Driver assistance device for a vehicle and method for operating a radar device

摘要

The invention relates to a driver assistance device (2) for a vehicle (1), which driver assistance device has a radar appliance (3, 4) for determining at least one measured variable (α1, α2, R1, R2) referenced to an object (10) that is external to the vehicle, wherein the radar appliance (3, 4) comprises:
at least a first and a second reception antenna (14, 15), each for receiving signals (SE1, SE2),a first down-converter (17), which is coupled to the first reception antenna (14) via a first reception path (16), and a second down-converter (23), which is coupled to the second reception antenna (15) via a second reception path (21), each for down-converting the received signals (SE1, SE2) into respective baseband signals (SB1, SB2), anda control device (5) for receiving the baseband signals (SB1, SB2) and for determining the at least one measured variable (α1, α2, R1, R2) using the baseband signals (SB1, SB2),

wherein the radar appliance (3, 4) has test means (32) for producing a local check signal (SP) and for coupling same check signal (SP) into the first reception path (16) and/or into the second reception path (21), as a result of which the control device (5) receives firstly the check signal (SP) that has been down-converted by the first down-converter (17) as a first test signal (ST1) and/or secondly the check signal (SP) that has been down-converted by the second down-converter (23) as a second test signal (ST2). The invention also relates to an appropriate method.

主权项

1. A driver assistance device for a vehicle, the driver assistance device having a radar appliance for determining at least one measured variable (α1, α2, R1, R2) referenced to an object that is external to the vehicle, the radar appliance comprising:
at least a first and a second reception antenna, each for receiving signals (SE1, SE2); a first down-converter, which is coupled to the first reception antenna via a first reception path, and a second down-converter, which is coupled to the second reception antenna via a second reception path, each for down-converting the received signals (SE1, SE2) into respective baseband signals (SB1, SB2); a control device for receiving the baseband signals (SB1, SB2) and for determining the at least one measured variable (α1, α2, R1, R2) using the baseband signals (SB1, SB2); test means for producing a local single-sideband-modulated check signal (SP) and for coupling the check signal (SP) into the first reception path and into the second reception path, as a result of which the control device receives firstly the check signal (SP) that has been down-converted by the first down-converter as a first test signal (ST1) and/or secondly the check signal (SP) that has been down-converted by the second down-converter as a second test signal (ST2) wherein said test means comprises;
an up-converter for producing the local check signal (SP), the output of said up-converter being coupled firstly to the first reception path and secondly to the second reception path;a local oscillator for providing an oscillator signal, said local oscillator being shared by the first and second down-converters and by the up-converter; andwherein the local oscillator is coupled to an input of the up-converter via a directional coupler or a power splitter, wherein the directional coupler or the power splitter is designed to tap off a portion of between −25 dB and −15 dB from a power of the oscillator signal for the up-converter.