US-20260126516-A1 - METHOD FOR OPTIMIZED DETECTION OF AN ENVIRONMENT OF A RADAR SYSTEM

US20260126516A1US 20260126516 A1US20260126516 A1US 20260126516A1US-20260126516-A1

Abstract

A method for optimized detection of an environment of a radar system. The steps include: transmitting a radar signal by a transmitting unit of the radar system, wherein an authentication sequence adapted to channel properties of a physical transmission channel is embedded into the transmitted radar signal; receiving a radar signal by a receiving unit of the radar system via the physical transmission channel, and accepting the radar signal received by the receiving unit of the radar system as valid if an authentication sequence contained in the received radar signal has a sufficient similarity to the adapted authentication sequence embedded in the transmitted radar signal.

Inventors

Christian Matthias Didong

Assignees

ROBERT BOSCH GMBH

Dates

Publication Date: 20260507
Application Date: 20250908
Priority Date: 20241105

Claims (20)

1 . A method for optimized detection of an environment of a radar system, comprising the following steps: transmitting a radar signal by a transmitting unit of the radar system, wherein an authentication sequence adapted to channel properties of a physical transmission channel is embedded into the transmitted radar signal; receiving a radar signal by a receiving unit of the radar system via the physical transmission channel; and accepting the radar signal received by the receiving unit of the radar system as valid when an authentication sequence contained in the received radar signal has a sufficient similarity to the authentication sequence embedded in the transmitted radar signal and adapted to the channel properties of the physical transmission channel.
2 . The method for detecting an environment of a radar system according to claim 1 , wherein the authentication sequence embedded in the transmitted radar signal is generated based on a provided random sequence.
3 . The method for detecting an environment of a radar system according to claim 2 , wherein the random sequence includes a random bit sequence that is generated by a random number generator of the radar system.
4 . The method for detecting an environment of a radar system according to claim 2 , wherein the random sequence is generated by an encryption unit of the radar system according to an encryption function.
5 . The method for detecting an environment of a radar system according to claim 2 , wherein the generated random sequence is modified using of a first algorithm according to a first specified function for generating a modified random sequence.
6 . The method for detecting an environment of a radar system according to claim 5 , wherein the generated random sequence is modified, for generating the modified random sequence, by interleaving the random sequence with further provided bits, which adapt signal properties of the authentication sequence that is embedded into the radar signal transmitted by the transmitting unit, in such a way that the authentication sequence contained within the radar signal received by the receiving unit via the physical transmission channel is more clearly recognizable.
7 . The method for detecting an environment of a radar system according to claim 6 , wherein the provided bits with which the random sequence is interleaved include a firmly specified sequence of bits or are selected according to bit sequences within the random sequence.
8 . The method for detecting an environment of a radar system according to claim 7 , wherein the random sequence includes a random bit sequence, which is divided into a plurality of groups of random bits, wherein provided bits are inserted between two consecutive groups of random bits in each case, which provided bits adapt the signal properties of the authentication sequence that is embedded into the radar signal transmitted by the transmitting unit, in such a way that the authentication sequence contained within the radar signal received by the receiving unit of the radar system via the physical transmission channel is more clearly recognizable.
9 . The method for detecting an environment of a radar system according to claim 8 , wherein the groups of random bits within the random bit sequence of the random sequence each include a certain number of random bits.
10 . The method for detecting an environment of a radar system according to claim 9 , wherein the bits inserted between two consecutive groups of random bits of the random bit sequence of the random sequence include at least one code bit sequence of a code set including different code bit sequences, which are selected according to a preceding and/or a subsequent group of random bits of the random sequence.
11 . The method for detecting an environment of a radar system according to claim 10 , wherein the bits of the at least one code bit sequence inserted between two consecutive groups of random bits of the random bit sequence of the random sequence, from the code set including different code bit sequences are selected: (i) according to channel properties of the physical transmission channel and/or (ii) according to the preceding and/or subsequent group of random bits of the random sequence.
12 . The method for detecting an environment of a radar system according to claim 10 , wherein the random bits of the preceding group of random bits and the random bits of the subsequent group of random bits each form an index, which is used for selecting the inserted code bit sequence.
13 . The method for detecting an environment of a radar system according to claim 5 , wherein a radar data packet is calculated using a second algorithm according to a second specified function based on the modified random sequence.
14 . The method for detecting an environment of a radar system according to claim 13 , wherein the calculated radar data packet is transmitted by the transmitting unit of the radar system and is temporarily stored as an internal radar data packet in a buffer unit of the radar system.
15 . The method for detecting an environment of a radar system according to claim 14 , wherein a radar data packet received by the receiving unit of the radar system is compared using a third algorithm with the internal radar data packet temporarily stored in the buffer unit, to determine whether an authentication sequence contained in the received radar data packet has a sufficient similarity to an authentication sequence contained in the temporarily stored internal radar data packet.
16 . The method for detecting an environment of a radar system according to claim 15 , wherein the radar data packet received by the receiving unit of the radar system is accepted as valid when the authentication sequence contained in the received radar data packet has a sufficient similarity to the authentication sequence contained in the temporarily stored internal radar data packet).
17 . An authentication unit for a radar system configured to accept a radar signal received by a receiving unit of the radar system via a physical transmission channel as valid when an authentication sequence contained in the received radar signal has a sufficient similarity to an authentication sequence that is embedded in a radar signal transmitted by a transmitting unit of the radar system and that is adapted to channel properties of the physical transmission channel.
18 . The authentication unit for a radar system according to claim 17 , wherein the authentication unit includes: (i) a random number generator that is configured to generate a random bit sequence as a random sequence, and/or (ii) an encryption unit that is configured to generate a random sequence according to an encryption function, wherein the authentication sequence embedded in the transmitted radar signal is generated based on the generated random sequence.
19 . The authentication unit for a radar system according to claim 18 , wherein the generated random sequence is modified, for generating a modified random sequence, by interleaving the random sequence with further provided bits, which adapt signal properties of the authentication sequence that is embedded into the radar signal transmitted by the transmitting unit, in such a way that the authentication sequence contained within the radar signal received by the receiving unit via the physical transmission channel is more clearly recognizable.
20 . The authentication unit for a radar system according to claim 18 , wherein the authentication unit includes a calculation unit that is configured to modify the generated random sequence using a first algorithm according to a first specified function for generating the modified random sequence, to calculate a radar data packet using a second algorithm according to a second specified function based on the modified random sequence, wherein the calculated radar data packet is transmitted by the transmitting unit of the radar system and is temporarily stored as an internal radar data packet in a buffer unit of the authentication unit, and wherein the calculation unit is configured to compare, using a third algorithm, a radar data packet received by the receiving unit of the radar system with the temporarily stored internal radar data packet in order to determine whether an authentication sequence contained in the received radar data packet has a sufficient similarity to an authentication sequence contained in the temporarily stored internal radar data packet.

Description

CROSS REFERENCE The present application claims the benefit under 35 U.S.C. § 119 of Germany Patent Application No. DE 10 2024 210 619.4 filed on Nov. 5, 2024, which is expressly incorporated herein by reference in its entirety. FIELD The present invention relates to a method for channel-optimized detection of an environment of a radar system and to an authentication unit for a radar system for protection against attacks by third parties on the radar system by using an authentication sequence adapted to channel properties of a transmission channel. BACKGROUND INFORMATION Radar technology is used in various areas for detecting objects in the environment by means of radio waves. The focus is on recognizing and locating objects. Depending on the radar technology and signal processing used, the distance, angle and speed of an object in the environment of the radar system can be determined. Germany Patent Application No. DE 10 2014 017 671 A1 relates to a conventional method for authenticating data packets in an open network, via which a sender and a receiver are connected to one another. The sender has a number of predefined permissible authentication numbers, wherein the sender marks a data packet by adding a permissible authentication number to the data packet. This number subsequently becomes impermissible for the sender. The sender sends the marked data packet over the network. The receiver receives the marked data packet and checks the received data packet for the presence of a permissible authentication number. The receiver discards the received data packet if a permissible authentication number is not identified in the received data packet. Conversely, the receiver accepts the received data packet for further processing if a permissible authentication number is identified in the received data packet. This number subsequently becomes impermissible for 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 and, based on characteristics of the received radar signal, information regarding the environment of the radar system can be extracted. There are various radar technologies such as a frequency-modulated carrier wave (FMCW) radar system. In addition, there are radar variants such as digital radar systems (digital radar), in which a message packet of a certain form is transmitted and the reception of the same message packet is subsequently recognized. Due to interference and noise, the received signal is then usually correlated with the transmitted message packet in order to establish a defined tolerance against transmission errors. The measured radar signals are not authenticated in conventional radar systems and can therefore be falsified by an attacker. An attacker can therefore transmit an identical signal, which is mistakenly recognized by the radar system as a reflection of its own signal and thus lead to an incorrect result regarding the environment of the radar system. For example, an object could be mistakenly recognized at a much shorter distance to the radar system or at a different speed relative to the radar system than is actually the case. Depending on the resolution of the radar image, if the object is classified based on radar data, the classification of the object can also be distorted so that, for example, a pedestrian in the environment is mistakenly recognized as a car. SUMMARY According to a first aspect, the present invention provides a method for optimized detection of an environment of a radar system. According to an example embodiment of the present invention, the method includes the steps of: transmitting a radar signal by a transmitting unit of the radar system, wherein an authentication sequence adapted to channel properties of a physical transmission channel is embedded into the transmitted radar signal;receiving a radar signal by a receiving unit of the radar system via the physical transmission channel; andaccepting the radar signal received by the receiving unit of the radar system as valid if an authentication sequence contained in the received radar signal has a sufficient similarity to the adapted authentication sequence embedded in the transmitted radar signal. A core feature of the present invention is the extension of an existing radar system in such a way that authentication sequences are built into or embedded into the radar signals, in particular in radar data packets or frames, and that, upon reception of the reflected radar signals, in particular radar data packets, the authentication sequences contained therein are compared with the temporarily stored expected authentication sequences in order to distinguish valid from invalid radar data packets. The method according to the present invention thereby prevents possible attacks on road users who use radar systems, in particular spoofing attacks and jamming attacks. A significant advantage of the method