Abstract: An electronic scan type radar device which uses a high resolution performance processing to estimate directions of arrival of radio waves, wherein powers of arrival waves received for targets are accurately calculated, that is, a vehicle-mounted radar device utilizing electronic scan which uses a predetermined angle estimation system to estimate directions of arrival of reflected waves, comprising finding mode vectors for angles calculated from the receive signals of the antennas, decomposing a vector of the receive signals into directions of the mode vectors, and defining the lengths of the decomposed vectors the receive powers of the reflected waves arriving from the targets. Due to this method, even if there are targets, it is possible to accurately calculate the powers of the arrival waves, whereby pairing is accurately performed, the precision of detection of targets is improved, and erroneous operation of a vehicle-mounted radar device utilizing electronic scans is prevented.

Abstract: The conventional ESPRIT method is accompanied by the problem of very long signal processing time. The radar device of the invention includes a signal vector-forming unit for forming signal vectors based on waves reflected from an object and received by using a plurality of receiving antennas; a submatrix-forming unit for forming submatrices based on the signal vectors; a regular matrix operation unit for calculating a regular matrix from the submatrices; an eigenvalue decomposition unit for calculating an eigenvalue of the regular matrix; and an angle calculation unit for calculating an angle at where the object is present from the eigenvalue.

Abstract: In an in-vehicle radar device, as a vertical azimuth which is an azimuth of a target in a direction perpendicular to a ground surface, a real image vertical azimuth which is an azimuth of a real image existing above ground is calculated from a reflected wave generated when a transmission signal transmitted from a transmission antenna reflected from the target, and a virtual image vertical azimuth which is an azimuth of a virtual image existing underground is calculated from a reflected wave generated when the transmission signal transmitted from the transmission antenna is reflected from the target and reflected again from the ground surface. Next, in the in-vehicle radar device, an angle difference between the real image vertical azimuth and the virtual image vertical azimuth which are calculated is calculated, and a height of the target from the ground surface is calculated using the calculated angle difference.

Abstract: A radar apparatus includes a retrieval unit, an estimation unit, a calculation unit, and a determination unit. The retrieval unit retrieves a strong reflection object based on a signal strength which a frequency spectrum of a beat signal generated by mixing a transmission signal which is frequency-modulated and emitted and a reception signal which is formed in the transmission signal is reflected on a target indicates. The estimation unit estimates an estimation orientation which is an orientation of a target assumed to be present around the strong reflection object, based on a relative distance to the strong reflection object. The calculation unit calculates power which is the signal strength for the estimation orientation by generating an orientation spectrum in the estimation orientation based on a frequency component corresponding to the relative distance. The determination unit determines whether there is the target in the estimation orientation based on the power.

Abstract: There is provided a calculation device for a radar apparatus which is configured to specify a direction of a target based on respective reception signals of a plurality of antennae. A calculation unit is configured to use a predetermined estimation algorithm of estimating angles of targets corresponding to a preset separable-number from the respective reception signals, set an arbitrary separable-number to generate a mode vector from the estimated angles of the targets, obtained by the predetermined estimation algorithm, and determine whether the set separable-number is proper or not based on a magnitude of an orthogonal component calculated from the mode vector and an input vector of the respective reception signals.

Abstract: In a radar device including: a transmission antenna group having a plurality of transmission antennas; a reception antenna group having a plurality of reception antennas; and transmission switchover means to transmit transmission waves in a way that sequentially switches over the transmission antennas of the transmission antenna group, the reception antenna group receiving reflected waves, reflected from a target, of transmission waves of the transmission antennas when sequentially transmitting the transmission waves, is made to function as a virtual sub-array corresponding to the transmission antennas. The target is thus detected by executing a space averaging process based on a relative position, to the reception antenna group, of each of the transmission antennas undergoing the transmission switchover with respect to the virtual correlation values corresponding to the plurality of virtual sub-arrays.

Abstract: There is provided a radar apparatus of an electronic scan type configured to transmit an electric wave and calculate an angle of a target based on a phase difference of respective reception signals, thereby detecting a target position. An antenna unit transmits and receives the electric wave and provided with two transmission antennae. A transmission unit alternately transmits an electric wave having a first beam pattern and an electric wave having a second beam pattern from the two transmission antennae. First and second reception units calculate arrival angles and reception levels of reflected waves calculated from respective reception signals which are obtained by receiving the reflected waves by the first and second beam patterns. A comparison unit compares the reception levels by combining the arrival angles of the reflected waves. A determination unit determines whether a target actually exists at the arrival angles in accordance a comparison result.

Abstract: An electronic scan type radar device which uses a high resolution performance processing to estimate directions of arrival of radio waves, wherein powers of arrival waves received for targets are accurately calculated, that is, a vehicle-mounted radar device utilizing electronic scan which uses a predetermined angle estimation system to estimate directions of arrival of reflected waves, comprising finding mode vectors for angles calculated from the receive signals of the antennas, decomposing a vector of the receive signals into directions of the mode vectors, and defining the lengths of the decomposed vectors the receive powers of the reflected waves arriving from the targets. Due to this method, even if there are targets, it is possible to accurately calculate the powers of the arrival waves, whereby pairing is accurately performed, the precision of detection of targets is improved, and erroneous operation of a vehicle-mounted radar device utilizing electronic scans is prevented.

Abstract: The conventional ESPRIT method is accompanied by the problem of very long signal processing time. The radar device of the invention includes a signal vector-forming unit for forming signal vectors based on waves reflected from an object and received by using a plurality of receiving antennas; a submatrix-forming unit for forming submatrices based on the signal vectors; a regular matrix operation unit for calculating a regular matrix from the submatrices; an eigenvalue decomposition unit for calculating an eigenvalue of the regular matrix; and an angle calculation unit for calculating an angle at where the object is present from the eigenvalue.

Abstract: In a radar device including: a transmission antenna group having a plurality of transmission antennas; a reception antenna group having a plurality of reception antennas; and transmission switchover means to transmit transmission waves in a way that sequentially switches over the transmission antennas of the transmission antenna group, the reception antenna group receiving reflected waves, reflected from a target, of transmission waves of the transmission antennas when sequentially transmitting the transmission waves, is made to function as a virtual sub-array corresponding to the transmission antennas. The target is thus detected by executing a space averaging process based on a relative position, to the reception antenna group, of each of the transmission antennas undergoing the transmission switchover with respect to the virtual correlation values corresponding to the plurality of virtual sub-arrays.