Radar system, and transmission method

Abstract

To provide a radar system capable of efficiently detecting targets.SOLUTION: The radar system includes: a first radar circuit that transmits a first transmission signal; and a second radar circuit that transmits a second transmission signal. Multiple transmission cycles for transmitting the first transmission signal and the second transmission signal include: a first transmission cycle in which the transmission timing of the first transmission signal is delayed by a specified value than the transmission timing of the second transmission signal; and a second transmission cycle in which the transmission timing of the second transmission signal is delayed by a specified value than the transmission timing first transmission signal.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a radar device and a transmission method.

Background Art

[0002] In recent years, studies on radar devices using radar transmission signals (hereinafter also referred to as TxSig) with short wavelengths including microwaves or millimeter waves that can obtain high resolution have been underway. As a radar device, for example, in addition to a receiving unit, a transmitting unit is also provided with a plurality of antennas (array antennas), and a configuration (sometimes called MIMO (Multiple Input Multiple Output) radar) that performs beam scanning by signal processing using the transmit-receive array antennas has been proposed (see, for example, Non-Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Non-Patent Documents

[0004]

Non-Patent Document 1

Non-Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, a method for detecting a target (or object) in a radar device (e.g., MIMO radar) has not been fully studied.

[0006] Non-limiting embodiments of the present disclosure contribute to providing a radar device and a transmission method capable of efficiently detecting a target.

Means for Solving the Problems

[0007] A radar device according to an embodiment of the present disclosure includes a first radar circuit that transmits a first transmission signal and a second radar circuit that transmits a second transmission signal. In a plurality of transmission periods in which the first transmission signal and the second transmission signal are transmitted, a first transmission period in which the transmission timing of the first transmission signal is delayed by a specified value from the transmission timing of the second transmission signal and a second transmission period in which the transmission timing of the second transmission signal is delayed by the specified value from the transmission timing of the first transmission signal are included.

[0008] These general or specific embodiments may be implemented in a system, device, method, integrated circuit, computer program, or recording medium, or may be implemented in any combination of a system, device, method, integrated circuit, computer program, and recording medium.

Advantages of the Invention

[0009] According to an embodiment of the present disclosure, a radar device can efficiently detect a target.

[0010] Further advantages and effects in an embodiment of the present disclosure will be clarified from the specification and the drawings. Such advantages and / or effects are respectively provided by several embodiments and the features described in the specification and the drawings, but not all of them are necessarily provided in order to obtain one or more identical features.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

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Figure 10

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Figure 12

Figure 13

Modes for Carrying Out the Invention

[0012] MIMO radars can be broadly classified into, for example, a "monostatic configuration" and a bistatic configuration or a multistatic configuration (hereinafter referred to as "bi / multistatic configuration"). Hereinafter, the monostatic configuration will be described as the "MNS configuration", and the bi / multistatic configuration will be described as the "BMS configuration".

[0013] In the MNS configuration, for example, a configuration may be adopted in which a transmitting unit (including, for example, a plurality of transmitting antennas and a high-frequency wireless unit) and a receiving unit (including, for example, a plurality of receiving antennas and a high-frequency wireless unit) are included in the same housing.

[0014] Also, in the BMS configuration, for example, a configuration may be adopted in which the transmitting unit and the receiving unit are included in different housings. For example, in the BMS configuration, each housing is installed at a separated distance, and the transmitting unit and the receiving unit are connected to a control unit that performs synchronization control. The bistatic configuration is, for example, a pair of a transmitting unit and a receiving unit, and the transmitting unit and the receiving unit are configured at separated distances. The multistatic configuration is, for example, a configuration in which at least one or both of the transmitting unit and the receiving unit are plural. The multistatic configuration is disclosed in, for example, Non-Patent Document 2.

[0015] Hereinafter, in the non-limiting embodiments of the present disclosure, attention will be paid to the BMS configuration. For example, in the non-limiting embodiments of the present disclosure, a BMS configuration using a plurality of MIMO radars with the MNS configuration will be described. The BMS configuration using a plurality of MIMO radars with the MNS configuration may also be referred to as, for example, a "mono&multistatic configuration".

[0016] An example of a radar apparatus with a mono&multistatic configuration when using radar #1 and radar #2, which are MIMO radars with the MNS configuration, is shown in FIG. 1.

[0017] Radar #1 is, for example, a "MIMO radar with a first MNS configuration" that outputs a radar transmission wave (also called TxSig) from a radar transmission antenna group Tx#1 and receives a reflected wave signal from target #1 by a radar reception antenna group Rx#1 within the same housing (for example, path (1)).

[0018] Similarly, radar #2 is, for example, a "MIMO radar with a second MNS configuration" that outputs a radar transmission wave from a radar transmission antenna group Tx#2 and receives a reflected wave signal from target #3 by a radar reception antenna group Rx#2 within the same housing (for example, path (2)).

[0019] Also, the radar device shown in FIG. 1 may perform an operation of transmitting a radar transmission wave from the transmission antenna group Tx#1 of radar #1 and receiving the reflected wave signal from target #2 by the reception antenna group Rx#2 of radar #2. The radar device performing this operation may be regarded as, for example, a "MIMO radar with a first BMS configuration" (for example, path (3)).

[0020] Similarly, an operation of transmitting a radar transmission wave from the transmission antenna group Tx#2 of radar #2 and receiving the reflected wave signal from target #2 by the reception antenna group Rx#1 of radar #1 may be performed. The radar device performing this operation may be regarded as, for example, a "MIMO radar with a second BMS configuration" (for example, path (4)).

[0021] In addition to the radar with the MNS configuration, for use as a radar with the BMS configuration, for example, a synchronization unit that performs synchronization control between a plurality of radars with the MNS configuration installed at distant positions may be used. For example, in FIG. 1, when a frequency-modulated FMCW (Frequency Modulated Continuous Wave) signal (for example, a "chirp signal") is used as the radar transmission wave, the synchronization unit may generate a chirp signal and supply the chirp signal commonly to radar #1 and radar #2. Thereby, it can be used as a MIMO radar with a first MNS configuration and a MIMO radar with a second MNS configuration, and it is also possible to be used as a MIMO radar with a first BMS configuration and a MIMO radar with a second BMS configuration.

[0022] However, when the synchronization unit supplies the chirp signal commonly to Radar #1 and Radar #2, when supplying a chirp signal that becomes a high-frequency signal in the radio frequency band (for example, 60 to 80 GHz band), it is desirable to use high-quality wiring for high frequencies with little attenuation and transmission distortion of the high-frequency signal, and the cost of the entire radar system can increase. Therefore, for example, a configuration may be adopted in which chirp signals are individually generated in Radar #1 and Radar #2, and a synchronization unit that outputs a synchronization signal for controlling the output timing (or transmission timing) of the chirp signal may be used.

[0023] In this case, the synchronization signal has a frequency band on the order of MHz, for example, and it is not necessary to use high-quality wiring for high-frequency signals in the radio frequency band, so the cost of the entire radar system can be reduced. In this case, when using an MIMO radar with an MNS configuration, transmission timing errors, frequency errors, or phase errors may be included between the chirp signals individually generated in Radar #1 and Radar #2. Therefore, a radar configuration that suppresses the deterioration of radar detection performance caused by these errors is expected.

[0024] For example, for the transmission of a radar with a BMS configuration using radars with the first and second MNS configurations, there may be an application of multiplex transmission that applies time division (TDM: Time Division Multiplexing), frequency division (FDM: Frequency Division Multiplexing), or code division (CDM: Code Division Multiplexing).

[0025] Regarding the transmission of a radar with a BMS configuration, for example, the application of time division and frequency division transmission is disclosed in Patent Document 1 or Patent Document 2, respectively, and the following cases are assumed.

[0026] In time-division transmission in the BMS configuration, for example, after transmission from Radar #1 to Radar #2 in the BMS configuration ends, switching to transmission from Radar #2 to Radar #1 in the BMS configuration causes the time taken for transmission processing in both the MNS configuration and the BMS configuration to increase easily, and the tracking performance when the target moves deteriorates easily.

[0027] For example, in FIG. 1, as the radar transmission wave, when using a frequency-modulated FMCW (Frequency Modulated Continuous Wave) signal (e.g., "chirp signal") and performing time-division transmission between Radar #1 and Radar #2 every transmission period (Tr) of the chirp signal, the following operations occur.

[0028] In the first Tr, Radar #1 transmits the chirp signal (chirp#1) generated at Radar #1 from the transmission antenna, and for example, as shown by the path (1) in FIG. 1, receives the signal (target reflected wave #1) reflected by Target #1 at the receiving antenna of Radar #1. In the receiving operation, Radar #1 mixes the received signal of the target reflected wave #1 with the chirp signal generated at Radar #1 to output a beat signal corresponding to the propagation time TP(1) MNS#1 of path (1), and by analyzing the frequency of the beat signal, detects the target distance R(1) MNS#1 in the MNS configuration at Radar #1.

[0029] During the receiving operation of Radar #1, Radar #2 stops the transmission operation of the chirp signal (or sets the transmission power from the transmission antenna to almost zero), and for example, as shown by the path (3) in FIG. 1, receives the signal (target reflected wave #2) reflected by Target #2 from the chirp signal (chirp#1) transmitted from Radar #1 at the receiving antenna of Radar #2. In the receiving operation, Radar #2 mixes the received signal of the target reflected wave #2 with the chirp signal generated at Radar #2 to output a beat signal corresponding to the propagation time TP(3) BMS#2 of path (3), and by analyzing the frequency of the beat signal, detects the target distance R(3) in the BMS configuration from Radar #1 to Radar #2BMS#2 Detect it.

[0030] In the second Tr, radar #1 and radar #2 perform an operation in which the operations of radar #1 and radar #2 in the first Tr are swapped. For example, radar #2 transmits the chirp signal (chirp #2) generated by radar #2 from the transmitting antenna and performs a receiving operation. As a result, for example, as shown in path (2) of FIG. 1, the propagation time TP(2) of the signal (target reflected wave #3) reflected by target #3 MNS#2 The target distance R(2) in the MNS configuration corresponding to MNS#2 is detected. During the receiving operation of this radar #2, radar #1 stops the transmission operation of the chirp signal and performs a receiving operation. For example, as shown in path (4) of FIG. 1, the propagation time TP(4) of the target reflected wave #2 BMS#1 The target distance R(4) in the BMS configuration from radar #2 to radar #1 corresponding to BMS#1 is detected.

[0031] Thereafter, radar #1 and radar #2 perform the same operation as the first Tr in the subsequent odd-numbered Trs and the same operation as the second Tr in the subsequent even-numbered Trs, thereby performing Doppler frequency analysis of the target at a 2Tr period at each target distance detected by each radar and performing Doppler detection of the target.

[0032] Since the radar device shown in FIG. 1 performs Doppler frequency analysis of the reflected wave signal every two chirp signal transmission periods (2Tr), the maximum detectable Doppler is likely to be reduced, and the Doppler frequency range is reduced to ±1 / (4Tr). In the following, the Doppler frequency is also denoted as "DFreq". Also, since the radar device shown in FIG. 1 transmits the radar transmission signal in a time-division manner every two chirp signal transmission periods (2Tr), the number of transmissions of the radar transmission signal from radar #1 or #2 per required time is reduced, so there is a possibility that the target detection performance deteriorates (or the measurement time becomes longer if the detection performance is to be maintained).

[0033] Also, when the chirp signal chirp#1 of radar #1 and the chirp signal chirp#2 of radar #2 are individually generated by their respective radars, the transmission timing of the chirp signal, the deviation (offset) of the transmission frequency, or the phase error may be included.

[0034] In this case, due to the transmission timing or the offset of the transmission frequency, for example, the target distances R(4) BMS#1 and R(3) BMS#2 will be offset and detected, and a detection distance error may occur. Note that if such an offset of the transmission timing or the transmission frequency is fixed and its variation amount can be ignored, the error can be corrected by measuring the offset amount before radar ranging.

[0035] On the other hand, if the offset of the transmission timing or the transmission frequency changes with temperature or over time and it is difficult to ignore its variation, a detection distance error may occur due to the variation of the offset of the transmission timing or the transmission frequency. In this case, it is expected that the radar device has a configuration for detecting the offset amount while performing radar ranging and correcting the detection distance error.

[0036] Also, when the variation of the phase error is large when the chirp signal chirp#1 of radar #1 and the chirp signal chirp#2 of radar #2 are individually generated by their respective radars, the Doppler detection error in the radar device tends to increase, and the Doppler detection performance may deteriorate.

[0037] Also, for example, when performing frequency-division multiplexed transmission in a BMS configuration (e.g., a chirp signal is transmitted at a frequency difference outside the mutual reception bands of Radar #1 and Radar #2), it is difficult to receive in the first and second BMS configurations when all the receiving antennas of Radar #1 or Radar #2 perform the reception process of the transmitting antenna of that radar. On the other hand, for example, when performing reception processing for a transmission signal having a frequency different from the transmission signal of that radar in a part of the receiving antennas of Radar #1 or Radar #2, the number of receiving antennas that receive the reflected wave signal from the transmission signal of that radar decreases. For this reason, in the radar device shown in FIG. 1, a decrease in the received signal level or a deterioration in the angle measurement accuracy is likely to occur.

[0038] In a non-limiting embodiment of the present disclosure, a method for improving the efficiency of target detection in a mono & multi-static configuration will be described. For example, in a non-limiting embodiment of the present disclosure, a multiplexed transmission method will be described that maintains the radar detection performance (e.g., detectable DFreq range) in an MNS configuration, enables simultaneous multiplexed transmission in a BMS configuration in addition to the MNS configuration, and reduces the time required for radar ranging.

[0039] For example, in a non-limiting embodiment of the present disclosure, in addition to the radar positioning in the MNS configuration of Radar #1 and Radar #2 shown in FIG. 1, radar positioning in the BMS configuration from Radar #1 to Radar #2 and radar positioning in the BMS configuration from Radar #2 to Radar #1 may be performed simultaneously.

[0040] Also, for example, all the receiving antennas of Radar #1 or Radar #2 may perform reception processing for the transmission signal of that radar.

[0041] Note that the radar device according to an embodiment of the present disclosure may be mounted on a moving body such as a vehicle, for example. For example, the radar device may be mounted near at least one corner in front of and behind the vehicle, or may be mounted near the center or from the center to near the corner of at least one of the front and rear of the vehicle.

[0042] The positioning output (information regarding the estimation result) of the radar device mounted on the moving body is output to a control ECU (Electronic Control Unit) (not shown), such as an advanced driver assistance system (ADAS: Advanced Driver Assistance System) that enhances collision safety, or an autonomous driving system, and may be used for vehicle drive control or alarm call control.

[0043] In addition, the radar device according to an embodiment of the present disclosure may be attached to a relatively high structure (not shown), such as a roadside utility pole or traffic signal. Such a radar device can be used as a sensor in, for example, a support system that enhances the safety of passing vehicles or pedestrians, or a system for preventing the intrusion of suspicious persons. Also, the positioning output of the radar device may be output to a control device (not shown) in, for example, a support system that enhances safety or a suspicious person intrusion prevention system, and may be used for alarm call control or anomaly detection control.

[0044] Note that the use of the radar device is not limited to these, and it may be used for other purposes.

[0045] Also, a target is an object detected by the radar device, and includes, for example, vehicles (including four-wheeled and two-wheeled vehicles), people, blocks, or curbs.

[0046] Hereinafter, an embodiment according to an embodiment of the present disclosure will be described in detail with reference to the drawings. In the embodiment, the same reference numerals are assigned to the same components, and the description thereof will be omitted because it is redundant.

[0047] Hereinafter, in the radar device, in the transmission branch, different transmission signals multiplexed simultaneously from a plurality of transmission antennas are transmitted, and in the reception branch, a configuration in which each transmission signal is separated and reception processing is performed (for example, a MIMO radar configuration) will be described.

[0048] Note that the radar device is not limited to the MIMO radar configuration. For example, it may be a SIMO (Single Input Multiple Output) radar configuration that sends a transmission signal from one transmitting antenna. Even in the case of the SIMO radar configuration, the same effects as those of the MIMO radar configuration described later can be obtained. In the case of the SIMO radar configuration, in the following description, it is the case where the number of transmitting antennas (or transmission multiplexing) is 1, and parts related to transmission multiplexing in the radar transmission unit (for example, the Doppler shift unit described later), and parts related to separation of the transmission multiplexed signal in the radar reception unit (for example, the separation unit described later) can be omitted.

[0049] Also, in the following, as an example, the configuration of a radar system (also called fast chirp modulation, for example) using a frequency-modulated pulse wave such as a chirp pulse will be described. However, the modulation method is not limited to frequency modulation. For example, one embodiment of the present disclosure is also applicable to a radar system using a pulse compression radar that transmits a pulse train by phase modulation or amplitude modulation.

[0050] (Embodiment) [Configuration of Radar Device] The radar device (or a radar system) according to the present embodiment may have, for example, a plurality of radar units (corresponding to radar circuits. For example, MIMO radar). Further, the radar device according to the present embodiment may have, for example, a synchronization unit that performs synchronization control between the plurality of radar units, and an integration unit that integrates the positioning outputs of the plurality of radar units.

[0051] For example, the radar device 1 shown in FIG. 2 is a radar system including a first radar unit 10 (or represented as radar unit 10-1) having a plurality of transmitting and receiving antennas (not shown), and a second radar unit 10 (or represented as radar unit 10-2) having a plurality of transmitting and receiving antennas (not shown).

[0052] In the radar device 1 shown in FIG. 2, the synchronization unit 20 performs synchronization control between the first radar unit 10 and the second radar unit 10. For example, the synchronization unit 20 may output a reference clock signal (or also referred to as a reference signal) as a synchronization control signal to the first radar unit 10 and the second radar unit 10 for synchronization control.

[0053] Here, the reference signal is, for example, a high-frequency signal of about several tens to several hundreds of MHz. When the synchronization unit 20 uses the reference signal as the synchronization control signal, the system cost can be reduced compared to the case of using a chirp signal (for example, on the order of GHz). Also, the reference signal of the synchronization unit 20 may be used, for example, as the reference signal of a VCO (Voltage Controlled Oscillator) that generates a chirp signal. Thus, when the synchronization unit 20 uses the reference signal, since the chirp signal is individually generated in each of the first radar unit 10 and the second radar unit 10, the phase consistency between the first radar unit 10 and the second radar unit 10 is not guaranteed, and a phase shift or frequency shift (including a shift in transmission timing) of a degree that drifts and displaces is likely to occur. The radar device 1 may have, for example, in the integration unit 30, a distance correction unit that corrects the detected distance (or the distance detection error) in order to correct the distance detection error caused by the phase shift or frequency shift between the first radar unit 10 and the second radar unit 10.

[0054] For example, the radar device 1 may transmit a transmission signal from a plurality of transmission antennas of the transmission unit 100-1 of the first radar unit 10. The radar device 1 may receive, for example, a reflected wave signal obtained by reflecting the transmission signal of the first radar unit 10 at the target #1 (corresponding to the target #1 in FIG. 1) in the receiving unit 200-1 having a plurality of receiving antennas of the first radar unit 10, and perform positioning processing of the target #1 (for example, radar positioning by the MNS configuration).

[0055] Furthermore, the radar device 1 may receive, for example, a reflected wave signal obtained by reflecting the transmission signal of the first radar unit 10 from a target #2 (corresponding to the target #2 in FIG. 1) by the receiving unit 200-2 having a plurality of receiving antennas of the second radar unit 10, and perform positioning processing of the target #2 (for example, radar positioning by a BMS configuration).

[0056] Similarly, for example, the radar device 1 may transmit transmission signals from a plurality of transmission antennas of the radar transmitter 100-2 of the second radar unit 10. The radar device 1 may receive, for example, a reflected wave signal obtained by reflecting the transmission signal of the second radar unit 10 from a target #3 (corresponding to the target #3 in FIG. 1) by the receiving unit 200-2 having a plurality of receiving antennas of the second radar unit 10, and perform positioning processing of the target #3 (for example, radar positioning by an MNS configuration).

[0057] Furthermore, the radar device 1 may receive, for example, a reflected wave signal obtained by reflecting the transmission signal of the second radar unit 10 from a target #2 (corresponding to the target #2 in FIG. 1) by the receiving unit 200-1 having a plurality of receiving antennas of the first radar unit 10, and perform positioning processing of the target #2 (for example, radar positioning by a BMS configuration).

[0058] Note that the reception processing in the first radar unit 10 and the second radar unit 10 may be performed using, for example, MIMO virtual antennas.

[0059] Also, in the present embodiment, the radar device 1 may perform multiplex transmission (or simultaneous transmission) of the transmission signal transmitted from the first radar unit 10 and the transmission signal transmitted from the second radar unit 10.

[0060] For example, each of the first radar unit 10 and the second radar unit 10 may have a separation unit that separates, from the received signal, a reflected wave signal corresponding to the transmission signal from the transmitter 100 of the radar unit and a reflected wave signal corresponding to the transmission signal from the transmitter 100 of the other radar unit.

[0061] Further, for example, each of the first radar unit 10 and the second radar unit 10 may include a first angle measurement unit that performs angle measurement using the reflected wave signal of the transmission signal from the transmission unit 100 of the radar unit separated in the separation unit, and a second angle measurement unit that performs angle measurement using the reflected wave signal of the transmission signal from the transmission unit 100 of the other radar unit separated in the separation unit.

[0062] Also, in FIG. 2, the integration unit 30 may, for example, integrate the positioning outputs from the first radar unit 10 (for example, the first and second positioning outputs) and the positioning outputs from the second radar unit 10 (for example, the first and second positioning outputs) to perform positioning of the target. Note that the positioning is information including direction, distance, and Doppler frequency, and may further include separation index information of the Doppler multiplex signal (details will be described later).

[0063] Further, the integration unit 30 may, for example, have a distance correction unit that corrects when detecting the distance of the reflected wave signal corresponding to the transmission signal from the transmission unit 100 of the other radar unit using the output from the separation unit that separates the reflected wave signal corresponding to the transmission signal from the transmission unit 100 of the other radar unit in the first radar unit 10 and the second radar unit 10 (for example, the second positioning output of each radar unit 10). By the correction by the distance correction unit, even when a transmission timing error or a frequency error of the transmission signal is included between the first radar unit 10 and the second radar unit 10, the radar device 1 can perform distance correction of the reflected wave signal corresponding to the transmission signal from the transmission unit 100 of the other radar unit using the output of the distance correction unit, and can improve the distance detection accuracy.

[0064] With such a configuration, the radar device 1 receives the reflected wave signal in the receiving unit 200-1 and the receiving unit 200-2, separates the received signal according to whether it is a reflected wave signal caused by the transmission signal from its own radar unit or a reflected wave signal caused by the transmission signal from another radar unit, and can appropriately perform positioning processing based on the position information of the first radar unit 10 and the second radar unit 10. Also, since the radar device 1 can transmit the transmission signal from the first radar unit 10 and the second radar unit 10 at the same timing, it is possible to shorten the positioning time compared to the case of time-division multiplex transmission.

[0065] For example, in FIG. 2, the first radar unit 10 and the second radar unit 10 may be installed at locations separated from each other. In this case, the radar device 1 can be used as a so-called BMS configuration. For example, radar positioning in a BMS configuration in which the first transmission signal from the first radar unit 10 is received by the receiving unit 200-2 of the second radar unit 10, and radar positioning in a BMS configuration in which the second transmission signal from the second radar unit 10 is received by the receiving unit 200-1 of the first radar unit 10 can be performed simultaneously, and the positioning time can be shortened compared to the case of time-division multiplexed transmission.

[0066] Note that since the first radar unit 10 and the second radar unit 10 shown in FIG. 2 include the same configuration, hereinafter, they will be collectively referred to and described as the "radar unit 10", and the different operations of the first radar unit 10 and the second radar unit 10 will be separately described.

[0067] A configuration example of the radar device 1 using a frequency-modulated chirp signal as a radar transmission wave is shown in FIG. 3. Note that the radar device 1 shown in FIG. 3 will be described with respect to a MIMO radar configuration in which different transmission signals multiplexed by Doppler are sent from a plurality of transmission antennas, and in the receiving branch, each transmission signal is separated and received processing is performed, but the present invention is not limited to this, and the same effect can be obtained by using code multiplexed transmission from a plurality of transmission antennas.

[0068] The radar device 1 in FIG. 3 shows an example of the first radar unit 10-1, the synchronization unit 20, and the integration unit 30 in FIG. 2. For example, the first radar unit 10-1 corresponds to the radar unit 10. Note that in FIG. 3, a configuration example corresponding to radars other than the first radar unit 10-1 and the second radar unit 10-2 in FIG. 2 is shown, and the notations of other radar units 10 are omitted.

[0069] In FIG. 3, the synchronization unit 20 generates, for example, a synchronization signal and supplies it to a plurality of radar units 10.

[0070] The integration unit 30 integrates, for example, the positioning outputs from a plurality of radar units 10 to perform the positioning of a target. Further, the integration unit 30 (for example, the distance correction unit 301 described later) performs correction when detecting the distance of a reflected wave signal corresponding to a transmission signal from another radar unit using the second positioning output (for example, the output of the angle measurement unit 213-2 described later) of each of the plurality of radar units 10.

[0071] The radar unit 10 includes, for example, a transmission unit (corresponding to a transmission branch or a radar transmission circuit) 100 and a reception unit (corresponding to a reception branch or a radar reception circuit) 200.

[0072] The transmission unit 100 generates, for example, a TxSig (for example, a chirp signal) based on the synchronization signal generated by the synchronization unit 20, and transmits the generated TxSig at a predetermined transmission period using a transmission array antenna composed of a plurality of transmission antennas 102-1 to 102-Nt.

[0073] The reception unit 200 receives, for example, a reflected wave signal that is the TxSig reflected by a target (target, corresponding to the targets #1 to #3 in FIG. 1) using a reception array antenna including a plurality of reception antennas 202-1 to 202-Na. The reception unit 200 processes the reflected wave signal received by each reception antenna 202 to detect, for example, the presence or absence of a target or perform positioning.

[0074] [Configuration example of transmission unit 100] In FIG. 3, the transmission unit 100 of the radar unit 10 includes, for example, Doppler shift units 101-1 to 101-Nt, transmission antennas 102-1 to 102-Nt (for example, Tx#1 to Tx#Nt), and a generation unit 103. Hereinafter, the Doppler shift unit will also be referred to as the "DS unit". Each transmission antenna 102 may be connected to an individual DS unit 101. Also, the radar unit 10 in FIG. 3 corresponds to the first radar unit 10, but hereinafter, including the second radar unit 10 and subsequent units, it will be denoted as the q-th radar unit 10. Here, q indicates an index for identifying a plurality of radar units 10 included in the radar device 1, and for example, q = 1 or 2 may be used. In the following description, each element included in the q-th radar unit 10 will be described with "-q" added.

[0075] The generation unit 103 generates TxSig based on, for example, a synchronization signal from the synchronization unit 20. The generated TxSig may be, for example, a predetermined frequency-modulated wave (for example, a frequency chirp signal or a chirp signal). The generation unit 103 outputs the generated chirp signal to the DS unit 101.

[0076] The generation unit 103 includes, for example, a control unit 104, a modulation signal generation unit 105, and a VCO 106. Hereinafter, each component in the generation unit 103 will be described.

[0077] Based on the synchronization signal from the synchronization unit 20, the control unit 104 outputs a control signal to the modulation signal generation unit 105 that controls the transmission timing and transmission pause timing of the radar transmission signal, for example, by counting a reference signal (clock signal) input as the synchronization signal. Regarding the counting of the clock signal, the control unit 104 may detect, for example, the falling or rising edge timing of the clock signal and count the number of clock edges.

[0078] Based on the control signal input from the control unit 104, the modulation signal generation unit 105 periodically generates, for example, a sawtooth-shaped modulation signal. Here, let the transmission period of TxSig be Tr.

[0079] Based on the modulation signal output from the modulation signal generation unit 105, the VCO 106 generates a chirp signal and outputs it to the transmission unit 100 (e.g., DS units 101-1 to 101-Nt) of the radar unit 10 and the reception unit 200 (mixer unit 204 described later).

[0080] For example, based on the synchronization signal, the control unit 104 controls the modulation signal generation unit 105 and the VCO 106 to generate the TxSig. For example, for each radar positioning, the control unit 104 may set parameters (e.g., modulation parameters) related to the chirp signal so that the chirp signal is transmitted N c times per transmission period Tr.

[0081] Hereinafter, a case will be described in which the control unit 104 variably sets the transmission timing of the chirp signal in the BMS configuration using a predetermined pattern and repeatedly transmits the chirp signal. Here, a predetermined transmission period in which the transmission timing is repeated in a predetermined pattern is denoted as "N sw ×Tr". N sw is a predetermined integer value of 2 or more.

[0082] (a) of FIG. 4 shows an example of the chirp signal output from the generation unit 103 of the first radar unit 10, and (b) of FIG. 4 shows an example of the chirp signal output from the generation unit 103 of the second radar unit 10. As shown in FIG. 4, in a plurality of transmission periods (e.g., N sw ×Tr, N SW =2 in FIG. 4), for example, there are a transmission period including a predetermined transmission delay Td and a transmission period not including the transmission delay Td, and these are repeated in a transmission period of 2Tr.

[0083] For example, the control unit 104 alternately sets a transmission period including the transmission delay Td and a transmission period not including the transmission delay Td, and sets them so that the transmission periods including the transmission delay Td do not match between the first radar unit 10 and the second radar unit 10. In the example of FIG. 4, in the odd-numbered transmission periods, the second radar unit 10 includes the transmission delay Td, and the first radar unit 10 does not include the transmission delay Td. In the even-numbered transmission periods, the second radar unit 10 does not include the transmission delay Td, and the first radar unit 10 includes the transmission delay Td. As a result, in the example of FIG. 4, in the odd-numbered transmission periods, the transmission timing of the chirp signal in the second radar unit 10 is delayed by the transmission delay Td (prescribed value) compared to the transmission timing of the chirp signal in the first radar unit 10. In the even-numbered transmission periods, the transmission timing of the chirp signal in the first radar unit 10 is delayed by the transmission delay Td (prescribed value) compared to the transmission timing of the chirp signal in the second radar unit 10.

[0084] Note that the predetermined transmission delay Td (prescribed value) is 0 or more and may be set within a predetermined range (examples will be described later).

[0085] The chirp signal generated by the generation unit 103 is output to the DS unit 101 and the reception unit 200.

[0086] For example, the radar device 1 transmits the chirp signal shown in FIG. 4 every transmission period Tr, and by measuring the reflected wave signal reflected by the target multiple times, the time variation of the positioning result of the target can be detected. Note that hereinafter, out of N c transmission periods T r each transmission period is represented by the index "m". Here, m = 1 to N c is an integer.

[0087] As shown in FIG. 5, the modulation parameters regarding the chirp signal include, for example, the center frequency f c , the frequency sweep bandwidth B w , the sweep start frequency f cstart , the sweep end frequency f cend , the frequency sweep time T sw , and the frequency sweep change rate D mmay be included. Note that D m = B w / T sw is. Also, B w = f cend - f cstart and f c = (f cstart + f cend ) / 2.

[0088] Also, the frequency sweep time T sw corresponds to, for example, the time range (or the range gate, which is also called) for capturing A / D sample data in the A / D conversion unit 207 of the receiving unit 200 described later. The frequency sweep time T sw may be set, for example, to the entire section of the chirp signal shown in FIG. 5 (a) or to a partial section of the chirp signal shown in FIG. 5 (b).

[0089] Note that FIGS. 4 and 5 show an example of an up - chirp waveform in which the modulation frequency gradually increases with time, but a down - chirp may be applied, and regardless of which is used, the present disclosure can obtain the same effect.

[0090] Each chirp signal output from the generation unit 103 is input to, for example, each mixer unit 204 of the receiving unit 200 and each of the Nt DS units 101.

[0091] The DS unit 101 of the q - th radar unit 10 applies a Doppler shift amount (hereinafter also referred to as "DS amount") DOP n (q) to the chirp signal input from the VCO 106 of the generation unit 103. For each transmission period T r of the chirp signal, a phase rotation Φ n,q is applied, and the signal after Doppler shift is output to the transmission antenna 102.

[0092] Also, for example, the number of transmission antennas 102 in each of the q-th radar units 10 may be the same or different. Hereinafter, the number of transmission antennas in the q-th radar unit 10 is denoted as "Nt(q)" (or simply "Nt"). Here, Nt(q) ≥ 1. Also, n = 1 to Nt(q).

[0093] For example, the q-th radar unit 10 may output by applying a predetermined phase rotation φ n,q (m) that gives different Doppler shifts to each transmission antenna 102 used for multi-transmission in the MNS configuration (an operation example will be described later).

[0094] Also, the q-th radar unit 10 may output by applying a predetermined phase rotation Φ n,q (m) that gives Doppler shifts resulting in different DS amount patterns among the radar units 10 performing multi-transmission in the BMS configuration (an operation example will be described later). For example, the pattern of each DS amount (or also referred to as the Doppler shift pattern) applied to the TxSig transmitted from each of the plurality of transmission antennas 102 of the first radar unit 10 may be different from the pattern of each DS amount in the second radar unit 10. The pattern of the DS amount may be set according to at least one of, for example, the Doppler multiplexing interval (or also referred to as the Doppler shift interval, Doppler interval. Also denoted as "DDM interval") and the Doppler multiplexing number (hereinafter also denoted as "DDM number"). Or, the q-th radar unit 10 may output by applying a predetermined phase rotation Φ n,q (m) that gives Doppler shifts resulting in the same DS amount pattern (for example, the same DDM interval) among the radar units 10 performing multi-transmission in the BMS configuration (an operation example will be described later).

[0095] The output signal of the DS unit 101 is amplified to a predetermined transmission power and radiated into space from each transmission antenna 102 (for example, Tx#1 to Tx#Nt).

[0096] [Configuration example of the receiving unit 200] In FIG. 3, the receiving unit 200 includes Na receiving antennas 202 (for example, Rx#1 to Rx#Na) and constitutes an array antenna. The receiving unit 200 also includes Na system processing units 201, a CFAR (Constant False Alarm Rate) unit 210, a separation unit 211, a determination unit 212, and an angle measurement unit 213.

[0097] Here, the number of receiving antennas 202 in each of the qth radar units 10 may be the same or different. Hereinafter, the number of receiving antennas in the qth radar unit 10 is denoted as "Na(q)" (or simply "Na"). Here, Na(q) ≥ 1.

[0098] The system processing unit 201 may be provided corresponding to each of, for example, Na(q) receiving antennas 202. Also, the CFAR unit 210, the separation unit 211, and the angle measurement unit 213 may be provided corresponding to each of, for example, the q radar units 10.

[0099] Each of the Na(q) receiving antennas 202 receives a reflected wave signal obtained by reflecting a TxSig transmitted from each of the plurality of radar units 10 by a target (for example, a reflecting object including a radar measurement target), and outputs the reflected wave signal as a received signal to the corresponding system processing unit 201.

[0100] Each system processing unit 201 includes a receiving radio unit 203 and an analysis unit 206.

[0101] The receiving radio unit 203 includes a mixer unit 204 and an LPF (low pass filter) 205. In the receiving radio unit 203, the mixer unit 204 mixes the received reflected wave signal (received signal) with the chirp signal generated by the generation unit 103. Also, by passing the output of the mixer unit 204 through the LPF 205, a beat signal having a frequency corresponding to the delay time of the reflected wave signal within the passband of the LPF 205 is extracted. For example, the difference frequency between the frequency of the transmission signal (transmission frequency modulation wave) and the frequency of the received signal (received frequency modulation wave) is obtained by the LPF 205 as the beat frequency (or beat signal).

[0102] Here, signals outside the passband of the LPF 205 are attenuated and not received by the receiving unit 200.

[0103] In FIG. 3, the analysis unit 206 of each system processing unit 201-z (where z is any one of 1 to Na(q)) includes an A / D conversion unit 207, a beat analysis unit 208, and a Doppler analysis unit 209 (also referred to as the "DA unit").

[0104] The signal output from the LPF 205 (for example, a beat signal) is converted in the analysis unit 206 by the A / D conversion unit 207 into discrete sample data discretely sampled.

[0105] The beat analysis unit 208 performs FFT (Fast Fourier Transform) processing on N discrete sample data obtained in a predetermined time range (range gate) every transmission period T. r Here, the range gate may be set to the frequency sweep time T. data As a result, in the analysis unit 206, a frequency spectrum in which a peak appears at the beat frequency corresponding to the delay time of the reflected wave signal (radar reflected wave) is output. Note that during the FFT processing, the beat analysis unit 208 may multiply, for example, a window function coefficient such as a Han window or a Hamming window. By using the window function coefficient, side lobes generated around the beat frequency peak can be suppressed. sw z

[0106] Here, the beat frequency response (hereinafter, also referred to as the "BF response") output from the beat analysis unit 208 in the z-th analysis unit 206 obtained by transmitting the m-th chirp pulse of the chirp signal is represented as "RFT z (f b , m)". Here, f b represents the beat frequency index and corresponds to the index (bin number) of the FFT. For example, f b = 0, ~, N data / 2 - 1, z is an integer from 1 to Na, and m is from 1 to N Cis an integer. The beat frequency index f b The smaller the value, the smaller the delay time of the reflected wave signal, indicating a beat frequency where the distance to the target is short (for example).

[0107] For example, when the mixer unit 204 uses a quadrature mixer that outputs a quadrature component in addition to an in-phase component, the negative beat frequency index (bin number) f b =-N data / 2 to -1 represents a negative distance. Here, in the received signal of the radar reflected wave in the MNS configuration, for example, f b =0, ~, N data / 2 - 1, and a negative distance (f b <0) does not occur. Therefore, for example, by setting the transmission delay Td so that the received signal of the radar reflected wave in the BMS configuration is detected at the negative beat frequency index (bin number) f b =-N data / 2 to -1, the radar device 1 can separate and detect the received signal of the radar reflected wave in the BMS configuration from the received signal of the radar reflected wave in the MNS configuration (hereinafter also referred to as "distance separable").

[0108] For example, taking the radar reflected wave from the maximum distance assumed in the BMS configuration as Rmax BMS and the maximum assumed transmission timing error (including frequency error) as TE max when, the transmission delay Td may be set as in the following equation (1). Thereby, the received signal of the radar reflected wave in the BMS configuration and the received signal of the radar reflected wave in the MNS configuration are distance separable.

Equation

[0109] Here, B w represents the frequency sweep bandwidth within the range gate in the chirp signal.

[0110] For example, TE max or RmaxBMS When it is relatively large, B w can be adjusted to be smaller so that Equation (1) can be satisfied. Note that when adjusting B w , B w may become smaller, and the range resolution may decrease. In this case, transmission by FDM in the first radar unit 10 and the second radar unit 10 using a chirp signal that can obtain high range resolution, and B w is set to be small in order to satisfy the transmission delay condition shown in Equation (1). Transmission in which simultaneous transmission of the first radar unit 10 and the second radar is performed using a chirp signal (for example, the transmission shown in FIG. 4) may be periodically or adaptively switched in combination.

[0111] Also, when TE max or Rmax BMS is relatively large, N data can be adjusted to be larger so that Equation (1) can be satisfied. Note that when adjusting N data , N data may become larger, and the chirp transmission period Tr may become longer, resulting in a decrease in the maximum detectable Doppler frequency. In this case, transmission by FDM in the first radar unit 10 and the second radar unit 10 using a chirp signal that increases the maximum Doppler frequency (for example, shortening the transmission period Tr), and the transmission period Tr (or N data ) is set to be large in order to satisfy the transmission delay condition shown in Equation (1). Transmission in which simultaneous transmission of the first radar unit 10 and the second radar unit 10 is performed using a chirp signal (for example, the transmission shown in FIG. 4) may be periodically or adaptively switched in combination.

[0112] In this way, the transmission period that enables distance separation is a case where the transmission timing of the chirp signal of the other radar unit 10 is earlier than the transmission timing of the chirp signal of the own radar unit 10 (for example, a transmission period in which a transmission delay Td is included in the transmission of the chirp signal of the own radar unit 10). For example, in FIG. 4, in the odd-numbered transmission periods, the second radar unit 10 can separate the received signal of the radar reflected wave in the MNS configuration and the received signal of the radar reflected wave from the first radar unit 10 in the BMS configuration in terms of distance. On the other hand, in FIG. 4, the first radar unit 10 can detect the received signal of the radar reflected wave in the MNS configuration in the odd-numbered transmission periods. When there is a possibility that the received signal of the reflected wave from the second radar unit 10 in the BMS configuration is mixed due to the setting of Td, these signals may be separated (the operation example will be described later).

[0113] Also, for example, in FIG. 4, in the even-numbered transmission periods, the first radar unit 10 can separate the received signal of the radar reflected wave in the MNS configuration and the received signal of the radar reflected wave from the second radar unit 10 in the BMS configuration in terms of distance. On the other hand, in FIG. 4, the second radar unit 10 can detect the received signal of the radar reflected wave in the MNS configuration in the even-numbered transmission periods. When there is a possibility that the received signal of the reflected wave from the first radar unit 10 in the BMS configuration is mixed due to the setting of Td, these signals may be separated (the operation example will be described later).

[0114] Note that the setting of the transmission delay Td is not limited to the range of the above formula (1), and it may be set as in the following formula (2).

Equation

[0115] In this case, the received signal of the radar reflected wave in the MNS configuration is, for example, f b =0, ~, N data / 2 - 1, and it does not become a negative distance (f b <0). On the other hand, the received signal of the radar reflected wave in the BMS configuration has a negative index (bin number) f b =-Ndata In addition to being detected when in / 2 to -1, f b = 0, ~, N data There is also a possibility of being detected at / 2 - 1. Such a transmission delay Td is hereinafter also referred to as "separable by half distance".

[0116] When the transmission delay Td is set according to the half - distance separation condition, f b = 0, ~, N data At / 2 - 1, there may be a mixture of the received signal of the reflected wave of the own radar unit 10 in the MNS configuration and the received signal of the reflected wave from the other radar unit 10 in the BMS configuration. Therefore, the radar device 1 is expected to separate these signals. For example, when the transmission delay Td is set according to the half - distance separation condition, in the setting of the Doppler multiplexing interval in the DS unit 101 described later, the DDM interval between the plurality of radar units 10 may be set so as to satisfy the setting condition (2). With such a setting, by utilizing the fact that the DDM intervals between the plurality of radar units 10 are different in the CFAR unit 210 and the separation unit 211 described later, it becomes possible to discriminate between the received signal of the own radar reflected wave in the MNS configuration and the received signal of the reflected wave from the other radar in the BMS configuration (the operation example will be described later).

[0117] Also, the beat frequency index f b In the case of the MNS configuration, it may be converted into the distance information R(f b ) using Equation (3), and in the case of the BMS configuration, using Equation (4). Therefore, hereinafter, the beat frequency index f b is referred to as the "distance index f b " (the distance index is also described as "R - Index").

Equation

Equation

[0118] Here, B wrepresents the frequency sweep bandwidth within the range gate in the chirp signal, and C0 represents the speed of light.

[0119] The DA unit 209 of the z-th analysis unit 206 performs Doppler analysis for each R-Index using the BF response RFT C obtained by transmitting the chirp pulse N z (f b , m) (for example, m = 1 to N C ).

[0120] Note that hereinafter, as shown in FIG. 4, an operation example of the DA unit 209 when the application of the transmission delay Td alternates every transmission period Tr among radars having a BMS configuration will be described.

[0121] The z-th DA unit 209 performs Doppler analysis for each R-Index using the BF response obtained from the received signal in the transmission period in which the above-described distance separation is possible among the BF responses RFT C obtained by transmitting the chirp pulse N z (f b , m) (for example, in the example of FIG. 4, for the DA unit 209 in the first radar unit 10, the BF response when m is even, and for the DA unit 209 in the second radar unit 10, the BF response when m is odd).

[0122] Hereinafter, the DA unit 209 (in FIG. 3, the Doppler analysis unit 209-1) that performs Doppler analysis using such a reflected wave signal is also referred to as the "first Doppler analysis (DA) unit 209" or the "mono / multi separation reception Doppler analysis (DA) unit".

[0123] Further, the DA unit 209 performs Doppler analysis for each R-Index using the BF response obtained from the received signal in the transmission period in which distance separation is not possible (for example, in the example of FIG. 4, for the DA unit 209 in the first radar unit 10, the BF response when m is odd, and for the DA unit 209 in the second radar unit 10, the BF response when m is even).

[0124] Hereinafter, the DA unit 209 (in FIG. 3, Doppler analysis unit 209-2) that performs Doppler analysis using reflected wave signals with a non-separable transmission period is also referred to as the "second Doppler analysis (DA) unit 209" or the "mono / multi mixed reception Doppler analysis (DA) unit".

[0125] For example, the DA unit 209 of the q-th radar unit 10 has N VFT =N c / N sw When the value of is a power of 2, if FFT processing is applied in Doppler analysis, the FFT sizes of the first DA unit 209 (mono / multi separated reception DA unit) and the second DA unit 209 (mono / multi mixed reception DA unit) are N VFT and the maximum DFreq at which no aliasing occurs derived from the sampling theorem is ±1 / (2N sw T r ). Also, the DFreq interval of the DFreq index (also called "DF-Index") f s is 1 / (N c ×T r ) and the range of f s is f s = -N VFT / 2, ~, 0, ~, N VFT / 2 - 1.

[0126] For example, among the DA units 209 in the z-th analysis unit 206 of the q-th radar unit 10, the output VFT z,q Sep (f b , f s ) of the mono / multi separated reception DA unit is shown in the following equation (5), and the output VFT z,q Mix (f b , f s ) of the mono / multi mixed reception DA unit is shown in the following equation (6). Here, j is the imaginary unit, z is an integer from 1 to Na(q), and q = 1, 2. Also, the BF response output from the beat analysis unit 208 in the q-th radar unit 10 is "RFT z,q (f b, m)」. The same applies hereinafter. Here, mod(x,y) is the remainder operator and outputs the remainder when the integer x is divided by the integer y. Here, the output VFT of the mono / multi separation reception DA unit z,q Sep (f b , f s ) where f b = -N data / 2, ~, -1 are reflected wave signals according to the BMS configuration, and f b =0, ~, N Data / 2-1 outputs the Doppler analysis result of the reflected wave signal according to the MNS configuration.

Number

Number

[0127] The processing in each component of the analysis unit 206 has been described above.

[0128] In FIG. 3, the CFAR unit 210 of the q-th radar unit 10 may include, for example, a first CFAR unit 210-q (or denoted as CFAR unit 210-1-q) corresponding to the separated reception signals of the MNS configuration and the BMS configuration in a transmission period separable by distance, and a second CFAR unit 210-q (or denoted as CFAR unit 210-2-q) corresponding to the mixed reception signals of the MNS configuration and the BMS configuration in a transmission period not separable by distance.

[0129] The first CFAR unit 210-q uses the outputs from the first DA units 209 (mono / multi separation reception DA units) of the first to Na(q)-th analysis units 206 to perform CFAR processing (e.g., adaptive threshold determination) and extract the R-Index and DF-Index that give local peak signals. Hereinafter, among the local peak signals in the received signals of the MNS configuration and the BMS configuration detected with distance separation, the R-Index according to the MNS configuration is denoted as "f bp Mono ", and the R-Index according to the BMS configuration is denoted as "f bp BMSis denoted as "", and the DF-Index based on the MNS configuration is "f" sp Mono is denoted as "", and the DF-Index based on the BSM configuration is "f" sp BMS is also denoted as "".

[0130] The second CFAR unit 210-q performs CFAR processing using the output from the second DA unit 209 (mono / multi mixed reception DA unit) of the first to Na(q)-th analysis units 206, and gives local peak signals R-Index (hereinafter, also denoted as f bp Mix ) and DF-Index (hereinafter, also denoted as f sp Mix ) are extracted. Note that f sp Mono , f sp BMS and f sp Mix may include DF-Indices for the number of Doppler multiplicities.

[0131] For example, the first CFAR unit 210-q uses the output of the first DA unit 209 of the first to Na(q) analysis units 206 to obtain f b = 0, ~, N Data / 2 - 1, selectively extracts the local received power peak of the reflected wave signal (received signal, or also called the reflected wave signal in the MNS configuration) by the TxSig from the q-th radar unit 10 as a distance-separated MNS configuration. Also, the first CFAR unit 210-q uses the output of the first DA unit 209 of the first to Na(q) analysis units 206 to obtain f b = -N data / 2, ~, -1, selectively extracts the local peak of the reflected wave signal by the TxSig from the qe-th radar unit 10 as a distance-separated BMS configuration. For example, the first CFAR unit 210-q performs CFAR processing with an adaptive threshold determination after power addition at intervals that match the DDM interval set for the TxSig from the q-th radar unit 10 with respect to the Doppler analysis result of the reflected wave signal in the MNS configuration, and gives local power peaks f bp Mono and f spMono may be extracted and output to the first separation unit 211. Also, for example, the first CFAR unit 210-q performs a CFAR process of performing an adaptive threshold determination after power addition at intervals that match the DDM interval set for the TxSig from the qe-th radar unit 10 with respect to the Doppler analysis result of the reflected wave signal by the BMS configuration, and gives a local power peak f bp BMS and f sp BMS may be extracted and output to the first separation unit 211 (operation examples will be described later).

[0132] Note that when the transmission delay Td is set according to the half-distance separation possible condition, the first CFAR unit 210-q, f b = 0, ~, N Data / 2 - 1, selectively extracts including the local peak of the reflected wave signal by the TxSig from the qe-th radar unit 10 as the BMS configuration. For example, the first CFAR unit 210-q performs a CFAR process of performing an adaptive threshold determination after power addition at intervals that match the DDM interval set for the TxSig from the qe-th radar unit 10 with respect to the Doppler analysis result of the reflected wave signal by the BMS configuration, and gives a local power peak f bp BMS and f sp BMS may be extracted and output to the first separation unit 211. Also, when the DDM intervals between the plurality of radar units 10 are set to satisfy the setting condition (2) described later, the first CFAR unit 210-q can utilize the fact that the DDM intervals between the plurality of radar units 10 are different to discriminate between the received signal of the self-radar reflected wave in the MNS configuration and the received signal of the reflected wave from other radars in the BMS configuration and perform a CFAR process.

[0133] Note that the transmission unit of the MNS configuration in the q-th radar unit 10 is the transmission unit 100 of the q-th radar unit 10. Similarly, the transmission unit of the MNS configuration in the qe-th radar unit 10 is the transmission unit 100 of the qe-th radar unit 10. Also, the transmission unit of the BMS configuration in the q-th radar unit 10 is the transmission unit 100 of the qe-th radar unit 10. Similarly, the transmission unit of the BMS configuration in the qe-th radar unit 10 is the transmission unit 100 of the q-th radar unit 10. Note that the q-th radar unit 10 and the qe-th radar unit 10 are different radar units. For example, when q = 1, qe = 2, and when q = 2, qe = 1.

[0134] Also, for example, the 2nd CFAR unit 210-q selectively extracts a local received power peak of a reflected wave signal (hereinafter referred to as a reflected wave signal in the BMS configuration) by the TxSig from the qe-th radar unit 10 as a BMS configuration, using the output of the 2nd DA unit 209 of the 1st to Na(q)-th analysis units 206.

[0135] For example, the 2nd CFAR unit 210-q performs a CFAR process of performing an adaptive threshold determination after power addition at an interval that matches the DDM interval set for the TxSig from the qe-th radar unit 10 different from the q-th radar unit 10, and gives a local power peak f bp Mix and f sp Mix are extracted and output to the 2nd separation unit 211 (the operation example will be described later).

[0136] Note that the extraction of the local received power peak of the reflected wave signal (hereinafter referred to as the reflected wave signal in the MNS configuration) by the TxSig from the q-th radar unit 10 as an MNS configuration, using the output of the 2nd DA unit 209 of the 1st to Na(q)-th analysis units 206, results in the result of the 1st CFAR unit 210-q, so it may not be extracted by the 2nd CFAR unit 210-q.

[0137] Also, when the DDM interval set for the TxSig from the q_e radar unit 10 matches the DDM interval set for the TxSig from the q radar unit 10, there is a possibility that the reflected wave signal in the MNS configuration is also detected. In such a case, for example, in the second CFAR unit 210-q, f bp Mono and f sp Mono will also be included in the extraction (the operation example will be described later). On the other hand, when the DDM interval set for the TxSig from the q_e radar unit 10 is different from the DDM interval or DDM multiplicity set for the TxSig from the q radar unit 10, even if the reflected wave signals in the MNS configuration are mixed, in the second CFAR unit 210-q, by using the inconsistency of the DDM interval and DDM multiplicity described later, it is possible not to extract the reflected signals in the MNS configuration.

[0138] Also, the transmission unit in the BMS configuration in the first radar unit 10 is the transmission unit 100 of the second radar unit 10. Similarly, the transmission unit 100 in the BMS configuration in the second radar unit 10 is the transmission unit 100 of the first radar unit 10.

[0139] The separation unit 211 of the q radar unit 10 may include a first separation unit 211-q (or represented as separation unit 211-q-1) that performs Doppler multiplex separation (hereinafter also referred to as "DDM separation") processing using the outputs of the first DA unit 209 and the first CFAR unit 210-q, and a second separation unit 211-q (or represented as separation unit 211-q-2) that performs DDM separation processing using the outputs of the second DA unit 209, the second CFAR unit 210-q, and the first separation unit 211.

[0140] For example, the first separation unit 211-q of the q-th radar unit 10 uses the output of the first CFAR unit 210-q to perform DDM separation of the reflected wave signal in the MNS configuration (e.g., corresponding to the first reflected wave signal) and DDM separation of the reflected wave signal in the BMS configuration (e.g., corresponding to the second reflected wave signal). Further, the second separation unit 211-q of the q-th radar unit 10 uses, for example, the output of the first separation unit 211-q and the output of the second CFAR unit 210-q to perform DDM separation of the reflected wave signal in the MNS configuration (e.g., corresponding to the third reflected wave signal) and the reflected wave signal in the BMS configuration (e.g., the fourth reflected wave signal).

[0141] The first separation unit 211-q outputs, for example, information regarding the separated signal to the determination unit 212. The output of the first separation unit 211-q may include, for example, the output from the first DA unit 209.

[0142] Further, the second separation unit 211-q outputs, for example, information regarding the signal obtained by separating the reflected wave signal in the MNS configuration to the determination unit 212. Further, the second separation unit 211-q outputs, for example, information regarding the signal obtained by separating the reflected wave signal in the BMS configuration to the second angle measurement unit 213-2. The output of the second separation unit 211-q may include, for example, the output from the second DA unit 209.

[0143] The information regarding the separated signal may include, for example, the R-Index and the DF-Index corresponding to the separated signal (hereinafter sometimes referred to as separation index information).

[0144] The operation of the separation unit 211-q of the q-th radar unit 10 is related to the operation of the DS unit 101 of the transmission unit 100. Similarly, the operation of the CFAR unit 210-q is related to the operation of the DS unit 101 of the transmission unit 100.

[0145] Hereinafter, an operation example of the DS unit 101 will be described, and then an operation example of the CFAR unit 210-q and an operation example of the separation unit 211-q will be described.

[0146] [Method for Setting DS Quantity] First, an example of a method for setting the DS amount applied in the DS unit 101 will be described.

[0147] Each of the DS units 101 of the first to Nt(q)th in the qth radar unit 10 applies different DS amounts DOP n (q) with a predetermined DDM interval Δfd(q) to the chirp signal input from the generation unit 103 and performs Doppler multiplex transmission (hereinafter, also referred to as "DDM transmission"). At this time, the DDM interval Δfd(q) may satisfy the following setting condition (1) or setting condition (2). When Nt(q) = 1, Doppler shift multiplexing may not be used, and the qth radar unit 10 may not include the DS unit 101. Also, when Nt(q) = 1, the DDM interval is Δfd(q) = 1 / (N sw T r ).

[0148] Setting condition (1): The DDM intervals between the plurality of radar units 10 may be set to the same interval. For example, the intervals between the respective DS amounts applied to the TxSig transmitted from each of the plurality of transmission antennas 102 of the first radar unit 10 and the intervals between the respective DS amounts applied to the TxSig transmitted from each of the plurality of transmission antennas 102 of the second radar unit 10 may be the same (for example, Δfd(1) = Δfd(2)).

[0149] Setting condition (2): The DDM intervals between the plurality of radar units 10 may be set to different intervals. For example, the intervals between the respective DS amounts applied to the TxSig transmitted from each of the plurality of transmission antennas 102 of the first radar unit 10 and the intervals between the respective DS amounts applied to the TxSig transmitted from each of the plurality of transmission antennas 102 of the second radar unit 10 may be different from each other (for example, Δfd(1) ≠ Δfd(2)).

[0150] Hereinafter, an example of setting the DDM interval Δfd(q) will be described.

[0151] Note that hereinafter, the number of DDMs of the qth radar unit 10 is expressed as "N DM (q)", N DMThe case where (q) = Nt(q) will be described, but it is not limited thereto. For example, the radar unit 10 may form a transmission beam by bundling some of the plurality of transmission antennas 102 and perform DDM transmission. In this case, N DM (q) < Nt(q). Also, for example, the DS amount DOP n (q) index n represents the index of the DDM signal, and n = 1 to N DM (q) is an integer. Also, N DM (q) ≥ 1, and q = 1 or 2. Note that when Nt(q) = 1, Doppler shift multiplexing may not be used, and the q-th radar unit 10 may not include the DS unit 101.

[0152] In the present embodiment, the control unit 104 periodically switches the transmission timing in the BMS configuration. Therefore, for example, the DS unit 101 applies a phase rotation that results in a predetermined DS amount to the chirp signal every transmission period (for example, N sw × Tr) of the chirp signal at each transmission timing.

[0153] For example, as shown in FIGS. 4(a) and 4(b), when a transmission period including a predetermined transmission delay Td and a transmission period not including the transmission delay Td alternate every transmission period Tr, the DS unit 101 sets N sw = 2 and applies a phase rotation that results in a predetermined DS amount.

[0154] Here, in the DA unit 209 (mono / multi separation reception DA unit or mono / multi mixing reception DA unit), the range of the DFreq f where no folding derived from the sampling theorem occurs is -1 / (2N d T sw ) ≤ f r < 1 / (2N d T sw )). For example, when the range of the DFreq f where no folding occurs is exceeded, in the DA unit 209, -1 / (2N r ) ≤ f d < 1 / (2N sw T r ) ≤ f d < 1 / (2N sw T r) within the range, the folded frequency is observed. The Doppler shift imparted by the DS unit 101 is -1 / (2N sw T r ) ≦ fd < 1 / (2N sw T r ). Even if it is set outside this range, it is equivalent to being set within the range of -1 / (2N sw T r ) ≦ fd < 1 / (2N sw T r ).

[0155] Therefore, for example, when the DS unit 101 imparts a Doppler shift within the range of -1 / (2N sw T r ) ≦ f d < 1 / (2N sw T r ), the maximum DDM interval (for example, denoted as "Δfdmax") for Nt(q) transmitting antennas 102 (for example, the same number as the DDM number) is Δfdmax = 1 / (T r N sw Nt(q)) = 1 / (T r N sw N DM (q)). The DS unit 101 may set, for example, Δfd(1) and Δfd(2) within the range of Δfdmax. Thereby, the DS unit 101 can set the Doppler shift within the range of 0 to 2π, which is the phase rotation for imparting the Doppler shift.

[0156] As an example, the DDM intervals of the first radar unit 10 and the second radar unit 10 may be set as in the following equation (7).

Equation

[0157] For example, δ q is a parameter that determines the DDM interval. δ1 = δ2 ≧ 0, and N DM (1) = N DMIt may be set to (2). With this setting, the DDM intervals between a plurality of radar units 10 (for example, between the first radar unit 10 and the second radar unit 10) become the same interval, satisfying the setting condition (1) (Δfd(1)=Δfd(2)).

[0158] Or, δ1, δ2≧0, and N DM (1)+δ1≠N DM δ1 and δ2 may be set so as to satisfy (2)+δ2. With this setting, the DDM intervals between a plurality of radar units 10 (for example, between the first radar unit 10 and the second radar unit 10) become different intervals, satisfying the setting condition (2) (Δfd(1)≠Δfd(2)).

[0159] Also, for example, δ1 = δ2 = 0, and N DM (1)≠N DM It may be set to (2). With this setting, the DDM intervals between a plurality of radar units 10 (for example, between the first radar unit 10 and the second radar unit 10) become different intervals, satisfying the setting condition (2) (Δfd(1)≠Δfd(2)).

[0160] Note that each of δ1 and δ2 may be a positive integer or a positive real number. For example, by setting δ1 and δ2 as positive integers, the processing in the first CFAR unit 210 and the second CFAR unit 210 described later can be simplified. Hereinafter, as an example, the case where each of δ1 and δ2 is set to zero or a positive integer will be described, but the present invention is not limited thereto, and a positive real number may be set.

[0161] Also, when a situation where both the radar device 1 and the target are stationary is often assumed, for example, parameters (for example, DDM interval Δfd(q) or δ q ) that make the DS amounts between the first radar unit 10 and the second radar unit 10 coincide may not be included in advance. For example, the parameters may be set so as to satisfy the following formula (8) for all of n1 and n2.

Equation

[0162] With this setting, for example, the DS amount DOP given to the TxSig of the first radar unit 10 n1 (1) and the DS amount DOP given to the TxSig of the second radar unit 10 n2 (2) are set to different values from each other.

[0163] For example, when both the radar device 1 and the target are stationary, the Doppler component becomes zero. Therefore, for example, even when the reflected wave signal by the TxSig from the first radar unit 10 and the reflected wave signal by the TxSig from the second radar unit 10 are included in the same R-Index, the DS amount DOP n (q) is set to be different, so that the radar device 1 can utilize the fact that the detected Doppler components are different and receive them separately.

[0164] Hereinafter, an example of setting the DS amount will be described.

[0165] [Setting Example 1] Setting Example 1 is an example of setting the DS amount that satisfies Setting Condition 1.

[0166] For example, in the formula (7) substituting q = 1, 2, the settings that satisfy Setting Condition 1 are the following Condition a and Condition b.

[0167] Condition a) N DM (1) = N DM In the case of (2): By setting δ1 = δ2 ≧ 0 in the formula (7) substituting q = 1, 2, Δfd(1) = Δfd(2) is obtained. Here, δ1 and δ2 may be integers.

[0168] Condition b) N DM (1) ≠ N DM In the case of (2): Substitute N into the formula (7) substituting q = 1, 2 DM (1) + δ1 = N DM (2) + δ2, then Δfd(1) = Δfd(2) is obtained.

[0169] Here, δ1 and δ2 may be integers.

[0170] When setting δ1 = δ2 = 0 in the formula (7) with q = 1, 2 substituted, the DDM interval can be maximally expanded within the range of the DFreq f d observed in the DA unit 209, which is -1 / (2N sw T r ). ≤ f d < 1 / (2N sw T r ). Therefore, for example, even when the Doppler spectrum has a spread as in the case where the moving speed of the target is not constant and has components such as acceleration, the interference effect between DDM signals can be reduced. On the other hand, in this case, it becomes difficult to expand the observable DFreq using the non-uniformity of the DDM interval as disclosed in Patent Document 3, and the DFreq is -1 / (2 N sw × T r × N DM (1)) ≤ f d < 1 / (2 N sw × T r × N DM (1)). The same applies to the subsequent setting conditions.

[0171] Also, when setting δ1 = δ2 > 0 in the formula (7) with q = 1, 2 substituted, it becomes a condition where the observable DFreq can be expanded using the non-uniformity of the DDM interval as disclosed in Patent Document 3, and the DFreq f d observed in the DA unit 209 within the range of -1 / (2N sw T r ) ≤ f d < 1 / (2N sw T r ) enables the detection of the DFreq of the target. Also, by applying the determination unit 212 described later, the DFreq f d within the range of -1 / (2T r ) ≤ f d < 1 / (2T r ) enables the detection of the DFreq of the target (details will be described later). The same applies to the subsequent setting conditions.

[0172] The following describes an example of the DS amount in Setting Example 1.

[0173] <Setting Example 1-a-1> FIG. 6 shows, as an example, N sw = 2, N DM (1) = N DM (2) = 3, δ1 = δ2 = 1, and when Δfd(1) = Δfd(2) = 1 / (8T r ), a setting example of the Doppler shift of the first radar unit 10 (diagram (a)), and a setting example of the Doppler shift of the second radar unit 10 (diagram (b)) are shown.

[0174] For example, the DS amount DOP n (q) assigned to each transmission antenna 102 (for example, Tx#1 to Tx#3) of the first radar unit 10 and the second radar unit 10 is shown in FIG. 6. Here, n = 1 to 3, q = 1, 2. The DDM interval, which is the interval of the Doppler shift assigned to each transmission antenna, is set to Δfd(1) or an integer multiple of Δfd(1).

[0175] <Setting Example 1-a-2> FIG. 7 shows, as an example, N sw = 2, N DM (1) = N DM (2) = 3, δ1 = δ2 = 2, Δfd(1) = Δfd(2) = 1 / (10T r ), a setting example of the Doppler shift of the first radar unit 10 (diagram (a)), and a setting example of the Doppler shift of the second radar unit 10 (diagram (b)) are shown.

[0176] In FIG. 7, for the setting of each Doppler shift of the first radar unit 10 and the second radar unit 10, a pattern of DS amounts that do not match each other even when cyclically shifted within the DFreq range of ±1 / (2N sw ×Tr) is used. With this setting, even when the received signals of the MNS configuration and the received signals of the BMS configuration are mixed in the subsequent separation unit 211, the received signals of the MNS configuration and the received signals of the BMS configuration can be distinguished, and the separation performance of the radar device 1 can be improved (details will be described later).

[0177] Also, in FIG. 7, between the first radar unit 10 and the second radar unit 10, the DS amount DOP n (q) assigned to each transmission antenna 102 of the first radar unit 10 and the second radar unit 10 is set so that the DS amounts do not match. Here, n = 1 to 3, q = 1, 2. Also, the DDM interval assigned to each transmission antenna is set to Δfd(1) or an integer multiple of Δfd(1).

[0178] <Setting Example 1-b> For example, N sw = 2, N DM (1) = 3, N DM (2) = 2, δ1 = 1, δ2 = 2, it can be set such that Δfd(1) = Δfd(2) = 1 / (8Tr). FIG. 8(a) shows a setting example of the Doppler shift of the first radar unit 10, and FIG. 8(b) shows a setting example of the Doppler shift of the second radar unit 10.

[0179] In FIG. 8, the DDM interval assigned to each transmission antenna is set to Δfd(1) or an integer multiple of Δfd(1). For example, in FIG. 8, in the Doppler shift settings assigned to each transmission antenna of the first radar unit 10 and the second radar unit 10, since the number of DDMs is different (N DM (1) ≠ N DM (2)), patterns of DS amounts that do not match each other are used even when cyclically shifted within the DFreq range of ±1 / (2N sw ×Tr). With the Doppler shift settings in FIG. 8, the separation performance can be improved when the received signals of the MNS configuration and the received signals of the BMS configuration are mixed in the subsequent separation unit 211 (details will be described later).

[0180] [Setting Example 2] Setting Example 2 is a setting example of the DS amount that satisfies Setting Condition 2.

[0181] For example, in the formula (7) with q = 1, 2 substituted, the settings that satisfy Setting Condition 2 of the above-described DDM interval Δfd(q) are the following Conditions a and b.

[0182] Condition a) N DM (1) = NDM (2) case: By setting δ1≠δ2≧0, Δfd(1)≠Δfd(2) is achieved. Here, δ1 and δ2 may be integers. For example, δ1≠δ2 may be set to positive integers.

[0183] Condition b) N DM (1)≠N DM (2) case: By setting δ1=δ2≧0, Δfd(1)≠Δfd(2) is achieved.

[0184] Also, settings that satisfy the following conditions may be used.

[0185] N DM (1)+δ1≠N DM By setting (2)+δ2, Δfd(1)≠Δfd(2) is achieved.

[0186] Here, δ1 and δ2 may be integers. For example, δ1≠δ2 may be set to positive integers. Also, between the first radar unit 10 and the second radar unit 10, it may be set to satisfy, for example, equation (8) so that the DS amounts do not match.

[0187] Hereinafter, examples of the DS amount in setting example 2 will be described.

[0188] <Setting example 2-a> FIG. 9 shows, as an example, Δfd(1)=1 / (6Tr), Δfd(2)=1 / (8Tr), N sw =2, N DM (1)=N DM (2)=2, δ1=1, δ2=2. FIG. 9(a) shows a setting example of the Doppler shift of the first radar unit 10, and FIG. 9(b) shows a setting example of the Doppler shift of the second radar unit 10.

[0189] In the example of FIG. 9, Δfd(1)≠Δfd(2), satisfying the setting condition 2 of the DDM interval Δfd(q).

[0190] <Setting example 2-b> FIG. 10 shows, as an example, Nsw = 2, N DM (1) = 3, N DM (2) Examples of Doppler shift settings for the first radar unit 10 and the second radar unit 10 when = 4, δ1 = δ2 = 0 (Fig. 10(a)) and (Fig. 10(b)) are shown.

[0191] In the example of Fig. 10, Δfd(1) = 1 / (6Tr), Δfd(2) = 1 / (8Tr), and the setting condition 2 for the DDM interval Δfd(q) is satisfied.

[0192] The above is the description of the setting example of the DS amount.

[0193] The DS unit 101 may, for example, set the DS amount corresponding to each transmission antenna 102 using the DDM interval set as above, and apply the phase rotation for imparting the DS amount to the chirp signal every transmission cycle.

[0194] For example, the n-th DS unit 101 of the q-th radar unit 10 applies a different DS amount DOP n (q) to the m-th chirp signal input, and performs a phase rotation Φ n,q (m) and outputs it. As a result, different Doppler shifts are imparted to the transmission signals transmitted from the plurality of transmission antennas 102.

[0195] Here, n is an integer from 1 to Nt(q), m is an integer from 1 to N c and q is 1 or 2.

[0196] For example, for the TxSig from Nt(q) (for example, Nt(q) = N DM (q)) transmission antennas 102, the phase rotation Φ n (m) for imparting the DS amount DOP n,q (q) of the DDM interval Δfd(q) is expressed as in the following equation (9). Also, equation (10) represents the DS amount DOP n (q) of the DDM interval Δfd(q).

Equation

Number

[0197] Here, Φ0 is the initial phase, and ΔΦ0 is the reference Doppler shift phase. Also, α is a coefficient for offsetting the DS amount of each DDM signal, and a real value may be used. For example, when α = 1, the DS amount of the first DDM signal becomes zero.

[0198] As an example, when Nt(1) = Nt(2) = 3, ΔΦ0 = 0, Φ0 = 0, δ1 = 1, and δ2 = 2, the DDM interval is Δfd(1) = 1 / (4N sw T r ), Δfd(2) = 1 / (5N sw T r ) is set. Also, for example, the DS amount DOP n (q) corresponding to the nth transmission antenna 102 is expressed as, for example, in the following equation (11) when α = 1.

Number

[0199] Also, for example, for the mth input chirp signal, the phase rotation Φ n (q) that gives different DS amounts DOP n,q (q) for each of the nth (n = 1, 2, 3) transmission antennas 102 is expressed as in the following equation (12).

Number

[0200] For example, when the first radar unit 10 performs DDM transmission using the number of transmission antennas Nt = 3, the nth DS unit 101 in the first radar unit 10 performs phase rotation Φ for each transmission period Tr with respect to the chirp signal input from the generation unit 103 as in the following equation (13). n,1(m) is assigned. The output of the n-th DS unit 101 is output from, for example, the n-th transmission antenna 102 (Tx#n). Here, cp(t) represents a chirp signal for each transmission period. Here, n = 1, …, Nt (= 3).

Number

[0201] The above is an example of setting the DS amount.

[0202] Next, operation examples of the first CFAR unit 210, the second CFAR unit 210, the first separation unit 211, and the second separation unit 211 in the q-th radar unit 10 corresponding to the operation of the DS unit 101 described above will be described.

[0203] For example, the q-th radar unit 10 separates the first reflected wave signal and the second reflected wave signal from the received signals in the MNS configuration and the BMS configuration in a transmission period in which distance separation is possible, and based on the above first reflected wave signal, separates the third reflected wave signal and the fourth reflected wave signal from the received signals in a transmission period in which distance separation of the received signals in the MNS configuration and the BMS configuration is not possible.

[0204] [Operation Example of First CFAR Unit 210] For example, the first CFAR unit 210 of the q-th radar unit 10 may perform the following operations in order to receive the reflected wave signal in a transmission period in which distance separation is possible.

[0205] For example, the first CFAR unit 210 calculates the power addition value of the outputs from the first DA units 209 of the first to Na(q)-th analysis units 206, and for each R-Index where f b = 0, ~, N Data / 2 - 1, searches for a power peak that matches the DDM interval set in the TxSig of the q-th radar unit 10 as a distance-separated MNS configuration, and performs adaptive threshold processing (CFAR processing) to detect the peak. Similarly, the first CFAR unit 210 calculates f b = -N dataFor each R-Index that becomes / 2, ~, -1, a power peak that matches the DDM interval set for the TxSig of the qeth radar unit 10 as a distance-separated BMS configuration may be searched, and peak detection may be performed by performing adaptive threshold processing (CFAR processing). For example, in peak detection, the first CFAR unit 210 performs a two-dimensional CFAR process consisting of a distance axis and a DFreq axis (corresponding to relative speed), or a CFAR process combining one-dimensional CFAR processes (for example, the process disclosed in Non-Patent Document 3 may be applied).

[0206] Here, for example, in the DS unit 101, when δ q is set to a positive integer, the interval of the DS amount uses the interval of Δfd(q) or an interval that is an integer multiple of Δfd(q). Here, q may be 1 or 2. Therefore, each signal to be DDM can be detected as if folded at the interval of Δfd(q) in the DFreq region of the output of the first DA unit 209. Utilizing such properties, for example, the operation of the first CFAR unit 210 can be simplified as follows.

[0207] The first CFAR unit 210 of the qth radar unit 10, for example, uses a threshold for the power addition value obtained by adding the received power of the reflected wave signal for each range (for example, the range of Δfd(q) or the range of Δfd(qe)) corresponding to each interval of the DS amount respectively given to the TxSig in the DFreq range of the CFAR processing target output from the first DA unit 209, to detect the Doppler peak.

[0208] For example, the first CFAR unit 210, for the output from the first DA unit 209 of the first to Na(q)th analysis units 206, for each R-Index where f b = 0, ~, N Data / 2 - 1, as shown in the following equations (14) and (15), the power addition value PowerDDM Δfd(q) corresponding to the interval of Δfd(q) (for example, corresponding to N q ) by adding the power value Power b FT(f s , f q (f b , f sdc) is calculated, and CFAR processing (hereinafter also referred to as range-separated MNS configuration CFAR) is performed. Also, the first CFAR unit 210, for the outputs from the first DA units 209 of the first to the Na(q)-th analysis units 206, for each R-Index where f b = -N data / 2, ~, -1, as shown in the following equation (16), at intervals of Δfd(qe) (for example, corresponding to N Δfd(qe) ), the power addition value PowerDDM q FT(f b , f s ) obtained by adding the power values Power q (f b , f sdc ) is calculated, and CFAR processing (hereinafter also referred to as range-separated BMS configuration CFAR) is performed. Such CFAR processing is, for example, called "Doppler region compression CFAR processing" and described as "DC-CFAR". Note that DC-CFAR is described in, for example, Patent Document 4, and its detailed description is omitted.

Number

Number

Number

[0209] Here, f sdc =-N VFT / 2,~,-N VFT / 2+N Δfd(q) -1, and N Δfd(q) =round(Δfd(q) / (1 / (T r N c ))), and N Δfd(qe) =round(Δfd(qe) / (1 / (T r N c ))). Also, round(x) is an operator that rounds the real number x and outputs an integer value.

[0210] The first CFAR unit 210 adaptively sets a threshold, for example, by distance-separated MNS-configuration CFAR, and sets f as a received power greater than the threshold bp Mono , f sp Mono and, as f sdcp Mono , and received power information (PowerFT q Mono (f bp Mono , f sdcp Mono +(ndm - 1)×N Δfd(q) )) are output to the first separation unit 211 as received signals of a distance-separated MNS configuration. Here, ndm = 1 to N DM (q)+δ q is an integer. Also, the first CFAR unit 210 adaptively sets a threshold, for example, by distance-separated BMS-configuration CFAR, and sets f as a received power greater than the threshold bp BMS , f sp BMS and, as f sdcp BMS , and received power information (PowerFT q Sep (f bp BMS , f sdcp BMS +(ndm - 1)×N Δfd(qe) )) are output to the first separation unit 211 as received signals of a distance-separated BMS configuration. Here, ndm = 1 to N DM (qe)+δ qe is an integer.

[0211] In addition, when the transmission delay Td is set according to the half-distance separation possible condition, the first CFAR unit 210 performs distance-separated BMS-configuration CFAR processing for selectively extracting, including local peaks of reflected wave signals due to TxSig from the qe-th radar unit 10 in the BMS configuration, for f b = 0, ~, N Data / 2 - 1, and, as f sp BMS and, received power information (PowerFT sdcp BMS , and qSep (f bp BMS , f sdcp mMS +(ndm - 1)×N Δfd(qe) ) are output to the first separation unit 211 as received signals of the distance - separated BMS configuration. Further, when the DDM interval between the plurality of radar units 10 is set so as to satisfy the setting condition (2), the first CFAR unit 210 can utilize the fact that the DDM intervals between the plurality of radar units 10 are different, and even when the received signal of the self - radar reflected wave in the MNS configuration and the received signal of the reflected wave from other radars in the BMS configuration are mixed, these received signals can be discriminated and CFAR processing can be performed.

[0212] [Operation example of the first separation unit 211] The first separation unit 211 of the q - th radar unit 10 performs DDM separation of the first reflected wave signal in the MNS configuration and the second reflected wave signal in the BMS configuration, for example, using the outputs of the first CFAR unit 210 and the first DA unit 209 (for example, the Doppler frequency components of the received signal). For example, the first separation unit 211 of the q - th radar unit 10 inputs f bp Mono , f sdcp Mono , f bp BMS , f sdcp BMS , and based on the received power information, performs the following operations of DDM separation of the received signal in the MNS configuration and DDM separation of the received signal in the BMS configuration.

[0213] (1) DDM separation process of the MNS configuration received signal (when δ q > 0): The first separation unit 211 separates the output of the distance - separated MNS configuration CFAR of the first CFAR unit 210 (f bp Mono , f sdcp Mono , and the received power information PowerFT q Mono (f bp Mono , f sdcp Mono +(ndm - 1)×NΔfd(q) Perform the following processing using ( )

[0214] In the first separation unit 211, for example, the DFreq of the target may be primarily determined assuming that -1 / (2T r N sw ) ≤ f d <1 / (2T r N sw ). Since the DFreq of the target is finally determined in the subsequent determination unit 212, the determination in the first separation unit 211 is also called "temporary determination" or "temporary decision". Also, the reception levels of the top N DM (q) DF - Indexes and the difference between the reception levels of δ DM DF - Indexes different from the top N q DF - Indexes may be significantly different (for example, the difference is equal to or greater than the threshold). For example, the first separation unit 211 compares the reception power information input from the first CFAR unit 210 to temporarily determine the DFreq. Since the operation example of the first separation unit 211 is disclosed in, for example, Patent Document 3, the description of its operation example is omitted here.

[0215] For example, the first separation unit 211 is based on the relationship between δ q DF - Indexes with low reception levels and the top N DM (q) DF - Indexes with high reception power, and associates the DS amount of the transmitted DDM signal with f sdcp Mono +(ndm - 1)×N Δfd(q) and outputs the separation index information f Tx (q)=(f dmlTx#1 (q),~,f dmlTx#NDM (q)) to the second separation unit 211 and the determination unit 212.

[0216] Here, f dmlTx#n (q) indicates the DF - Index of the reflected wave signal by the TxSig from the n - th transmission antenna 102 (Tx#n) of the q - th radar unit 10. In this way, the first separation unit 211 is the R - Index f bp MonoSeparation index information f of the DDM signal in Tx (q), the output of the first DA unit 209 corresponding thereto is regarded as the first reflected wave signal, and is output to the determination unit 212 together with the R-Index information and the separation index information. Hereinafter, the output regarded as the first reflected wave signal is also referred to as the "first separation unit single reception signal output".

[0217] FIG. 11 shows an example of the output (for example, received DFreq) of the DA unit 209 when receiving the reflected wave signal by the TxSig from the first radar unit 10. In FIG. 11, the vertical axis represents the distance axis, and the horizontal axis represents the DFreq axis.

[0218] For example, in the R-Index (fb1 or fb2) shown in FIG. 11, when a DFreq peak component (hereinafter referred to as DF-Peak) that coincides with the interval of Δfd(1) or an integer multiple of the interval of Δfd(1) is observed, the first separation unit 211 discriminates (for example, detects) these DFreq peak components as the reflected wave signal by the TxSig from the first radar unit 10.

[0219] Also, for example, in FIG. 11, δ1 (= 1) DF-Indices with a small reception level are represented by circles, and the top N DM (= 2) DF-Peaks of the received power are represented by crosses and triangles. For example, since the DF-Index (circle) that does not coincide with the interval of Δfd(1) is uniquely determined in the range of -1 / (2T r N sw ) ≦ f d <1 / (2T r N sw ), the first separation unit 211 can uniquely provisionally determine the DFreq of the target in the above range.

[0220] Also, the first separation unit 211 can determine the association between the DFreq and the transmission antenna 102 based on, for example, the magnitude relationship between the DF-Index (circle) and the DF-Peak (cross) that coincides with the interval of other Δfd(1).

[0221] (2) DDM separation processing of the BMS configuration reception signal (δ q> 0 case): The first separation unit 211 is based on the output of the distance separation BMS configuration CFAR of the first CFAR unit 210 (f bp BMS , f sdcp BMS , and the received power information PowerFT q Sep (f bp BMS , f sdcp BMS +(ndm - 1)×N Δfd(qe) )) to perform the following processing.

[0222] In the first separation unit 211, for example, the DFreq of the target may be primarily determined assuming that -1 / (2T r N sw ) ≦ f d <1 / (2T r N sw ) is satisfied. Note that since the DFreq of the target is finally determined in the subsequent determination unit 212, the determination in the first separation unit 211 is also referred to as "temporary determination" or "temporary decision". Also, the difference between the received levels of the top N DM (qe) DF - Indexes of the received power and the received levels of δ DM (qe) DF - Indexes different from the top N qe DF - Indexes may be utilized if they are significantly different (e.g., the difference is greater than or equal to a threshold). For example, the first separation unit 211 compares the received power information input from the first CFAR unit 210 to temporarily determine the DFreq. Note that since an operation example of the first separation unit 211 is disclosed in, for example, Patent Document 3, the description of the operation example is omitted here.

[0223] For example, the first separation unit 211, based on the relationship between the δ qe DF - Indexes with low received levels and the top N DM (qe) DF - Indexes with high received power, associates the DS amount of the transmitted DDM signal with f sdcp BMS +(ndm - 1)×N Δfd(qe) and associates the separation index information f Tx (qe)=(fdmlTx#1 (qe), ~, f dmlTx#NDM Output it to the second separation unit 211 and the determination unit 212 as (qe)).

[0224] Here, f dmlTx#n (qe) indicates the DF-Index of the reflected wave signal by the TxSig from the n-th transmission antenna 102 (Tx#n) of the qe-th radar unit 10. Thus, the first separation unit 211 regards the output of the first DA unit 209 corresponding to the separation index information f Tx (qe) as the second reflected wave signal, and outputs the information regarding the separated first separation unit multi-reception signal to the second separation unit 211. The information regarding the separated signal may include, for example, the R-Index (hereinafter, f bp BMS denoted as) corresponding to the separated second separation unit multi-reception signal, and f bp BMS the separation index information f Tx (qe) of the DDM signal at (hereinafter, f Tx (qe, f bp BMS also denoted as). Further, the output of the first separation unit 211 may include the output from the first DA unit 209. Hereinafter, the output regarded as the second reflected wave signal is also referred to as the "first separation unit multi-reception signal output". Note that the R-Index information (f bp BMS ) outputs the R-Index information corrected by adding the R-Index (for example, Bw×Td) corresponding to the propagation distance (Td×Co) of the transmission delay Td.

[0225] (3) DDM separation processing of the MNS configuration reception signal (δ q =0 case): The first separation unit 211 is the output of the distance separation MNS configuration CFAR of the first CFAR unit 210 (f bp Mono , f sdcp mono , and the received power information PowerFT q Mono (f bp Mono , f sdcp Mono+(ndm-1)×N Δfd(q) ) is used to perform the following processing. In the first separation unit 211, for example, the DFreq of the target may be primarily determined assuming that -1 / (2T r N sw N dm(q) ) ≦ f d <1 / (2T r N sw N dm(q) ). Hereinafter, the first separation unit 211 may perform the same output as in the case of δ q >0.

[0226] [Operation Example of the Second CFAR Unit 210] For example, the second CFAR unit 210 of the q-th radar unit 10 may perform the following operation to receive the reflected wave signal by the TxSig from the qe-th radar unit 10 that transmits the same frequency in the BMS configuration.

[0227] Here, qe represents the radar number of the radar unit 10 different from the q-th radar unit 10. For example, in the case of the first radar unit 10 (q = 1), qe = 2 may be used, and in the case of the second radar unit 10 (q = 2), qe = 1 may be used.

[0228] <When the DDM intervals of the MNS configuration and the BMS configuration are set to the same value in the DS unit 101> The second CFAR unit 210 may, for example, search for a power peak that matches the DDM interval (Δfd(q) = Δfd(qe)) set for the TxSig of each transmission unit 100 of the q-th radar unit 10 and the qe-th radar unit 10 for each R-Index with respect to the power addition value of the outputs from the second DA units 209 of the first to Na(q)-th analysis units 206, and perform peak detection by performing adaptive threshold processing.

[0229] Here, for example, in the DS unit 101, δ qWhen it is set to a positive integer, for the interval of the DS amount, the interval of Δfd(q) or an interval that is an integer multiple of Δfd(q) is used (where q may be 1 or 2, and Δfd(1) may be equal to Δfd(2)). Therefore, each signal to be DDM can be detected as if it is folded at the interval of Δfd(q) in the DFreq region of the output of the second DA unit 209. Utilizing such a property, for example, the DC-CFAR processing described in the operation of the first CFAR unit 210 can be applied. For example, the second CFAR unit 210 uses the output “VFT z,q Sep (f b , f s )” from the second DA unit 209 of the first to the Na(q)-th analysis units 206 as shown in equations (17) and (18) instead of “VFT z,q Mix (f b , f s )” in equations (14) and (15) to calculate the power addition value and perform DC-CFAR processing.

[0230] Hereinafter, the subsequent operations when DC-CFAR processing is used in the CFAR unit 210 will be described. In this case, the second CFAR unit 210 adaptively sets a threshold value, for example, and the R-Index f bp Mix with a received power greater than the threshold value, the DFreq index f sdcp Mix , and the received power information (PowerFT q Mix (f bp Mix , f sdcp Mix +(ndm - 1)×N Δfd(q) )) are output to the second separation unit 211. Here, ndm is an integer from 1 to N DM (q)+δ q . In this way, when the DDM interval set for the TxSig from the qe-th radar unit 10 matches the DDM interval set for the TxSig from the q-th radar unit 10, there is a possibility that the reflected wave signal in the MNS configuration is also detected. Hereinafter, the CFAR processing in such a second CFAR unit 210 is also referred to as “mono & multi-reception CFAR”.

Number

Number

[0231] <(ii) When the DDM intervals between the MNS configuration and the BMS configuration are set to different values in the DS unit 101> In order to receive the fourth reflected wave signal by the TxSig from the qth radar unit 10, the second CFAR unit 210, for example, searches for power peaks that match the DDM interval (Δfd(qe)) set for the TxSig of each transmission unit 100 of the qth radar unit 10 and the qeth radar unit 10 for each R-Index with respect to the power addition value of the output from the second DA unit 209 of the first to Na(q)th analysis units 206, and performs peak detection by performing adaptive threshold processing. Hereinafter, the same CFAR processing in the second CFAR unit 210 described above is performed. By such processing, even if reflected wave signals in the MNS configuration are mixed, in the second CFAR unit 210, it is possible to prevent the reflected signals in the MNS configuration from being extracted by using the inconsistency of the DDM intervals. Similarly, even when the DDM multiplicities are different, it is possible to prevent the reflected signals in the MNS configuration from being extracted. Also, hereinafter, the CFAR processing in the second CFAR unit 210 described above is also referred to as "multi-reception CFAR".

[0232] [Operation example of the second separation unit 211] The second separation unit 211 of the qth radar unit 10 performs DDM separation of the third reflected wave signal in the MNS configuration and the fourth reflected wave signal in the BMS configuration, for example, using the outputs of the first separation unit 211, the second CFAR unit 210, and the second DA unit 209 (for example, the Doppler frequency component of the received signal).

[0233] Here, the first reflected wave signal in the MNS configuration has been separated by the first separation unit 211. Therefore, the second separation unit 211 uses the separation index information f of the DDM signal TxOutput of the second DA unit 209 corresponding to (q) is regarded as the third reflected wave signal and output to the determination unit 212. Hereinafter, the output regarded as the third reflected wave signal is also referred to as the "second separation unit single reception signal output".

[0234] Also, when outputting the second separation unit single reception signal, in the DS unit 101, when the Doppler shift settings in each of the plurality of radar units 10 do not match each other even when cyclically shifted (for example, setting example 1-a-2), when the number of DDMs is different (for example, setting example 1-b), or when the interval of Δfd(q) is set to different values in the BMS configuration (for example, setting example 2-a), the second separation unit 211 may determine whether it matches the pattern of the DS amount of the Doppler shift setting in the above MNS configuration, whether the number of DDMs matches, or whether the interval of Δfd(q) matches. By such determination, the second separation unit 211 can suppress misidentifying the fourth reflected wave signal as the third reflected wave signal.

[0235] On the other hand, the second separation unit 211 outputs the output of the second CFAR unit 210 that does not match (or correspond to) the separation index information f Tx (q) as the fourth reflected wave signal, and outputs the signal after DDM separation to the second angle measurement unit 213. Hereinafter, the output separated by DDM in the second separation unit 211 in this way is also referred to as the "second separation unit multi-reception signal output".

[0236] The latter DDM separation operation is, for example, a DDM separation operation based on the information input from the second CFAR unit 210 that does not match (for example, can be regarded as multi-reception) the separation index information f Tx (q). Therefore, the operation of the second separation unit 211 is the same as the operation using the information input from the second DA unit 209 and the second CFAR unit 210 instead of the information input from the first DA unit 209 and the first CFAR unit 210 in the first separation unit 211. The description of the operation of the second separation unit 211 is omitted.

[0237] For example, the second separation unit 211 is the separation index information f of the DDM signalTx (q) The R-Index f detected by multi-reception CFAR that does not match bp Mix , the DF-Index f sdcp Mix for the received power information (PowerFT q Mix (f bp Mix , f sdcp Mix +(ndm - 1)×N Δfd(qe) )) For, the small δ of the reception level qe number of DF-Indices, and the top N with high received power DM (qe) Based on the relationship between the number of DF-Indices, the DS amount of the transmitted DDM signal, and f sdcp Mix +(ndm - 1)×N Δfd(qe) are associated, and the separation index information f of the DDM signal Tx (qe) is output to the second angle measurement unit 213. Here, f Tx (qe) indicates the DF-Index of the reflected wave signal by the TxSig from each transmission antenna 102 of the qe-th radar unit 10.

[0238] Also, the second separation unit 211 outputs, for example, information regarding the separated second separation unit multi-reception signal to the second angle measurement unit 213. Information regarding the separated signal may include, for example, the R-Index corresponding to the separated second separation unit multi-reception signal (hereinafter denoted as f bp BMS ), and the separation index information f of the DDM signal at f bp BMS (hereinafter also denoted as f Tx (qe) (hereinafter also denoted as f Tx (qe, f bp BMS ). Also, the output of the second separation unit 211 may include the output from the second DA unit 209. Note that the detectable DFreq range is ±1 / (2TrN sw ). Note that the R-Index information (f bp BMSoutputs R-Index information corrected by subtracting the R-Index (for example, Bw×Td) corresponding to the propagation distance (Td×Co) for the transmission delay Td.

[0239] [Operation example of determination unit 212] The determination unit 212 performs determination of DFreq (for example, folding determination of DFreq) based on, for example, the first reflected wave signal and the third reflected wave signal.

[0240] For example, the determination unit 212 determines DFreq based on the phase difference between the received signals of the reflected wave signals in the MNS configuration separated in the first separation unit 211 and the second separation unit 211. Thereby, the observable DFreq range in the radar device 1 can be expanded (for example, expanded to the DFreq range ±1 / (2Tr)), and the maximum detectable DFreq can be increased. Note that the Doppler determination result with the expanded observable DFreq range of the determination unit 212 may be output to, for example, the first angle measurement unit 213 together with the outputs from the first separation unit 211 and the second separation unit 211.

[0241] For example, for DFreq (for example, frequency range ±1 / (2TrN sw )) that can be observed without ambiguity in the DA unit 209, when the relative speed v t of a target with a DFreq range of ±1 / (2Tr) is assumed, the determination unit 212 determines the DFreq (for example, folding of DFreq) of the target based on the phase difference between the output of the first DA unit 209 and the output of the second DA unit 209 in the separation index information f Tx (q) of the DDM signal. Thereby, the detectable DFreq range in the radar device 1 can be expanded (for example, expanded to the frequency range ±1 / (2Tr)).

[0242] For example, when N sw = 2, the frequency range ±1 / (2TrN) corresponding to the separation index of the DDM signal, which is the output of the first separation unit 211 sw) When the DFreq at is fd1, considering the DFreq folding in the frequency range of ±1 / (2Tr), the DFreq of the target may be fd1 or fd1 ± 1 / (N sw Tr).

[0243] For example, the phases of the received signals in the DF-Index corresponding to the DFreq fd1 in the first DA unit 209 and the second DA unit 209 are denoted as φ1(fd1) and φ2(fd1), respectively. In the first radar unit 10, for example, as shown in FIG. 4, the first DA unit 209 and the second DA unit 209 perform Doppler analysis with a period of N sw Tr. Considering that the observation time between the first DA unit 209 and the second DA unit 209 includes a time difference of Tr + Td, the phase difference ΔΦ(fd1) = φ2(fd1) - φ1(fd1) - 2πfd1×(Tr + Td) of φ1(fd1) and φ2(fd1) is ΔΦ(fd1) = ±1 / (N sw Tr)×2π(Tr + Td) = ±(2π / N sw )×(1 + Td / Tr). When this occurs, DFreq folding occurs, and the DFreq is determined to be fd1 ± 1 / (N sw Tr). On the other hand, when ΔΦ(fd1) = 0, DFreq folding does not occur, and the DFreq is determined to be fd1.

[0244] Similarly, in the second radar unit 10, for example, as shown in FIG. 4, the first DA unit 209 and the second DA unit 209 perform Doppler analysis with a period of N sw Tr. Considering that the observation time between the first DA unit 209 and the second DA unit 209 includes a time difference of Tr - Td, the phase difference ΔΦ(fd1) = φ2(fd1) - φ1(fd1) - 2πfd1×(Tr - Td) of φ1(fd1) and φ2(fd1) is ΔΦ(fd1) = ±1 / (N sw Tr)×2π(Tr - Td) = ±(2π / N sw )×(1 - Td / Tr). When this occurs, DFreq folding occurs, and the DFreq is determined to be fd1 ± 1 / (N sw Tr). On the other hand, when ΔΦ(fd1) = 0, DFreq folding does not occur, and the DFreq is determined to be fd1.

[0245] [Operation Example of First Angle Measurement Unit 213] The first angle measurement unit 213 of the q-th radar unit 10 performs angle measurement of a target using the first and third reflected wave signals, for example, based on information (e.g., R-Index f bp (q), and separation index information f Tx (q)) of the DDM signal input from the first separation unit 211 and the second separation unit 211 via the determination unit 212. For example, the first angle measurement unit 213 may perform angle measurement based on the folding determination of DFreq in the determination unit 212.

[0246] For example, the first angle measurement unit 213 extracts the output of the DA unit 209 based on f bp (q) and the separation index information f Tx (q) of the DDM signal, and generates a first q-th virtual reception array correlation vector h q (f bp (q), f Tx (q)) including Nt(q)×Na(q) elements, which is the product of the number of transmission antennas Nt(q) and the number of reception antennas Na(q), and performs angle measurement. Here, for example, q = 1, 2.

[0247] Note that the first angle measurement unit 213 may perform angle measurement for each output of the first and second DA units 209, or may perform angle measurement using the result synthesized by using in-phase addition and power addition.

[0248] Note that there are various angle measurement algorithms. For example, the estimation method disclosed in Non-Patent Document 4 may be used (the same applies to the following angle measurement units).

[0249] By the above operations, the first angle measurement unit 213 of the q-th radar unit 10 may output, for example, the angle measurement value in f bp (q) and the separation index information f Tx (q) as a positioning output.

[0250] Also, f bp(q) may be converted into distance information using Expression (3) and output.

[0251] Also, the f determined by the determination unit 212 bp The DFreq of the target in (q) may be output. Since the amount of DS given in the DS unit 101 during transmission is known for each transmission antenna 102, the first angle measurement unit 213 may output the DFreq of the target based on the separation index information of the DDM signal and the output of the determination unit 212.

[0252] [Operation example of the second angle measurement unit 213] The second angle measurement unit 213 of the q-th radar unit 10 may perform angle measurement of the target based on, for example, the first and second separation unit multi-reception signal outputs (for example, R-Index f bp (qe), and the separation index information f of the DDM signal Tx (qe)) input from the second separation unit 211. For example, the second angle measurement unit 213 may perform angle measurement based on the second and fourth reflected wave signals from the TxSig of the qe-th radar unit 10 separated in the second separation unit 211.

[0253] For example, the second angle measurement unit 213 bp (qe) and the separation index information f of the DDM signal Tx (qe), extracts the output of the DA unit 209, and generates the second virtual reception array correlation matrix H of the second angle measurement unit 213 consisting of an Nt(qe)×Na(q) matrix qe (f bp (qe), f Tx (qe)) and performs angle measurement. Here, for example, qe = 1, 2.

[0254] The second angle measurement unit 213 of the q-th radar unit 10 may output, for example, the direction of departure as an angle measurement value (for example, a positioning output) to the integration unit 30.

[0255] In addition, the second angle measuring unit 213 of the q-th radar unit 10 may output, for example, as an angle measurement value in the direction of arrival of reception, to the integration unit 30 as an angle measurement value (for example, a positioning output). For angle measurement, for example, angle measurement in the BMS configuration described in Non-Patent Document 5 or Non-Patent Document 6 may be used.

[0256] Through the above operations, the second angle measuring unit 213 of the q-th radar unit 10 may output, for example, as a positioning output, f bp (qe), the separation index information f of the DDM signal Tx (qe), the transmission azimuth angle measurement value, and the reception azimuth angle measurement value.

[0257] In addition, f bp (qe) may be converted into distance information using Equation (4) and output.

[0258] Since the amount of DS applied in the DS unit 101 during transmission is known for each transmission antenna 102, the second angle measuring unit 213 may output the DFreq of the target based on the separation index information of the DDM signal.

[0259] Note that since the method for estimating the target position in a radar with a BMS configuration is described in, for example, Non-Patent Document 5 or Non-Patent Document 6, a detailed description of the estimation method will be omitted. In the above example, the case where the angle measuring unit 213 measures the azimuth direction has been described, but the present invention is not limited to this. Depending on the antenna arrangement of each radar, angle measurement in the elevation direction, or angle measurement in both the azimuth direction and the elevation direction is also possible. For example, the angle measuring unit 213 may calculate the azimuth direction and the elevation direction as angle measurement values and output them as a positioning output.

[0260] The operation example of the second angle measuring unit 213 has been described above.

[0261] [Operation example of integration unit 30] In FIG. 3, the integration unit 30 integrates each positioning output of the first angle measuring unit 213 and the second angle measuring unit 213 from the first radar unit 10, and each positioning output of the first angle measuring unit 213 and the second angle measuring unit 213 from the second radar unit 10 to perform positioning of the target.

[0262] In addition, in the integration unit 30, when it is assumed that the transmission signal between the first radar unit 10 and the second radar unit 10 includes a transmission timing error or a frequency error, the distance correction unit 301 in the integration unit 30 corrects the detected distance. Hereinafter, an operation example of the distance correction unit 301 will be described.

[0263] The distance correction unit 301 in the integration unit 30 is f which is the R-Index output in the BMS configuration among the respective positioning outputs from the second angle measurement unit 213 of the first radar unit 10 bp BMS (hereinafter, denoted as f bp BMS (1)) and, among the respective positioning outputs from the second angle measurement unit 213 of the second radar unit 10, f which is the R-Index output in the BMS configuration bp BMS (hereinafter denoted as f bp BMS (2)) as inputs.

[0264] When the transmission timing error (or including a frequency error) between the first radar unit 10 and the second radar unit 10 is known and the variation is small enough to be ignored (for example, in the case of a fixed error), the distance correction unit 301 can perform distance correction based on the distance error caused by the transmission timing error.

[0265] For example, with reference to the transmission time (t1) of the first radar unit 10, the transmission timing error ΔTx of the transmission time (t2) of the transmission signal of the second radar unit 10 is ΔTx = t2 - t1, and when transmitting from the first radar unit 10 and receiving at the second radar unit 10, the distance response obtained in the BMS configuration includes a distance error of -C0ΔTx. Also, when transmitting from the second radar unit 10 and receiving at the first radar unit 10, the distance response obtained in the BMS configuration includes a distance error of C0ΔTx. The distance correction unit 301 converts the distance information into output R(f bp BMS (1) using Equation (4) and outputs R(f bp BMS (1)), and the distance information R(f with the distance error correctedbp BMS (1)) - Output C0ΔTx. Similarly, the distance correction unit 301 outputs f which is the R-Index output in the BMS configuration. bp BMS For (2), convert it to distance information using Equation (4) and output R(f bp BMS (2)) as the distance information R(f bp BMS (2)) + C0ΔTx after correcting the distance error.

[0266] In the case of such a fixed transmission timing error, in the angle measurement unit 213 of each radar unit 10, an operation of correcting the distance error may be performed. Thereby, each radar unit 10 can perform positioning output using the information with the distance error corrected.

[0267] Also, when the transmission timing error (or including the frequency error) between the first radar unit 10 and the second radar unit 10 varies gently (for example, when it is almost a constant transmission timing error within the Nc transmission cycles Tr), the distance correction unit 301 corrects the distance error caused by the transmission timing error as follows. Here, it is assumed that the directivities of the transmission antenna 102 and the reception antenna 202 of each radar unit 10 are the same.

[0268] In this case, since the transmission from the first radar unit 10 and the transmission from the second radar unit 10 are performed simultaneously, the distance responses obtained in the BMS configuration transmitted from the first radar unit 10 and received by the second radar unit 10, and the distance responses obtained in the BMS configuration transmitted from the second radar unit 10 and received by the first radar unit 10 are obtained as substantially the same distance responses. Therefore, for example, even if the transmission timing error ΔTx is unknown, as described above, the distance response obtained in the BMS configuration transmitted from the first radar unit 10 and received by the second radar unit 10 includes a distance error of -C0ΔTx, and the distance response obtained in the BMS configuration transmitted from the second radar unit 10 and received by the first radar unit 10 includes a distance error of C0ΔTx. Thus, by averaging those distance responses, a distance in which the transmission timing error ΔTx is canceled out can be calculated. The distance correction unit 301 corrects the distance error from the target based on the average value of the distance calculated based on f bp BMS (1) and the distance calculated based on f bp BMS (2). The distance correction unit 301 outputs distance information with the distance error corrected. For example, the distance correction unit 301 may output (R(f bp BMS (1)) + R(f bp BMS (2))) / 2, and may output a distance error estimated value corresponding to C0ΔTx (for example, (R((f bp BMS (1)) - R(f bp BMS (2))) / 2, or (R(f bp BMS (2) - R(f bp BMS (1))) / 2).

[0269] Incidentally, when a plurality of R-Indices, which are distance responses obtained in the BMS configuration transmitted from the first radar unit 10 and received by the second radar unit 10, and a plurality of R-Indices, which are distance responses obtained in the BMS configuration transmitted from the second radar unit 10 and received by the first radar unit 10, are respectively output, the relative distance relationship of these plurality of received signals is the same relationship (since a certain distance error is included in the plurality of received signals, it coincides when shifted (offset) by a specific number of Indices (ΔN index ) in the R-Index direction). Therefore, pairs of R-Indices for distance correction between BMSs can be extracted, and the distance correction unit 301 can perform distance correction even when a plurality of R-Index outputs are included. Also, the above-mentioned ΔN index represents an estimated value of the distance error corresponding to C0ΔTx, and the distance correction unit 301 may output, for example, an estimated value of the distance error as R(ΔN index / 2). Further, the distance correction unit 301 may output distance information obtained by correcting the distance error using the estimated value of the distance error.

[0270] By the distance correction in the distance correction unit 301 as described above, the error in the detection distance in the BMS configuration can be reduced. Also, in the integration unit 30, positioning processing in the BMS configuration may be performed using the output of the distance correction in the BMS configuration by the distance correction unit 301 and the output from the second angle measurement unit 213 of each radar unit 10, whereby deterioration of the radar positioning performance can be suppressed.

[0271] For example, the integration unit 30 may perform classification determination of a target based on the consistency between the positioning result of the second angle measurement unit 213 of the first radar unit 10 and the positioning result of the second angle measurement unit 213 of the second radar unit 10, which are the positioning results in the BMS configuration. For example, the integration unit 30 may utilize the fact that the consistency is high for a pole (metal column) and the consistency of reflection points is low for a target with a large lateral width such as a wall.

[0272] Also, for example, when the detection areas overlap in the positioning outputs of the first angle measurement unit 213 of the first radar unit 10, which is the positioning result of the MNS configuration, and the positioning output of the first angle measurement unit 213 of the second radar unit 10, the integration unit 30 may output components with high consistency in the estimation results of both. For example, the integration unit 30 may not output components with low consistency in the estimation results of both. In this case, the integration unit 30 can remove multi-path reflections that become virtual images and the like.

[0273] Note that the integration unit 30 may output the positioning output (or the positioning result) to, for example, a vehicle control device (such as an ECU) in the case of an in-vehicle radar (not shown) or an infrastructure control device in the case of an infrastructure radar.

[0274] As described above, in this embodiment, the radar device 1 includes a first radar unit 10 that transmits a first radar transmission signal and a second radar unit 10 that transmits a second radar transmission signal. Here, in a plurality of transmission periods in which the first radar transmission signal and the second radar transmission signal are transmitted, there are a transmission period including a predetermined transmission delay Td and a transmission period not including the transmission delay Td. For example, these transmission periods are set alternately, and are set so that the transmission periods including the transmission delay Td do not match between the first radar unit 10 and the second radar unit 10.

[0275] Thereby, the radar device 1 can receive the received signal of the reflected wave in the MNS configuration and the received signal of the reflected wave in the BMS configuration separately, maintain the radar detection performance (for example, the detectable Doppler detection range) in the MNS configuration, enable simultaneous multiplex transmission between BMSs in addition to the MNS configuration, and obtain the effect of shortening the time required for radar ranging. Therefore, according to this embodiment, the radar device 1 can efficiently detect a target.

[0276] In addition to the above, in a plurality of transmission cycles in which the first radar transmission signal and the second radar transmission signal are transmitted, a transmission cycle including a predetermined transmission delay Td and a transmission cycle not including the transmission delay Td are alternately set. As a result, the radar device 1 can detect a received signal of a reflected wave obtained in the BMS configuration that is transmitted from the first radar unit 10 and received by the second radar unit 10, and a received signal of a reflected wave obtained in the BMS configuration that is transmitted from the second radar unit 10 and received by the first radar unit 10. Then, the distance correction unit 301 can correct a distance error caused by a transmission timing error (including a frequency error) between the first radar unit 10 and the second radar unit 10 by using these detection results, and can suppress deterioration of radar positioning performance in the BMS configuration.

[0277] Regarding the detection of DFreq in the BMS configuration in the present embodiment, the Doppler detection range based on the output of the second separation unit 211 is ±1 / (2TrN sw ) However, when the same target can be regarded as the same in the BMS configuration and the MNS configuration, the Doppler detection result in the MNS configuration may be used. As a result, in the BMS configuration, since Doppler detection is performed based on the output of the determination unit 212, the Doppler detection range can be expanded to ±1 / (2Tr).

[0278] Further, in the present embodiment, as shown in FIG. 4, the control unit 104 has a transmission cycle including a predetermined transmission delay Td and a transmission cycle not including the transmission delay Td in a plurality of transmission cycles in which the first radar transmission signal and the second radar transmission signal are transmitted, and these transmission cycles are alternately set. As an example of a case where the transmission cycles including the transmission delay Td are not matched between the first radar unit 10 and the second radar unit 10 in the BMS configuration, the operations of the first radar unit 10 and the second radar unit 10 have been described, but the present invention is not limited to this.

[0279] Note that, in the present embodiment, as shown in FIG. 4, the control unit 104 has a transmission cycle including a predetermined transmission delay Td and a transmission cycle not including the transmission delay Td in a plurality of transmission cycles in which the first radar transmission signal and the second radar transmission signal are transmitted. In the receiving unit 200 of the radar device 1, Doppler analysis is performed using separate Doppler analysis units 209 for the transmission cycle including the predetermined transmission delay Td and the transmission cycle not including the transmission delay Td. Here, the DS amount DOP n (q) and the Doppler multiplicity DDM number N DM (q), and the DS amount DOP n (q) and the Doppler multiplicity DDM number N DM (q) given by the DS unit 101 in the transmission cycle not including the transmission delay Td have been described for the case where they are set to be the same, but the present invention is not limited to this.

[0280] For example, the DS amount DOP n (q) and the Doppler multiplicity DDM number N DM (q) given by the DS unit 101 in the transmission cycle including the transmission delay Td, and the DS amount DOP n (q) and the Doppler multiplicity DDM number N DM (q) given by the DS unit 101 in the transmission cycle not including the transmission delay Td may be made different.

[0281] For example, the q-th radar unit 10 sets the DS amount DOP n (q) to δ q = 0 and N DM (q) = 2 in the formula (7), and sets the DS amount DOP n (q) to δ q = 0 and N DM (q) = 1 in the formula (7) may be used.

[0282] Alternatively, for example, the q-th radar unit 10 sets the DS amount DOP n (q) to δ in the formula (7)q >0, and N DM (q) is set to 2, and the DS amount DOP given by the DS unit in the transmission cycle not including the transmission delay Td n (q) is δ in Equation (7) q >0, and N DM It may be set such that (q)=1

[0283] With such a setting, in the transmission cycle including the transmission delay Td, the q-th radar unit 10 transmits transmission signals with different DS amounts from each of the plurality of transmission antennas, and in the transmission cycle not including the transmission delay Td, the q-th radar unit 10 transmits a transmission signal from one transmission antenna. As a result, in the transmission cycle where distance separation is possible, in the BMS configuration, the received signal of the reflected wave transmitted from one transmission antenna can be distance-separated. Since DDM multiple transmission is not used, the received power at the beat analysis unit 208 fluctuates less for each transmission cycle, and it is not necessary to smooth the received power. The distance correction unit 301 can obtain the effect of correcting the distance error of the BMS configuration with the DDM basic cycle

[0284] Also, the DS amount DOP given by the DS unit 101 in the transmission cycle including the transmission delay Td n (q) and the Doppler multiplicity DDM number N DM (q) and the DS amount DOP given by the DS unit 101 in the transmission cycle not including the transmission delay Td n (q) and the Doppler multiplicity DDM number N DM Examples of making (q) different from (q) are not limited to the above examples. For example, in the transmission cycle including the transmission delay Td, the q-th radar unit 10 may transmit a transmission signal from one transmission antenna, and in the transmission cycle not including the transmission delay Td, the q-th radar unit 10 may transmit transmission signals with different DS amounts from each of the plurality of transmission antennas

[0285] Further, in the present embodiment, the control unit 104 sets the transmission cycles including a predetermined transmission delay Td and the transmission cycles not including the transmission delay Td alternately between the first radar unit 10 and the second radar unit 10 so as not to match the transmission cycles including a predetermined transmission delay Td. Although the operation example has been described using an example in which these transmission cycles are repeated with a transmission cycle of 2Tr (for example, the example shown in FIG. 4), it is not limited to such a setting. For example, the control unit 104 sets a transmission cycle N sw ×Tr, in which, in a certain transmission cycle, the first radar unit 10 includes the transmission delay Td and the second radar unit 10 does not include the transmission delay Td, and in another transmission cycle, the first radar unit 10 does not include the transmission delay Td and the second radar unit 10 includes the transmission delay Td. Thereby, the effects in the present embodiment can be obtained. For example, the radar device 1 can receive and separate the received signal of the reflected wave in the MNS configuration and the received signal of the reflected wave in the BMS configuration, and due to the distance correction in the distance correction unit 301, even when the transmission timing error (including the frequency error) between the first radar unit 10 and the second radar unit 10 varies within Nc transmission cycles Tr, the error in the detection distance in the BMS configuration can be reduced.

[0286] Hereinafter, other examples (variations) of the operations of the first radar unit 10 and the second radar unit 10 will be described. Note that hereinafter, the operations different from those of the above-described embodiment will be mainly described.

[0287] (Variation 1) In the first embodiment, the configuration example and the operation example when the variation of the transmission timing error (including the frequency error) between the first radar unit 10 and the second radar unit 10 is small (for example, when the variation of the transmission timing error is negligible within Nc transmission cycles Tr) have been described. With such a configuration, the radar device 1 detects the received signal in the MNS configuration at the N C Tr cycle and detects the received signal in the BMS configuration, enabling distance correction due to the transmission timing error (including the frequency error).

[0288] On the other hand, when the variation in the transmission timing error (including the frequency error) between the first radar unit 10 and the second radar unit 10 is large (for example, when the variation in the transmission timing error cannot be ignored within the Nc transmission periods Tr), in the output of the DA unit 209, the Doppler frequency in the received signal of the BMS configuration does not become constant, so it is not detected as a sharp peak, and there is a possibility that the detection accuracy of the transmission timing error (including the frequency error) deteriorates.

[0289] Therefore, in Variation 1, by using the output of the beat analysis unit 208 to detect the transmission timing error (including the frequency error) at a shorter period (for example, the N sw Tr period, or a period that is an integer multiple thereof), the detection accuracy of the transmission timing error (including the frequency error) is improved, and a configuration example for detecting the received signal of the BMS configuration will be described.

[0290] Hereinafter, the configuration diagram of the radar device in Variation 1 will be shown and its operation will be described. FIG. 12 is a block diagram showing a configuration example of the radar device 1a according to Variation 1. In FIG. 12, the description of the same operation as the configuration in FIG. 3 will be omitted, and the different operations will be described.

[0291] By using a configuration different from the configuration in the above-described embodiment as in the radar device 1a shown in FIG. 12, the received signal of the BMS configuration can be detected at the N sw Tr period, or a period that is an integer multiple thereof, and at the same time, distance correction due to the transmission timing error (including the frequency error) becomes possible. Even when the variation in the transmission timing error (including the frequency error) is large, deterioration of the distance detection accuracy of the BMS configuration can be suppressed, and deterioration of the radar positioning performance can be suppressed.

[0292] Note that, in order to separate the received signal of the BMS configuration, the BMS configuration received power calculation unit 401, the BMS configuration CFAR unit 402, and the BMS configuration separation unit 403 shown in FIG. 12 are used. Therefore, as follows, the operations of the first DA unit 209, the first CFAR unit 210, and the first separation unit 211 are different from those in the above-described embodiment.

[0293] The first DA unit 209 in the z-th analysis unit 206 of the q-th radar unit 10 takes the output VFT of the mono & multi separation reception DA unit z,q Sep (f b , f s ) outputs the Doppler analysis result of the reflected wave signal by the MNS configuration. As the operation of the first DA unit 209, the Doppler analysis operation of the reflected wave signal by the BMS configuration does not need to be included. For example, in Equation (5), the first DA unit 209 b =0, ~, N Data / 2 - 1 is used to output the Doppler analysis result of the reflected wave signal by the MNS configuration.

[0294] Also, the first CFAR unit 210 performs the operation of the range separation MNS configuration CFAR process and does not need to perform the operation of the range separation BMS configuration CFAR process.

[0295] The first separation unit 211 performs the operation related to the first separation unit mono reception signal output and does not need to perform the operation related to the first separation unit multi reception signal output. Similarly, the second separation unit 211 performs the operation related to the second separation unit mono reception signal output and does not need to perform the operation related to the second separation unit multi reception signal output.

[0296] Next, an operation example of the BMS configuration received power calculation unit 401, the BMS configuration CFAR unit 402, the BMS configuration separation unit 403, the second angle measurement unit 213 (or, angle measurement unit 213 - 2), and the range correction unit 301 shown in FIG. 12 will be described.

[0297] The BMS configuration received power calculation unit 401 of the q-th radar unit 10 takes, as an input, the BF response obtained from the received signal in the transmission period in which range separation is possible, similar to the BF response input from the beat analysis unit 208 to the first DA unit 209 (mono / multi separation reception DA unit), calculates the received power of the BF response at a predetermined period, and outputs it to the BMS configuration CFAR unit 402 and the BMS configuration separation unit 403 together with the BF response.

[0298] The input BF response RFT in the m1-th transmission period z,q (fb BMS , assuming it is m1), then f b BMS = -N data / 2, ~, -1 are the reflected wave signals due to the BMS configuration. The BMS configuration received power calculation unit 401 calculates the received power of the reflected wave signals due to the BMS configuration, for example, as shown in the following equation (19). [Number]

[0299] Note that the BMS configuration received power calculation unit 401 adds and outputs the received power of the BF response RFT z,q (f b BMS , m1) obtained from the received signals in the transmission period that can be separated by distance. This can reduce the noise power dispersion.

[0300] Also, the BMS configuration received power calculation unit 401 may add and output the received power of the BF responses obtained from the received signals in a plurality of transmission periods that can be separated by distance. For example, the following equation (20) is the BF response RFT obtained from the received signal in the m1-th transmission period that can be separated by distance z,q (f b BMS , m1), and the received power of the BF response RFT sw T r obtained from the received signal in the m2-th transmission period, which is N z,q (f b BMS , m2) after the m1-th period and can be separated by distance. Note that the following equation (20) is used in combination with the addition of the received powers of the outputs of Na analysis units 206. [Number]

[0301] As a result, noise power dispersion can be reduced. Also, when using DDM, since multiple transmission antennas perform simultaneous multiplex transmission while changing their phases, the fluctuation of the received power in the beat analysis unit 208 may increase for each transmission cycle, and an effect of smoothing the received power can be obtained.

[0302] Also, for example, when the q-th radar unit 10 receives in a BMS configuration, the DDM interval given in the DS unit 101 of the q e-th radar unit 10 is, when using Equation (7), the minimum unit of phase rotation is 2π / (N DM (q e)+δ qe ). From this, the period in which the phase rotation becomes 2π ((N DM (q e)+δ qe )×N sw T r period, hereinafter referred to as the DDM basic period) or a period that is an integer multiple of the DDM basic period, the received power of the BF response obtained from the received signals in a plurality of transmission periods in which distance separation is possible may be smoothed.

[0303] Also, when the DDM intervals of the q-th radar unit 10 and the q e-th radar unit 10 are different (Δfd(1)≠Δfd(2)), the BMS configuration received power calculation unit 401 calculates the respective DDM basic periods ((N DM (q)+δ q )×N sw T r period, and (N DM (q e)+δ qe )×N sw T r period) given in the DS units 101 of the q-th radar unit 10 and the q e-th radar unit 10, and may perform smoothing of the received power using the least common multiple. Both the q-th radar unit 10 and the q e-th radar unit 10 can be smoothed with a DDM transmission period (or an integer multiple of the DDM basic period). When using DDM, the fluctuation of the received power for each transmission cycle in the beat analysis unit 208 is suppressed, and distance correction in the distance correction unit 301 becomes possible, and improvement of distance correction accuracy becomes possible. Here, for example, q e = 1, 2.

[0304] Further, according to the variation situation of the transmission timing error (including frequency error) between the first radar unit 10 and the second radar unit 10, the addition times of the received power in the BMS configuration received power calculation unit 401 may be set. For example, when the variation of the transmission timing error is large, the addition of the received power of the BF response obtained from the received signals in a plurality of transmission periods in which distance separation is possible is not performed (for example, Equation (19)), or it may be several times (for example, Equation (20)). Thereby, the distance correction in the distance correction unit 301 can perform error correction following the variation of the transmission timing error (including frequency error), and the distance correction accuracy can be improved.

[0305] The BMS configuration CFAR unit 402 performs CFAR processing (for example, adaptive threshold determination) using the input for each predetermined period from the BMS configuration received power calculation unit 401, and extracts an R-Index that gives a local peak signal. Hereinafter, the local peak signal in the received signal of the BMS configuration detected with distance separation is denoted as the R-Index f bp BMS and represented. The CFAR processing in the BMS configuration CFAR unit 402 performs one-dimensional CFAR processing in the distance direction (for example, the processing disclosed in Non-Patent Document 3 may be applied).

[0306] The BMS configuration separation unit 403 of the q-th radar unit 10 separates the reflected wave signal in the BMS configuration using, for example, the output of the BMS configuration CFAR unit 402 and the output of the BMS configuration received power calculation unit 401 (for example, the range component of the received signal). For example, the BMS configuration separation unit 403 of the q-th radar unit 10 separates and extracts the received signal in the BMS configuration using the input for a predetermined period from the BMS configuration received power calculation unit 401 and the BMS configuration CFAR unit 402. For example, the BMS configuration separation unit 403 uses the output f bp BMS of the BMS configuration CFAR unit 402 to obtain the output from the BMS configuration received power calculation unit 401 that becomes a local peak signal (for example, P RFT (f b BMS , m1) or P RFT (f b BMS, m1, m2) and the BF response (e.g., RFT z,q (f b BMS , m1), etc.) are output to the second angle measurement unit 213.

[0307] The second angle measurement unit 213 of the q-th radar unit 10 uses the output from the BMS component separation unit 403 instead of the output of the second separation unit 211. The second angle measurement unit 213 of the q-th radar unit 10 uses, for example, information input from the BMS component separation unit 403 at predetermined intervals (e.g., the output from the BMS configuration received power calculation unit 401 that becomes a local peak signal (e.g., P RFT (f b BMS , m1), etc.) and the BF response (e.g., RFT z,q (f b BMS , m1), etc.) to perform angle measurement of the target. For example, the second angle measurement unit 213 may perform angle measurement based on the reflected wave signal by the TxSig from the qe-th radar unit 10 separated in the BMS component separation unit 403.

[0308] For example, when using DDM multiplexing, since it is difficult to perform DDM demultiplexing because the second angle measurement unit 213 of the q-th radar unit 10 performs angle measurement processing using the BF response and it is difficult to detect the transmission azimuth direction, the second angle measurement unit 213 of the q-th radar unit 10 may output to the integration unit 30 as the angle measurement value (e.g., positioning output) of the reception azimuth direction using the BF response. The reception azimuth direction using the BF response depends on the BF response used for BMS configuration received power calculation, for example, RFT z,q (f b BMS , m1) utilizes the fact that the phase for each reception antenna is different depending on the arrival direction of the target reflected wave that becomes the received signal. For example, angle measurement in the BMS configuration described in Non-Patent Document 5 or 6 may be used.

[0309] Also, for example, when using TDM multiplexing instead of DDM multiplexing, since the transmission antenna switches in a time division manner, the second angle measuring unit 213 of the q-th radar unit 10 can perform angle measurement processing using a BF response, and may output it to the integration unit 30 as an angle measurement value (for example, a positioning output) including the transmission azimuth direction. The transmission azimuth direction using the BF response is the BF response used for calculating the received power in the BMS configuration, for example, RFT z,q (f b BMS , m1) depends on the emission direction of the target reflected wave that becomes the received signal, and utilizes the fact that the phase is different for each transmission antenna. For example, angle measurement in the BMS configuration described in Non-Patent Document 5 or 6 may be used.

[0310] By the above operations, the second angle measuring unit 213 of the q-th radar unit 10 outputs, for example, as a positioning output, f b BMS 、f b BMS The received azimuth angle measurement value, the transmission azimuth angle measurement value (in the case of TDM multiplexing transmission), and the output from the BMS configuration received power calculation unit 401 that becomes a local peak signal (for example, P RFT (f b BMS , m1) or P RFT (f b BMS , m1, m2) may be output to the integration unit 30 as an angle measurement value (for example, a positioning output).

[0311] The distance correction unit 301 of the integration unit 30 takes the positioning output of the second angle measuring unit 213 from the first radar unit 10 (which is the R-Index output in the BMS configuration and is hereinafter denoted as f bp BMS and hereinafter denoted as f bp BMS (1)) and the positioning output of the second angle measuring unit 213 from the second radar unit 10 (which is the R-Index output in the BMS configuration and is hereinafter denoted as f bp BMS and hereinafter denoted as f bp BMS (2)) as inputs. The distance correction unit 301 performs distance correction processing in the following BMS configuration for each input information at a predetermined cycle from the second angle measuring unit 213 of each radar unit 10.

[0312] Assuming that the transmission timing error (including frequency error) between the first radar unit 10 and the second radar unit 10 varies within Nc transmission periods Tr, the distance correction unit 301 corrects the distance error caused by the transmission timing error as follows. The correction is performed at the minimum period at which the received signals from the respective radar units 10 having the BMS configuration are separated by distance and output, or an integer multiple of that period.

[0313] For example, as shown in FIG. 4, the control unit 104 alternately sets a transmission period including a predetermined transmission delay Td and a transmission period not including the transmission delay Td in a plurality of transmission periods in which the first radar transmission signal and the second radar transmission signal are transmitted, and sets them so that the transmission periods including the transmission delay Td do not match between the first radar unit 10 and the second radar unit 10 in the BMS configuration. As a result, in the beat analysis unit 208, an output obtained by separating the received signals from the respective radar units 10 having the BMS configuration by distance is obtained for each Tr period. By performing such control of the transmission signal, the distance correction unit 301 can correct the distance error caused by the transmission timing error for each Tr period or for a period that is an integer multiple of N Tr periods. sw An output obtained by separating the received signals from the respective radar units 10 having the BMS configuration by distance is obtained for each Tr period. By performing such control of the transmission signal, the distance correction unit 301 can correct the distance error caused by the transmission timing error for each Tr period or for a period that is an integer multiple of N Tr periods. sw For each Tr period or for a period that is an integer multiple of N Tr periods sw the distance error caused by the transmission timing error can be corrected.

[0314] Therefore, when the variation of the transmission timing error (including frequency error) is large, the operation period of the distance error correction in the distance correction unit 301 may be, for example, N Tr periods. Also, when the variation of the transmission timing error (including frequency error) is relatively gentle, the operation period of the distance error correction in the distance correction unit 301 may be, for example, at intervals that are integer multiples of N Tr periods. The operation period of the distance error correction in the distance correction unit 301 can be appropriately set according to the variation situation of the transmission timing error (including frequency error). sw For example, N Tr periods. Also, when the variation of the transmission timing error (including frequency error) is relatively gentle, the operation period of the distance error correction in the distance correction unit 301 may be, for example, at intervals that are integer multiples of N Tr periods. The operation period of the distance error correction in the distance correction unit 301 can be appropriately set according to the variation situation of the transmission timing error (including frequency error). sw at intervals that are integer multiples of N Tr periods. The operation period of the distance error correction in the distance correction unit 301 can be appropriately set according to the variation situation of the transmission timing error (including frequency error).

[0315] Also, when the number of chirp transmissions of the radar device 1 is at least N sw × Tr, the above-described effects can be obtained. For example, when N c ≧ N sw × Tr, N swIt is possible to correct the distance error caused by the transmission timing error at a period that is an integer multiple of the Tr period.

[0316] Here, the directivities of the transmission antenna 102 and the reception antenna 202 of each radar unit 10 may be the same. In this case, since the transmission from the first radar unit 10 and the transmission from the second radar unit 10 are performed simultaneously, the distance response obtained in the BMS configuration transmitted from the first radar unit 10 and received by the second radar unit 10, and the distance response obtained in the BMS configuration transmitted from the second radar unit 10 and received by the first radar unit 10 are assumed to be substantially the same distance response.

[0317] For each input information at a predetermined period from the second angle measuring unit 213 of each radar unit 10, the distance correction unit 301 is the R-Index output f in the BMS configuration. bp BMS (1) and f bp BMS Averages the distances in (1) and (2) and outputs distance information with the distance error corrected. For example, the distance correction unit 301 may output (R(f bp BMS (1)) + R(f bp BMS (2))) / 2, or may output a distance error estimation value corresponding to C0ΔTx (for example, (R(f bp BMS (1)) - R(f bp BMS (2))) / 2, or ((R(f bp BMS (2) - R(f bp BMS (1))) / 2.

[0318] In addition, when a plurality of R-Indexes, which are the distance responses obtained in the BMS configuration transmitted from the first radar unit 10 and received by the second radar unit 10, and a plurality of R-Indexes, which are the distance responses obtained in the BMS configuration transmitted from the second radar unit 10 and received by the first radar unit 10, are respectively output, the relative distance relationship of these plurality of received signals is the same relationship (since a certain distance error is included in the plurality of received signals, a specific number of Indexes (ΔN index)It becomes a relationship that coincides with shifting (offsetting). For this reason, pairs of R-Indices for distance correction can be extracted between BMSs, and the distance correction unit 301 can perform distance correction even when multiple R-Index outputs are included. Also, the above-described ΔN index represents an estimated distance error corresponding to C0ΔTx, and the distance correction unit 301 may output, for example, an estimated distance error of R(ΔN index / 2). Also, the distance correction unit 301 may output distance information with the distance error corrected, in accordance with a predetermined period from the second angle measurement unit 213 of each radar unit 10, using the estimated distance error.

[0319] Due to the distance correction in the distance correction unit 301 as described above, even when the transmission timing error (including frequency error) between the first radar unit 10 and the second radar unit 10 varies within Nc transmission periods Tr, the error in the detected distance in the BMS configuration can be reduced. Also, in the integration unit 30, positioning processing in the BMS configuration may be performed using the output of the distance correction in the BMS configuration by the distance correction unit 301 and the output of the second angle measurement unit 213 from each radar unit 10, whereby deterioration of the radar positioning performance can be suppressed.

[0320] Also, the radar device 1 can receive by separating the received signal of the reflected wave in the MNS configuration and the received signal of the reflected wave in the BMS configuration, maintain the radar detection performance (for example, detectable Doppler detection range) in the MNS configuration, enable simultaneous multiplex transmission between BMSs in addition to the MNS configuration, and obtain the effect of shortening the time required for radar ranging. Therefore, according to the present embodiment, the radar device 1a can efficiently detect a target.

[0321] In addition, in the present embodiment, the control unit 104 sets the transmission cycles including a predetermined transmission delay Td and the transmission cycles not including the transmission delay Td alternately between the first radar unit 10 and the second radar unit 10 so as not to match the transmission cycles including a predetermined transmission delay Td. Although the operation example has been described using an example (for example, the example shown in FIG. 4) in which these transmission cycles are repeated at a transmission cycle of 2Tr, the present invention is not limited to such a setting. The control unit 104 determines the transmission cycle N sw ×Tr in which, in a certain transmission cycle, the first radar unit 10 includes the transmission delay Td and the second radar unit 10 does not include the transmission delay Td, and in another transmission cycle, the first radar unit 10 does not include the transmission delay Td and the second radar unit 10 includes the transmission delay Td. By setting in this way, the effects in the present embodiment can be obtained. For example, the radar device 1a can receive the received signal of the reflected wave in the MNS configuration and the received signal of the reflected wave in the BMS configuration separately, and due to the distance correction in the distance correction unit, even when the transmission timing error (including the frequency error) between the first radar unit 10 and the second radar unit 10 varies within Nc transmission cycles Tr, the error in the detection distance in the BMS configuration can be reduced.

[0322] Also, the radar device 1a has N c transmission cycles T r each of which is represented by an index "m". Here, m = 1 to N c is an integer. Also, N c ≧N sw ×Tr.

[0323] (Variation 2) In the above embodiment, the BMS configuration by the first radar unit 10 and the second radar unit 10 has been described, but the present invention is not limited to this. For example, for the BMS configuration, two or more radar units 10 may be used, and the same effects as those in the above embodiment can be obtained. Similarly, for Variation 1 as well, for example, two or more radar units 10 may be used, and the same effects as those in Variation 1 can be obtained.

[0324] For example, when applying to the above embodiment using three radar units 10, in addition to the MNS configurations of the first radar unit 10, the second radar unit 10, and the third radar unit 10, when applying to the above embodiment the BMS configurations by the first radar unit 10 and the second radar unit 10, and the BMS configurations by the second radar unit 10 and the third radar unit 10, the following operations of the control unit 104 may be performed. By performing the same operations as those in the above-described embodiment for the MNS configurations of the first radar unit 10, the second radar unit 10, and the third radar unit 10, the BMS configurations by the first radar unit 10 and the second radar unit 10, and the BMS configurations by the second radar unit 10 and the third radar unit 10, similar effects can be obtained for each MNS configuration and BMS configuration.

[0325] The control unit 104 has a transmission cycle N in which the transmission timing is repeated in a predetermined pattern sw ×Tr. Among them, in a certain transmission cycle, the transmission chirp signal of the first radar unit 10 includes a transmission delay Td, the transmission chirp signal of the second radar unit 10 does not include the transmission delay Td, and in another transmission cycle, the transmission chirp signal of the first radar unit 10 does not include the transmission delay Td, and the second radar unit 10 includes the transmission delay Td. Further, in still another transmission cycle, the transmission chirp signal of the second radar unit 10 includes the transmission delay Td, and the transmission chirp signal of the third radar unit 10 does not include the transmission delay Td. Also, in another transmission cycle, the transmission chirp signal of the second radar unit 10 does not include the transmission delay Td, and the transmission chirp signal of the third radar unit 10 includes the transmission delay Td. This may be set. Thereby, similar effects to those in the above embodiment can be obtained in the first radar unit 10 and the second radar unit 10. Also, similar effects to those in the above embodiment can be obtained in the second radar unit 10 and the third radar unit 10.

[0326] For example, FIG. 13 shows the transmission cycle N swAmong Tr = 4, in the transmission period m = 4j + 1, the transmission chirp signal of the second radar unit 10 includes the transmission delay Td, the transmission chirp signal of the first radar unit 10 does not include the transmission delay Td, and in the transmission period m = 4j + 2, the transmission chirp signal of the second radar unit 10 does not include the transmission delay Td, the transmission chirp signal of the first radar unit 10 includes the transmission delay Td. Further, in the transmission period m = 4j + 3, the transmission chirp signal of the second radar unit 10 includes the transmission delay Td, the transmission chirp signal of the third radar unit 10 does not include the transmission delay Td, and in the transmission period m = 4(j + 1), the transmission chirp signal of the second radar unit 10 does not include the transmission delay Td, the transmission chirp signal of the third radar unit 10 includes the transmission delay Td. Here, j = 0, 1, ~, (Nc - 1) / 4, and m = 1 ~ Nc.

[0327] Note that in FIG. 13, in the transmission periods m = 4j + 1 and m = 4j + 2, an example where the third radar unit 10 is in a transmission pause of the chirp signal is shown, but the third radar unit 10 may perform transmission in the MNS configuration by a transmission frequency that does not interfere with the first radar unit 10 and the second radar unit 10 (for example, frequency division multiplexing (FDM) transmission with respect to the first radar unit 10 and the second radar unit 10). Similarly, in the transmission periods m = 4j + 3 and m = 4(j + 1), an example where the first radar unit 10 is in a transmission pause of the chirp signal is shown, but the first radar unit 10 may perform transmission in the MNS configuration by a transmission frequency that does not interfere with the second radar unit 10 and the third radar unit 10 (for example, frequency division multiplexing (FDM) transmission with respect to the first radar unit 10 and the second radar unit 10).

[0328] (Variation 3) In the above embodiment, the case where each radar unit 10 individually generates a chirp signal based on the reference signal input from the synchronization unit 20 has been described. However, an embodiment according to the present disclosure can also be applied to the case where a common chirp signal is generated in the synchronization unit 20 and used as the output of the generation unit 103 in each radar unit 10. In this case, since the chirp signals used in each radar unit are phase-synchronized signals, the application of Embodiment 1 is possible, and the same effect can be obtained.

[0329] (Variation 4) In the above embodiment, the case where the processing in the MNS configuration and the processing in the BMS configuration are performed periodically (or regularly) in each transmission period has been described, but the present invention is not limited thereto. For example, the transmission period in which the processing in the BMS configuration (for example, simultaneous transmission from each radar unit 10) is performed (for example, the transmission period in which the transmission delay Td is set) may be set in an aperiodic (or non-regular) part among the plurality of transmission periods in which the radar device 1 transmits a transmission signal. For example, the transmission period in which the transmission processing in the BMS configuration is performed may be set (for example, limited) to another transmission period different from the transmission period in which the transmission processing in the MNS configuration is performed (for example, the transmission period after positioning by the MNS configuration). Thereby, the radar device 1 can detect a target in the BMS configuration in, for example, some transmission periods (for example, a short section in which about 2 to 4 chirp signals are transmitted).

[0330] (Variation 5) In the radar device 1, when a target exists within a predetermined range from the radar device 1, the first radar unit 10 and the second radar unit 10 perform transmission processing in the BMS configuration (for example, simultaneous transmission of the first transmission signal and the second transmission signal), and when no target exists within the predetermined range, it is not necessary to perform the transmission processing in the BMS configuration.

[0331] The transmission period in which the processing in the BMS configuration is performed (for example, the transmission period in which the transmission delay Td is set) may be set when a target exists within a predetermined range from the radar device 1, and it is not necessary to be set when no target exists within a predetermined range from the radar device 1.

[0332] (Variation 6) The frequency bands of the first transmission signal and the second transmission signal in the transmission period in which the transmission processing in the BMS configuration (for example, simultaneous transmission of the first transmission signal from the first radar unit 10 and the second transmission signal from the second radar unit 10) is performed (for example, the transmission period in which the transmission delay Td is set) may be set narrower than the frequency band of the transmission signal in another transmission period in which the transmission processing in the BMS configuration is not performed.

[0333] Further, for example, in a transmission cycle (for example, a transmission cycle in which a transmission delay Td is set) for performing transmission processing in the BMS configuration (for example, simultaneous transmission of a first transmission signal from the first radar unit 10 and a second transmission signal from the second radar unit 10), the transmission times (for example, PRI (Pulse Repetition Interval)) of the first transmission signal and the second transmission signal may be set longer than the transmission times of the transmission signals in other transmission cycles in which transmission processing in the BMS configuration is not performed.

[0334] Thereby, for example, even when the frequency error (or transmission timing error) is large, the radar apparatus 1 can detect a target in the BMS configuration.

[0335] (Variation 7) In the above embodiment, the case of performing DDM multiplexing in the MNS configuration has been described. However, the multiplexing method is not limited to DDM multiplexing, and other multiplexing methods (for example, TDM multiplexing) may be used.

[0336] The above describes one embodiment according to the present disclosure.

[0337] [Other Embodiments] In each of the above-described embodiments, a configuration using a chirp signal as TxSig has been described. However, a signal different from the chirp signal may be used. For example, TxSig may be a pulse compression wave such as an encoded pulse signal. When an encoded pulse signal is used for TxSig, the mixer unit 204 of the receiving radio unit 203 converts the high-frequency received signal into a baseband signal, and instead of the beat analysis unit 208, a correlator (not shown) that correlates with the encoded pulse signal to be transmitted is used, so that the subsequent processing can be performed in the same manner as the processing according to each of the above-described embodiments, and the same effect can be obtained.

[0338] In the radar apparatus according to an embodiment of the present disclosure, the transmitting unit and the receiving unit may be individually arranged at physically separated locations. Further, in the receiving unit according to an embodiment of the present disclosure, the angle measuring unit and other components may be individually arranged at physically separated locations.

[0339] Also, in one embodiment of the present disclosure, for example, the number of transmission antennas, the number of reception antennas, the number of DDMs, the number of radar units, the DDM interval, the parameters related to the DDM interval (e.g., δ q ), the parameters related to the transmission period (e.g., N sw ), the numerical values used for parameters such as transmission delay are just examples and are not limited to those values.

[0340] Although not shown in the drawings, the radar device according to one embodiment of the present disclosure has, for example, a CPU (Central Processing Unit), a storage medium such as a ROM (Read Only Memory) storing a control program, and a working memory such as a RAM (Random Access Memory). In this case, the functions of the above-described respective units are realized by the CPU executing the control program. However, the hardware configuration of the radar device is not limited to such an example. For example, each functional unit of the radar device may be realized as an IC (Integrated Circuit) which is an integrated circuit. Each functional unit may be individually formed into one chip, or may be formed into one chip so as to include a part or all of them.

[0341] As described above, various embodiments have been described with reference to the drawings, but it goes without saying that the present disclosure is not limited to such examples. It is obvious that those skilled in the art can conceive of various modification examples or correction examples within the scope described in the claims, and it is naturally understood that they also belong to the technical scope of the present disclosure. Also, within the scope not departing from the gist of the disclosure, the respective components in the above-described embodiments may be arbitrarily combined.

[0342] Also, the notation "··· unit" in the above-described embodiments may be replaced with other notations such as "··· circuitry", "··· assembly", "··· device", "··· unit", or "··· module".

[0343] In each of the above embodiments, the present disclosure has been described by taking an example of being configured using hardware, but the present disclosure can also be realized by software in cooperation with hardware.

[0344] Also, each functional block used in the description of each of the above embodiments is typically realized as an LSI which is an integrated circuit. The integrated circuit may control each functional block used in the description of the above embodiment and may include an input terminal and an output terminal. These may be formed into individual chips, or may be formed into one chip so as to include some or all of them. Here, an LSI has been described, but depending on the degree of integration, it may also be referred to as an IC, a system LSI, a super LSI, or an ultra LSI.

[0345] Also, the method of integrating into an integrated circuit is not limited to an LSI, and it may be realized using a dedicated circuit or a general-purpose processor and memory. After manufacturing the LSI, an FPGA (Field Programmable Gate Array) which can be programmed, or a reconfigurable processor which can reconfigure the connection or setting of circuit cells inside the LSI may be used.

[0346] Furthermore, if a technology for integrating into an integrated circuit that replaces an LSI appears due to the progress of semiconductor technology or another derived technology, naturally, the functional blocks may be integrated using that technology. Application of biotechnology or the like is a possibility.

[0347] <Summary of the Present Disclosure> A radar device according to a non-limiting example of the present disclosure includes a first radar circuit that transmits a first transmission signal and a second radar circuit that transmits a second transmission signal. In a plurality of transmission periods in which the first transmission signal and the second transmission signal are transmitted, there are included a first transmission period in which the transmission timing of the first transmission signal is delayed by a specified value from the transmission timing of the second transmission signal, and a second transmission period in which the transmission timing of the second transmission signal is delayed by the specified value from the transmission timing of the first transmission signal.

[0348] In the radar device according to a non-limiting embodiment of the present disclosure, in the plurality of transmission periods, the first transmission period and the second transmission period are alternately set.

[0349] In the radar device according to a non-limiting embodiment of the present disclosure, the first radar circuit separates, from the Doppler frequency component of the received signal in the first transmission period, a first reflected wave signal corresponding to the first transmission signal and a second reflected wave signal corresponding to the second transmission signal, and separates, from the Doppler frequency component of the received signal in the second transmission period, a third reflected wave signal corresponding to the first transmission signal based on the first reflected wave signal, and separates a fourth reflected wave signal corresponding to the second transmission signal.

[0350] In the radar device according to a non-limiting embodiment of the present disclosure, the second radar circuit separates, from the Doppler frequency component of the received signal in the second transmission period, a first reflected wave signal corresponding to the second transmission signal and a second reflected wave signal corresponding to the first transmission signal, and separates, from the Doppler frequency component of the received signal in the first transmission period, a third reflected wave signal corresponding to the second transmission signal based on the first reflected wave signal, and separates a fourth reflected wave signal corresponding to the first transmission signal.

[0351] In the radar device according to a non-limiting embodiment of the present disclosure, the first radar circuit separates, from the range component of the received signal in the first transmission period, a reflected wave signal corresponding to the second transmission signal.

[0352] In the radar device according to a non-limiting embodiment of the present disclosure, the second radar circuit separates, from the range component of the received signal in the second transmission period, a reflected wave signal corresponding to the first transmission signal.

[0353] In a radar device according to a non-limiting exemplary embodiment of the present disclosure, a correction circuit that corrects a distance to a target based on an average value of a distance calculated based on a range component of a reflected wave signal corresponding to the second transmission signal in the first radar circuit and a distance calculated based on a range component of a reflected wave signal corresponding to the first transmission signal in the second radar circuit.

[0354] In a radar device according to a non-limiting exemplary embodiment of the present disclosure, the first radar circuit transmits the first transmission signal from a plurality of first transmission antennas, the second radar circuit transmits the second transmission signal from a plurality of second transmission antennas, and an interval between Doppler shift amounts given to the first transmission signals transmitted from respective ones of the plurality of first transmission antennas is different from an interval between Doppler shift amounts given to the second transmission signals transmitted from respective ones of the plurality of second transmission antennas.

[0355] In a radar device according to a non-limiting exemplary embodiment of the present disclosure, in the first transmission period, the first radar circuit transmits the first transmission signals having different Doppler shift amounts from respective ones of the plurality of first transmission antennas, the second radar circuit transmits the second transmission signal from one second transmission antenna, and in the second transmission period, the first radar circuit transmits the first transmission signal from one of the first transmission antennas, and the second radar circuit transmits the second transmission signals having different Doppler shift amounts from respective ones of the plurality of second transmission antennas.

[0356] In a radar device according to a non-limiting exemplary embodiment of the present disclosure, in the first transmission period, the first radar circuit transmits the first transmission signal from one first transmission antenna, the second radar circuit transmits the second transmission signals having different Doppler shift amounts from respective ones of the plurality of second transmission antennas, and in the second transmission period, the first radar circuit transmits the first transmission signals having different Doppler shift amounts from respective ones of the plurality of first transmission antennas, and the second radar circuit transmits the second transmission signal from one of the second transmission antennas.

[0357] In a radar device according to a non-limiting embodiment of the present disclosure, the first transmission period and the second transmission period are set as an aperiodic part among a plurality of transmission periods during which the radar device transmits transmission signals.

[0358] In a radar device according to a non-limiting embodiment of the present disclosure, the first transmission period and the second transmission period are set when a target exists within a predetermined range from the radar device, and are not set when the target does not exist within the predetermined range.

[0359] In a radar device according to a non-limiting embodiment of the present disclosure, the frequency bands of the first transmission signal and the second transmission signal in the first transmission period and the second transmission period are narrower than the frequency bands of the transmission signals in other transmission periods different from the first transmission period and the second transmission period.

[0360] In a radar device according to a non-limiting embodiment of the present disclosure, the transmission times of the first transmission signal and the second transmission signal in the first transmission period and the second transmission period are longer than the transmission times of the transmission signals in other transmission periods different from the first transmission period and the second transmission period.

[0361] In a transmission method of a radar device according to a non-limiting embodiment of the present disclosure, a first transmission signal is transmitted by a first radar circuit of the radar device, and a second transmission signal is transmitted by a second radar circuit of the radar device. In the plurality of transmission periods during which the first transmission signal and the second transmission signal are transmitted, there are included a first transmission period in which the transmission timing of the first transmission signal is delayed by a specified value from the transmission timing of the second transmission signal, and a second transmission period in which the transmission timing of the second transmission signal is delayed by the specified value from the transmission timing of the first transmission signal.

[0362] In a transmission method of a radar device according to a non-limiting embodiment of the present disclosure, the first transmission period and the second transmission period are set alternately in the plurality of transmission periods.

[0363] In the transmission method of the radar device according to a non-limiting embodiment of the present disclosure, by the first radar circuit, from the Doppler frequency component of the received signal in the first transmission period, a first reflected wave signal corresponding to the first transmission signal and a second reflected wave signal corresponding to the second transmission signal are separated, and from the Doppler frequency component of the received signal in the second transmission period, based on the first reflected wave signal, a third reflected wave signal corresponding to the first transmission signal is separated, and a fourth reflected wave signal corresponding to the second transmission signal is separated.

[0364] In the transmission method of the radar device according to a non-limiting embodiment of the present disclosure, by the second radar circuit, from the Doppler frequency component of the received signal in the second transmission period, a first reflected wave signal corresponding to the second transmission signal and a second reflected wave signal corresponding to the first transmission signal are separated, and from the Doppler frequency component of the received signal in the first transmission period, based on the first reflected wave signal, a third reflected wave signal corresponding to the second transmission signal is separated, and a fourth reflected wave signal corresponding to the first transmission signal is separated.

[0365] In the transmission method of the radar device according to a non-limiting embodiment of the present disclosure, by the first radar circuit, from the range component of the received signal in the first transmission period, a reflected wave signal corresponding to the second transmission signal is separated.

[0366] In the transmission method of the radar device according to a non-limiting embodiment of the present disclosure, by the second radar circuit, from the range component of the received signal in the second transmission period, a reflected wave signal corresponding to the first transmission signal is separated.

Industrial Applicability

[0367] The present disclosure is suitable as a radar device for detecting a wide-angle range.

Description of Signs

[0368] 1, 1a Radar device 10 Radar unit 20 Synchronization unit 30 Integration Department 100 Transmission Department 101 Doppler Shift Department 102 Transmission Antenna 103 Generation Department 104 Control Department 105 Modulation Signal Generation Department 106 VCO 200, 200a Receiving Department 201 System Processing Department 202 Receiving Antenna 203 Receiving Radio Department 204 Mixer Department 205 LPF 206 Analysis Department 207 A / D Conversion Department 208 Beat Analysis Department 209 Doppler Analysis Department 210 CFAR Department 211 Separation Department 212 Judgment Department 213 Angle Measurement Department 301 Distance Correction Department 401 BMS Configuration Received Power Calculation Department 402 BMS Configuration CFAR Department 403 BMS Configuration Separation Department

Claims

1. A first radar circuit that transmits a first transmission signal, A second radar circuit that transmits a second transmission signal, It is equipped with, The plurality of transmission cycles in which the first transmission signal and the second transmission signal are transmitted include a first transmission cycle in which the transmission timing of the first transmission signal is delayed by a specified value compared to the transmission timing of the second transmission signal, and a second transmission cycle in which the transmission timing of the second transmission signal is delayed by the specified value compared to the transmission timing of the first transmission signal. Radar device.

2. In the plurality of transmission cycles, the first transmission cycle and the second transmission cycle are set alternately. The radar device according to claim 1.

3. The first radar circuit is, From the Doppler frequency component of the received signal in the first transmission cycle, a first reflected wave signal corresponding to the first transmitted signal and a second reflected wave signal corresponding to the second transmitted signal are separated. From the Doppler frequency component of the received signal in the second transmission cycle, a third reflected wave signal corresponding to the first transmitted signal is separated based on the first reflected wave signal, and a fourth reflected wave signal corresponding to the second transmitted signal is separated. The radar device according to claim 1.

4. The second radar circuit is, From the Doppler frequency component of the received signal in the second transmission cycle, the first reflected wave signal corresponding to the second transmitted signal and the second reflected wave signal corresponding to the first transmitted signal are separated. From the Doppler frequency component of the received signal in the first transmission cycle, a third reflected wave signal corresponding to the second transmitted signal is separated based on the first reflected wave signal, and a fourth reflected wave signal corresponding to the first transmitted signal is separated. The radar device according to claim 1.

5. The first radar circuit is, The reflected wave signal corresponding to the second transmitted signal is separated from the range component of the received signal in the first transmission cycle. The radar device according to claim 1.

6. The second radar circuit is, The reflected wave signal corresponding to the first transmitted signal is separated from the range component of the received signal in the second transmission cycle. The radar device according to claim 1.

7. The system further comprises a correction circuit that corrects the distance to a target based on the average value of the distance calculated in the first radar circuit based on the range component of the reflected wave signal corresponding to the second transmitted signal and the distance calculated in the second radar circuit based on the range component of the reflected wave signal corresponding to the first transmitted signal. The radar device according to claim 1.

8. The first radar circuit transmits the first transmission signal from a plurality of first transmitting antennas. The second radar circuit transmits the second transmission signal from a plurality of second transmitting antennas. The interval between each Doppler shift amount applied to the first transmission signal transmitted from each of the plurality of first transmitting antennas is different from the interval between each Doppler shift amount applied to the second transmission signal transmitted from each of the plurality of second transmitting antennas. The radar device according to claim 1.

9. In the first transmission cycle, the first radar circuit transmits the first transmission signal with different Doppler shift amounts from each of the plurality of first transmitting antennas, and the second radar circuit transmits the second transmission signal from one second transmitting antenna. In the second transmission cycle, the first radar circuit transmits the first transmission signal from one of the first transmitting antennas, and the second radar circuit transmits the second transmission signal from each of the plurality of second transmitting antennas, each with a different Doppler shift amount. The radar device according to claim 1.

10. In the first transmission cycle, the first radar circuit transmits the first transmission signal from one first transmitting antenna, and the second radar circuit transmits the second transmission signal from each of a plurality of second transmitting antennas with different Doppler shift amounts. In the second transmission cycle, the first radar circuit transmits the first transmission signal with different Doppler shift amounts from each of the plurality of first transmitting antennas, and the second radar circuit transmits the second transmission signal from one of the second transmitting antennas. The radar device according to claim 1.

11. The first transmission period and the second transmission period are set to a non-periodic portion of a plurality of transmission periods in which the radar device transmits a transmission signal. The radar device according to claim 1.

12. The first transmission period and the second transmission period are set when a target is within a predetermined range from the radar device, and are not set when the target is not within the predetermined range. The radar device according to claim 1.

13. The frequency bandwidths of the first and second transmission signals in the first and second transmission cycles are narrower than the frequency bandwidths of transmission signals in other transmission cycles different from the first and second transmission cycles. The radar device according to claim 1.

14. The transmission times for the first transmission signal and the second transmission signal in the first and second transmission cycles are longer than the transmission signal transmission times in other transmission cycles different from the first and second transmission cycles. The radar device according to claim 1.

15. The first transmission signal is transmitted by the first radar circuit of the radar device. The second transmission signal is transmitted by the second radar circuit of the radar device. The method of transmission, The plurality of transmission cycles in which the first transmission signal and the second transmission signal are transmitted include a first transmission cycle in which the transmission timing of the first transmission signal is delayed by a specified value compared to the transmission timing of the second transmission signal, and a second transmission cycle in which the transmission timing of the second transmission signal is delayed by the specified value compared to the transmission timing of the first transmission signal. Sending method.

16. In the plurality of transmission cycles, the first transmission cycle and the second transmission cycle are set alternately. The transmission method according to claim 15.

17. The first radar circuit, From the Doppler frequency component of the received signal in the first transmission cycle, a first reflected wave signal corresponding to the first transmitted signal and a second reflected wave signal corresponding to the second transmitted signal are separated. From the Doppler frequency component of the received signal in the second transmission cycle, a third reflected wave signal corresponding to the first transmitted signal is separated based on the first reflected wave signal, and a fourth reflected wave signal corresponding to the second transmitted signal is separated. The transmission method according to claim 15.

18. The second radar circuit, From the Doppler frequency component of the received signal in the second transmission cycle, the first reflected wave signal corresponding to the second transmitted signal and the second reflected wave signal corresponding to the first transmitted signal are separated. From the Doppler frequency component of the received signal in the first transmission cycle, a third reflected wave signal corresponding to the second transmitted signal is separated based on the first reflected wave signal, and a fourth reflected wave signal corresponding to the first transmitted signal is separated. The transmission method according to claim 15.

19. The first radar circuit, The reflected wave signal corresponding to the second transmitted signal is separated from the range component of the received signal in the first transmission cycle. The transmission method according to claim 15.

20. The second radar circuit, The reflected wave signal corresponding to the first transmitted signal is separated from the range component of the received signal in the second transmission cycle. The transmission method according to claim 15.

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