Radar system
The radar system addresses the limitations of conventional marine radars by using a rotating mechanism with unique frequency signals for each antenna, simplifying mounting and reducing equipment size and complexity while improving detection performance.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- KODEN ELECTRONICS CO LTD
- Filing Date
- 2025-08-22
- Publication Date
- 2026-07-08
AI Technical Summary
Conventional marine radars use lower frequencies and mechanical drive systems, leading to larger antenna dimensions and limited rotation speed, which complicates detection of fast-moving targets and increases equipment size and cost, especially when used for monitoring small flying objects like drones.
A radar system with N antenna devices and a distributor/combiner arranged on a rotating mechanism, where each antenna has a unique frequency for its received IF signal, eliminating the need for a transceiver on the rotating mechanism.
The system allows for easy mounting on a rotating mechanism, reduces device size, and enhances detection performance by eliminating the need for multiple transceivers, thus simplifying the mechanical design and reducing the complexity of the rotary joint.
Smart Images
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Abstract
Description
[Technical Field]
[0001] This invention relates to a radar system that incorporates an antenna on a rotating mechanism. [Background technology]
[0002] The most basic form of radar is a search radar that uses a mechanically driven antenna with a fan beam pattern that has a narrow horizontal directivity and a relatively wide vertical directivity, rotating horizontally. This type of radar consists of a single antenna unit and a transceiver, and determines the position of reflectors based on the time from transmission to reception and the antenna's directivity angle. Due to its simple configuration and relatively low cost, it is widely used in marine radar and other applications.
[0003] In recent years, the introduction of autonomous driving technology into automobiles has become widespread. In autonomous driving of automobiles, multiple sensors such as millimeter-wave radar, stereo cameras, and LiDAR (Light Detection And Ranging) are used to recognize the surrounding environment and determine driving operations (Patent Document 1, etc.). The momentum for introducing autonomous driving is also seen in ships. However, one difference between automobiles and ships is the time required to change course, with ships being overwhelmingly slower. Therefore, in the case of ships, it is necessary to grasp a wider range of the surrounding environment. Because millimeter-wave radar has a limited maximum detection range, lower frequencies such as the X-band, which have been used conventionally, are suitable for autonomous navigation of ships. In addition, in autonomous driving, a higher update rate (frequency of updating measurement results) is desirable from the perspective of grasping the surrounding environment in more detail and responding to sudden events. The update rate of measurement results generally depends on the rotation speed of the antenna, so it is desirable for the rotation speed of the radar antenna to be high. One method of not increasing the rotation speed by using multiple radars in different directions is the technology described in Patent Document 2.
[0004] The technology described in Patent Document 2 is a radar having multiple combinations of antenna devices and transceivers. Figure 1 shows an example of a radar with one antenna mounted on a rotating mechanism. Figure 1(A) is a plan view of the antenna. The antenna rotates horizontally. Figure 1(B) is an output screen from the radar. The darkly colored areas are being updated. Figure 2 shows an example of a radar with four antennas mounted on a rotating mechanism. Figure 2(A) is a plan view of the antenna. The antenna rotates horizontally. Figure 2(B) is an output screen from the radar. The darkly colored areas are being updated. It can be seen that the update rate is higher even if the rotation speed is the same because there are four antennas. Patent Document 2 is an example of using multiple antennas. Figure 3 shows an example of a radar having multiple combinations of antenna devices and transceivers. The radar system in Figure 3 has N antenna devices 9101,...,910 N and N transceivers 9301, ..., 930 N It has N antenna devices 9101, ..., 910 N and N transceivers 9301, ..., 930 N This is mounted on the rotating mechanism 950. Transceiver 9301,...,930 N The connection to the outside is made via the rotary joint 940. [Prior art documents] [Patent Documents]
[0005] [Patent Document 1] Japanese Patent Publication No. 2019-66240 [Patent Document 2] Japanese Patent Application Publication No. 9-236656 [Overview of the project] [Problems that the invention aims to solve]
[0006] However, conventional marine radars use lower frequencies compared to millimeter waves, resulting in larger antenna dimensions. Furthermore, their mechanical drive system limits the speed at which the antenna can rotate. While it is possible to change the antenna's directionality control to an electronic scanning system, this would increase the size and cost of the equipment.
[0007] Because marine radar is widely used worldwide and readily available, it is also being used for purposes other than marine applications. One such application is the monitoring of the operation of small flying objects (drones), which are expected to see increased use in the future. However, lightweight design is a priority for typical drones, and both the material and size of the aircraft contribute to reducing the radar cross-section, making detection difficult. One countermeasure is to reduce the rotation speed of the antenna to increase the number of times radio waves are emitted to the target, thereby improving detection performance through cumulative effect. However, this makes tracking fast-moving targets difficult. In the configuration shown in Figure 3, the antenna devices 9101,...,910 are connected to the rotating mechanism 950. N and transmitting and receiving devices 9301, ..., 930 N The need to incorporate a combination of components leads to a larger device size. Additionally, the increased number of wires for external connections results in a larger rotary joint 940.
[0008] The present invention aims to provide a radar system that is easy to mount on a rotating mechanism. [Means for solving the problem]
[0009] The radar system of the present invention comprises N antenna devices, a distributor / combiner, and a transceiver. N is an integer of 2 or more. The N antenna devices and the distributor / combiner are arranged on a rotating mechanism so that the directivity angles of the N antenna devices do not overlap. The antenna device comprises an antenna, a transmit / receive discriminator, a frequency converter, and an antenna frequency discriminator. The transceiver comprises a clock oscillator, a transmitter, a transmit / receive frequency discriminator, and an A / D converter. The transmit / receive discriminator outputs the transmit RF signal from the antenna frequency discriminator to the antenna and the received RF signal from the antenna to the frequency converter. The frequency converter converts the received RF signal into a received IF signal of a different frequency for each antenna and outputs it to the antenna frequency discriminator. The antenna frequency discriminator outputs the transmit RF signal from the distributor / combiner to the transmit / receive discriminator and the received IF signal from the frequency converter to the distributor / combiner. The distributor / combiner distributes the transmitted RF signal from the transmit / receive frequency discriminator to N signals, outputs them to N antenna frequency discriminators, and outputs a combined received IF signal, which is the combined signal from the N antenna frequency discriminators, to the transmit / receive frequency discriminator. The clock oscillator generates a clock signal for processing within the transmitting / receiving device. The transmitting unit outputs the transmitted RF signal to the transmit / receive frequency discriminator. The transmit / receive frequency discriminator outputs the transmitted RF signal from the transmitting unit to the distributor / combiner, and also outputs the combined received IF signal from the distributor / combiner, or the combined received IF signal, to the A / D converter, which is obtained by discriminating the received IF signal from the N antenna frequency discriminators into N received IF signals. The A / D converter converts the signals from the transmit / receive frequency discriminator into digital signals. [Effects of the Invention]
[0010] According to the radar system of the present invention, the received IF signal sent from the antenna device to the transceiver has a different frequency for each antenna. Therefore, there is no need to provide a transceiver for each antenna device, and thus there is no need to mount the transceiver on the rotating mechanism. Thus, it is easy to mount on the rotating mechanism. [Brief explanation of the drawing]
[0011] [Figure 1]A diagram showing an example of a radar system with a single antenna mounted on a rotating mechanism. [Figure 2] A diagram showing an example of a radar system with four antennas mounted on a rotating mechanism. [Figure 3] A diagram showing an example of a radar system with multiple combinations of antenna devices and transceivers. [Figure 4] A diagram showing an example configuration of the radar system of the present invention. [Figure 5] A diagram showing an example configuration of the antenna device in Example 1. [Figure 6] A diagram showing an example configuration of the transmitting and receiving device in Example 1. [Figure 7] A diagram illustrating the overview of the radar system in Example 1. [Figure 8] This figure shows an example of the configuration of the transmitting and receiving device in Example 1, Modification 1. [Figure 9] This figure shows an example of the configuration of the transmitting and receiving device in Example 1 Modification 2. [Figure 10] A diagram showing an example configuration of the antenna device in Example 2. [Figure 11] A diagram showing an example configuration of the transceiver in Example 2. [Figure 12] A diagram showing an example configuration of the antenna device in Example 3. [Figure 13] A diagram showing an example configuration of the transceiver in Example 3. [Figure 14] A diagram showing an example of the control signal transmission method in Example 3. [Modes for carrying out the invention]
[0012] The embodiments of the present invention will be described in detail below. Components having the same function will be given the same number, and redundant explanations will be omitted. In the following description, N is an integer greater than or equal to 2, and n is an integer between 1 and N. [Examples]
[0013] Fig. 4 shows a configuration example of the radar system of Example 1. Fig. 5 is a configuration example of the antenna device of Example 1, and Fig. 6 is a configuration example of the transceiver device of Example 1. Fig. 7 is a diagram for explaining the outline of the radar system of Example 1. The radar system includes N antenna devices 1001,…,100 N and a distribution / combiner 300 and a transceiver device 200. The N antenna devices 1001,…,100 N and the distribution / combiner 300 are arranged in a rotation mechanism 950 so that the direction angles of the N antenna devices 1001,…,100 N do not overlap. The connection between the distribution / combiner 300 and the transceiver device 200 is made via a rotary joint 440. A single-core coaxial type widely used for RF signal transmission is assumed for the rotary joint 440. The rotation mechanism 950 rotates the N antenna devices 1001,…,100 N and the distribution / combiner 300 in the horizontal direction.
[0014] The antenna device 100 n includes an antenna 110 n , a transmit / receive discriminator 120 n , a frequency conversion unit 140 n , and an antenna frequency discriminator 130 n . The transceiver device 200 includes a clock oscillator 240, a transmitter 210, a transmit / receive frequency discriminator 220, an A / D conversion unit 230, a receive channel discriminator 250, and a power supply unit 260.
[0015] The antenna 110 n assumes an antenna similar to a conventional radar. For example, an array antenna with its longitudinal direction facing the horizontal direction may be used. With an array antenna whose longitudinal direction faces the horizontal direction, a fan beam pattern with a narrow horizontal direction and a relatively wide vertical direction can be formed. Therefore, it is easy to arrange the N antenna devices 1001,…,100 N in the rotation mechanism 950 so that their direction angles do not overlap.
[0016] The transmit / receive discriminator 120 n is the antenna frequency discriminator 130 nThe transmitted RF signal from antenna 110 n It outputs to antenna 110 n The RF signal received from the frequency conversion unit 140 n Output to [this location].
[0017] Frequency conversion unit 140 n The received RF signal is transmitted to antenna 110 n Each is converted into a receiving IF signal of a different frequency, and the antenna frequency discriminator 130 n Output to: Frequency conversion unit 140 n is the frequency converter 141 n , local oscillator 142 n , reference oscillator 143 n , constant voltage device 144 n Controller 145 n It is sufficient to have the following: Frequency converter 141 n The received RF signal and the local oscillator 142 n The local oscillator signal input from is multiplied and the received IF signal is output. n This includes RF / IF amplifiers, band-limiting filters, etc. Local oscillator 142 n This is the reference oscillator 143 n Based on the reference signal from, controller 145 n The local oscillator signal is transmitted to the frequency converter 141 according to the control of the device. n Output to: Reference oscillator 143 n is a constant voltage device 144 n The local oscillator 142 is driven by a DC power supply input from the local oscillator and receives a predetermined reference signal. n Output to: Controller 145 n It has built-in software and constant voltage 144 n When a DC power supply is input, the local oscillator 142 spontaneously generates a predetermined control signal. n It is sent to the local oscillator 142. The predetermined control signal is, for example, the local oscillator 142. n This is the frequency of the local oscillator signal output by the constant voltage device 144. n Antenna frequency discriminator 130 n DC power supplied from is converted to frequency converter 141 n , local oscillator 142 n, reference oscillator 143 n Controller 145 n Then it converts and outputs the required power supply voltages. If all required power supply voltages are equal, the constant voltage device 144 n This may be omitted. The frequency of the local oscillator signal is determined by the N antenna devices 1001, ..., 100 N Each of these values is set to be different, and each of the N received IF signals has a different frequency. In this way, each antenna device 100 n It becomes possible to identify received signals by frequency.
[0018] Antenna frequency discriminator 130 n The transmit RF signal from the distributor / combiner 300 is transmitted to the send / receive discriminator 120. n Output to the frequency conversion unit 140 n The received IF signal is output to the distributor / combiner 300. Also, the antenna frequency discriminator 130 n The DC power from the distributor / combiner 300 is converted to the frequency conversion unit 140. n 144 constant voltage device n To supply. Antenna frequency discriminator 130 n This can be composed of, for example, an RF high-pass filter, an IF band-pass filter, and a DC-passing inductor. In this way, the antenna frequency discriminator 130 n By using a single signal line (=1 core) between the distributor / combiner 300 and the signal, it becomes possible to transmit RF, IF, and DC power signals superimposed.
[0019] The distributor / combiner 300 distributes the transmitted RF signal from the transmit / receive frequency discriminator 220 to N antenna frequency discriminators 1301, ..., 130 N Output to N antenna frequency discriminators 1301, ..., 130 N The combined received IF signal, which is a signal obtained by combining the received IF signals from the sources, is output to the transmit / receive frequency discriminator 220. The distributor / combiner 300 distributes the frequencies from DC to RF signals into N parts. For example, a resistor distributor / combiner can be used for the distributor / combiner 300.
[0020] The clock oscillator 240 generates a clock signal for processing within the transceiver 200. The clock oscillator 240 should generate a clock signal with a frequency at least twice that of the highest frequency among the N received IF signals and output the clock signal to the A / D conversion unit 230. If the transmitter 210 is a solid-state radar with a semiconductor amplifier, the clock signal is also output to the transmitter 210.
[0021] The transmitting unit 210 outputs a transmit RF signal to the transmit / receive frequency discriminator 220. The transmitting unit 210 is the same as the transmitting unit of a conventional transceiver, and generates a transmit RF signal and outputs it to the transmit / receive frequency discriminator 220.
[0022] The transmit / receive frequency discriminator 220 outputs the transmit RF signal from the transmit unit 210 to the distributor / combiner 300, and also outputs the combined receive IF signal from the distributor / combiner 300 to the A / D converter 230. The transmit / receive frequency discriminator 220 is connected to the antenna frequency discriminator 130. n It has the same function.
[0023] The A / D converter 230 converts the combined received IF signal into a combined digital IF signal and outputs it to the received channel discriminator 250. The A / D converter 230 operates with a clock signal that is at least twice the frequency of the highest of the N received IF signals.
[0024] The receiving channel discriminator 250 receives the combined digital IF signal from the antenna device 100. n The signal is divided into individual digital IF signals. The receiving channel discriminator 250 has N bandpass filters corresponding to the frequencies of the N received IF signals, and the combined digital IF signal is connected to N antenna devices 1001, ..., 100 N The signal is divided into corresponding signals.
[0025] The power supply unit 260 has N antenna devices 1001, ..., 100 N The power used is generated and transmitted to each antenna device 100 via the transmit / receive frequency discriminator 220, rotary joint 440, and distributor / combiner 300. n It supplies power to it.
[0026] Next, with reference to Figure 7, the operation when the number of antenna devices is set to two will be specifically explained. Figure 7 shows specific examples of antenna frequency discriminators 1301, 1302 and transmit / receive frequency discriminator 220. The transmit RF signal generated by the transmitter 210 is output to the distributor / combiner 300 via the transmit / receive frequency discriminator 220 and rotary joint 440. The frequency of the transmit RF signal at this time is 9410 MHz. The distributor / combiner 300 splits the transmit RF signal into two and outputs transmit RF signals of equal level to the two antenna devices 1001 and 1002. Antenna device 100 n The transmitted RF signal input to the antenna frequency discriminator 130 n , transmission / reception valve 120 n via antenna 110 n It is radiated into space. Antenna 110 n The signal emitted from and reflected by surrounding objects is received as an RF signal by antenna 110. n Input to, send / receive discriminator 120 n via frequency conversion unit 140 n It is input to the frequency conversion unit 140. n Next, the received RF signal is frequency-converted to the received IF signal, using the local oscillator 142. n By slightly changing the frequency of the local oscillator signal output from the antenna device 1001, 1002, each antenna device 100 n The frequency of the received IF signal output from is changed. For example, the frequencies of the received IF signals are set to 30MHz and 50MHz, respectively. Frequency conversion unit 140 n The received IF signal output from the antenna frequency discriminator 130 nIt is output to the A / D conversion unit 230 via the distribution / synthesizer 300, the rotary joint 440, and the transmission / reception frequency discriminator 220. Here, if the frequency of the clock signal of the clock oscillator 240 is 150 MHz, the Nyquist frequency is 75 MHz, and a combined reception IF signal having two types of frequencies can be received. In the A / D conversion unit 230, the combined reception IF signal is converted into a combined digital IF signal. If the digital IF signal is input to band-pass filters of 30 MHz and 50 MHz respectively in the reception channel discriminator 250, the reception signals in the two antenna devices 1001 and 1002 can be processed individually, and the measurement results of the two antenna devices 1001 and 1002 can be obtained simultaneously.
[0027] According to the radar system of the first embodiment, the reception IF signals sent from the antenna devices 1001,..., 100 N to the transmission / reception device 200 have different frequencies for each antenna. Therefore, since it is not necessary to provide the transmission / reception device 200 for each antenna device 100 n it is not necessary to mount the transmission / reception device 200 on the rotating mechanism 950. Thus, the radar system of the first embodiment is easy to mount on the rotating mechanism 950. [Modification 1]
[0028] Fig. 8 shows a configuration example of the transmission / reception device according to Modification 1 of the first embodiment. The transmission / reception device 201 includes a clock oscillator 240, a transmission unit 210, a transmission / reception frequency discriminator 221, A / D conversion units 成2311,..., 231 N and a power supply unit 260. The transmission / reception frequency discriminator 221 discriminates the combined reception IF signal into N reception IF signals from N antenna frequency discriminators 1301,..., 130[[ID=...]] N and outputs each of the N reception IF signals to the corresponding A / D conversion units 2311,..., 231 N . The A / D conversion unit 231 n outputs the digital IF signal for each antenna device 100 n . The rest is the same as that of the first embodiment. [Modification 2]
[0029] Figure 9 shows an example configuration of a transceiver in a modified example 2 of Embodiment 1. The transceiver 202 comprises a clock oscillator 240, a transmitting unit 210, a transmit / receive frequency discriminator 221, an IF switch 280, an A / D converter 230, and a power supply unit 260. The transmit / receive frequency discriminator 221 receives a combined received IF signal from N antenna frequency discriminators 1301, ..., 130 N The N received IF signals, selected from the received IF signals, are output to the IF switch 280. The IF switch 280 selects one received IF signal from the N received IF signals and outputs it to the A / D converter 230. The A / D converter 230 converts the input received IF signal into a digital IF signal. The rest is the same as in Embodiment 1.
[0030] Furthermore, the configuration shown in Figures 8 and 9 allows for a reduction in the clock signal frequency by appropriately selecting the frequency of the received IF signal. For example, by keeping one of the received IF signals at 30 MHz and the other at 125 MHz, and processing the former with oversampling and the latter with undersampling, the clock signal frequency can be reduced to 75 MHz. In addition, the use of undersampling is useful for increasing the number of antenna devices N that perform simultaneous measurements, for example, by setting the clock signal frequency to 150 MHz and using received IF frequencies of 30 MHz and 50 MHz, or 180 MHz and 200 MHz, with the first two frequencies being oversampled and the latter two undersampling. [Examples]
[0031] Figure 4 shows an example configuration of the radar system of Example 2. Figure 10 shows an example configuration of the antenna device of Example 2, and Figure 11 shows an example configuration of the transceiver of Example 2. The radar system consists of N antenna devices 1031,...,103 N It has a distributor / combiner 300 and a transceiver 203. N antenna devices 1031, ..., 103 N The distributor / combiner 300 has N antenna devices 1031, ..., 103 NThey are arranged in the rotation mechanism 950 so that the direction angles do not overlap. The connection between the distributor / combiner 300 and the transceiver 203 is made via the rotary joint 440. The rotary joint 440 is assumed to be of a single-core coaxial type widely used for RF signal transmission applications. The rotation mechanism 950 rotates the N antenna devices 1031,…,103 N and the distributor / combiner 300 in the horizontal direction.
[0032] The antenna device 103 n comprises an antenna 110 n , a transmit / receive discriminator 120 n , a frequency conversion unit 150 n , and an antenna frequency discriminator 133 n . The transceiver 203 comprises a clock oscillator 240, a transmitter 210, a transmit / receive frequency discriminator 223, an A / D conversion unit 230, a receive channel discriminator 250, a power supply unit 260, and a reference oscillator 243. The antenna 110 n , the transmit / receive discriminator 120 n , the clock oscillator 240, the transmitter 210, the A / D conversion unit 230, the receive channel discriminator 250, and the power supply unit 260 are the same as in the first embodiment.
[0033] The reference oscillator 243 is arranged inside the transceiver 203 and generates a reference signal. The transmit / receive frequency discriminator 223 sends the reference signal from the reference oscillator 243 together with the transmit RF signal from the transmitter 210 to the antenna devices 1031,…,103 N . The antenna frequency discriminator 133 n outputs the transmit RF signal from the distributor / combiner 300 to the transmit / receive discriminator 120 n and outputs the received IF signal from the frequency conversion unit 150 n to the distributor / combiner 300. Also, the antenna frequency discriminator 133 n supplies the DC power from the distributor / combiner 300 to the voltage regulator 144 n of the frequency conversion unit 150 n .
[0034] The frequency conversion unit 150 n comprises a frequency converter 141 n , local oscillator 152 n , constant voltage device 144 n Controller 145 n It is sufficient to have the following: Local oscillator 152 n Based on the reference signal from the reference oscillator 243, the controller 145 n The local oscillator signal is transmitted to the frequency converter 141 according to the control of the device. n Output to: Frequency converter 141 n , constant voltage device 144 n Controller 145 n This is the same as in Example 1.
[0035] Modifications 1 and 2 of Example 1 can also be applied to Example 2. The radar system of Example 2 can achieve the same effects as the radar system of Example 1. [Examples]
[0036] Figure 4 shows an example configuration of the radar system of Example 3. Figure 12 shows an example configuration of the antenna device of Example 3, and Figure 13 shows an example configuration of the transceiver of Example 3. The radar system consists of N antenna devices 1041,...,104 N It has a distributor / combiner 300 and a transceiver 204. N antenna devices 1041,...,104 N The distributor / combiner 300 has N antenna devices 1041, ..., 104 N The antennas are arranged on the rotating mechanism 950 so that their directional angles do not overlap. The connection between the distributor / combiner 300 and the transceiver 204 is made via a rotary joint 440. The rotary joint 440 is assumed to be a single-core coaxial type widely used for RF signal transmission. The rotating mechanism 950 is connected to N antenna devices 1041, ..., 104 N The distributor / combiner 300 is then rotated horizontally.
[0037] Antenna device 104 n Antenna 110 n , transmission / reception valve 120 n , frequency conversion unit 160 n Antenna frequency discriminator 134 n Switcher 180 nThe transceiver 204 includes a clock oscillator 240, a transmitter 210, a transmit / receive frequency discriminator 224, an A / D converter 230, a receive channel discriminator 250, a power supply unit 260, a reference oscillator 243, a control modulator 265, and an antenna device control unit 270. Antenna 110 n , transmission / reception valve 120 n The clock oscillator 240, transmitter 210, A / D converter 230, receiver channel discriminator 250, and power supply 260 are the same as in Example 1. The reference oscillator 243 is the same as in Example 2.
[0038] The transmit / receive frequency discriminator 224 transmits the RF signal from the transmit unit 210 along with the reference signal from the reference oscillator 243 and the switch 180. n The signals that control the antenna devices 1041, ..., 104 N Send to: Antenna frequency discriminator 134 n The transmit RF signal from the distributor / combiner 300 is transmitted to the send / receive discriminator 120. n Output to the frequency conversion unit 160 n The received IF signal is output to the distributor / combiner 300. Also, the antenna frequency discriminator 134 n The DC power from the distributor / combiner 300 is converted to the frequency conversion unit 160. n 144 constant voltage device n To supply.
[0039] Frequency conversion unit 160 n is the frequency converter 141 n , local oscillator 152 n , constant voltage device 144 n , control demodulator 165 n It is equipped with a local oscillator 152. n This is the same as in Example 2. Frequency converter 141 n , constant voltage device 144 n This is the same as in Example 1.
[0040] Switch 180 n The frequency conversion unit 160 n The received RF signal to is blocked. The antenna device control unit 270 outputs the transmitted RF signal, and the switch 180 nThe frequency conversion unit 160 n Control to block the received RF signal to the antenna device control unit 270. The control signal from the antenna device control unit 270 is modulated by the control modulator 265 and then controlled by the control demodulator 165. n It was demodulated, and switch 180 n Control.
[0041] Figure 14 shows an example of a control signal transmission method. In Figure 14, it is assumed that the antenna device control unit 270 outputs 3-bit control signals A, B, and C. The control modulator 265 multiplies each of the control signals A to C by different coefficients and combines them to generate a control-modulated signal. In Figure 14, A to C are converted to (1V, 0V), (2V, 0V), and (4V, 0V) respectively and then combined. The control-modulated signal is a signal in which the magnitude of the level contains 3 bits of information. The control-modulated signal output from the control modulator 265 is further superimposed with the DC power supply component output from the power supply unit 260 by the transmit / receive frequency discriminator 224 to the antenna device 104 n It is transmitted to [the specified location]. In Figure 14, the DC power supply voltage is set to 5V. Antenna device 104 n Antenna frequency discriminator 134 n Next, the DC power supply component is removed from the transmitted signal, and the control-modulated signal is processed by the control-demodulator 165 n Output to: Control demodulator 165 n Next, 3 bits of information are read from the magnitude of the control demodulation signal level to generate a control signal, and the control signal is output. By integrating the antenna device control unit 270 with the transceiver 204, the frequency conversion unit 160 is used while the transmitted RF signal is being output. n Switch 180 that blocks the RF input n The antenna device 104 controls the transmission for each transmission. n It has the advantage of being easily controllable.
[0042] Modifications 1 and 2 of Example 1 can also be applied to Example 3. The radar system of Example 3 can obtain the same effects as the radar system of Example 1. In addition, in the case of Example 3, the switch 180 is used at the timing of outputting the transmitted RF signal. n The frequency conversion unit 160 nSince it can be controlled to block the received RF signal to the antenna, crosstalk can be attenuated. An advantage of having the antenna control unit 270 within the transceiver 204 is that the antenna 104 n Switcher 180 inside n An example of control has been shown, but the antenna device control unit 270 controls the antenna device 104 n The advantage of being able to control this can be used for other processes. For example, the antenna device control unit 270 can perform control in accordance with the timing of processing within the transceiver 204. [Explanation of Symbols]
[0043] 100 n ,103 n ,104 n ,910 n Antenna equipment 110 n Antenna 120 n Sending and receiving discriminator 130 n ,133 n ,134 n Antenna frequency discriminator 140 n ,150 n ,160 n Frequency conversion section 141 n Frequency converter 142 n ,152 n Local oscillator 143 n ,243 Reference oscillator 144 n Constant voltage device 145 n Controller 165 n Control demodulator 180 n Switch 200,201,202,203,204,930 n Transceiver 210 Transmitter 220, 221, 223, 224 Transmit / Receive Frequency Discriminator 230,231 n A / D conversion unit 240 Clock oscillator 250 Receiving channel discriminator 260 Power supply unit 265 Control modulator 270 Antenna device control unit 280 IF Switch, 300 Distribution / Combining Device 440,940 Rotary joint 950 Rotating mechanism
Claims
1. A radar system having N antenna devices, a distributor / combiner, and a transceiver, N is an integer greater than or equal to 2, The N antenna devices and the distributor / combiner are arranged in a rotating mechanism such that the directivity angles of the N antenna devices do not overlap. The antenna device comprises an antenna, a transmit / receive discriminator, a frequency converter, and an antenna frequency discriminator. The aforementioned transmitting and receiving device comprises a clock oscillator, a transmitting unit, a transmit / receiving frequency discriminator, and an A / D conversion unit. The transmit / receive discriminator outputs the transmit RF signal from the antenna frequency discriminator to the antenna, and outputs the receive RF signal from the antenna to the frequency conversion unit. The frequency conversion unit converts the received RF signal into a received IF signal of a different frequency for each antenna and outputs it to the antenna frequency discriminator. The antenna frequency discriminator outputs the transmitted RF signal from the distributor / combiner to the transmit / receive discriminator, and outputs the received IF signal from the frequency conversion unit to the distributor / combiner. The aforementioned distributor / combiner is connected to the transmitting / receiving device via a single-core coaxial rotary joint, distributes the transmitted RF signal from the transmit / receive frequency discriminator to N signals and outputs them to N antenna frequency discriminators, and outputs a combined received IF signal, which is a signal obtained by combining the received IF signals from the N antenna frequency discriminators, to the transmit / receive frequency discriminator. The clock oscillator generates a clock signal for processing within the transmitting and receiving device. The transmitting unit outputs the transmitted RF signal to the transmitting / receiving frequency discriminator. The transmit / receive frequency discriminator outputs the transmit RF signal from the transmit unit to the distributor / combiner, and outputs the combined receive IF signal from the distributor / combiner, or the combined receive IF signal, to the A / D converter, which is obtained by discriminating the receive IF signal from N antenna frequency discriminators into N receive IF signals. The A / D conversion unit converts the signal from the transmit / receive frequency discriminator into a digital signal. A radar system characterized by the following features.
2. A radar system according to claim 1, The aforementioned transmitting and receiving device also includes a receiving channel discriminator. The aforementioned transmit / receive frequency discriminator outputs the combined received IF signal to the A / D conversion unit. The A / D conversion unit converts the combined received IF signal into a combined digital IF signal. The receiving channel discriminator divides the combined digital IF signal into digital IF signals for each antenna device. A radar system characterized by the following features.
3. A radar system according to claim 1, The aforementioned transmitting and receiving device comprises N A / D conversion units, The transmit / receive frequency discriminator discriminates the combined received IF signal into received IF signals from the N antenna frequency discriminators, and outputs each of these N received IF signals to the corresponding A / D converter. The N A / D conversion units output a digital IF signal for each of the antenna devices. A radar system characterized by the following features.
4. A radar system according to claim 1, The aforementioned transmitting and receiving device also includes an IF switch. The transmit / receive frequency discriminator discriminates the combined received IF signal into N received IF signals from the N antenna frequency discriminators and outputs these N received IF signals to the IF switch. The IF switch selects one received IF signal from N received IF signals and outputs it to the A / D conversion unit. The A / D conversion unit converts the input received IF signal into a digital IF signal. A radar system characterized by the following features.
5. A radar system according to any one of claims 1 to 4, The aforementioned transmitting and receiving device also includes a reference oscillator, The frequency conversion unit generates a signal from the signal generated by the reference oscillator to convert the received RF signal into a received IF signal. A radar system characterized by the following features.