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JP-2026514495-A - Radar system, and method for operating the radar system

JP2026514495AJP 2026514495 AJP2026514495 AJP 2026514495AJP-2026514495-A

Abstract

The radar system has a global reference oscillator configured to generate a global reference signal, and a number of radar devices linked to the global reference oscillator. At least one of the radar devices has a local reference oscillator configured to generate a local reference signal. At least one of the radar devices has a synchronization device configured to control the local reference oscillator to synchronize it with the global reference oscillator using the global reference signal.

Inventors

  • シンドラー，ダニエル
  • ハッシュ，ユルゲン
  • フィンク，マルティン

Assignees

  • ロバート ボッシュ ゲーエムベーハー

Dates

Publication Date
20260511
Application Date
20240304
Priority Date
20230428

Claims (10)

  1. In the radar system (1a to 1d), A global reference oscillator (2) configured to generate a global reference signal, It has a number of radar devices (3a-1 to 3a-n; 3b-1 to 3b-n; 3c-1 to 3c-n; 3d-1 to 3d-n) linked to the global reference oscillator (2), At least one of the radar devices (3a-1 to 3a-n; 3b-1 to 3b-n; 3c-1 to 3c-n; 3d-1 to 3d-n) has a local reference oscillator (4) configured to generate a local reference signal, A radar system (1a to 1d) wherein at least one of the radar devices (3a-1 to 3a-n; 3b-1 to 3b-n; 3c-1 to 3c-n; 3d-1 to 3d-n) has synchronization devices (5, 6) configured to control the local reference oscillator (4) in order to synchronize the local reference oscillator (4) with the global reference oscillator (2) using the global reference signal.
  2. At least one of the radar devices (3a-1 to 3a-n; 3b-1 to 3b-n; 3c-1 to 3c-n; 3d-1 to 3d-n) has a transmitting/receiving device (9a to 9c) and a high-frequency local oscillator (7a; 7d), The radar system (1a to 1d) according to claim 1, wherein the high-frequency local oscillators (7a; 7d) are configured to generate high-frequency local oscillator signals using the local reference signals and output them to the transmitting and receiving devices (9a to 9c).
  3. The radar system (1a to 1d) according to claim 2, wherein the high-frequency local oscillators (7a; 7d) are oscillators that operate at a constant frequency at least in a localized area.
  4. The radar system (1a; 1b) according to claim 2 or 3, wherein the transmitting/receiving device (9a; 9b) has an IQ mixer (12), and the high-frequency local oscillator (7a; 7d) is configured to output a high-frequency local oscillator signal to the IQ mixer (12).
  5. The transmitting/receiving device (9c) has a chirp generator (41) for generating a chirp signal, and the chirp generator (41) has an IQ mixer (43) and a digital-to-analog converter or direct digital synthesis DDS device (45). The high-frequency local oscillators (7a; 7d) are configured to output the high-frequency local oscillator signals to the IQ mixer (43), The radar system (1c) according to claim 2 or 3, wherein the digital-to-analog converter or the DDS device (45) is configured to control the IQ mixer (43) using the local reference signal.
  6. The aforementioned high-frequency local oscillator (7d) includes a phase control loop device (51) and an IQ mixer (54). The transmitting/receiving device (9c) has a digital-to-analog converter or a direct digital synthesis (DDS) device (45), The IQ mixer (54) is placed in the feedback path of the phase control loop device (51). The radar system (1d) according to any one of the prior claims, wherein the local reference oscillator (4) is configured to output a local reference signal to the phase control loop device (51) and the digital-to-analog converter or the DDS device (45), and the output signal of the digital-to-analog converter or the DDS device (45) controls the IQ mixer (54).
  7. The local reference oscillator (4) is configured to generate a comparison time signal, The radar system (1a to 1d) according to any one of the prior claims, wherein the synchronization devices (5, 6) are configured to synchronize the local reference oscillator (4) with the global reference oscillator (2) by comparing the comparison time signal with a reference time signal generated with reference to the global reference signal.
  8. The aforementioned local reference oscillator (4) is configured to generate a comparison frequency signal, The radar system (1a to 1d) according to any one of the prior claims, wherein the synchronization devices (5, 6) are configured to synchronize the local reference oscillator (4) with the global reference oscillator (2) by comparing the comparison frequency signal with a reference frequency signal generated with reference to the global reference signal.
  9. The radar system according to any one of the prior claims (1a to 1d), wherein the local reference oscillator (4) is an oscillator that operates at least locally at a constant frequency.
  10. A method for operating a radar system (1a to 1d) having a number of radar devices (3a-1 to 3a-n; 3b-1 to 3b-n; 3c-1 to 3c-n; 3d-1 to 3d-n), wherein at least one of the radar devices (3a-1 to 3a-n; 3b-1 to 3b-n; 3c-1 to 3c-n; 3d-1 to 3d-n) has a local reference oscillator (4) configured to generate a local reference signal, and in each of the following steps, A global reference signal is generated (S1) by a global reference oscillator (2), and, Using the global reference signal, synchronize (S2) the local reference oscillator (4) of at least one of the radar devices (3a-1 to 3a-n; 3b-1 to 3b-n; 3c-1 to 3c-n; 3d-1 to 3d-n) with the global reference oscillator (2). Methods that include...

Description

This invention relates to a radar system and a method for operating a radar system. A radar sensor emits a signal that is reflected by an object through the radar channel. In a monostatic system, the reflected signal is received and evaluated by the same radar sensor to detect the distance, velocity, and angle of the radar target relative to the sensor. In a bistatic system, the reflected radar signal can also be received by a spatially separated second radar sensor. The actual distance or angle to a radar target can be calculated by referring to the known distance between each radar sensor. If the system is coherent, that is, if it should operate with a fixed phase relationship between both radar sensors, then synchronization of the respective transmit signals must be performed. This can be done by physically distributing a common local oscillator (LO) signal. When this type of LO signal distribution is not performed, the transmitted signals from each radar sensor are not correlated in terms of time or phase. In signal generation using a variable oscillator and a phase-locked loop (PLL), for example, the start time of the ramp in a frequency-modulated continuous-wave radar (FMCW) is not strictly unique. Thus, timing errors between the frequency ramp and the scanning time of the analog-to-digital converter in the receiver, as well as uncorrelated phase noise in bistatic measurements, limit the system's performance, for example, with respect to its range. From International Publication No. 2017/118621, a method for restoring the phase relationship from bistatic radar signals through signal processing is known. A radar system based on one embodiment of the present invention is shown.Figure 1 shows the reception path of the radar system illustrated in the diagram.A radar system based on another embodiment of the present invention is shown.A radar system based on another embodiment of the present invention is shown.A radar system based on another embodiment of the present invention is shown.A flowchart illustrating a method for operating a radar system according to one embodiment of the present invention is shown. In all drawings, the same components or components and devices with the same function are denoted by the same reference numeral. The numbering of the method steps is for illustrative purposes only and generally does not imply a specific chronological order. In particular, multiple method steps can be performed simultaneously. Figure 1 shows radar system 1a. Radar system 1a has a global reference oscillator 2 that generates a global reference signal. The global reference signal may include a reference time or a reference frequency. A global reference signal is provided to a number of radar devices 3a-1 through 3a-n. However, the present invention is not limited to a specific number of radar devices 3a-1 through 3a-n. Each of the radar devices 3a-1 through 3a-n is linked to the global reference oscillator 2 via its respective synchronization interface 6 for receiving a global reference signal. The control device 5 controls the local reference oscillators 4 of the corresponding radar devices 3a-1 to 3a-n, and plays a role in synchronizing the local reference oscillators 4 with the global reference oscillator 2. In this way, the control device 5 and the synchronization interface 6 constitute a synchronization device. The reference oscillator 4 generates a local reference signal. The control device 5 generates a control signal for the local reference oscillator 4 by comparing the local reference signal with the global reference signal. The local reference oscillator 4 is affected as a result and begins to operate in synchronization with the global reference oscillator 2. In this way, all radar devices 3a-1 through 3a-n can access the global reference oscillator 2, and consequently, their local reference signals become synchronized. The local reference oscillator 4 can generate a reference signal having a substantially constant frequency, for example, within a predetermined time range. In the following description, only one radar system 3a-1 will be discussed; however, the other radar systems 3a-2 through 3a-n may be configured identically, or substantially identically. The radar system 3a-1 includes a transmitting/receiving device 9a and a high-frequency local oscillator 7a. The high-frequency local oscillator 7a has a high-frequency source 8 that generates a high-frequency local oscillator signal using a local reference signal. The high-frequency source 8 may be a high-frequency source of a fixed frequency, or a temporarily fixed frequency (for example, in the case of a stepped signal), for example, 20 GHz. The high-frequency local oscillator 7a outputs a high-frequency local oscillator signal to the transmitting/receiving device 9a. Optionally, the radar system 3a-1 may be intended to have a number of transmitting/receiving devices 9a, and the high-frequency local oscillator 7a provides the high-frequenc