Abstract:
The invention relates to a method for recognising a change in lane of a vehicle (20). Said device comprises an angular resolution locating device (10) for locating vehicles (VEH1, VEH2, VEH3) travelling in front and a device (44) for determining the individual yaw rate (φ0). The invention is characterised in that the angular speed (φI) of at least one vehicle travelling in front of the first vehicle is measured in relation to the said individual vehicle (20) with the aid of the locating device (10) and a lane change signal (LC) indicating the lane change is formed by comparing the measured angular speed (φi) with the individual yaw rate (φ0).
Abstract:
A radar detection process includes computing a derivative of an FFT output signal to detect an object within a specified detection zone. In one embodiment, a zero crossing in the second derivative of the FIT output signal indicates the presence of an object. The range of the object is determined as a function of the frequency at which the zero crossing occurs. Also described is a detection table containing indicators of the presence or absence of an object within a respective radar beam and processing cycle. At least two such indicators are combined in order to detect the presence of an object within the detection zone and with changing range gates in each of the antenna beams the coverage of the detection zone can be varied.
Abstract:
A radar detection process includes computing a derivative of an FFT output signal to detect an object within a specified detection zone. In one embodiment, a zero crossing in the second derivative of the FFT output signal indicates the presence of an object. The range of the object is determined as a function of the frequency at which the zero crossing occurs. Also described is a detection table containing indicators of the presence or absence of an object within a respective radar beam and processing cycle. At least two such indicators are combined in order to detect the presence of an object within the detection zone and with changing range gates in each of the antenna beams the coverage of the detection zone can be varied.
Abstract:
A radar detection process includes computing a derivative of an FFT output signal to detect an object within a specified detection zone. In one embodiment, a zero crossing in the second derivative of the FFT output signal indicates the presence of an object. The range of the object is determined as a function of the frequency at which the zero crossing occurs. Also described is a detection table containing indicators of the presence or absence of an object within a respective radar beam and processing cycle. At least two such indicators are combined in order to detect the presence of an object within the detection zone and with changing range gates in each of the antenna beams the coverage of the detection zone can be varied.
Abstract:
A radar transmitter includes a digital ramp generator circuit for generating a VCO control signal. The ramp generator includes a digital signal processor and a digital-to-analog converter. In one embodiment, the VCO output signal is up-converted to provide the transmit signal and in another embodiment, the VCO operates over the transmit frequency. Also described is a VCO comprising a DR and a phase shifter. A temperature compensation feature includes detecting the transmit frequency and comparing the DSP output generating the detected frequency to a DSP output stored in association with the detected frequency. Also described is a technique for compensating for non-linear VCO operation in which the DSP output words are adjusted to provide a waveform complementary in shape to the non-linear VCO characteristic. Susceptibility of the radar to interference is reduced by randomly varying at least one parameter of the ramp signal, such as offset interval or voltage range, in at least one ramp signal cycle.
Abstract:
When a vehicle travels along a curve of a road, a target vehicle acceleration/deceleration (dV s0 /dt) that is used for accelerating/decelerating the vehicle to a target vehicle speed (V s0_t ), which is set for the curve, is calculated. Based on a comparison between a present vehicle speed (V s0 ) of the vehicle and the target vehicle speed (V s0_t ) the vehicle is controlled such that an acceleration/deceleration of the vehicle coincides with the target vehicle acceleratio/deceleration (dV s0 /dt).
Abstract:
A video amplifier for a radar receiver includes a temperature compensating attenuator. The attenuator includes a temperature sensitive device, such as a thermistor, arranged in a voltage divider network and is coupled in cascade between two filter stages. Each of the filter stages has a bandpass characteristic in order to filter low-frequency leakage signals and provide sensitivity control based on frequency and thus range, while also filtering high frequency signals to reduce aliasing.