequence (C) of a Code Set (CS), the code set comprising different code bit sequences, the at least one code bit sequence being selected in dependence on a preceding random bit group of the random sequence (ZS) and/or in dependence on a subsequent random bit group of the random sequence (ZS).
11. 11. Method for detecting the environment of a radar system according to claim 10, wherein the bits of the at least one code bit sequence (C) inserted between two mutually successive random bit groups of the random bit sequence of the random sequence (ZS) are selected from a Code Set (CS) comprising different code bit sequences according to the channel characteristics of the physical transmission channel (PHY) and/or according to a preceding random bit group of the random sequence (ZS) and/or according to a subsequent random bit group of the random sequence (ZS).
12. 12. Method for detecting the environment of a radar system according to claim 10 or 11, wherein the random bits of the preceding set of random bits and the random bits of the following set of random bits respectively constitute an index for selecting the inserted code bit sequence (C).
13. 13. Method for detecting the environment of a radar system according to any one of the preceding claims 5 to 12, wherein Radar Data Packets (RDP) are calculated on the basis of the modified random sequence (ZSM) by means of a second algorithm according to a second predetermined function (g).
14. 14. Method for detecting the environment of a radar system according to claim 13, wherein the calculated Radar Data Packet (RDP) is transmitted by a transmitting unit (2) of the radar system (1) and buffered as an internal radar data packet (RDP intern ) in a buffering unit (ZSPE) of the radar system (1).
15. 15. Method for detecting the environment of a radar system according to claim 14, wherein a radar data packet (RDP Empf ) received by a receiving unit (3) of the radar system (1) is compared with an internal radar data packet (RDP intern ) buffered in the buffering unit (ZSPE) by means of a third algorithm (h) to determine whether an authentication sequence (AS 2) contained in the received radar data packet (RDP Empf ) has a sufficient similarity to an authentication sequence (AS 1) contained in the buffered internal radar data packet (RDP intern ).
16. 16. The method for detecting the environment of a radar system according to claim 15, wherein a radar data packet (RDP Empf ) received by a receiving unit (2) of the radar system (1) is accepted AS valid if the authentication sequence (AS 2) contained in the received radar data packet (RDP Empf ) has sufficient similarity to the authentication sequence (AS 1) contained in the buffered internal radar data packet (RDP intern ).
17. 17. An authentication unit (4) for a radar system (1), which is designed to accept a radar signal (RS 2) received by a receiving unit (3) of the radar system (1) via a physical transmission channel (PHY) if the authentication sequence (AS 2) contained in the received radar signal (RS 2) has a sufficient similarity to an authentication sequence (AS 1) embedded in the radar signal (RS 1) transmitted by a transmitting unit (2) of the radar system (1) and matching the channel characteristics of the physical transmission channel (PHY).
18. 18. Authentication unit for a radar system according to claim 17, wherein the authentication unit (4) comprises a Random Number Generator (RNG) designed to generate a random bit sequence AS a random sequence (ZS), and/or wherein the authentication unit (4) has an encryption unit designed to generate a random sequence (ZS) according to an encryption function, wherein the authentication sequence (AS 1) embedded in the transmitted radar signal (RS 1) is generated based on the generated random sequence (ZS).
19. 19. Authentication unit for a radar system according to claim 18, wherein the generated random sequence (ZS) is modified by interleaving the random sequence (ZS) with further provided bits to produce a modified random sequence (ZS) matching the signal characteristics of an authentication sequence (AS 1) embedded in a radar signal (RS 1) transmitted by the transmitting unit (2) in such a way that the authentication sequence (AS 2) contained within a radar signal (RS 2) received by the receiving unit (3) via the physical transmission channel (PHY) can be identified in a more unambiguous way.
20. 20. Authentication unit for a radar system according to claim 18 or 19, wherein the authentication unit (4) comprises a calculation unit (BE) designed for, Modifying the generated random sequence (ZS) according to a first predetermined function (f) by means of a first algorithm to produce said modified random sequence (ZS), -Calculating a Radar Data Packet (RDP) based on said modified random sequence (ZSM) according to a second predetermined function (g) by means of a second algorithm, Wherein the calculated radar data packet (RDP Sende ) is transmitted by the transmitting unit (2) of the radar system (1) and buffered as an internal radar data packet (RDP intern ) in a buffer unit (ZSPE) of the authentication unit (4), and Wherein the calculation unit (BE) is designed to compare the radar data packet (RDP Empf ) received by the receiving unit (3) of the radar system (1) with the buffered internal radar data packet (RDP intern ) by means of a third algorithm (h) to determine whether the authentication sequence (AS 2) contained in the received radar data packet (RDP Empf ) has sufficient similarity to the authentication sequence (AS 1) contained in the buffered internal radar data packet (RDP intern ).

Description

Method for optimally detecting the environment of a radar system, authentication unit and radar system Technical Field The invention relates to a method for detecting the environment of a radar system in a channel-optimized manner and to an authentication unit for a radar system for protecting the radar system from attacks by third parties on the radar system by using an authentication sequence that matches the channel characteristics of the transmission channel. Background Radar technology is used in different fields for detecting objects in an environment by means of radio waves. In this case, it is important to recognize and locate the object. Depending on the radar technology and the signal processing used, the distance, angle and speed of objects in the environment of the radar system can be determined. DE102014017671A1 relates to a conventional method for authenticating data packets in an open network, via which a transmitter and a receiver are connected to one another. The transmitter has a plurality of predefined allowed authentication numbers, wherein the transmitter marks the data packet in such a way that the transmitter adds an allowed authentication number to the data packet. The authentication number thus subsequently becomes impermissible to the transmitter. The transmitter transmits the marked data packet over the network. The receiver receives the marked data packet, wherein the received data packet is checked for the presence of an allowed authentication number. If no allowable authentication number is recognized in the received data packet, the receiver discards the received data packet. Otherwise, if an allowable authentication number is identified in the received data packet, the receiver accepts the received data packet for further processing. The authentication number thus subsequently becomes impermissible to the receiver. Radar systems are generally based on the principle that a reflection of a radar signal transmitted by the radar system is received again by the radar system, on the basis of the characteristics of the received radar signal, information about the environment of the radar system can be extracted. Different radar technologies exist, such as frequency modulated carrier (Frequency Modulated CARRIER WAVE, FMCW) radar systems. In addition, radar variants exist, such as digital radar systems (DIGITAL RADAR) in which a message packet of a specific form is transmitted and the reception of the same message packet is subsequently recognized. Due to interference and noise, the received signal is then typically associated with the transmitted message packet to establish a defined tolerance for transmission errors. In conventional radar systems, the measured radar signals are not authenticated, and therefore may be falsified by an attacker. An attacker may thus transmit a homophonic signal by himself, which is erroneously recognized by the radar system as a receipt of a reflection of his own signal, which in turn leads to erroneous results with regard to the environment of the radar system. For example, an object may be erroneously identified at a much shorter distance from the radar system or at a different speed relative to the radar system than the actual speed. In the case of classifying objects based on radar data, the classification of objects may also be tampered with depending on the resolution of the radar image, thereby erroneously recognizing pedestrians located in the environment as automobiles, for example. Disclosure of Invention According to a first aspect, the invention creates a method for detecting the environment of a radar system in an optimized manner, the method comprising the steps of: transmitting radar signals through a transmitting unit of the radar system, wherein an authentication sequence matched with the channel characteristics of a physical transmission channel is embedded into the transmitted radar signals; receiving radar signals via the physical transmission channel by a receiving unit of the radar system, and Accepting a radar signal received by a receiving unit of the radar system is valid if the authentication sequence contained in the received radar signal has sufficient similarity to a matched authentication sequence embedded in the transmitted radar signal. The core idea of the invention is to extend an existing radar system in such a way that an authentication sequence is built or embedded in the radar signal, in particular in a radar data packet or frame, and that in the reception of a reflected radar signal, in particular a radar data packet, the authentication sequence contained therein is compared with the cached expected authentication sequence to distinguish between valid and invalid radar data packets. Thus, the method according to the invention prevents possible attacks on traffic participants using radar systems, in particular fraud attacks (Spoofing-Angriffe) and interference attacks (Jamming-Angriffe). The main advantage of the