Radar device and radar detection method

Abstract

The invention provides a radar device and a radar detection method. The radar device comprises a transmitting circuit, a transmitting antenna system and a receiving antenna system. The transmitting circuit is used for generating two transmission signals, and the bandwidths of the two transmission signals are different. The transmitting antenna system is used for transmitting the two transmission signals. The receiving antenna system is used for receiving two echo signals, the two echo signals are respectively generated by reflecting the two transmission signals by an external object, and the bandwidths of the two echo signals are different. One of the two transmission signals and one of the two echo signals are used in a first detection mode, and the other of the two transmission signals and the other of the two echo signals are used in a second detection mode. The detection power of the first detection mode is greater than the detection power of the second detection mode.

Description

Technical Field

[0001] This invention relates to radar technology, and more particularly to a radar device and radar detection method. Background Technology

[0002] Radar technology is a means of target detection and tracking, and it is widely used in military, aviation, meteorological and other fields. Radar can be divided into narrow band (NB) and wide band (WB) applications.

[0003] Narrowband radar (e.g., covering a frequency band of 10.5 to 10.55 GHz) has the advantage of a higher allowable transmit power allocation, such as an equivalent isotropic radiated power (EIRP) of approximately +14 dBm, but its disadvantage is that its effective bandwidth is less than 50 MHz. Therefore, narrowband radar has a longer detection range, but its range resolution is coarser.

[0004] Wideband radar (e.g., covering the 7.5 to 8.5 GHz band) has the advantage of a minimum effective bandwidth greater than 500 MHz, but its disadvantage lies in a lower allowable average transmit power distribution, for example, an equivalent isotropic radiated power of approximately 41.3 dBmW per megahertz. Therefore, wideband radar has a shorter detectable range but offers finer range resolution.

[0005] Therefore, it can be seen that narrowband and broadband radars each have their own advantages and disadvantages, and are suitable for different application scenarios. Summary of the Invention

[0006] The radar device of this invention includes (but is not limited to) a transmitting circuit, a transmitting antenna system, and a receiving antenna system. The transmitting circuit generates two transmitted signals with different bandwidths. The transmitting antenna system transmits these two transmitted signals. The receiving antenna system receives two echo signals, which are generated by reflections of the two transmitted signals from external objects and also have different bandwidths. One of the two transmitted signals and one of the two echo signals are used in a first detection mode, and the other of the two transmitted signals and the other of the two echo signals are used in a second detection mode. The detection power of the first detection mode is greater than the detection power of the second detection mode.

[0007] The radar detection method of this invention includes (but is not limited to) the following steps: selecting to execute a first detection mode or a second detection mode. Executing the first detection mode includes: transmitting a first transmission signal; transmitting the first transmission signal; and receiving a first echo signal generated by the reflection of the first transmission signal by an external object. Executing the second detection mode includes: transmitting a second transmission signal with a different bandwidth; transmitting the second transmission signal; and receiving a second echo signal generated by the reflection of the second transmission signal by an external object, wherein the bandwidth of the second echo signal is different from that of the first echo signal. The detection power of the first detection mode is greater than the detection power of the second detection mode.

[0008] The radar device of this invention includes (but is not limited to) a transmitting circuit, a transmitting antenna system, a receiving antenna system, a control circuit, and a selection circuit. The transmitting circuit generates two transmitted signals with different bandwidths. The transmitting antenna system transmits these two transmitted signals. The receiving antenna system includes two receiving antennas, each used to receive two echo signals with different bandwidths generated by reflections of the two transmitted signals from external objects. The control circuit generates one or more control signals. The selection circuit is coupled to the control circuit and the receiving antenna system, and is used to select one of the two receiving antennas to receive one of the two echo signals based on the one or more control signals generated by the control circuit.

[0009] To make the above features and advantages of the present invention more apparent and understandable, specific embodiments are described below in conjunction with the accompanying drawings. Attached Figure Description

[0010] Figure 1 This is a component block diagram of a radar device according to an embodiment of the present invention.

[0011] Figure 2A This is a component block diagram of a radar device according to an embodiment of the present invention.

[0012] Figure 2B This is a component block diagram of a radar device according to another embodiment of the present invention.

[0013] Figure 3A This is a component block diagram of a radar device according to an embodiment of the present invention.

[0014] Figure 3B This is a component block diagram of a radar device according to another embodiment of the present invention.

[0015] Figure 4A This is a schematic diagram of signal and antenna switching according to an embodiment of the present invention.

[0016] Figure 4B This is a schematic diagram of one-dimensional detection according to an embodiment of the present invention.

[0017] Figure 5 This is a schematic diagram of the angle of arrival according to another embodiment of the present invention.

[0018] Figure 6A This is a schematic diagram of signal and antenna switching according to another embodiment of the present invention.

[0019] Figure 6B This is a schematic diagram of two-dimensional detection according to another embodiment of the present invention.

[0020] Figure 7 This is a flowchart of a radar detection method according to an embodiment of the present invention.

[0021] Symbol explanation:

[0022] 10, 10-1~10-4: Radar equipment

[0023] 11: Transmitting circuit

[0024] 12, 12A, 12B: Transmitting antenna system

[0025] 13: Receiving Antenna System

[0026] 14: Receiving circuit

[0027] 15: Control Circuit

[0028] 16: Selection Circuit

[0029] TX1, TX2: Transmitting antennas

[0030] 121, 122, 131, 132: Matching circuits

[0031] RX1, RX2: Receiving antennas

[0032] 161, 162: Switching circuit

[0033] PA: Amplifier

[0034] LNA: Low Noise Amplifier

[0035] 171: Frequency Synthesizer

[0036] 18: Modulator

[0037] 19: Clock Generator

[0038] 20: Processing Unit

[0039] TXMIX, RXIMIX: Mixers

[0040] LPF: Filter

[0041] DAC: Digital-to-Analog Converter

[0042] IFA: Intermediate Frequency Amplifier Circuit

[0043] IFA-1: Intermediate Frequency Amplifier

[0044] IFA-2: Correction Circuit

[0045] IFA-3: Filter

[0046] ADC: Analog-to-Digital Converter

[0047] DO: Baseband signal

[0048] 172: Pulse Generator

[0049] O: External object

[0050] d2: Interval distance

[0051] θ: Angle of arrival

[0052] d2sinθ: Distance difference X, Y: Axes

[0053] FS1~FS4: First signal

[0054] f1~f4: Frequency

[0055] TX SW, RX SW: Control signals

[0056] TRC, TRC2: Transmitter / Receiver Combination

[0057] R: Distance

[0058] S710, S720, S721, S722, S723, S730, S731, S732, S733: Steps Detailed Implementation

[0059] Figure 1 This is a component block diagram of a radar device 10 according to an embodiment of the present invention. Please refer to... Figure 1 The radar device 10 includes, for example, (but is not limited to) a transmitting circuit 11, a transmitting antenna system 12, a receiving antenna system 13, a receiving circuit 14, a control circuit 15, and a selection circuit 16. The radar device 10 can be applied, for example, to meteorological, speed measurement, reversing, terrain observation, and military applications.

[0060] Transmitting circuit 11 is used to generate transmission signals. In one embodiment, transmitting circuit 12 generates two transmission signals with different bandwidths. For example, the first transmission signal (one of the two transmission signals) has a bandwidth of 50 MHz (i.e., corresponding to narrowband), and the second transmission signal (the other of the two transmission signals) has a bandwidth greater than 500 MHz (i.e., corresponding to wideband). In one embodiment, the bandwidth of the first transmission signal is less than the bandwidth of the second transmission signal.

[0061] In one embodiment, the transmitting circuit 11 generates a transmission signal based on a first signal. The first signal has a periodic variation. In one embodiment, the frequency of the first signal varies with time within its sweep period. For example, the first signal is a periodic sawtooth wave, triangular wave, or other carrier signal used in frequency-modulated continuous wave (e.g., linear, geometric, or other chirp signals). Within the period, the frequency of the first signal may gradually increase and / or gradually decrease. In another embodiment, the first signal is a pulse signal. For example, it has a peak or valley within a specific time interval (e.g., 2, 5, or 110 nanoseconds (ns)). A pulse signal can be generated at each interval of one cycle.

[0062] The transmitting antenna system 12 is used to transmit a transmission signal. That is, the transmitted electromagnetic waves carry the transmission signal of the radar device 10. In one embodiment, since the first signal has a periodic variation, the transmission signal also has a corresponding periodic variation. In one embodiment, for a pulse signal, the transmission signal is a spread-spectrum signal with a flat frequency response in the spectrum. In one embodiment, the transmitting antenna system 12 is used to transmit two transmission signals with different bandwidths generated by the transmitting circuit 11.

[0063] Figure 2A This is a component block diagram of a radar device 10-1 according to an embodiment of the present invention. Please refer to... Figure 2A The transmitting antenna system 12A of the radar device 10-1 includes a transmitting antenna TX1. The transmitting circuit 11 includes an amplifier PA. The amplifier PA is coupled to the transmitting antenna TX1.

[0064] In one embodiment, the operating frequency band of the transmitting antenna TX1 may be matched to the frequency bands of two transmitted signals with different bandwidths generated by the transmitting circuit 11. For example, it may be matched to the frequency bands of 10.5 to 10.55 GHz (corresponding to narrowband) and 7.5 to 8.5 GHz (corresponding to wideband). In one embodiment, the operating frequency band of the transmitting antenna TX1 should at least be matched to the narrower of the frequency bands of the two transmitted signals with different bandwidths generated by the transmitting circuit 11. For example, it only needs to have excellent matching effect for the 10.5 to 10.55 GHz (corresponding to narrowband) frequency band and acceptable matching effect for the 7.5 to 8.5 GHz (corresponding to wideband) frequency band.

[0065] In one embodiment, the antenna types operating in narrowband and broadband applications can be, but are not limited to, dipole, loop, patch, log-periodic dipole array (LPDA), spiral, dish, printed, or other types. Furthermore, the antennas of these types can be further parameterized to suit narrowband and broadband applications respectively.

[0066] In one embodiment, such as Figure 2A As shown, the radar device 10-1 further includes a matching circuit 121. The matching circuit 121 is coupled between the transmitting antenna TX1 and the transmitting circuit 11. The matching circuit 121 is used to achieve impedance matching between the transmitting antenna TX1 and the transmitting circuit 11. The matching circuit 121 may include microstrip lines, inductors, capacitors, or other electronic components. Furthermore, by configuring the matching circuit 121, the transmitting antenna TX1 can be operated within the desired frequency band. For example, the matching circuit 121 can be designed to have excellent matching performance for the 10.5 to 10.55 GHz band (corresponding to a narrow band), while having acceptable matching performance for the 7.5 to 8.5 GHz band (corresponding to a wide band).

[0067] It should be noted that the design of the transmitting antenna TX1 may vary in order to operate or be matched to a specific frequency band. Users can adjust the design of the transmitting antenna TX1 according to their actual needs.

[0068] Figure 2B This is a component block diagram of a radar device 10-2 according to another embodiment of the present invention. Please refer to... Figure 2B The transmitting antenna system 12B of the radar device 10-2 includes two transmitting antennas TX1 and TX2. The transmitting circuit 11 includes an amplifier PA. The amplifier PA is selectively connected to one of the two transmitting antennas TX1 and TX2.

[0069] In one embodiment, the distance λ between the transmitting antennas TX1 and TX2 D For λ HB / 2, and λ HB Let λ be the wavelength of the transmitted signal transmitted by transmitting antenna TX1 and the transmitted signal transmitted by transmitting antenna TX2, where λ is the higher center frequency. For example, if the center frequency of the transmitted signal transmitted by transmitting antenna TX1 is 8 GHz and the center frequency of the transmitted signal transmitted by transmitting antenna TX2 is 10 GHz, then the distance λ between transmitting antennas TX1 and TX2 is... DThe value is (8 x 10^8) / (10 x 10^9) = 8 x 10^-2 meters. In this embodiment, it is assumed that the center frequency of the transmission signal corresponding to the narrowband is higher and the center frequency of the transmission signal corresponding to the broadband is lower, but this is not a limitation.

[0070] In one embodiment, the two transmitting antennas TX1 and TX2 form an antenna array. In another embodiment, each transmitting antenna TX1 and TX2 may correspond to an antenna port.

[0071] In one embodiment, the operating frequency bands of the transmitting antennas TX1 and TX2 may be matched to the frequency bands of two transmitted signals with different bandwidths generated by the transmitting circuit 11. For example, they may be matched to the frequency bands of 10.5 to 10.55 GHz (corresponding to narrowband) and 7.5 to 8.5 GHz (corresponding to wideband). In one embodiment, the operating frequency bands of the transmitting antennas TX1 and TX2 must at least be matched to the narrower of the frequency bands of the two transmitted signals with different bandwidths generated by the transmitting circuit 11. For example, they need to have excellent matching effect for the 10.5 to 10.55 GHz (corresponding to narrowband) frequency band and acceptable matching effect for the 7.5 to 8.5 GHz (corresponding to wideband) frequency band.

[0072] In one embodiment, under the same detection mode, the bandwidth of the transmitted signal transmitted by the transmitting antenna TX1 is the same as the bandwidth of the transmitted signal transmitted by the transmitting antenna TX2.

[0073] The implementation method of the antenna can be referred to the foregoing description, and will not be repeated here.

[0074] In one embodiment, such as Figure 2B As shown, the radar device 10-2 further includes matching circuits 121 and 122. Matching circuit 121 is coupled between transmitting antenna TX1 and transmitting circuit 11. Matching circuit 121 is used to achieve impedance matching between transmitting antenna TX1 and transmitting circuit 11. Matching circuit 122 is coupled between transmitting antenna TX2 and transmitting circuit 11. Matching circuit 122 is used to achieve impedance matching between transmitting antenna TX2 and transmitting circuit 11.

[0075] Matching circuits 121 and 122 may include microstrip lines, inductors, capacitors, or other electronic components. Furthermore, by configuring matching circuits 121 and 122, transmitting antennas TX1 and TX2 can be operated within desired frequency bands, respectively. For example, matching circuits 121 and 122 can be designed to provide excellent matching for the 10.5 to 10.55 GHz band (corresponding to a narrowband) and acceptable matching for the 7.5 to 8.5 GHz band (corresponding to a wideband).

[0076] In one embodiment, the matching bandwidth of matching circuit 121 is the same as that of matching circuit 122.

[0077] In one embodiment, the transmitting antennas TX1 and TX2 have the same or substantially the same specifications, operating frequency bands, and / or dimensions.

[0078] It should be noted that the design of transmitting antennas TX1 and TX2 may vary in order to operate or be matched to a specific frequency band. Users can adjust the design of transmitting antennas TX1 and TX2 according to their actual needs.

[0079] Please refer to Figure 1 The receiving antenna system 13 is used to receive echo signals. The radar device 10 can transmit signals to external objects (e.g., people, vehicles, walls, or buildings) via the transmitting antenna system 12. Then, the radar device 10 can receive the echo signals reflected from the external objects via the receiving antenna system 13. The echo signal is generated by the reflection of the transmitted signal by the external object.

[0080] In one embodiment, the receiving antenna system 13 receives two echo signals with different bandwidths. For example, the first echo signal (one of the two echo signals) has a bandwidth of 50 MHz (i.e., corresponding to narrowband), and the second echo signal (one of the two echo signals) has a bandwidth greater than 500 MHz, for example, 1 GHz (i.e., corresponding to wideband). In another embodiment, the bandwidth of the first echo signal is less than the bandwidth of the second echo signal.

[0081] Please refer to Figure 2A and Figure 2B The receiving antenna system 13 of radar devices 10-1 and 10-2 includes two receiving antennas RX1 and RX2.

[0082] In one embodiment, the two receiving antennas RX1 and RX2 form an antenna array. In another embodiment, each receiving antenna RX1 and RX2 may correspond to one antenna port.

[0083] In one embodiment, the operating frequency bands of the two receiving antennas RX1 and RX2 are respectively matched to the frequency bands of two received signals with different bandwidths. For example, receiving antenna RX1 is matched to a frequency band of 10.5 to 10.55 GHz (corresponding to a narrow band), and receiving antenna RX2 is matched to a frequency band of 7.5 to 8.5 GHz (corresponding to a wide band).

[0084] In one embodiment, the bandwidth of the echo signal received by receiving antenna RX1 is smaller than the bandwidth of the echo signal received by receiving antenna RX2. For example, the frequency band of the echo signal received by receiving antenna RX1 is 10.5 to 10.55 GHz (corresponding to narrowband), and the frequency band of the echo signal received by receiving antenna RX2 is 7.5 to 8.5 GHz (corresponding to wideband).

[0085] The implementation method of the antenna can be referred to the foregoing description, and will not be repeated here.

[0086] In one embodiment, such as Figure 2A and Figure 2B As shown, the radar device 10-2 further includes matching circuits 131 and 132. Matching circuit 131 is coupled between receiving antenna RX1 and receiving circuit 14. Matching circuit 131 is used to achieve impedance matching between receiving antenna RX1 and receiving circuit 14. Matching circuit 132 is coupled between receiving antenna RX2 and receiving circuit 14. Matching circuit 132 is used to achieve impedance matching between receiving antenna RX2 and receiving circuit 14.

[0087] Matching circuits 131 and 132 may include microstrip lines, inductors, capacitors, or other electronic components. Furthermore, by configuring matching circuits 131 and 132, receiving antennas RX1 and RX2 can be operated within desired frequency bands, respectively. For example, matching circuit 131 may be designed to provide excellent matching for a frequency band of 10.5 to 10.55 GHz (corresponding to a narrowband), and matching circuit 132 may be designed to provide excellent matching for a frequency band of 7.5 to 8.5 GHz (corresponding to a wideband).

[0088] In one embodiment, the matching bandwidth of matching circuit 131 is less than the matching bandwidth of matching circuit 132. For example, the matching bandwidth of matching circuit 131 is 50MHz, and the matching bandwidth of matching circuit 132 is at least 500MHz.

[0089] In one embodiment, please refer to Figure 2A Since the transmitting antenna TX1 needs to transmit a first transmitted signal and a second transmitted signal with different bandwidths, and the matching circuit 121 needs to enable the transmitting antenna TX1 to operate in frequency bands with different bandwidths, but the receiving antenna RX1 only needs to receive, for example, a narrow-band first echo signal, and the matching circuit 131 only needs to enable the receiving antenna RX1 to operate in the frequency band of the first echo signal, the matching bandwidth of the matching circuit 121 is greater than that of the matching circuit 131. For example, the matching frequency band of the matching circuit 131 is 10.5 to 10.55 GHz, so the matching bandwidth of the matching circuit 131 is, for example, 50 MHz, and the matching bandwidth of the matching circuit 121 must be at least greater than the bandwidth range covered by 10.5 to 10.55 GHz, for example, greater than 50 MHz.

[0090] In one embodiment, please refer to Figure 2B Since the transmitting antenna TX1 needs to transmit a first transmitted signal and a second transmitted signal with different bandwidths, and the matching circuit 121 needs to enable the transmitting antenna TX1 to operate in frequency bands with different bandwidths, but the receiving antenna RX1 only needs to receive, for example, a narrow-band first echo signal, and the matching circuit 131 only needs to enable the receiving antenna RX1 to operate in the frequency band of the first echo signal, the matching bandwidth of the matching circuit 121 is greater than that of the matching circuit 131. For example, the matching frequency band of the matching circuit 131 is 10.5 to 10.55 GHz, so the matching bandwidth of the matching circuit 131 is, for example, 50 MHz, and the matching bandwidth of the matching circuit 121 must be at least greater than the bandwidth range covered by 10.5 to 10.55 GHz, for example, greater than 50 MHz. Furthermore, since the transmitting antenna TX2 needs to transmit a first transmitted signal and a second transmitted signal with different bandwidths, and the matching circuit 122 needs to enable the transmitting antenna TX2 to operate in frequency bands with different bandwidths, but the receiving antenna RX1 only needs to receive, for example, a narrow-band first echo signal, and the matching circuit 131 only needs to enable the receiving antenna RX1 to operate in the frequency band of the first echo signal, the matching bandwidth of the matching circuit 122 is greater than that of the matching circuit 131. For example, the matching frequency band of the matching circuit 131 is 10.5 to 10.55 GHz, so the matching bandwidth of the matching circuit 131 is, for example, 50 MHz, and the matching bandwidth of the matching circuit 122 must be at least greater than the bandwidth range covered by 10.5 to 10.55 GHz, for example, greater than 50 MHz.

[0091] In one embodiment, the size of the receiving antenna RX1 is smaller than the size of the receiving antenna RX2. Taking a patch antenna as an example, due to resonant modes, impedance matching, coupling structures, and / or other factors, the size of an antenna suitable for low-frequency signals will be larger than the size of an antenna suitable for high-frequency signals. In this embodiment, the narrowband first echo signal is, for example, a high-frequency signal, and the wideband second echo signal is, for example, a low-frequency signal. Therefore, in this embodiment, assuming that the receiving antenna RX1 for receiving the first echo signal is designed for narrowband and the receiving antenna RX2 for receiving the second echo signal is designed for wideband, the size of the receiving antenna RX1 is smaller than the size of the receiving antenna RX2. However, in other embodiments, it is also possible that the narrowband first echo signal is, for example, a low-frequency signal, and the wideband second echo signal is, for example, a high-frequency signal. In this case, the receiving antenna RX1 for receiving the first echo signal is designed for narrowband, and the receiving antenna RX2 for receiving the second echo signal is designed for wideband, in which case the size of the receiving antenna RX1 is larger than the size of the receiving antenna RX2.

[0092] However, the size of antennas suitable for low-frequency signals can be reduced through multimode, parasitic, slotted structures, or other techniques. Therefore, the size comparison of receiving antennas RX1 and RX2 is not limited to the embodiments described above.

[0093] Please refer to Figure 1 The receiving circuit 14 is used to generate an internal signal based on the radio frequency signal and the first signal. The two echo signals with different bandwidths received by the two receiving antennas RX1 and RX2 can form a radio frequency signal, which will be described in detail later. The description of the first signal can be found in the foregoing explanation and will not be repeated here.

[0094] Control circuit 15 is coupled to transmitting circuit 11. Control circuit 15 is used to generate one or more control signals. These control signals change according to the period of a first signal. For example, the control signal can be set to a second signal or a third signal, and the difference between these two signals lies in voltage, current, and / or digital encoding. The first signal is a periodic chirp signal. The period of a combination of one or more chirp signals can be used as the period of the first signal. During a certain period of the first signal, the control signal is the second signal (e.g., a high-level signal, see reference). Figure 4A The control signal RX SW in the first signal is coded as "2"; in the other cycle of the first signal, the control signal is the third signal (e.g., low level, see reference). Figure 4A (The control signal RX SW in the example is encoded as "1"). Therefore, the control signal will be different in different periods of the first signal. It should be noted that the voltage, current, and / or digital encoding of the control signal can be changed according to actual needs. In addition, the switching or changing time point of the control signal may be, for example, at the boundary between two periods of the first signal, which will be detailed in subsequent embodiments.

[0095] Selection circuit 16 is coupled to transmitting circuit 11, transmitting antenna system 12, receiving antenna system 13, receiving circuit 14 and control circuit 15.

[0096] In one embodiment, the selection circuit 16 is used to selectively connect one of a plurality of receiving antennas. Figure 2A and Figure 2B For example, the selection circuit 16 of radar devices 10-1 and 10-2 includes a switching circuit 161. The switching circuit 161 can be composed of one or more electrical components such as multiplexers and switches; this embodiment of the invention is not limited to this. The receiving circuit 14 further includes a low-noise amplifier (LNA). The LNA is coupled to the output of the switching circuit 161.

[0097] Please refer to Figure 2A and Figure 2B Matching circuit 131 is coupled between switching circuit 161 of selection circuit 16 and receiving antenna RX1, and matching circuit 132 is coupled between switching circuit 161 of selection circuit 16 and receiving antenna RX2.

[0098] In one embodiment, the switching circuit 161 can switch between the two receiving antennas RX1 and RX2 to transmit the echo signals received by the two receiving antennas RX1 and RX2 to the receiving circuit 14.

[0099] In one embodiment, selection circuit 16 is used to selectively connect one of a plurality of transmitting antennas. Figure 2B For example, the selection circuit 16 of the radar device 10-2 further includes a switching circuit 162. The switching circuit 162 can be composed of one or more electrical components such as multiplexers and switches, and this embodiment of the invention is not limited thereto. The matching circuit 121 is coupled between the switching circuit 162 of the selection circuit 16 and the transmitting antenna TX1, and the matching circuit 122 is coupled between the switching circuit 162 of the selection circuit 16 and the transmitting antenna TX2.

[0100] In one embodiment, the switching circuit 162 can switch between two transmitting antennas TX1 and TX2 to transmit the transmission signal generated by the transmitting circuit 11 to either transmitting antenna TX1 or transmitting antenna TX2.

[0101] In one embodiment, the selection circuit 16 may also achieve selective connection by disabling unused transmitting antennas in transmitting antennas TX1 and TX2, and / or by disabling unused receiving antennas in receiving antennas RX1 and RX2.

[0102] It should be noted that, Figure 2A In this embodiment, since the transmitting antenna system 12A includes a transmitting antenna TX1, and the transmitting circuit 11 generates one of two transmission signals based on one or more control signals provided by the control circuit 15, and then the transmitting antenna TX1 transmits one of the two transmission signals. Therefore, in Figure 2A In this embodiment, the selection of a transmitting antenna is not required. Figure 2A The transmitting antenna system 12A in the embodiment may be uncoupled from the selection circuit 16.

[0103] The following combinations Figure 3A and Figure 3B To explain in more detail the hardware structure of radar device 10.

[0104] Figure 3A This is a component module diagram of a radar device 10-3 according to an embodiment of the present invention. Please refer to... Figure 3AThe radar device 10-3 includes (but is not limited to) a transmitting circuit 11, a transmitting antenna system 12, a receiving antenna system 13, a receiving circuit 14, a control circuit 15, and a selection circuit 16. Furthermore, the radar device 10-3 may further include (but is not limited to) a frequency synthesizer 171, a modulator 18, a clock generator 19, and a processing unit 20.

[0105] The transmitting circuit 11 includes an amplifier PA and a mixer TXMIX. The amplifier PA is coupled to the mixer TXMIX. The amplifier PA is used to amplify the signal (e.g., the output signal of the mixer TXMIX). The mixer TXMIX is used to mix the signal to generate the transmitted signal. In addition, the transmitting circuit 11 may also include (but is not limited to) a filter LPF and a digital-to-analog converter DAC.

[0106] For a description of the transmitting antenna system 12, please refer to [link / reference]. Figure 1 The transmitting antenna system 12 and Figure 2B For a description of the transmitting antenna system 12B and an introduction to the receiving antenna system 13, please refer to [the relevant documentation]. Figure 1 , Figure 2A and Figure 2B The description of the receiving antenna system 13 will not be repeated here.

[0107] The receiving circuit 14 includes a low-noise amplifier (LNA) and a mixer (RXMIX). The LNA is coupled to the mixer (RXMIX). The LNA amplifies the signal (e.g., the echo signal). The mixer (RXMIX) mixes the signal (e.g., the output signal of the LNA) to generate an intermediate frequency (IF) signal. Additionally, the receiving circuit 14 may also include (but is not limited to) an intermediate frequency amplifier (IFA) and an analog-to-digital converter (ADC).

[0108] For a description of the control circuit 15 and the selection circuit 16, please refer to [link / reference]. Figure 1 , Figure 2A and Figure 2B The explanation will not be repeated here.

[0109] In this embodiment, the control circuit 15 is further coupled to the amplifier PA. In one embodiment, the amplifier PA sets its output power according to one or more control signals generated by the control circuit 15.

[0110] Frequency synthesizer 171 is coupled to transmitting circuit 11 and receiving circuit 14. In one embodiment, control circuit 15 is coupled to transmitting circuit 11 via frequency synthesizer 171. In another embodiment, control circuit 15 is directly connected to transmitting circuit 11. Frequency synthesizer 171 is used to generate a first signal and provide the first signal to transmitting circuit 11, receiving circuit 14, and control circuit 15. In this case, the first signal is a continuous wave signal.

[0111] Modulator 18 can be implemented by an N-order (N is a positive integer greater than zero) oversampling modulator or an N-bit Nyquist frequency sampler.

[0112] A clock generator 19 is coupled to a frequency synthesizer 171, a modulator 18, and an analog-to-digital converter (ADC). The clock generator 19 generates a clock signal (or a local oscillation signal). The frequency synthesizer 171 generates a first signal with a period based on the clock signal. The control circuit 15 synchronizes the first signal based on the clock signal. Furthermore, the synchronization of the first signal can be considered as the period of one or more control signals remaining constant and the period of the first signal having a fixed overlap range. For example, the switching or changing period of the control signal can be the same as the period of the first signal; or, the switching or changing time of the control signal can be synchronized with the start or end point of the period of the first signal by shifting forward or backward by a predetermined time; or, the switching or changing time of the control signal can be synchronized with the start or end point of the period of the first signal.

[0113] Modulator 18 oversamples and modulates the clock signal to generate a sine-like digital signal, and drives a digital-to-analog converter (DAC) to generate an analog sine wave signal. Then, filter LPF performs low-pass filtering on the analog sine wave signal to form the sine wave signal input to mixer TXMIX. Mixer TXMIX mixes (e.g., up-converts) the sine wave signal based on a first signal (e.g., a continuous wave signal) from frequency synthesizer 171 to form the transmission signal.

[0114] The transmitted signal will be emitted through the transmitting antenna in the transmitting antenna system 12. Figure 2A In this regard, the transmitting antenna TX1 transmits the signal. Figure 2B In other words, the transmitted signal will be transmitted through the transmitting antenna TX1 or TX2 that is turned on / off by the switching circuit 162.

[0115] On the other hand, the echo signal is received by the receiving antenna system 13. Figure 2A and Figure 2BThe echo signal is received by the receiving antenna RX1 or RX2, which is turned on / off by the switching circuit 161. The low-noise amplifier (LNA) amplifies the echo signal received by the receiving antenna RX1 or RX2, and the mixer RXIMX mixes (e.g., down-converts) the amplified signal according to the first signal (e.g., a continuous wave signal) generated by the frequency synthesizer 171 to generate an intermediate frequency signal.

[0116] The intermediate frequency (IF) amplifier circuit includes an IF amplifier IFA-1, a correction circuit IFA-2 (optional), and a filter IFA-3. The IF amplifier IFA-1 filters and amplifies the IF signal to a specific frequency band, then filters the signal to the desired frequency band via the filter, and converts it into a baseband signal DO (e.g., a baseband digital signal) via an analog-to-digital converter (ADC). The correction circuit IFA-2 can be a summing circuit that sums the IF signal with an inverted sine wave signal (i.e., subtracts the analog sine wave signal generated by the DAC from the IF signal). The correction circuit IFA-2 can correct for flicker noise, DC offset, local oscillator leakage, and other problems encountered by the echo signal based on the sine wave signal. In other embodiments, the location of the correction circuit IFA-2 may differ. For example, it can be located before the intermediate frequency amplifier IFA-1 (i.e., coupled between the mixer RXIIX and the intermediate frequency amplifier IFA-1), or after the filter IFA-3 (i.e., coupled between the filter IFA-3 and the analog-to-digital converter ADC).

[0117] The processing unit 20 is coupled to the receiving circuit 14. (See also...) Figure 3A and with Figure 2A and Figure 2B For example, the arithmetic processor 20 is coupled to the analog-to-digital converter (ADC) in the receiving circuit 14 and receives the baseband signal DO. The arithmetic processor 20 can be a chip, processor, microcontroller, application-specific integrated circuit (ASIC), or any type of digital circuit.

[0118] Figure 3B This is a component block diagram of a radar device 10-4 according to another embodiment of the present invention. Please refer to... Figure 3B The radar device 10-4 includes (but is not limited to) a transmitting circuit 11, a transmitting antenna system 12, a receiving antenna system 13, a receiving circuit 14, a control circuit 15, and a selection circuit 16. Furthermore, the radar device 10-4 may further include (but is not limited to) a pulse generator 172, a modulator 18, a clock generator 19, and a processing unit 20.

[0119] Figure 3B For descriptions of the transmitting circuit 11, transmitting antenna system 12, receiving antenna system 13, receiving circuit 14, selection controller 15, selection circuit 16, modulator 18, clock generator 19, filter LPF, digital-to-analog converter DAC, intermediate frequency amplifier circuit IFA, and analog-to-digital converter ADC, please refer to [the provided text]. Figure 3A The explanations of the same symbols will not be repeated here.

[0120] In this embodiment, pulse generator 172 is coupled to transmitting circuit 11 and receiving circuit 14. Pulse generator 172 generates a first signal and provides the first signal to transmitting circuit 11, receiving circuit 14, and control circuit 15. The first signal is a pulse signal. In one embodiment, control circuit 15 is coupled to transmitting circuit 11 via pulse generator 172. In another embodiment, selection controller 15 is directly connected to transmitting circuit 11, and transmitting circuit 11 can generate a pulse signal by enabling and disabling the signal output. In this embodiment, clock generator 19 is coupled to pulse generator 172, modulator 18, and analog-to-digital converter (ADC). Clock generator 19 generates a clock signal (or local oscillation signal). Pulse generator 172 generates a periodic first signal based on the clock signal. Selection controller 15 synchronizes the first signal based on the clock signal. Furthermore, the above-mentioned situation of synchronizing the first signal can be regarded as the control signal remaining unchanged for a fixed period of time and the period of the first signal having a fixed overlap range. For example, the switching or changing period of the control signal can be the same as the period of the first signal, or the switching or changing time point of the control signal can be synchronized with the start or end point of the period of the first signal by shifting forward or backward by a predetermined time, or the switching or changing time point of the control signal can be synchronized with the start or end point of the period of the first signal.

[0121] Radar devices 10, 10-1 to 10-4 can transmit signals to an external object O (also known as a target) via transmitting antenna system 12. Receiving antenna system 13 receives the echo signal reflected from the external object O. For example, transmitting antenna TX1 or TX2 transmits a continuous wave signal (corresponding to one or more cycles) or a pulse signal. Based on the fundamental frequency signal of receiving antenna RX1, the distance to the external object (corresponding to the position of the external object) can be determined.

[0122] In one embodiment, a signal frame time includes multiple transmit / receive cycles, which correspond to the cycles of the first signal and / or the transmitted signal.

[0123] For example, Figure 4A This is a schematic diagram of signal and antenna switching according to an embodiment of the present invention. Please refer to... Figure 4AThe first signal is, for example, a continuous wave signal, represented as a chirped signal (frequency changing over time). In this embodiment, the period of the first signal is, for example, the frequency variation period of the first signal. The continuous wave signal mixes with the sine wave signal to form the transmission signal. In one example, the first signal FS1 is presented as a triangular wave with frequency variation. Within one sweep cycle of the triangular wave, its frequency increases / rises with time in the rising phase and decreases / falls with time in the falling phase. The frequency of the first signal FS1 may be between frequency f1 and frequency f2. Alternatively, in another example, the first signal FS2 is presented as a sawtooth wave with frequency variation. Within one sweep cycle of the sawtooth wave, its frequency increases / rises with time in the rising phase and falls directly to the trough in the falling phase. The frequency of the first signal FS2 may be between frequency f1 and frequency f2. In this embodiment, a signal frame time includes, for example, two transmit / receive cycles. Each transmit / receive cycle may include, for example, two cycles of the first signal FS1 (or the first signal FS3), or four cycles of the first signal FS2 (or the first signal FS4). That is, each transmit / receive cycle is, for example, two sweep cycles of a triangular wave or four sweep cycles of a sawtooth wave. Thus, a signal frame time may, for example, consist of two cycles of the first signal FS1 plus two cycles of the first signal FS3, or a signal frame time may, for example, consist of four cycles of the first signal FS2 plus four cycles of the first signal FS4. However, the ratio of transmit / receive cycles to sweep cycles may vary in other ways.

[0124] Furthermore, the transmitting circuit 11 can also generate transmission signals of different bandwidths corresponding to the first signal with different bandwidths. In one example, the first signal FS3 is presented as a triangular wave with frequency variations. The frequency of the first signal FS3 can be between frequency f3 and frequency f4. The frequency band range of frequency f3 to frequency f4 is larger than the frequency band range of frequency f1 to frequency f2. Alternatively, in another example, the first signal FS4 is presented as a sawtooth wave with frequency variations.

[0125] In one embodiment, please refer to Figure 2A The transmitting antenna TX1 transmits a signal in each transmit / receive cycle within the signal frame time. Figure 4A For example, the control signal TX SW for the transmit antenna TX1 is encoded as "1", indicating that only the transmit antenna TX1 is turned on / selected / used (the transmitted signal is only transmitted via the transmit antenna TX1). It should be noted that since the transmit antenna TX1 is used only for multiple signal frames, the control signal TX SW may be ignored.

[0126] In one embodiment, please refer to Figure 2AThe transmitting circuit 11 is configured to select, based on one or more control signals, to generate only one of two transmitted signals with different bandwidths in each transmit / receive cycle during the signal frame time, such that the transmitting antenna TX1 selects to transmit only one of the two transmitted signals with different bandwidths in each transmit / receive cycle during the signal frame time. That is, in one transmit / receive cycle, the transmitting circuit 11 generates only a transmitted signal corresponding to one bandwidth, and the transmitting antenna TX1 transmits this transmitted signal; in another transmit / receive cycle, the transmitting circuit 11 generates only a transmitted signal corresponding to the other bandwidth, and the transmitting antenna TX1 transmits this transmitted signal.

[0127] In one embodiment, reference Figure 4A Taking the first signals FS1 and FS3 of the triangular wave as an example, in the first transmit / receive cycle (corresponding to the two cycles of the first signal FS1), the transmitting circuit 11 generates the first signal FS1 corresponding to the frequency between f1 and f2. Figure 4A The first transmission signal (e.g., the first transmission signal) is transmitted from the leftmost group of the first column (counting from the left in the first column). In the second transmit / receive cycle (corresponding to two cycles of the first signal FS3), the transmitting circuit 11 generates the first signal FS3 (corresponding to a frequency between f3 and f4)... Figure 4A The transmitted signal (e.g., the second transmitted signal) is the triangular wave from the left of the third column in the middle (counting from the left of the first group). In this embodiment, it can be considered that the transmitting circuit 11 generates two transmitted signals with different bandwidths corresponding to the first signal FS1 or FS3, controlled by the control signal TX SW. Furthermore, during these transmit and receive cycles, these two transmitted signals are transmitted at different times through the transmitting antenna TX1.

[0128] In another embodiment, it may be adopted Figure 4A Taking the first signals FS2 and FS4 of the sawtooth wave shown as an example, in the first transmit / receive cycle (corresponding to the four cycles of the first signal FS2), the transmitting circuit 11 generates the first signal FS2 corresponding to the frequency between f1 and f2 (corresponding to the frequency between f1 and f2). Figure 4A The transmission signal (e.g., the first transmission signal) is the sawtooth wave from the left of the second column in the middle. In the second transmit / receive cycle (corresponding to four cycles of the first signal FS4), the transmitting circuit 11 generates the first signal FS4 corresponding to the frequency between frequency f3 and frequency f4. Figure 4A The transmitted signal (e.g., the second transmitted signal) is the sawtooth wave from the left of the fourth column in the first group. In this embodiment, it can be considered that the transmitting circuit 11 generates two transmitted signals with different bandwidths corresponding to the first signal FS2 or FS4, controlled by the control signal TX SW. Furthermore, during these transmit and receive cycles, these two transmitted signals are transmitted at different times via the transmitting antenna TX1.

[0129] In one embodiment, please refer to Figure 2AThe selection circuit 16 (e.g., via switching circuit 161) is used to select only the receiving antenna RX1 to receive the first echo signal, or only the receiving antenna RX2 to receive the second echo signal, in each transmit / receive cycle during the signal frame time, based on one or more control signals. That is, the switching circuit 161 of the selection circuit 16 only turns on / selects / uses one receiving antenna (i.e., selects receiving antenna RX1 or RX2), thus interrupting the signals transmitted to the receiving circuit 14 by other receiving antennas.

[0130] by Figure 4A For example, the control signal RX SW used for receiving antennas RX1 and RX2 is encoded as "1" to indicate that only receiving antenna RX1 is turned on / selected / used (only the echo signal through receiving antenna RX1 is received by receiving circuit 14 and the echo signal transmitted from receiving antenna RX2 to receiving circuit 14 is interrupted), and is encoded as "2" to indicate that only receiving antenna RX2 is turned on / selected / used (only the echo signal through receiving antenna RX2 is received by receiving circuit 14 and the echo signal transmitted from receiving antenna RX1 to receiving circuit 14 is interrupted).

[0131] In one embodiment, reference Figure 4A Taking the echo signals corresponding to the first triangular wave signals FS1 and FS3 as an example, in the first transmit / receive cycle, the receiving antenna RX1 receives the echo signal corresponding to the first signal FS1 (e.g., the first echo signal). In the second transmit / receive cycle, the receiving antenna RX2 receives the echo signal corresponding to the first signal FS3 (e.g., the second echo signal). In this embodiment, the selection of the receiving antenna RX1 or RX2 can be considered as controlled by the control signal RX SW. However, in other embodiments, the same control signal may be used to control the selection of the transmission signal corresponding to the first signal FS1 or FS3 and the selection of the receiving antenna RX1 or RX2.

[0132] In another embodiment, a method corresponding to Figure 4A Taking the echo signals of the sawtooth wave first signals FS2 and FS4 as an example, in the first transmit / receive cycle, the receiving antenna RX1 receives the echo signal corresponding to the first signal FS2 (e.g., the first echo signal). In the second transmit / receive cycle, the receiving antenna RX2 receives the echo signal corresponding to the first signal FS4 (e.g., the second echo signal). In this embodiment, the selection of receiving antenna RX1 or RX2 can be considered as controlled by the control signal RX SW. However, in other embodiments, the same control signal may be used to control the selection of the transmission signal corresponding to the first signal FS2 or FS4 and the selection of receiving antenna RX1 or RX2.

[0133] In one embodiment, the transmit antenna TX1 and the receive antenna (receive antenna RX1 or RX2) that are turned on / selected / used in a transmit / receive cycle form a transmit / receive pairing.

[0134] "TX1+RX1" represents the transmit / receive combination TRC of transmit antenna TX1 and receive antenna RX1; "TX1+RX2" represents the transmit / receive combination TRC of transmit antenna TX1 and receive antenna RX2.

[0135] Furthermore, the duration of the signal corresponding to any code (e.g., "1" or "2") of the control signals TX SW and RX SW corresponds to the period of the first signal or the transmitted signal. For example, the two codes correspond to a first signal FS1 of a triangular wave or a first signal FS2 of a sawtooth wave. The switching time between two adjacent codes of the control signal RX SW is, for example, located at the beginning, end, or end point of the period of the first signals FS1 and FS2, or the switching time between two adjacent codes of the control signal RX SW may also be located at the beginning, end, or end point of the period of the first signals FS1 and FS2 shifted forward or backward by a predetermined time. Figure 2A or Figure 2B As shown, the transmission signal is generated based on the control signal. See also... Figure 3A and Figure 3B The control signal is generated based on a first signal generated by the frequency synthesizer 171 or the pulse generator 172, and the first signal is generated based on a clock signal provided by the clock generator 19. Therefore, the switching time and period of the control signal can be synchronized with the first signal and the transmission signal.

[0136] In one embodiment, a first transmitted signal and a corresponding first echo signal generated by its reflection are used in a first detection mode, and a second transmitted signal with a different bandwidth and a corresponding second echo signal generated by its reflection are used in a second detection mode. Furthermore, the detection power of the first detection mode is greater than the detection power of the second detection mode. Detection power, also known as radar transmit power, refers to the power of electromagnetic waves emitted by radar devices 10, 10-1 to 10-4. Detection power may affect the detection range, range resolution, and / or anti-interference capability of radar devices 10, 10-1 to 10-4. As described above, the transmitting circuit 11 can generate two transmitted signals with different bandwidths. In one embodiment, the detection power used for the first transmitted signal with a smaller bandwidth is greater than the detection power used for the second transmitted signal with a larger bandwidth.

[0137] In one embodiment, radar devices 10, 10-1 to 10-4 are configured to select only one of two detection modes in each transceiver cycle during the signal frame time, based on one or more control signals. That is, in one transceiver cycle, only the first detection mode is selected to be executed, and in another transceiver cycle, only the second detection mode is selected to be executed. For example, in one transceiver cycle, only a first transmission signal with a smaller bandwidth is selected to be transmitted to execute the first detection mode, and in another transceiver cycle, only a second transmission signal with a larger bandwidth is selected to be transmitted to execute the second detection mode.

[0138] by Figure 4A For example, in the first transmit / receive cycle, a first detection mode corresponding to the first transmitted signal (corresponding to the first signal FS1 or FS2 with a bandwidth of frequency f1 to frequency f2) is executed; in the second transmit / receive cycle, a second detection mode corresponding to the second transmitted signal (corresponding to the first signal FS3 or FS4 with a bandwidth of frequency f3 to frequency f4) is executed.

[0139] In one embodiment, please refer to Figure 2A , Figure 2B , Figure 3A and Figure 3B The amplifier PA is used to output different powers in two detection modes based on one or more control signals. The output power of the amplifier PA is related to the detection power. The higher the output power of the amplifier PA, the higher the detection power; the lower the output power of the amplifier PA, the lower the detection power. In one embodiment, the amplifier PA provides more power to a first transmission signal with a smaller bandwidth than it provides to a second transmission signal with a larger bandwidth.

[0140] by Figure 4A For example, in the first transmit / receive cycle, the transmitting circuit 11 generates a first transmit signal corresponding to a first signal FS1 or a first signal FS2 between frequencies f1 and f2, wherein the amplifier PA outputs a larger power. In the second transmit / receive cycle, the transmitting circuit 11 generates a second transmit signal corresponding to a first signal FS3 or a first signal FS4 between frequencies f3 and f4, wherein the amplifier PA outputs a smaller power.

[0141] It should be noted that the output power may still be adjusted due to antenna gain, mismatch, or other factors. For example, for narrowband applications, the output load can be close to 50 ohms. However, for broadband applications, lower gain and mismatch require a higher output power to compensate for the losses.

[0142] In one embodiment, please refer to Figure 2AThe receiving circuit 14 includes a low-noise amplifier (LNA) that amplifies the two echo signals received by the receiving antennas RX1 and RX2. Furthermore, the LNA provides corresponding gain and / or impedance matching based on the bandwidth of the echo signals.

[0143] In one embodiment, the range resolution of the first detection mode is, for example, smaller than the range resolution of the second detection mode. Range resolution is the ability of a radar system to distinguish multiple targets approaching along a radial distance. Range resolution depends primarily on the bandwidth of the transmitted signal. A wider bandwidth results in higher range resolution. Figure 4A For example, the distance resolution of the first detection mode (corresponding to the bandwidth of frequency f1 to frequency f2) using the first transmission signal with a smaller bandwidth is smaller than the distance resolution of the second detection mode (corresponding to the bandwidth of frequency f3 to frequency f4) using the second transmission signal with a larger bandwidth.

[0144] Please refer to Figure 3A and Figure 3B The receiving circuit 14 generates an internal signal (e.g., the aforementioned baseband signal DO) based on the radio frequency signal and a first signal generated by the frequency synthesizer 171 or pulse generator 172. This internal signal includes multiple internal sub-signals formed corresponding to multiple transmit / receive cycles of the signal frame time. Figure 4A For example, assuming the signal frame includes two transmit and receive cycles, the receiving circuit 14 can generate a first internal signal corresponding to the first transmit and receive cycle, and the receiving circuit 14 can generate a second internal signal corresponding to the second transmit and receive cycle.

[0145] Furthermore, the processing processor 20 uses these internal sub-signals to determine the spatial information of external objects. For a signal frame comprising two transmit / receive cycles, the processing processor 20 can determine the spatial information of external objects based on the first internal signal and the second internal signal.

[0146] In one embodiment, the spatial information of the external object includes distance information. The processing processor 20 can obtain the spectral information of the fundamental frequency signal DO corresponding to different internal signals through Fast Fourier Transform, Discrete Fourier Transform (DFT), or other time-domain to frequency-domain transformations. The amplitude of the spectral information corresponds to the distance information. Taking a power spectrum diagram as an example, assuming the echo signal is obtained through reflection from an external object, each internal signal will have a peak at the location of this external object (or its distance from this external object). If any peak value corresponding to a distance is greater than an amplitude threshold, it is determined that an external object exists, and the distance information is determined accordingly.

[0147] Figure 4B This is a schematic diagram of one-dimensional detection according to an embodiment of the present invention. Please refer to... Figure 2A ,Figure 4A and Figure 4B ,exist Figure 2A The structure (e.g., one transmitting antenna TX1 and two receiving antennas RX1, RX2) and operation in Figure 4A The distance information can be determined by switching the transmit / receive combination TRC shown. However, this embodiment assumes that the detection field of view is [missing information]. Figure 4B The 180 degrees shown did not yield angle information. Angle information could be the direction or angle of an external object relative to the radar device 10-1.

[0148] Figure 5 This is a schematic diagram of the angle of arrival θ according to another embodiment of the present invention. Please refer to... Figure 5 Radar devices 10, 10-2 to 10-4 can transmit signals to an external object O (also known as a target) via transmitting antenna system 12. Transmitting antennas TX1, TX2, and receiving antennas RX1 and RX2 are arranged in a row in space along the same direction (e.g., horizontally in the diagram), and the distance d2 between transmitting antennas TX1 and TX2 is the aforementioned distance λ. D (For example, half the wavelength of a transmission signal with a smaller bandwidth, i.e., the aforementioned λ) HB / 2). Therefore, the distances from transmitting antenna TX1 and transmitting antenna TX2 to the external object O differ by d2sinθ. The angle of arrival θ is the angle of the external object O relative to the radar device 10, 10-2 to 10-4 (which can be used as angle information). R is the distance between the external object O and transmitting antenna TX1 (which can be used as distance information).

[0149] In one embodiment, the processing processor 20 can convert multiple echo signals into spatial spectrum information to determine angle information. A peak in the spatial spectrum information corresponds to the angle information, and the spatial information includes the angle information. The azimuth information is, for example, the angle of arrival θ described above.

[0150] Angle of Arrival (AoA) estimation algorithms include, for example, the Multiple Signal Classification Algorithm (MUSIC), the Root-MUSIC algorithm, or the Estimation of Signal Parameters via Rotational Invariance Techniques (ESPRIT) algorithm.

[0151] Figure 6A This is a schematic diagram of signal and antenna switching according to another embodiment of the present invention. Please refer to... Figure 6AFor an introduction to the first signals FS1 to FS4, please refer to [link / reference]. Figure 4A The explanation will not be repeated here. It should also be noted that... Figure 6A In this embodiment, a signal frame time includes, for example, four transmit / receive cycles. Each transmit / receive cycle may include, for example, one cycle of the first signal FS1 (or the first signal FS3), or two cycles of the first signal FS2 (or the first signal FS4). That is, each transmit / receive cycle is, for example, one sweep cycle of a triangular wave or two sweep cycles of a sawtooth wave. Thus, a signal frame time may include, for example, two cycles of the first signal FS1 plus two cycles of the first signal FS3, or, for example, four cycles of the first signal FS2 plus four cycles of the first signal FS4. However, the ratio of transmit / receive cycles to sweep cycles may also vary.

[0152] Furthermore, the control signal TX SW used for transmitting antennas TX1 and TX2 is encoded as "1" to indicate that transmitting antenna TX1 is only turned on / selected / used (the transmission signal is only transmitted through transmitting antenna TX1 and the transmission signal transmitted from transmitting circuit 11 to transmitting antenna TX2 is interrupted), and is encoded as "2" to indicate that transmitting antenna TX2 is only turned on / selected / used (the transmission signal is only transmitted through transmitting antenna TX2 and the transmission signal transmitted from transmitting circuit 11 to transmitting antenna TX1 is interrupted).

[0153] On the other hand, the control signal RX SW used for receiving antennas RX1 and RX2 is encoded as "1" to indicate that only receiving antenna RX1 is turned on / selected / used (only the echo signal of receiving antenna RX1 is received by receiving circuit 14 and the echo signal of receiving antenna RX2 transmitted to receiving circuit 14 is interrupted), and is encoded as "2" to indicate that only receiving antenna RX2 is turned on / selected / used (only the echo signal of receiving antenna RX2 is received by receiving circuit 14 and the echo signal of receiving antenna RX1 transmitted to receiving circuit 14 is interrupted).

[0154] In one embodiment, please refer to Figure 2BThe selection circuit 16 (e.g., via switching circuit 162) is used, based on one or more control signals, to select only the transmit antenna TX1 to transmit either the first or second transmit signal, or only the transmit antenna TX2 to transmit either the first or second transmit signal, in each transmit / receive cycle during the signal frame time. Furthermore, in the first detection mode, within one transmit / receive cycle, the transmit circuit 11 generates only the first transmit signal corresponding to one bandwidth, and the transmit antenna TX1 transmits the first transmit signal; in another transmit / receive cycle, the transmit circuit 11 also generates the first transmit signal, and the transmit antenna TX2 transmits the first transmit signal. In the second detection mode, within one transmit / receive cycle, the transmit circuit 11 generates only the second transmit signal corresponding to another bandwidth, and the transmit antenna TX1 transmits the second transmit signal; in another transmit / receive cycle, the transmit circuit 11 also generates the second transmit signal, and the transmit antenna TX2 transmits the second transmit signal. Furthermore, the first detection mode and the second detection mode can be executed alternately. That is, in this embodiment, for example, there may be four transmit and receive cycles, each of which performs the actions of "transmitting a first transmission signal with transmitting antenna TX1", "transmitting a first transmission signal with transmitting antenna TX2", "transmitting a second transmission signal with transmitting antenna TX1", and "transmitting a second transmission signal with transmitting antenna TX2".

[0155] In one embodiment, reference Figure 6A Taking the first signals FS1 and FS3 of the triangular wave as an example, in the first and second transmit / receive cycles (corresponding to the two cycles of the first signal FS1), the transmitting circuit 11 generates the first signal FS1 corresponding to a frequency between f1 and f2. Figure 6A The first transmit signal (e.g., the first transmitted signal) is generated from the leftmost triangular wave in the first column of the first transmission circuit (corresponding to the first cycle of the first signal FS1). In the first transmit cycle (corresponding to the first cycle of the first signal FS1), the first transmitted signal is transmitted by the transmitting antenna TX1, and in the second transmit cycle (corresponding to the second cycle of the first signal FS1), the first transmitted signal is transmitted by the transmitting antenna TX2. In the third and fourth transmit cycles (corresponding to the two cycles of the first signal FS3), the transmitting circuit 11 generates the first signal FS3 (corresponding to the frequency between f3 and f4). Figure 6AThe transmission signal (e.g., the second transmission signal) of the first group (counting from the left in the third column) is transmitted by the transmitting antenna TX1 during the third transmit / receive cycle (corresponding to the first cycle of the first signal FS3), and by the transmitting antenna TX2 during the fourth transmit / receive cycle (corresponding to the second cycle of the first signal FS3). In this embodiment, it can be considered that the transmitting circuit 11 generates two transmission signals with different bandwidths corresponding to the first signal FS1 or FS3 by the control signal TXSW, and controls the selection of the transmitting antenna TX1 or the transmitting antenna TX2 to transmit one of the two transmission signals.

[0156] In another embodiment, it may be adopted Figure 6A Taking the first signals FS2 and FS4 of the sawtooth wave shown as an example, in the first and second transmit / receive cycles (corresponding to the four cycles of the first signal FS2), the transmitting circuit 11 generates the first signal FS2 corresponding to the frequency between f1 and f2. Figure 6A The transmission signal (e.g., the first transmission signal) of the first group of sawtooth waves (counting from the left in the second column) is transmitted by the transmitting antenna TX1 during the first transmit / receive cycle (corresponding to the first and second cycles of the first signal FS1), and by the transmitting antenna TX2 during the second transmit / receive cycle (corresponding to the third and fourth cycles of the first signal FS1). During the third and fourth transmit / receive cycles (corresponding to the four cycles of the first signal FS4), the transmitting circuit 11 generates the first signal FS4 (corresponding to the frequency between f3 and f4)... Figure 6A The transmission signal (e.g., the second transmission signal) of the first group (the sawtooth wave from the left of the fourth column) is transmitted by the transmitting antenna TX1 during the third transmit / receive cycle (corresponding to the first and second cycles of the first signal FS4), and by the transmitting antenna TX2 during the fourth transmit / receive cycle (corresponding to the third and fourth cycles of the first signal FS4). In this embodiment, it can be considered that the transmitting circuit 11 generates two transmission signals with different bandwidths corresponding to the first signal FS2 or FS4 by the control signal TX SW, and controls the selection of the transmitting antenna TX1 or the transmitting antenna TX2 to transmit one of the two transmission signals.

[0157] In one embodiment, please refer to Figure 2B The selection circuit 16 (e.g., via switching circuit 161) is used to select only the receiving antenna RX1 to receive the first echo signal, or only the receiving antenna RX2 to receive the second echo signal, in each transmit / receive cycle during the signal frame time, based on one or more control signals. That is, the switching circuit 161 of the selection circuit 16 only turns on / selects / uses one receiving antenna (i.e., selects receiving antenna RX1 or RX2), thus interrupting the signals transmitted to the receiving circuit 14 by other receiving antennas.

[0158] In one embodiment, reference Figure 6A Taking the echo signals corresponding to the first triangular wave signals FS1 and FS3 as an example, in the first and second transmit / receive cycles, the receiving antenna RX1 receives the echo signal corresponding to the first signal FS1 (e.g., the first echo signal). In the third and fourth transmit / receive cycles, the receiving antenna RX2 receives the echo signal corresponding to the first signal FS3 (e.g., the second echo signal).

[0159] In another embodiment, a method corresponding to Figure 6A Taking the echo signals of the first sawtooth wave signals FS2 and FS4 as an example, in the first and second transmit / receive cycles, the receiving antenna RX1 receives the echo signal corresponding to the first signal FS3 (e.g., the first echo signal). In the third and fourth transmit / receive cycles, the receiving antenna RX2 receives the echo signal corresponding to the first signal FS4 (e.g., the second echo signal).

[0160] Two transmitting antennas TX1 and TX2 and two receiving antennas RX1 and RX2 can form four transmit / receive combinations. Each transmit / receive combination includes a combination of one of the two transmitting antennas TX1 and TX2 with one of the two receiving antennas RX1 and RX2. For example, Figure 6A The “TX1+RX1” shown represents the transmit / receive combination TRC2 of the transmitting antenna TX1 and the receiving antenna RX1, the “TX1+RX2” represents the transmit / receive combination TRC2 of the transmitting antenna TX1 and the receiving antenna RX2, the “TX2+RX1” represents the transmit / receive combination TRC2 of the transmitting antenna TX2 and the receiving antenna RX1, and the “TX2+RX2” represents the transmit / receive combination TRC2 of the transmitting antenna TX2 and the receiving antenna RX2.

[0161] In this embodiment, during the first and second transmit / receive cycles, a first detection mode corresponding to the first transmitted signal (corresponding to a first signal FS1 or FS2 with a bandwidth of frequency f1 to frequency f2) is executed; during the third and fourth transmit / receive cycles, a second detection mode corresponding to the second transmitted signal (corresponding to a first signal FS3 or FS4 with a bandwidth of frequency f3 to frequency f4) is executed. In one embodiment, the distance resolution of the first detection mode using the first transmitted signal with a smaller bandwidth (corresponding to a bandwidth of frequency f1 to frequency f2) is less than the distance resolution of the second detection mode using the second transmitted signal with a larger bandwidth (corresponding to a bandwidth of frequency f3 to frequency f4).

[0162] In one embodiment, please refer to Figure 2BThe amplifier PA included in the transmitting circuit 11 amplifies the two transmitted signals intended to be provided to the transmitting antennas TX1 and TX2. In addition, the amplifier PA provides corresponding power, gain and / or impedance matching according to the bandwidth of the transmitted signals.

[0163] It should be noted that the output power may still be adjusted due to antenna gain, mismatch or other factors.

[0164] In one embodiment, please refer to Figure 2B The receiving circuit 14 includes a low-noise amplifier (LNA) that amplifies the two echo signals received by the receiving antennas RX1 and RX2. Furthermore, the LNA provides corresponding gain and / or impedance matching based on the bandwidth of the echo signals.

[0165] Figure 6B This is a schematic diagram of two-dimensional detection according to another embodiment of the present invention. Please refer to... Figure 2B , Figure 6A and Figure 6B ,exist Figure 2B Under a structure (e.g., two transmitting antennas TX1, TX2 and two receiving antennas RX1, RX2), and operating in Figure 6A The switching of the TRC2 transceiver combination shown can determine range and angle information. The angle information can be the direction or angle of an external object relative to radar devices 10 and 10-2.

[0166] In one embodiment, due to the distance λ between transmitting antennas TX1 and TX2 D Set as λ HB / 2, and λ HB Let ∠HB be the wavelength of the transmitted signal with the higher center frequency transmitted by transmitting antenna TX1 and TX2. The field of view (FAR) covered by the transmitted signal with the higher center frequency on the radar coordinate system is ∠HB, and the field of view covered by the transmitted signal with the lower center frequency on the radar coordinate system is ∠LB. ∠LB is narrower than ∠HB. Furthermore, the relationship between ∠LB and ∠HB can be expressed as ∠LB = F. d ×±∠HB, coefficient F d f LB / f HB , where f LB The center frequency of the transmitted signal has a lower center frequency, and f HB This refers to the center frequency of a transmission signal with a relatively high center frequency. In this embodiment, we assume the center frequency of a transmission signal with a larger bandwidth is f. LB The center frequency of the transmission signal with a smaller bandwidth is f HBHowever, this is not a limitation. To ensure consistency in the benchmark for calculating angle information, when calculating angle information for transmission signals with lower center frequencies, it is necessary to utilize the coefficient F. d This is used to perform reverse calculations to compensate for angle information errors. For example, when calculating the angle for a transmission signal with a low center frequency, the angle needs to be divided by a coefficient F. d .by Figure 6B For example, the range of ∠LB is between +90° and F. d to -90°F d .

[0167] In this embodiment of the invention, transmission signals of different bandwidths are generated and transmitted in a time-division multiplexing manner, and receiving antennas RX1 and RX2 receive the corresponding echo signals in a time-division multiplexing manner. Therefore, when the two transmission signals are designed for narrowband and wideband applications respectively, Time Division Interlace Sensing (TDIS) can be provided, combining the two detection modes of narrowband and wideband. When the two transmission signals are designed with different center frequencies, dual-band detection can be provided.

[0168] Figure 7 This is a flowchart of a radar detection method according to an embodiment of the present invention. Please refer to... Figure 7 The system selects to execute either a first detection mode or a second detection mode (step S710). The detection power of the first detection mode is greater than the detection power of the second detection mode. Executing the first detection mode (step S720) includes: generating a first transmission signal (step S721), transmitting the first transmission signal (step S722), and receiving a first echo signal (step S723). The first echo signal is generated by the reflection of the first transmission signal by an external object. Executing the second detection mode (step S730) includes: generating a second transmission signal (step S731), transmitting the first transmission signal (step S732), and receiving a second echo signal (step S733). The second echo signal is generated by the reflection of the second transmission signal by an external object. Furthermore, the bandwidth of the second transmission signal is different from the bandwidth of the first transmission signal, and the bandwidth of the second echo signal is different from the bandwidth of the first echo signal.

[0169] about Figure 7 The implementation details of each step are described in detail in the foregoing embodiments and implementation methods, and will not be repeated here. In addition to being implemented in the form of circuits, the steps and implementation details of the embodiments of the present invention can also be implemented by a processor in software, and the embodiments of the present invention are not limited thereto.

[0170] In summary, in the radar device and radar detection method of the present invention, by time-division multiplexing transmission signals with different bandwidths and time-division multiplexing echo signals with different bandwidths, two detection modes can be executed alternately. Therefore, when operating in narrowband and broadband applications, the characteristics of both technologies (e.g., the longer detection range of narrowband applications and the finer distance resolution of broadband applications) can be combined to obtain more complete spatial information when detecting external objects.

[0171] Although the present invention has been disclosed above by way of embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make some modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A radar device, characterized by The radar device comprises: a transmitting circuit configured to generate a first transmission signal and a second transmission signal, wherein a bandwidth of the first transmission signal is different from a bandwidth of the second transmission signal; a transmitting antenna system configured to transmit the first transmission signal and the second transmission signal; and a receiving antenna system configured to receive a first echo signal, wherein the first echo signal is generated by reflection of the first transmission signal by an external object, and to receive a second echo signal, wherein the second echo signal is generated by reflection of the second transmission signal by an external object, and wherein a bandwidth of the first echo signal is different from a bandwidth of the second echo signal; wherein the first transmission signal and the first echo signal are used in a first detection mode, the second transmission signal and the second echo signal are used in a second detection mode, and a detection power of the first detection mode is greater than a detection power of the second detection mode. A distance resolution of the first detection mode is less than a distance resolution of the second detection mode.

2. The radar apparatus according to claim 1, characterized by The bandwidth of the first transmission signal is less than the bandwidth of the second transmission signal, and the bandwidth of the first echo signal is less than the bandwidth of the second echo signal.

3. The radar apparatus of claim 1, wherein The radar device further comprises a control circuit coupled to the transmitting circuit and configured to generate one or more control signals, wherein the one or more control signals vary in correspondence with a period of a first signal.

4. The radar apparatus of claim 1, wherein A signal frame time comprises a plurality of transmission and reception periods, and the radar device is configured to select only one of the first detection mode and the second detection mode to be performed in each of the transmission and reception periods in the signal frame time in accordance with the one or more control signals.

5. The radar apparatus of claim 4, wherein, The radar device further comprises a selection circuit coupled to the control circuit and the receiving antenna system, wherein a signal frame time comprises a plurality of transmission and reception periods, the receiving antenna system comprises a first receiving antenna and a second receiving antenna, and the selection circuit is configured to select only the first receiving antenna to receive the first echo signal or only the second receiving antenna to receive the second echo signal in each of the transmission and reception periods in the signal frame time in accordance with the one or more control signals.

6. The radar apparatus of claim 4, wherein, A size of the first receiving antenna is less than a size of the second receiving antenna.

7. The radar apparatus of claim 6, wherein, A signal frame time comprises a plurality of transmission and reception periods, the transmitting antenna system comprises a first transmitting antenna, and the transmitting circuit is configured to select only one of the first transmission signal and the second transmission signal to be generated in each of the transmission and reception periods in the signal frame time in accordance with the one or more control signals, such that the first transmitting antenna is configured to transmit only one of the first transmission signal and the second transmission signal in each of the transmission and reception periods in the signal frame time.

8. The radar apparatus of claim 4, wherein, ​ 9. The radar apparatus of claim 4, wherein, The radar device further includes a selection circuit coupled to the control circuit and the transmitting antenna system, wherein a signal frame time includes a plurality of transmission cycles, the transmitting antenna system includes a first transmitting antenna and a second transmitting antenna, the transmitting circuit is configured to select only one of the first transmitting signal and the second transmitting signal to be generated in each of the transmission cycles in the signal frame time according to the one or more control signals, and the selection circuit is configured to select only the first transmitting antenna to transmit one of the first transmitting signal and the second transmitting signal in each of the transmission cycles in the signal frame time according to the one or more control signals, or to select only the second transmitting antenna to transmit one of the first transmitting signal and the second transmitting signal in each of the transmission cycles in the signal frame time according to the one or more control signals.

10. The radar apparatus of claim 9, wherein, a distance between the first transmit antenna and the second transmit antenna is λ HB / 2, where λ HB is a wavelength of a higher one of the first transmitted signal and the second transmitted signal.

11. The radar apparatus of claim 4, wherein, The radar device further includes a frequency synthesizer or a pulse generator coupled to the control circuit and configured to generate the first signal, wherein the first signal is a continuous wave signal or a pulse signal; and a clock generator coupled to the frequency synthesizer or the pulse generator and configured to generate a clock signal, wherein the frequency synthesizer or the pulse generator generates the first signal according to the clock signal, and the control circuit synchronizes the first signal according to the clock signal. The radar device further includes a receiving circuit and a processing unit, wherein the first echo signal or the second echo signal forms a radio frequency signal, the receiving circuit is configured to generate an internal signal according to the radio frequency signal and the first signal, the internal signal includes a plurality of internal sub-signals formed in the transmission cycles in the signal frame time, and the processing unit is coupled to the receiving circuit and configured to determine a spatial information of the external object according to the internal sub-signals.

12. The radar apparatus of claim 5, wherein, The transmitting circuit further includes an amplifier coupled to the transmitting antenna system, and the receiving circuit further includes a low noise amplifier coupled to the receiving antenna system.

13. The radar apparatus of claim 12, wherein, The amplifier is configured to output different power in the first detection mode and the second detection mode according to the one or more control signals.

14. The radar apparatus of claim 13, wherein, The radar device further includes a selection circuit, a first matching circuit, a second matching circuit, and a third matching circuit, wherein the transmitting antenna system includes a first transmitting antenna, the receiving antenna system includes a first receiving antenna and a second receiving antenna, the first matching circuit is coupled between the selection circuit and the first receiving antenna, the second matching circuit is coupled between the selection circuit and the second receiving antenna, and the third matching circuit is coupled between the transmitting circuit and the first transmitting antenna, wherein a matching bandwidth of the first matching circuit is smaller than a matching bandwidth of the second matching circuit, and a matching bandwidth of the third matching circuit is larger than the matching bandwidth of the first matching circuit.

15. The radar apparatus of claim 4, wherein, ​ 16. The radar apparatus of claim 4, wherein, The radar device further includes a selection circuit, a first matching circuit, a second matching circuit, a third matching circuit, and a fourth matching circuit, wherein the transmitting antenna system includes a first transmitting antenna and a second transmitting antenna, the receiving antenna system includes a first receiving antenna and a second receiving antenna, the first matching circuit is coupled between the selection circuit and the first receiving antenna, the second matching circuit is coupled between the selection circuit and the second receiving antenna, the third matching circuit is coupled between the selection circuit and the first transmitting antenna, and the fourth matching circuit is coupled between the selection circuit and the second transmitting antenna, wherein a matching bandwidth of the first matching circuit is less than a matching bandwidth of the second matching circuit, a matching bandwidth of the third matching circuit is greater than the matching bandwidth of the first matching circuit, and a matching bandwidth of the fourth matching circuit is greater than the matching bandwidth of the first matching circuit.

17. A radar detection method, characterized by, The radar device further includes: selecting to perform a first detection mode or a second detection mode; wherein performing the first detection mode includes: generating a first transmission signal; transmitting the first transmission signal; and receiving a first echo signal, wherein the first echo signal is generated by the first transmission signal being reflected by an external object; wherein performing the second detection mode includes: generating a second transmission signal, wherein a bandwidth of the second transmission signal is different from a bandwidth of the first transmission signal; transmitting the second transmission signal; and receiving a second echo signal, wherein the second echo signal is generated by the second transmission signal being reflected by the external object, and wherein a bandwidth of the second echo signal is different from a bandwidth of the first echo signal; wherein a detection power of the first detection mode is greater than a detection power of the second detection mode.

18. The radar detection method of claim 17, wherein, The step of selecting to perform the first detection mode or the second detection mode further includes: generating one or more control signals, wherein the one or more control signals vary in accordance with a period of a first signal; and selecting to perform only one of the first detection mode and the second detection mode in each of a plurality of transmission and reception cycles in a signal frame time in accordance with the one or more control signals.

19. The radar detection method of claim 18, wherein, The step of selecting to perform the first detection mode or the second detection mode further includes: selecting to receive only one of the first echo signal and the second echo signal in each of the transmission and reception cycles in the signal frame time in accordance with the one or more control signals.

20. The radar detection method of claim 18, wherein, The step of selecting to perform the first detection mode or the second detection mode further includes: selecting to generate only one of the first transmission signal and the second transmission signal in each of the transmission and reception cycles in the signal frame time in accordance with the one or more control signals, and selecting to transmit only one of the first transmission signal and the second transmission signal in each of the transmission and reception cycles in the signal frame time in accordance with the one or more control signals.

21. The radar detection method of claim 18, wherein, The radar detection method further includes: forming a radio frequency signal in accordance with the first echo signal or the second echo signal; generating an internal signal according to the radio frequency signal and the first signal, wherein the internal signal comprises a plurality of internal sub-signals formed in the transmission period of the signal frame time; and determining a spatial information of the external object according to the internal sub-signals.

22. The radar detection method of claim 17, wherein, The bandwidth of the first transmission signal is less than the bandwidth of the second transmission signal, and the bandwidth of the first echo signal is less than the bandwidth of the second echo signal.

23. A radar apparatus, characterized by comprising: comprising: a transmitting circuit for generating a first transmission signal and a second transmission signal, wherein the bandwidth of the first transmission signal is different from the bandwidth of the second transmission signal; a transmitting antenna system for transmitting the first transmission signal and the second transmission signal; a receiving antenna system comprising a first receiving antenna and a second receiving antenna, wherein the first receiving antenna is used to receive a first echo signal generated by the first transmission signal reflected by an external object, wherein the second receiving antenna is used to receive a second echo signal generated by the second transmission signal reflected by the external object, and wherein the bandwidth of the first echo signal is different from the bandwidth of the second echo signal; a control circuit for generating one or more control signals; and a selection circuit coupled to the control circuit and the receiving antenna system, and used to select the first receiving antenna to receive the first echo signal or select the second receiving antenna to receive the second echo signal according to the one or more control signals generated by the control circuit. ​

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