JP4883922B2 - High frequency transmitter / receiver and radar apparatus including the same - Google Patents

Description

The present invention relates to a high-frequency transmitter / receiver used in a millimeter-wave radar module, a millimeter-wave wireless communication device, etc., and a part of a high-frequency signal for transmission leaks to the receiving side, and an intermediate frequency signal as noise corresponding thereto is RF transceiver having a switch capable of blocking the output to the receiving system and those related to the radar equipment comprising it.

  2. Description of the Related Art Conventionally, as a high frequency transmitter / receiver expected to be applied to a millimeter wave radar module, a millimeter wave wireless communication device, or the like, for example, one disclosed in Patent Document 1 is known.

  However, in such a high frequency transmitter / receiver, a part of the high frequency signal for transmission leaks to the receiving side in the intermediate frequency circuit of the high frequency transmitter / receiver, and an intermediate frequency signal as noise corresponding thereto is generated. There is a problem in that it is output as an unnecessary signal to the reception system, which adversely affects reception performance.

  The present inventor has already proposed a solution to this problem (see Patent Document 2). Examples of the configuration are shown in plan views in FIGS. 10 and 11, respectively. The basic configuration of the non-radiative dielectric line used in these configuration examples is as shown in a partially broken perspective view in FIG. 9, and the dielectric line 43 is parallel between the flat conductors 41 and 42. It is a sandwiched configuration.

  The high-frequency transmitter / receiver of the example shown in FIG. 10 is an example in which a transmitting antenna and a receiving antenna are integrated, and between parallel plate conductors 51 arranged at intervals of 1/2 or less of the wavelength of a millimeter wave signal. A millimeter-wave signal oscillating unit 52 attached to the first dielectric line 53 and frequency-modulating the millimeter-wave signal output from the high-frequency diode and propagating the first dielectric line 53 as a millimeter-wave signal; A pulse modulator (not shown) interposed in the middle of the dielectric line 53 and pulsed from the first dielectric line 53 as a millimeter wave signal for transmission and output from the first dielectric line 53, and a first dielectric A second dielectric line 58 is disposed close to the line 53 so that one end thereof is electromagnetically coupled, or one end is joined to the first dielectric line 53 to propagate a part of the millimeter wave signal to the mixer 59 side. And ferrite arranged parallel to the parallel plate conductor 51 And a first connection portion 54a, a second connection portion 54b, and a third connection portion 54c, which are arranged at predetermined intervals on the peripheral edge of each other and serve as input / output ends of millimeter wave signals, respectively. A circulator 54 for outputting a millimeter wave signal input from the other part from another connection part adjacent in the clockwise or counterclockwise direction within the plane of the ferrite plate, and outputting the millimeter wave signal of the first dielectric line 53 A circulator 54 having a first connecting portion 54a connected to the end thereof, and a third dielectric line connected to the second connecting portion 54b of the circulator 54 to propagate a millimeter wave signal and to have a transmitting / receiving antenna 56 at the tip portion. 55 and the third connecting portion 54c of the circulator 54, received by the transmitting / receiving antenna 56, propagated through the third dielectric line 55, and output from the third connecting portion 54c through the second connecting portion 54b. Propagated received wave to mixer 59 The dielectric line 57, the second dielectric line 58 and the fourth dielectric line 57 are brought close to each other or joined so as to be electromagnetically coupled, and a part of the millimeter wave signal is received. A high-frequency transmitter / receiver provided with a mixer 59 that mixes waves and generates an intermediate frequency signal. In this example, a switching control unit (not shown) that opens the output terminal when the pulse-modulated millimeter-wave signal for transmission is output from the pulse modulator is provided at the output terminal of the mixer 59. This prevents unnecessary signals from being output to the receiving system after the mixer 59 almost simultaneously with the input of the pulsed signal for starting the pulsed operation of the pulse modulator to the pulse modulator. Can do.

  The high-frequency transmitter / receiver of the example shown in FIG. 11 is an example in which the transmitting antenna and the receiving antenna are independent, and between the parallel plate conductors 61 arranged at intervals of 1/2 or less of the wavelength of the millimeter wave signal, A millimeter wave signal oscillating unit 62 attached to the first dielectric line 63 and frequency-modulating a high frequency signal output from the high frequency diode and propagating the first dielectric line 63 as a millimeter wave signal, and a first dielectric A pulse modulator (not shown) that is provided in the middle of the body line 63 to pulse the millimeter wave signal and output it from the first dielectric line 63 as a millimeter wave signal for transmission, and the first dielectric line 63 A second dielectric line 68 that is disposed in close proximity so that one end side is electromagnetically coupled to the first dielectric line 63, and one end is joined to the first dielectric line 63 to propagate a part of the millimeter wave signal to the mixer 71 side; Ferrite plate arranged parallel to the parallel plate conductor 61 A first connecting portion 64a, a second connecting portion 64b, and a third connecting portion 64c, which are arranged at predetermined intervals on the peripheral edge and are respectively input / output ends of millimeter wave signals, Is a circulator 64 that outputs a millimeter wave signal input from the other connection portion clockwise or counterclockwise in the plane of the ferrite plate, and is an output end of the millimeter wave signal of the first dielectric line 63 Are connected to a circulator 64 to which the first connection portion 64a is connected, and a third dielectric line 65 which is connected to the second connection portion 64b of the circulator 64 and propagates a millimeter wave signal and has a transmission antenna 66 at the tip. And a millimeter wave which is connected to the fourth dielectric line 69 provided with the receiving antenna 70 at the front end and the mixer 71 at the other end, and the third connecting portion 64c of the circulator 64, and received by the transmitting antenna 66. Non-reflective termination 67a that attenuates the signal The fifth dielectric line 67 provided at the tip, the middle of the second dielectric line 68 and the middle of the fourth dielectric line 69 are brought close to each other or joined so as to be electromagnetically coupled. This is a high-frequency transmitter / receiver provided with a mixer 71 that mixes a part of a wave signal and a received wave to generate an intermediate frequency signal. In this example, the output end of the mixer 71 is provided with a switching control unit (not shown) that opens the output end when a pulse-modulated millimeter-wave signal for transmission is output from the pulse modulator. Thus, almost simultaneously with the input of the pulsed signal for starting the pulsed operation of the pulse modulator to the pulse modulator, the unnecessary signal mixed directly from the transmitting antenna 66 to the receiving antenna 70 is placed after the mixer 71. Can be prevented from being output to the receiving system.

  Next, FIG. 8 is a block circuit diagram showing the configuration of each part when the high-frequency transceiver shown in FIG. 10 is used as a millimeter wave radar.

  In FIG. 8, reference numeral 111 denotes a VCO (Voltage Controlled Oscillator) having a Gunn diode and a varactor diode, and operates by inputting a signal to the IN-2 terminal for inputting the modulation signal. The output signal of the VCO 111 is pulse modulated by the pulse modulator 112 by inputting the pulsed signal input to the IN-1 terminal to the pulse modulator 112. The pulse modulator 112 is interposed in the middle of the first dielectric line 53 in FIG. 10, and is a switch (RF switch) whose configuration is shown in a perspective view in FIG.

  In the configuration of the pulse modulator shown in FIG. 12, a choke-type bias supply line 90 is formed on one main surface of the wiring board 88, and solder-mounted between connection electrodes 81 and 81 formed in the middle thereof. This is a switch provided with a beam lead type PIN diode or a Schottky barrier diode 80. Such a switch is installed between the end face of the first dielectric line 53 so that the PIN applied voltage or the Schottky barrier diode 80 is in the horizontal direction. used.

  113 is a circulator that transmits a millimeter wave signal to the antenna 114 side during transmission and a reception wave is transmitted to the mixer 115 side during reception, 114 is an antenna for transmitting and receiving millimeter wave signals, and the antenna 114 is the circulator 113 For example, a horn antenna or the like connected to a metal waveguide or a dielectric waveguide filled with a dielectric to the metal waveguide. Reference numeral 115 denotes a mixer that outputs an intermediate frequency signal for detecting a distance to the target and the like by mixing the millimeter wave signal output from the VCO 111 and the reception signal received by the antenna 114.

  Reference numeral 116 denotes a switch as a switch for blocking or passing the intermediate frequency signal output from the mixer 115. Reference numeral 119 denotes a controller that controls the opening / closing (on-off) timing of the switch 116. The switch 116 and the control unit 119 constitute a switching control unit.

  The control unit 119 receives the pulsed signal of the IN-1 terminal so as to be interlocked with the pulse modulator 112, and the transmission millimeter wave signal pulse-modulated by the pulse modulator 112 is converted into the NRD guide and the dielectric conductor. The switching timing is such that the signal is reflected by the connection with the wave tube or leaked from the circulator 113 and output as an unnecessary signal via the mixer 115 to be input to the amplifier 118 before being cut off by the switch 116. To control.

  Reference numeral 117 denotes a capacitor for AC coupling between the switch 116 and the amplifier 118.

  In the high-frequency transmitter / receiver shown in FIG. 10, an example is shown in which a circulator 54 is used as a component for configuring a transmission / reception integrated antenna. As an alternative to such a circulator 54, a rat race type hybrid ( For example, it is widely known that there is a branch line type hybrid (for example, see Patent Document 5).

  With the above configuration, the pulse-modulated millimeter-wave signal for transmission can be blocked so that it does not leak into the mixer 115 and leak to the receiving system at the subsequent stage, so that the detection accuracy of the millimeter-wave radar system can be improved.

Patent Document 3 also discloses an example in which a transmission / reception changeover switch is connected to a VCO in the above-described high-frequency transceiver. In such an example, the millimeter wave signal generated by the VCO is switched by the transmission / reception selector switch to output it as a transmission millimeter wave signal to the transmission side or as a local signal to the reception side, and similarly pulsed. The transmitted millimeter wave signal can be output for transmission.
JP 2000-258525 A JP 2003-198421 JP 2001-264426 A Japanese Patent Laid-Open No. 2002-100910 JP 2003-179414 A

  However, even in the configuration proposed in Patent Document 2, as a result of repeated studies by the present inventors to further improve the performance of the high-frequency transmitter / receiver, the following problems have been found that further improvement is desired.

  First, as one of such problems, it is necessary to precisely control at least the closing (ON) timing of the switch 116.

  In general, the pulse modulator 112 using a high-frequency diode has characteristics unique to the high-frequency diode such as a zero-bias capacity. Therefore, even if an ideal pulse signal for driving is input, ringing noise is generated in the modulation current. Such distortion may occur to a greater or lesser extent. Also, the drive pulse signal itself may have the same or more similar distortion. For these reasons, a certain period of time is required until the output intensity of the millimeter wave signal output from the pulse modulator 112 is stabilized in a steady state within one period of the signal. As a result, when the signal of the IN-1 terminal is opened (off), the output of the millimeter wave signal is opened (off), and then the switch 116 is closed (on), depending on the timing, There is a problem that the fluctuation of the output intensity of the millimeter wave signal remains and is output to the mixer 115 as an unnecessary signal (noise), which may interfere with the signal to be detected and deteriorate the radar detection performance. There was a point.

  The present invention has been devised to solve the above-described problems that are desired to be improved. The purpose of the present invention is to cause a part of the high-frequency signal for transmission to leak to the receiving side, and to switch the high-frequency signal for transmission. In a high-frequency transmitter / receiver having a switch capable of blocking the output of an intermediate frequency signal as noise caused by, for example, noise to the receiving system, even in a transient state where the high-frequency signal for transmission is switched, An object of the present invention is to provide a high frequency transmitter / receiver capable of reliably blocking an intermediate frequency signal.

Another object of the present invention is to provide a high-performance radar equipment using a high frequency transceiver of the present invention.

The high-frequency transmitter / receiver of the present invention outputs a high-frequency oscillator that generates a high-frequency signal, and the high-frequency signal that is input from an input end connected to the high-frequency oscillator, from one output end as a transmission high-frequency signal, Alternatively, a changeover switch for switching whether to output a local signal from the other output end, and an input end connected to the one output end of the changeover switch, an output end, and the input end or the output end are switched and connected. A second changeover switch having an input / output end; a transmission / reception antenna connected to the input / output end of the second changeover switch; the other output end of the changeover switch; and the second changeover switch Connected between the output ends, the local signal output to the other output end, and the high frequency received by the transmitting / receiving antenna A mixer that mixes signals and outputs an intermediate frequency signal, and is connected to the output end of the mixer, shuts off the intermediate frequency signal in an open state, and stabilizes the high frequency signal for transmission in a non-output state A switch that is in a closed state and passes the intermediate frequency signal; and a filter that is connected to the switch, removes switching noise when the switch is opened and closed, and passes the intermediate frequency signal. And a function of performing a self-diagnosis by inputting a test signal having a frequency lower than the 3 dB cutoff frequency of the filter between the output terminal of the mixer and the switch.

High-frequency transceiver of the present invention includes a high frequency oscillator for generating a high-frequency signal, or outputs the high frequency signal input from an input terminal connected to said high-frequency oscillator, from one output terminal as the transmission high-frequency signal , or is connected to the changeover switch switches whether to output from the other output terminal as a local signal, a transmitting antenna connected to the one output end of the changeover switch, the other output terminal side of the changeover switch Connected to the other output terminal of the change-over switch and the receiving antenna, and a local signal output from the other output terminal and a high-frequency signal received by the receiving antenna are mixed. Connected to an output terminal of the mixer, and the intermediate frequency signal in an open state. A switch that shuts off and closes when the high frequency signal for transmission is stable in a non-output state and passes the intermediate frequency signal; and a switch that is connected to the switch and that is switched when the switch is opened and closed A filter that removes noise and passes the intermediate frequency signal, and inputs a test signal having a frequency lower than the 3 dB cutoff frequency of the filter between the output terminal of the mixer and the switch. And has a self-diagnosis function .

The radar apparatus according to the present invention includes a high-frequency transmitter / receiver according to any one of the first to second aspects of the present invention, and distance information to a detection target by processing the intermediate frequency signal output from the high-frequency transmitter / receiver. A distance information detector for detecting.

According to the high frequency transmitter / receiver of the present invention, a high frequency oscillator that generates a high frequency signal, and the high frequency signal input from an input end connected to the high frequency oscillator is output from one output end as a high frequency signal for transmission. Or a changeover switch for switching whether to output from the other output end as a local signal, an input end connected to the one output end of the changeover switch, an output end, and the input end or the output end. A second changeover switch having an input / output terminal to be connected; a transmission / reception antenna connected to the input / output end of the second changeover switch; the other output end of the changeover switch; and the second changeover switch Is connected between the output terminals of the other, and the local signal output to the other output terminal is received by the transmitting / receiving antenna. A mixer that mixes frequency signals and outputs an intermediate frequency signal, and is connected to the output terminal of the mixer, and when the intermediate frequency signal is cut off in an open state and the high frequency signal for transmission is stabilized in a non-output state A switch that is closed to pass the intermediate frequency signal, and a filter that is connected to the switch, removes switching noise when the switch is opened and closed, and passes the intermediate frequency signal; When the transmission high-frequency signal is intermittently transmitted when the high-frequency signal is switched between the transmission high-frequency signal and the local signal by the changeover switch, the switch is used when the strength of the transmission high-frequency signal is unstable. Is in an open (off) state so as to cut off the intermediate frequency signal, and the open / close signal input to the changeover switch includes noise such as pulse waveform distortion. Even if noise is mixed in the transmission high-frequency signal and a part of the transmission high-frequency signal including such noise leaks to the mixer side, the switch Since it works to cut off the intermediate frequency signal corresponding to a part appropriately, the S / N (signal-to-noise) ratio can be increased, and a high-frequency transmitter / receiver that can improve the reception performance is obtained.

According to the high frequency transceiver of the present invention, the output and the high-frequency oscillator for generating a high-frequency signal, the high frequency signal input from an input terminal connected to said high-frequency oscillator, from one output terminal as the transmission high-frequency signal either, or a change-over switch switching between the output from the other output terminal as a local signal, a transmitting antenna connected to the one output end of the changeover switch, the other output terminal side of the changeover switch Connected between the connected receiving antenna, the other output end of the changeover switch and the receiving antenna, and a local signal output from the other output end and a high frequency signal received by the receiving antenna Are connected to the output end of the mixer, and in the open state, the intermediate frequency is output. A switch that shuts off the signal and is closed when the high frequency signal for transmission is stable in a non-output state and passes the intermediate frequency signal, and is connected to the switch, and when the switch is opened and closed And a filter that allows the intermediate frequency signal to pass therethrough, so that the high-frequency signal is switched between the high-frequency signal for transmission and the local signal by a changeover switch, and the high-frequency signal for transmission is intermittently transmitted. When the intensity of the high frequency signal for transmission is unstable, the switch is opened (off) so as to cut off the intermediate frequency signal. Noise is included, this noise is mixed in the high-frequency signal for transmission, and a part of the high-frequency signal for transmission containing such noise leaks to the mixer side. Even so, the switch works to properly cut off the intermediate frequency signal corresponding to a part of the high frequency signal for transmission including such noise, so that the S / N (signal to noise) ratio is increased. Therefore, a high-frequency transmitter / receiver capable of improving reception performance can be obtained.

Further, according to the radar apparatus of the present invention, the distance information detection for detecting the distance information to the high-frequency transceiver and, detection object by processing the intermediate frequency signal output from the RF transceiver of the present invention Since the reception performance of the high-frequency transmitter / receiver is high, the radar apparatus can detect a detection object quickly and surely, and can also detect a detection object at a short distance or a distant place. .

For high-frequency transceiver and a radar apparatus using thereof of the present invention will be described in detail below. In the following description, “first and second high-frequency transceivers of the present invention” are both reference examples.

  1 to 4 are block circuit diagrams schematically showing examples of the first to fourth high-frequency transceivers according to the present invention. FIG. 5 is a block circuit diagram schematically showing another example of the embodiment of the third high-frequency transceiver of the present invention. FIG. 6 is a block circuit diagram schematically showing another example of the fourth high frequency transceiver according to the present invention. FIG. 7 is a plan view schematically showing an example of a high-frequency transmission unit of the high-frequency transceiver shown in FIG.

  1 to 7, 1 is a high-frequency oscillator, 2 is a branching device, 2a, 2b, and 2c are input terminals, one output terminal, the other output terminal, 3, 3 ', and 3 "are switches, respectively. Switch, RF switch as second switch, first RF switch, second RF switch, 4 is hybrid, 4a, 4b, 4c are first terminal, second terminal, third terminal, 5 are Transmission / reception antenna, 6 is a mixer, 7 is an IF switch as a switch, 8 is an RF switch as a changeover switch, 8a is an input end, 8b is one output end, 8c is the other output end, 9 is a transmission antenna, 10 Is a receiving antenna, and 11 is a lower flat conductor (the upper flat conductor is not shown).

  An example of an embodiment of the first high-frequency transmitter / receiver of the present invention shown in FIG. 1 is a high-frequency oscillator 1 that generates a high-frequency signal, and the high-frequency signal that is connected to the high-frequency oscillator 1 is branched to one output. A branching device 2 that outputs to an end 2b and the other output end 2c, and first, second, and third terminals 4a, 4b, and 4c, and the first terminal 4a is connected to one output end 2b. The hybrid 4 that passes a high-frequency signal from the first terminal 4a to the second terminal 4b as a transmission high-frequency signal RFt and passes the high-frequency signal from the second terminal 4b to the third terminal 4c, and the hybrid 4 The transmitting / receiving antenna 5 connected to the second terminal 4b is connected between the high-frequency oscillator 1 and the branching device 2 or between the branching device 2 and the hybrid 4 (in this example, between the branching device 2 and the hybrid 4). High-frequency signal RFt for transmission The RF switch 3 that is passed intermittently, the high-frequency signal branched to the other output end 2c and the transmitting / receiving antenna connected between the other output end 2c of the branching device 2 and the third terminal 4c of the hybrid 4 The mixer 6 that outputs the intermediate frequency signal by mixing the high frequency signal received at 5 and the intermediate frequency signal that is connected to the output terminal of the mixer 6 in the open state is cut off and the transmission high frequency signal RFt is not output. And an IF switch 7 that is in a closed state and allows an intermediate frequency signal to pass through when the state is stabilized.

  In addition, the second embodiment of the second high-frequency transmitter / receiver of the present invention shown in FIG. 2 includes a high-frequency oscillator 1 that generates a high-frequency signal and a high-frequency signal that is connected to the high-frequency oscillator 1 for branching. A branching device 2 that outputs to the output terminal 2b and the other output terminal 2c, a transmitting antenna 9 connected to one output terminal 2b, and a receiving antenna 10 connected to the other output terminal 2c side of the branching device 2 The transmission high-frequency signal RFt connected between the high-frequency oscillator 1 and the branching device 2 or between the branching device 2 and the transmission antenna 9 (between the branching device 2 and the transmission antenna 9 in this example) is intermittently supplied. An RF switch 3 to be passed through, a high-frequency signal branched between the other output end 2c connected between the other output end 2c of the branching device 2 and the receiving antenna 10, and a high-frequency signal received by the receiving antenna 10 are connected. Mixing and outputting an intermediate frequency signal The intermediate frequency signal connected to the output terminal of the circuit 6 and the mixer 6 is cut off in the open state, and when the high frequency signal RFt for transmission is stabilized in the non-output state, the intermediate frequency signal is closed to pass through. In this configuration, an IF switch 7 is provided.

  In the above configuration, the IF switch 7 is opened before and after the transmission high-frequency signal RFt is intermittently transmitted, and when the output state of the transmission high-frequency signal RFt is unstable, the IF switch 7 is opened to cut off the intermediate frequency signal. After the output state is stabilized, the closed state is entered to operate the intermediate frequency signal. In order to operate the IF switch 7 as described above, specifically, a switching control unit (not shown) for controlling the opening and closing of the IF switch 7 is provided with a delay line or a delay circuit element, and the switching signal of the RF switch 3 is provided. It is sufficient to generate a signal for controlling the opening / closing of the IF switch 7 in the switching control unit at a timing delayed by a certain time. The IF switch 7 is specifically a semiconductor logic device such as CMOS or TTL, an analog IC, a bipolar transistor, a field effect transistor (FET), a mechanical switch, a MEMS (micro electro mechanical systems) switch, or the like. May be used.

  The RF switch 3 may be a switch made of a semiconductor element such as a gallium arsenide (GaAs) field effect transistor (MESFET) or a gallium arsenide (GaAs) PIN diode. The RF switch 3 is either one of a high-frequency transmission line for transmitting a high-frequency signal connected between the high-frequency oscillator 1 and the branching device 2 and between the branching device 2 and the hybrid 4 or the transmission antenna 9. Insert it in the middle. In this case, when a TEM transmission line such as a microstrip line or a coplanar line is used as the high-frequency transmission line, the RF switch 3 is connected in series with the strip conductor (a signal line separated from the ground conductor by a certain distance). Just connect. When a waveguide or a non-radiative dielectric line is used as the high-frequency transmission line, a PIN diode similar to that shown in FIG. 12 is provided in the middle of the dielectric line constituting the waveguide or the non-radiative dielectric line. Or the like may be provided so that the direction of the current flowing through the PIN diode or the like is parallel to the direction of the electric field of the high-frequency signal transmitted to the high-frequency transmission line.

  Note that such an RF switch 3 using a nonradiative dielectric line or the like allows a high frequency signal to pass by applying either a forward bias voltage, a non-bias voltage or a reverse bias voltage to a PIN diode or the like. Needless to say, it can be reflected.

  Further, between the high-frequency oscillator 1 and the RF switch 3 (preferably on the input end 2a side of the branching device 2), when the RF switch 3 is turned off, it is reflected by the RF switch 3 and returned to the high-frequency oscillator 1. It is preferable to provide an isolator for suppressing high-frequency signals.

  The first and second high-frequency transmitter / receiver embodiments of the present invention shown in the block circuit diagrams of FIGS. 1 and 2 have the above-described configuration, so that the transmission high-frequency signal RFt is intermittently transmitted. Furthermore, since the IF switch 7 is in an open (off) state so as to cut off the intermediate frequency signal when the intensity of the high frequency signal RFt for transmission is unstable, the pulse waveform distortion is applied to the switching control signal input to the RF switch 3. If the noise is mixed into the transmission high-frequency signal RFt and a part of the transmission high-frequency signal RFt containing such noise leaks to the mixer 6 side, the IF switch 7 However, since it works so as to appropriately cut off the intermediate frequency signal corresponding to a part of the high frequency signal RFt for transmission containing such noise, the S / N (signal to noise) ratio can be increased and the reception can be performed. High performance It can be.

  Further, in the first and second embodiments of the first and second high-frequency transceivers of the present invention, it is preferable to configure as follows.

  The IF switch 7 is preferably in an open state after being closed and before the next transmission high-frequency signal RFt is output from the RF switch 3. To do this, the switching control unit may be provided with a similar delay line or delay circuit element in addition to the delay line or delay circuit element, or another switching control signal may be input. . Thereby, before the next intermediate frequency signal is output, the pulsed transmission high frequency signal including noise is mixed into the mixer 6 and the intermediate frequency signal including noise is connected to the receiving system connected to the subsequent stage of the mixer 6. Since the signal can be satisfactorily blocked by the IF switch 7 so as not to leak, the S / N ratio can be further increased, that is, the reception performance can be increased.

  The RF switch 3 may be a semiconductor element made of a material containing a III-V group compound semiconductor as a main component. In addition to gallium arsenide (GaAs), indium / phosphorus (InP) and indium / antimony (InSb), materials containing III-V compound semiconductors include indium (In) or aluminum (Al) in gallium arsenide (GaAs). Indium gallium arsenide (InGaAs), gallium arsenide aluminum (GaAlAs), indium arsenide gallium aluminum (InGaAlAs) or indium arsenide aluminum gallium (InAlGaAs), or indium arsenide (InAs), aluminum arsenide ( A mixed crystal of AlAs) and indium aluminum arsenide (InAlAs) or a multilayer superlattice (MQW) may be used. Further, a diode, a bipolar transistor, or a field effect transistor (FET) may be used as a semiconductor element made of any of these materials. In this case, since a semiconductor element made of a material containing such a III-V group compound semiconductor has a high carrier mobility and a short lifetime, when the RF switch 3 supplies a modulation current to the semiconductor element, Since the modulation current of the RF switch 3 can be quickly converged from the transient state to the steady state, the pulsed transmission high-frequency signal corresponding to the modulation current can be quickly converged to the steady state. After the output high-frequency signal for transmission is output, even if the IF switch 7 is closed (turned on) at an early timing, an intermediate frequency signal in which an unnecessary signal generated immediately after the rise of the pulse is mixed with the high-frequency signal for transmission No time is output to the subsequent stage of the mixer 6, and the time when the intermediate frequency signal cannot be transmitted / received by cutting off the intermediate frequency signal is shortened. Door can be.

  If high speed is not particularly required for the operation of the RF switch 3, silicon (Si), silicon-germanium (SiGe) mixed crystal or the like may be used in addition to the III-V group compound semiconductor.

  A filter that prevents noise added to the intermediate frequency signal when the IF switch 7 is opened and closed and allows the intermediate frequency signal to pass therethrough is provided at the subsequent stage of the IF switch 7. At this time, switching noise, which is generated when the IF switch 7 opens and closes and is added to the intermediate frequency signal, can be removed by a subsequent filter, so that unnecessary noise signals are transferred to other surrounding circuit systems. Mixing can be reliably suppressed. Further, since unnecessary noise signals are removed by the filter, the intermediate frequency signal to be received can be easily and reliably identified.

  In this case, when a test signal having a frequency lower than the 3 dB cutoff frequency of the filter is input between the output terminal of the mixer 6 and the IF switch 7, the test signal is higher than the intermediate frequency signal. Since the frequency is low and the noise added to the intermediate frequency signal when the IF switch 7 is opened and closed is higher than the intermediate frequency signal, the noise passes through the IF switch 7 separately from the intermediate frequency signal and noise and is output without being removed by the filter. By confirming that the test signal is output through the IF switch 7 and the filter, it is possible to easily provide an effective self-diagnosis function in the high-frequency transmitter / receiver without affecting the switching noise elimination. be able to.

  In addition, a test opening / closing signal for generating switching noise may be input to the IF switch 7 and a switching noise detection terminal may be provided between the IF switch 7 and the filter. At this time, since the test switch signal is inputted, the IF switch 7 generates weak switching noise. Therefore, even if the test signal is not attenuated again by an attenuator or the like, the switching noise is attenuated. Used as a test signal, input to a subsequent circuit, and detected by a detection terminal provided between the IF switch 7 and the filter without saturating an active circuit such as an amplifier connected to the subsequent circuit. Therefore, a self-diagnosis function can be easily provided.

  In addition, in such a configuration, a signal switching switch (for example, a switching described later) that switches and inputs a DC signal separately from the switching control signal to the input unit that inputs, for example, a pulse switching control signal to the RF switch 3. An RF switch 8 or the like may be provided. As such a signal switching switch, for example, a CMOS semiconductor switch having a function called SPDT or a switch that can switch between two systems in the same type as the IF switch 7 may be used. At this time, the signal switching switch operates to switch the signal path of the input signal used in the RF switch 3 separately from the input of the switching control signal to the RF switch 3, so that the operation test signal As a source, for example, a direct current signal generated by a direct current power source can be input to the RF switch 3, so that not only a pulsed switching control signal can be input to the RF switch 3, but also the transmission system of this high frequency transceiver. For the operation test, a DC signal such as a DC voltage can be input, and the output of the RF switch 3 corresponding to the signal is output to the subsequent transmission circuit, so that the operation test (failure diagnosis) of the transmission circuit is performed. It is also possible to provide a fault diagnosis function of the transmission circuit.

  In this case, a capacitor may be connected in parallel with the signal switching switch. At this time, this capacitor cancels out the parasitic capacitance (parasitic capacitance) existing inside the signal switching switch, and the high frequency of the pulsed switching control signal in the signal switching switch generated by the parasitic capacitance of the signal switching switch Since it works to reduce the reflection of components, a switching control signal with less distortion can be input to the RF switch 3. Further, since the signal level of, for example, a pulsed transmission high-frequency signal transmitted from the RF switch 3 is stabilized, a part of the transmission high-frequency signal is blocked from being mixed into the mixer 6 and leaking to the receiving system at the subsequent stage. Even if the IF switch 7 is closed (turned on) immediately after the transmission high-frequency signal is transmitted, an unnecessary intermediate frequency signal is not output, and reception can be performed immediately after the transmission high-frequency signal is transmitted. it can.

  Next, an example of the third high-frequency transmitter / receiver according to the present invention shown in FIG. 3 includes a high-frequency oscillator 1 that generates a high-frequency signal, and one of the high-frequency signals connected to the high-frequency oscillator 1 by switching. A switching RF switch 8 'that outputs as a transmission high-frequency signal RFt to the output terminal 2b or as a local signal LO to the other output terminal 2c, an input terminal 8 "b, an output terminal 8" c, and an input / output terminal 8 " a second switching RF having an input terminal 8 ″ b connected to one output terminal 8′b and switching the input / output terminal 8 ″ a to the input terminal 8 ″ b or the output terminal 8 ″ c. The switch 8 ″, the transmitting / receiving antenna 5 connected to the input / output terminal 8 ″ a of the second switching RF switch 8 ″, the other output terminal 8′c of the switching RF switch 8 ′, and the second switching RF switch Connected to the output 8 ″ c of 8 ″ The mixer 6 that mixes the local signal LO output to the other output end 8′c and the high-frequency signal received by the transmitting / receiving antenna 5 to output an intermediate frequency signal, and is connected to the output end of the mixer 6; The configuration includes an IF switch 7 that shuts off the intermediate frequency signal in the open state and closes when the transmission high frequency signal RFt is stable in the non-output state and passes the intermediate frequency signal.

  An example of the embodiment of the fourth high-frequency transmitter / receiver of the present invention shown in FIG. 4 is a high-frequency oscillator 1 that generates a high-frequency signal, and one output that switches the high-frequency signal connected to the high-frequency oscillator 1. A switching RF switch 8 that outputs as a transmission high-frequency signal to the terminal 8b or a local signal LO to the other output terminal 8c, a transmission antenna 9 connected to one output terminal 8b, and the other of the switching RF switch 8 The reception antenna 10 connected to the output terminal 8c side of the signal, and the local signal LO output to the other output terminal 8c connected between the other output terminal 8c of the switching RF switch 8 and the reception antenna 10 and reception. A mixer 6 that mixes the high-frequency signal received by the antenna 10 and outputs an intermediate frequency signal, and is connected to the output end of the mixer 6 and cuts off the intermediate frequency signal in the open state and transmits it. When the high frequency signal RFt is stabilized in the non-output state, the IF switch 7 is provided which is in a closed state and passes the intermediate frequency signal.

  In the above configuration, the changeover RF switches 8, 8 ′ and the second changeover switch 8 ″ are made of semiconductor elements such as a gallium arsenide (GaAs) field effect transistor (MESFET) and a gallium arsenide (GaAs) PIN diode. A so-called SPDT (Single Port Double Throw) switch may be used, and the input terminals 8a and 8'a of such switching RF switches 8 and 8 'are connected to the high-frequency oscillator 1 to switch the switching RF switches 8 and 8'. Thus, the high-frequency signal generated by the high-frequency oscillator 1 is output as the transmission high-frequency signal RFt to one of the output terminals 8b and 8'b or as the local signal LO to the other output terminals 8c and 8'c. do it.

  Such a switching RF switch 8, 8 ′ completely cuts off the transmission high-frequency signal RFt at the moment when the output is switched from the transmission high-frequency signal RFt to the local signal LO, and is connected to one of the output terminals 8b, 8′b. Ideally, noise should not be generated, but in reality, because of the distortion of the switching control signal input to the switching RF switches 8 and 8 'and the switching characteristics of the switching RF switches 8 and 8' themselves, After the output is switched from the high-frequency signal RFt to the local signal LO, noise at the time of switching is output to one of the output terminals 8b and 8'b, and it takes a certain time until it is sufficiently attenuated. When such noise leaks to the mixer 6, an unnecessary intermediate frequency signal as noise is output from the mixer 6. Therefore, it is effective to use the IF switch 7 in the third and fourth high-frequency transceivers of the present invention as in the case of the first and second high-frequency transceivers of the present invention.

  That is, in the above configuration, before and after the transmission high-frequency signal RFt is intermittently transmitted, the IF switch 7 is opened when the output state of the transmission high-frequency signal RFt is unstable, and interrupts the intermediate frequency signal. Then, after the output state is stabilized, the closed state is set and the intermediate frequency signal is allowed to pass. In order to operate the IF switch 7 as described above, specifically, a switching control unit (not shown) for controlling the opening and closing of the IF switch 7 is provided with a delay line or a delay circuit element, and the switching signal of the RF switch 3 is provided. It is sufficient to generate a signal for controlling the opening / closing of the IF switch 7 in the switching control unit at a timing delayed by a certain time. The IF switch 7 is specifically a semiconductor logic device such as CMOS or TTL, an analog IC, a bipolar transistor, a field effect transistor (FET), a mechanical switch, a MEMS (micro electro mechanical systems) switch, or the like. May be used.

  According to the third and fourth high-frequency transceivers of the present invention, since the above-described configuration is adopted, the high-frequency signal is switched between the transmission high-frequency signal RFt and the local signal LO by the switching RF switch 8 ′ (switching RF switch 8). When the transmission high-frequency signal RFt is intermittently transmitted, the IF switch 7 is opened (off) so as to cut off the intermediate frequency signal when the strength of the transmission high-frequency signal RFt is unstable. The open / close signal input to the RF switch 8 ′ (switching RF switch 8) includes noise such as pulse waveform distortion. This noise is mixed in the transmission high-frequency signal RFt, and further includes such noise. Even if a part of the trusted high-frequency signal RFt leaks to the mixer 6 side, the IF switch 7 appropriately applies the intermediate frequency signal corresponding to a part of the transmission high-frequency signal RFt including such noise. Since act to shut off, it is possible to increase the S / N (signal to noise) ratio, it is possible to increase the reception performance.

  Also in the third and fourth high-frequency transmitter / receivers of the present invention, the switching RF switch 8 '(switching RF switch 8) may be a semiconductor element made of a material containing a III-V group compound semiconductor. This is because the time during which transmission / reception cannot be performed can be reduced in the same manner as described above.

  Next, other examples of the third and fourth high-frequency transmitter / receivers according to the present invention shown in the block circuit diagrams in FIGS. 5 and 6 are shown in FIG. 3 and FIG. The switching RF switch 8 '(switching RF switch 8) branches the input high-frequency signal and outputs it to one output terminal 2b and the other output terminal 2c with respect to the high-frequency transceiver shown in the block circuit diagram. Device 2 and first and second PIN diodes 3 ', 3 "connected to one output terminal 2b and the other output terminal 2c, respectively, and these first and second PIN diodes 3 are provided. A bias circuit (not shown) for applying a forward bias voltage is connected to at least one of ', 3'.

  In addition, the high-frequency transmission part of such a high-frequency transmitter / receiver is not a high-frequency transmission line for connecting the components as shown in the plan view of FIG. 7 in the case of the high-frequency transmitter / receiver shown in FIG. When a substrate on which a PIN diode similar to that shown in FIG. 12 is mounted as an RF switch 3 ', 3 "is inserted in the middle of the radiation dielectric line, the non-radiative dielectric line and the RF switch 3', 3" are Since the loss of high-frequency passage is small, it is advantageous in that high transmission / reception performance can be obtained for, for example, a millimeter wave signal having a frequency of about 76 GHz.

  According to another example of the third and fourth high-frequency transceiver embodiments of the present invention shown in block circuit diagrams in FIGS. 5 and 6, respectively, the same as the high-frequency transceiver shown in FIGS. 3 and 4 above. In addition, since at least one of the first and second PIN diodes 3 ′ and 3 ″ has a low impedance, even if the first and second PIN diodes 3 ′ and 3 ″ are switched, a high frequency is obtained. Since the impedance viewed from the signal input side (high frequency oscillator 1 side) can be always low and stable, load fluctuations of the high frequency oscillator 1 can be suppressed without using an isolator or the like, and the oscillation frequency of the high frequency signal can be stabilized. There are advantages that can be done.

  Further, in such a configuration, there is a time zone in which the local signal LO is input to the mixer 6 at the same time as the transmission high-frequency signal RFt is transmitted, so that a part of the transmission high-frequency signal RFt is in that time zone. An intermediate frequency signal as noise due to leakage to the mixer 6 may be generated. Since the intermediate frequency signal as such noise is blocked by the IF switch 7, the transmission frequency is stabilized as a whole. And the reception S / N (signal to noise) ratio can be increased.

  Next, in the first to fourth high-frequency transmitter / receivers of the present invention, each component may be configured in detail as follows in addition to the above.

The material of the dielectric line, which is a component of the non-radiative dielectric line, includes resins such as tetrafluoroethylene and polystyrene, or cordierite (2MgO · 2Al ₂ O ₃ · 5SiO ₂ ) ceramics having a low relative dielectric constant, Ceramics such as alumina (Al ₂ O ₃ ) ceramics and glass ceramics are preferable, and these have low loss in the millimeter wave band. In addition, although the cross-sectional shape of the dielectric line is basically rectangular, it may be rounded at the corners of the rectangle, and various cross-sectional shapes used for millimeter wave signal transmission are used. can do.

  The material of the flat conductor 11 is Cu, Al, Fe, Ag, Au, Pt, SUS (stainless steel), brass (Cu-Zn alloy), etc. in terms of high electrical conductivity and good workability. The conductor plate is suitable. Or what formed these conductor layers on the surface of the insulating board which consists of ceramics, resin, etc. may be used.

  In addition, the substrate 88 is made of aluminum (Al), gold (Au), copper (Cu), etc. on one main surface of a plate-like substrate made of tetrafluoroethylene, polystyrene, glass ceramics, glass epoxy resin, epoxy resin or the like. A choke-type bias supply line 90 formed of a strip conductor or the like made of is used.

  In addition to non-radiative dielectric lines, waveguides, dielectric waveguides, dielectric waveguide lines, strip lines can be used as high-frequency transmission lines for connecting high-frequency signals by connecting circuit elements. A high-frequency transmission line such as a microstrip line, a coplanar line, a slot line, or a coaxial line may be selected and used according to the frequency band to be used and the application. In addition to the millimeter wave band, the frequency band to be used is effective even in the microwave band or lower frequency band.

  Next, a radar apparatus using the high-frequency transmitter / receiver of the present invention, a radar apparatus-equipped vehicle equipped with the radar apparatus, and a radar apparatus-equipped small ship will be described.

  An example of an embodiment of a radar apparatus according to the present invention includes a high-frequency transmitter / receiver according to any one of the first to fourth aspects of the present invention described above, and an intermediate frequency signal output from the high-frequency transmitter / receiver. And a distance information detector for detecting the distance information.

  In the above configuration, the distance information detector performs signal processing on the detected intermediate frequency signal and outputs distance information including the distance and direction from the radar device to the detection target. For example, the distance information detector includes an arithmetic circuit including a differentiation circuit, an integration circuit, a square circuit, and the like that calculate an intermediate frequency signal as position information, a determination circuit that determines an output of the arithmetic circuit, these arithmetic circuits, And a computer that operates the discriminating circuit and the high-frequency transceiver according to a series of sequences. A circuit in which an operational amplifier (op amp), a comparator, or the like is combined may be used for the arithmetic circuit and the discrimination circuit. Further, a switch, an amplifier, a filter, or the like may be used as necessary. Also, in the process of these calculations and discrimination, analog signals are converted into digital signals at once, these calculations and discrimination are processed with digital signals, and digital signals are converted into analog signals as needed. And a DA converter may be used. At this time, for example, a digital signal processor (DSP) that performs fast Fourier transform (FFT) or the like may be used as the arithmetic circuit that calculates the digital signal after A / D conversion.

  According to such an example of the embodiment of the radar apparatus of the present invention, any one of the first to fourth high-frequency transmitters / receivers of the present invention is used as a high-frequency transmitter / receiver that is a component, and the reception performance thereof is Since it is high, it is possible to detect a detection object quickly and reliably, and also to detect a detection object at a close distance or a distant place. In addition to the radar device, the high-frequency transmitter / receiver of the present invention is, for example, a so-called physical medium that is a physical layer (physical layer) of a wireless device used in, for example, a wireless LAN. -Configuration as a de-pendant (PMD) device, consisting of this PMD device and its higher-layer physical media attachment (PMA) device, media access controller (MAC) device, and other devices As a wireless device.

A radar apparatus- equipped vehicle equipped with the radar apparatus of the present invention includes the radar apparatus of the present invention, and is configured to use this radar apparatus for detection of a detection target.

Radar equipped vehicle of this, since it has such a configuration, as in the conventional radar apparatus equipped vehicle, to control the behavior of the vehicle based on the distance information detected by the radar device, the driver for example the sound that it has detected an obstacle or another vehicle or the like of the road, can be or warning light or vibration, in the radar apparatus equipped vehicle this, which is a detection object road obstacle or another Since the radar device detects the vehicle and the like quickly and reliably, it is possible to perform appropriate control of the vehicle and appropriate warning to the driver without causing the vehicle to make a sudden behavior.

In addition, the radar apparatus mounted on a vehicle of this is, specifically, train, train, of course car for the transport of automobiles and the like passenger and cargo, bicycles, mopeds, amusement park rides, cart of golf course Can also be used.

Moreover, a small ship equipped with a radar apparatus equipped with the radar apparatus of the present invention includes the radar apparatus of the present invention, and uses this radar apparatus for detection of a detection object.

The radar apparatus mounted small boat of this, since it has such a configuration, as in the conventional radar apparatus equipped vehicles, the small boat, and controlling the behavior of a small watercraft based on the distance information detected by the radar device Or the operator is warned by sound, light or vibration that an obstacle such as a reef, another ship or other small ship has been detected. In order to detect obstacles such as reefs, other ships or other small ships, the radar device quickly and surely, it is necessary to detect small ships without causing sudden behavior. Control and appropriate warning to the operator.

Incidentally, the radar apparatus mounted small boat This is specifically a ship can be steered without license or license Small vessels, rowing hand a ship gross tonnage of less than 20 tons, dinghy, jetski , Small bass boats with outboard motors, inflatable boats (rubber boats) with outboard motors, fishing boats, recreational fishing boats, work boats, houseboats, towing boats, sports boats, fishing boats, yachts, open-sea yachts, cruisers or gross tonnage of 20 tons It can be used for the above pleasure boats.

Thus, according to the present invention, it is possible to block a part of the transmission high-frequency signal from leaking to the reception side and outputting an intermediate frequency signal as noise caused by switching of the transmission high-frequency signal to the reception system. A high-frequency transmitter / receiver having a switch, and a high-frequency transmitter / receiver with high reception performance capable of reliably blocking such an intermediate frequency signal as noise even in a transient state of switching a high-frequency signal for transmission, and the same it is possible to provide a high-performance radar equipment that can be quickly reliably detect the detection object using.

  In addition, this invention is not limited to the example of the said embodiment, It does not interfere in various ways within the range which does not deviate from the summary of this invention. For example, in the high-frequency transceiver of the present invention, one input terminal of an operational amplifier (op-amp) that operates at high speed is connected to the output terminal of the IF switch 7, and the other input terminal and output terminal of the operational amplifier are connected to the input terminal. Another IF switch that is the same type as the IF switch and has the same characteristics as possible may be connected to a subsequent circuit of the receiving system. In this case, the operational amplifier operates so as to cancel unnecessary signals such as switching noise generated by the IF switch itself with a similar signal generated by another IF switch. Can be prevented from being input to a circuit subsequent to the receiving system.

It is a block circuit diagram showing typically an example of an embodiment of the 1st high frequency transceiver of a reference example . It is a block circuit diagram showing typically an example of an embodiment of the 2nd high frequency transceiver of a reference example . It is a block circuit diagram showing typically an example of an embodiment of the 3rd high frequency transceiver of the present invention. It is a block circuit diagram showing typically an example of an embodiment of the 4th high frequency transceiver of the present invention. It is a block circuit diagram showing typically other examples of an embodiment of the 3rd high frequency transceiver of the present invention. It is a block circuit diagram showing typically other examples of an embodiment of the 4th high frequency transceiver of the present invention. It is a top view which shows typically the example of the high frequency transmission part of the high frequency transmitter-receiver shown in FIG. It is a block circuit diagram which shows the structure of each part when the conventional high frequency transmitter-receiver is used as a millimeter wave radar. It is a partially broken perspective view which shows the fundamental structure of a nonradiative dielectric track | line. It is a top view of the high frequency transmitter-receiver which has a transmission / reception antenna. It is a top view of the high frequency transmitter-receiver which has a transmitting antenna and a receiving antenna. It is a perspective view which shows the structure of the pulse modulator of a high frequency transmitter / receiver.

Explanation of symbols

1: High frequency oscillator 2: Branch device 3, 3 ', 3 ": RF switch (switch)
4: Hybrid 5: Transmission / reception antenna 6: Mixer 7: IF switch (switch)
8, 8 ': Changeover RF switch (Changeover switch: Single-pole 2-way changeover type)
8 ": 2nd changeover RF switch (2nd changeover switch: single pole 2 direction changeover type)
9: Transmitting antenna
10: Receive antenna
11: Lower flat conductor (upper flat conductor not shown)

Claims (3)

A high-frequency oscillator that generates a high-frequency signal;
A change-over switch for switching whether the high-frequency signal input from the input terminal connected to the high-frequency oscillator is output from one output terminal as a transmission high-frequency signal or from the other output terminal as a local signal; ,
Input coupled to said one output terminal of該切replacement switch, and a second changeover switch with input and output ends to be connected is switched to the output terminal, and the input end or the output end,
A transmission / reception antenna connected to the input / output terminal of the second changeover switch;
Connected between the other output end of the changeover switch and the output end of the second changeover switch, a local signal output to the other output end, and a high-frequency signal received by the transmission / reception antenna A mixer that mixes and outputs an intermediate frequency signal;
A switch connected to the output end of the mixer, shuts off the intermediate frequency signal in the open state, and closes when the high frequency signal for transmission is stable in the non-output state and passes the intermediate frequency signal When,
A filter that is connected to the switch, removes switching noise when the switch is opened and closed, and passes the intermediate frequency signal;
A high-frequency transmitter / receiver having a function of performing a self-diagnosis by inputting a test signal having a frequency lower than a 3 dB cutoff frequency of the filter between an output end of the mixer and the switch. A high-frequency oscillator that generates a high-frequency signal;
A change-over switch for switching whether the high-frequency signal input from the input terminal connected to the high-frequency oscillator is output from one output terminal as a transmission high-frequency signal or from the other output terminal as a local signal; ,
A transmission antenna connected to the one output terminal of the changeover switch;
A receiving antenna connected to the other output end of the changeover switch;
The intermediate switch is connected between the other output terminal of the changeover switch and the receiving antenna, and mixes a local signal output from the other output terminal and a high-frequency signal received by the receiving antenna. A mixer to output,
A switch connected to the output end of the mixer, shuts off the intermediate frequency signal in the open state, and closes when the high frequency signal for transmission is stable in the non-output state and passes the intermediate frequency signal When,
A filter that is connected to the switch, removes switching noise when the switch is opened and closed, and passes the intermediate frequency signal;
A high-frequency transmitter / receiver having a function of performing a self-diagnosis by inputting a test signal having a frequency lower than a 3 dB cutoff frequency of the filter between an output end of the mixer and the switch. The high-frequency transceiver according to claim 1 or 2,
A radar apparatus comprising: a distance information detector that processes the intermediate frequency signal output from the high frequency transmitter / receiver to detect distance information to a detection target.

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