JP2005269592A - Isolator, high-frequency oscillator using the same, high-frequency receiver and radar system, and radar system mounting vehicle and small craft - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a circulator type isolator whose isolation characteristics are improved. <P>SOLUTION: There is provided the isolator, in which a nonreflective terminator 5 is connected to one end of the third dielectric line 3 whose other end is connected to a third connection 4c in the circulator, where first, second and third dielectric lines 1, 2, 3 are radially connected to each other at a marginal portion of a ferrite plate 4. In the isolator, the line length of the third dielectric line 3 is set, in such a way that if a high-frequency signal which has passed through the third dielectric line 3 and has reflected at non-reflecting terminator 5 and then has returned to leak to the first dielectric line 1 is defined as Wa, and a high-frequency signal which has leaked to the first dielectric line 1 through the intermediary of the circulator from the second dielectric line 2 is defined as Wb, and further the phase difference in these central frequencies is defined as δ, δ=(2N+1)×π (where N is an integer) is determined. Since Wa and Wb are combined with their phases just opposite to each other so as to be effectively cancelled, the isolation characteristics thereof become satisfactory. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a high-frequency signal isolator used in a millimeter-wave integrated circuit, a millimeter-wave radar module, or the like. Specifically, a non-reflection terminator is connected to one of input / output transmission lines of a circulator. The present invention relates to an isolator capable of improving isolation characteristics, a high-frequency oscillator and a high-frequency transmitter / receiver using the isolator.

  The present invention also relates to a high-frequency oscillator that generates a millimeter-wave signal using a high-frequency diode and is incorporated in a non-radiative dielectric line-type millimeter-wave integrated circuit, a millimeter-wave radar module, and the like, and a non-radiative dielectric line using the same The present invention relates to a high-frequency transceiver of a type.

  The present invention also relates to a radar apparatus including the above-described high-frequency transmitter / receiver, a radar apparatus-equipped vehicle equipped with the radar apparatus, and a radar apparatus-equipped small ship.

  Conventionally, as a high-frequency signal isolator that is used in a millimeter-wave integrated circuit or millimeter-wave radar module, a circulator type in which a non-reflective termination is connected to one of the input / output transmission lines of the circulator An isolator of this type is known, and a conventional example of such a circulator type isolator is disclosed in Patent Document 1, for example.

  The isolator disclosed in Patent Document 1 is, for example, as shown in a schematic plan view in FIG. 12, in which first, second and third transmission lines 14, 15, 16 for transmitting high-frequency signals are used. Is connected radially to the peripheral edge of the magnetic body 17, and one end is connected to one connection part of a circulator that outputs a high-frequency signal input from one connection part from one of the other adjacent connection parts. In an isolator in which a reflection-free terminator 18 is connected to the other end of the transmission line 16, the line length of the third transmission line 16 is expressed as (2n + 1) / 4 · λg (n is an integer, λg is the first high-frequency signal). 3 in the transmission line 16).

  According to such a conventional isolator, a high-frequency signal input from the first transmission line 14 is output from the second transmission line 15, while one of the high-frequency signals reflected from the output end side of the second transmission line 15 is output. Is input to the third transmission line 16, a part of the high-frequency signal is terminated by the non-reflection terminator 18, and a part of the high-frequency signal reflected from the output end side of the second transmission line 15 is the first. When operating so as not to leak to the input end side of the transmission line 14, a high-frequency signal reflected from the third transmission line 16 and leaking to the first transmission line 14 without being completely terminated by the non-reflection terminator 18. By interfering with a part of the high-frequency signal reflected from the output end side of the second transmission line 15 and leaking from the second transmission line 15 to the first transmission line 14, the second transmission line 15 High-frequency signal reflected on the output end side and leaking to the input end side of the first transmission line 14 is further attenuated So that it is, it is that it is possible to improve the isolation characteristics.

  On the other hand, metal waveguides have been widely used to transmit microwave and millimeter wave high-frequency signals. However, due to recent demands for miniaturization of high-frequency modules, dielectric lines are used as waveguides for high-frequency signals. A high-frequency module used as the above has been developed. In particular, non-radiative dielectric lines (NonRadiative Dielectric Waveguides, hereinafter also referred to as NRD guides) that have low transmission loss of high-frequency signals have attracted attention.

  The basic configuration of this NRD guide is shown in a partially broken perspective view in FIG. As shown in the figure, a rectangular dielectric line 13 having a rectangular cross section or the like is arranged between parallel plate conductors 11 and 12 arranged in parallel with a predetermined interval a. If a ≦ λ / 2 with respect to the wavelength λ of the high-frequency signal, the noise intrusion from the outside to the dielectric line 13 is eliminated and the high-frequency signal is not radiated to the outside. The signal can be propagated efficiently. The wavelength λ of the high frequency signal is a wavelength in the air (free space) at the operating frequency.

  Conventional examples of high-frequency oscillators incorporated in such an NRD guide are shown in perspective views in FIGS. FIG. 13 is a perspective view showing a conventional example of a high frequency oscillator, and FIG. 14 is a perspective view of a wiring board provided with a variable capacitance diode (varactor diode) for the high frequency oscillator. In FIGS. 13 and 14, the parallel plate conductor is not shown. This high-frequency oscillator oscillates a frequency-modulated high-frequency signal by using a combination of a Gunn diode and a varactor diode. A high-frequency transceiver or millimeter-wave radar module using such a high-frequency oscillator is used. Has been developed. FIG. 15 is a plan view showing an example of a millimeter wave radar module configured by incorporating a conventional high frequency oscillator as the millimeter wave signal oscillating unit 102.

  The high frequency oscillator shown in FIG. 13 includes a voltage controlled oscillator V and a circulator E. First, the voltage controlled oscillator V, which is a component of the high-frequency oscillator shown in FIG. 13 and 14, 82 is a metal member such as a substantially rectangular parallelepiped metal block for mounting (mounting) the Gunn diode 83, 83 is a Gunn diode which is a kind of high-frequency diode that oscillates millimeter waves, and 84 is a metal. A wiring board provided with a choke-type bias supply line 84a that is installed on one side of the member 82 and functions as a low-pass filter that supplies a bias voltage to the Gunn diode 83 and prevents leakage of high-frequency signals; 85 is a choke-type bias supply line 84a And a strip conductor such as a metal foil ribbon connecting the upper conductor of the Gunn diode 83, 86 is a metal strip resonator in which a resonant metal strip line 86a is provided on a dielectric substrate, and 87 is resonated by the metal strip resonator 86. This is a dielectric line that guides a high-frequency signal to the outside of the millimeter-wave signal oscillator.

Further, in the middle of the dielectric line 87, a wiring board 88 on which a varactor diode 80, which is a frequency modulation diode and is a kind of variable capacitance diode, is mounted. The bias voltage application direction of the varactor diode 80 is set to a direction (electric field direction) perpendicular to the propagation direction of the high-frequency signal in the dielectric line 87 and parallel to the main surface of the parallel plate conductor. Further, the bias voltage application direction of the varactor diode 80 coincides with the electric field direction of the high-frequency signal of the LSM ₀₁ mode propagating through the dielectric line 87, whereby the high-frequency signal and the varactor diode 80 are electromagnetically coupled to each other. The frequency of the high-frequency signal can be controlled by changing the capacitance of the varactor diode 80 by controlling the voltage. Reference numeral 89 denotes a high dielectric constant dielectric plate for impedance matching between the varactor diode 80 and the dielectric line 87.

  Further, as shown in FIG. 14, a second choke-type bias supply line 90 is formed on one main surface of the wiring board 88, and a varactor diode 80 is disposed in the middle of the second choke-type bias supply line 90. . A connection electrode 81 is formed at a connection portion between the second choke-type bias supply line 90 and the varactor diode 80.

  The high frequency signal oscillated from the Gunn diode 83 is led to the dielectric line 87 through the metal strip resonator 86. Next, a part of the high frequency signal is reflected by the varactor diode 80 and returns to the Gunn diode 83 side. This reflected signal changes as the capacitance of the varactor diode 80 changes, and the oscillation frequency changes.

  Next, the circulator E, which is a component of the high-frequency modulator shown in FIG. 13, is arranged at a predetermined interval on the peripheral portions of the two ferrite plates 91a and 91b arranged in parallel to the parallel plate conductors, and each is in millimeters. The first connection portion 92a, the second connection portion 92b, and the third connection portion 92c, which are input / output ends of the wave signal, have one end of the dielectric line 87 at the first connection portion 92a. One end of the dielectric line 93 is connected to the second connection part 92b, one end of the dielectric line 94 is connected to the third connection part 92c, and the millimeter wave signal input from the other end of the dielectric line 87 is converted to the ferrite plate 91a. , 91b is output from the output end 93a, which is the other end of the dielectric line 93 adjacent in the counterclockwise direction, and a part of this output is reflected and returned to be input from the output end 93a. Input to one end of dielectric line 94 adjacent counterclockwise in the plane of 91b and output from the other end It is configured to be.

  The high frequency modulator shown in FIG. 13 is configured by connecting a voltage controlled oscillator V and a circulator E by a dielectric line 87 and connecting a non-reflection terminator 95 to the other end of the dielectric line 94. The millimeter wave signal generated by the voltage controlled oscillator V is transmitted from the first connection portion 92a of the circulator E to the second connection portion 92b, and is extracted from the output end 93a as a millimeter wave oscillation output. In this configuration, the voltage controlled oscillator V and the output end 93a are isolated so that the circulator E and the non-reflecting terminator 95 operate as isolators so that the millimeter wave oscillation output of the voltage controlled oscillator V does not return to the voltage controlled oscillator V. The voltage controlled oscillator V operates so as to oscillate stably. Technologies relating to such a high-frequency oscillator are disclosed in, for example, Patent Documents 2 to 5.

  Further, the millimeter wave radar module shown in FIG. 15 is of the FMCW (Frequency Modulation Continuous Waves) system, and its operation principle is as follows. An input signal whose voltage amplitude changes in a triangular wave, sine wave, etc. is input to the modulation signal input terminal of the millimeter wave signal oscillation unit 102 composed of a high frequency oscillator as shown in FIG. 13, and the output signal is frequency modulated. Then, the output frequency shift of the millimeter wave signal oscillating unit 102 is shifted so as to become a triangular wave, a sine wave, or the like. When an output signal (transmission wave) is radiated from the transmission / reception antenna 106, if there is a target in front of the transmission / reception antenna 106, a reflected wave (reception wave) is reflected from the target with a time difference corresponding to the round-trip propagation speed of the radio wave. Will come back. At this time, an intermediate frequency signal corresponding to the frequency difference between the transmission wave and the reception wave is output to the intermediate frequency output terminal on the output side of the mixer 110.

By analyzing the frequency components such as the output frequency of the output of the intermediate frequency output terminal, F _if = 4R · fm · Δf / c (F _if : IF (Intermediate Frequency) output frequency, R: distance , Fm: modulation frequency, Δf: frequency shift width, c: speed of light)), the distance to the target can be obtained.

  Technologies relating to millimeter wave radar modules using such a high-frequency oscillator are disclosed in, for example, Patent Documents 6 to 8.

An example of a conventional radar device and a vehicle equipped with the radar device is disclosed in Patent Document 9, for example.
Japanese Unexamined Patent Publication No. 7-235808 JP-A-6-188633 JP-A-6-177650 JP-A-6-177649 JP-A-6-97735 JP-A-6-174824 Japanese Patent Laid-Open No. 10-22864 Japanese Patent Laid-Open No. 10-224257 JP 2003-35768 A

  However, in the conventional isolator disclosed in Patent Document 1, when a high-frequency signal is reflected mainly by the non-reflective terminator 18, in practice, the phase advance of the high-frequency signal changes. If the line length of the third transmission line 16 is set as described above so that the isolation characteristic is good under the assumption that there is no significant phase change, the above-mentioned 2 leaking into the first transmission line 14 Since two high-frequency signals are shifted from the opposite phase and combined, the high-frequency signal that is reflected on the output end side of the second transmission line 15 and leaks to the input end side of the first transmission line 14 is sufficiently obtained. There was a problem that it could not be attenuated.

  The present invention has been devised in order to solve the above-described problems in the prior art that are desired to be improved. The object of the present invention is to provide a reflection-free terminator on one of the transmission lines for input / output of the circulator. An object of the present invention is to provide an isolator having improved isolation characteristics in a connected circulator type isolator.

  In addition, the conventional high-frequency oscillator as shown in FIG. 13 has a narrow frequency bandwidth where high isolation can be obtained, as shown in the graph of the isolation characteristics of one stage of the circulator as a component of the high-frequency modulator in FIG. In order to stably oscillate the high-frequency oscillator in a region where the isolation can be larger than a predetermined value such as 30 dB or more, the frequency band to oscillate is limited (for example, less than 1 GHz in the example of FIG. 7). was there.

  In addition, when a conventional high-frequency oscillator is incorporated in a millimeter-wave radar module or the like, the millimeter-wave radar module is mounted in an engine room or the like of an automobile where the temperature changes drastically. Since it depends on the temperature, there is a problem that the radar detection performance may be deteriorated by the high-frequency oscillator outputting a millimeter wave at a frequency at which the circulator cannot be isolated due to the environmental temperature.

  In a conventional millimeter-wave radar module, when it is desired to further modulate the millimeter-wave oscillation output and perform millimeter-wave transmission / reception with low noise, the conventional high-frequency oscillator uses a pulse-shaped millimeter wave from the pulse modulator. When the signal returns to the high-frequency oscillator, a stronger oscillation instability factor is added to the voltage-controlled oscillator, which causes a problem that the circulator is insufficiently isolated.

  Further, with respect to these problems, there can be considered a solution means for constructing a similar high-frequency oscillator using a two-stage circulator as proposed by the present applicant in Japanese Patent Laid-Open No. 2003-218609. However, there has been a demand for further improvement in that it is desired to further increase the frequency bandwidth in which isolation of a predetermined value or more is ensured.

  The present invention has been completed in view of the above circumstances, and an object of the present invention is to widen a frequency bandwidth in which isolation of a predetermined value or more is ensured and to widen a stable oscillation frequency bandwidth. Another object of the present invention is to provide a high-frequency oscillator that can be operated stably even if the frequency characteristics of the high-frequency oscillator are affected by the operating environment temperature, and a high-frequency transceiver using the same.

  Another object of the present invention is to provide a radar apparatus equipped with such a high-performance high-frequency transmitter / receiver, a radar apparatus-equipped vehicle equipped with the radar apparatus, and a radar apparatus-equipped small ship.

  In the first isolator of the present invention, the first, second, and third transmission lines for transmitting a high-frequency signal are connected to the peripheral portion of the magnetic material radially at the first, second, and third connecting portions, respectively. To the circulator that outputs the high-frequency signal input from one of the connection portions from one of the other adjacent connection portions, to the other end of the third transmission line having one end connected to the third connection portion In an isolator to which a non-reflection terminator is connected, the line length of the third transmission line is reflected by the non-reflection terminator through the third transmission line and returned to the first transmission line. The leaked part of the high-frequency signal is referred to as Wa, the other part of the high-frequency signal leaked from the second transmission line via the circulator to the first transmission line is referred to as Wb, and the center of these Wa and Wb The phase difference in frequency When a, δ = (2N + 1) · π (although, N represents an integer.) Is characterized in that set to be.

  In the second isolator of the present invention, the first, second, and third transmission lines for transmitting a high-frequency signal are connected to the peripheral portion of the magnetic material radially at the first, second, and third connection portions, respectively. The first and second circulators that output the high-frequency signal input from one of the connection sections from one of the other adjacent connection sections, and the second transmission line of the first circulator is the second circulator. A non-reflective terminator at the other end of the third transmission line that is connected to serve as the first transmission line of the circulator and has one end connected to the third connection part. Is connected to the first transmission line of the first circulator from the first transmission line to the second transmission line and from the second transmission line to the first transmission line. The frequency dependence of the isolation characteristic from the high-frequency signal transmitted to the transmission line, the high-frequency signal transmitted from the first transmission line of the second circulator to the second transmission line, and the second transmission line The frequency dependence of the isolation characteristic from the high-frequency signal transmitted from the first to the first transmission line is different.

  In the second isolator of the present invention, the first and second circulators each have a length of the third transmission line passing through the third transmission line and the reflection-free termination. A part of the high-frequency signal that has been reflected by the device and leaked to the first transmission line is defined as Wa, and the other part that has leaked from the second transmission line to the first transmission line via the circulator Is set such that δ = (2N + 1) · π (where N is an integer), where Wb is a high-frequency signal and δ is a phase difference at the center frequency between Wa and Wb. It is a feature.

  A first high-frequency oscillator according to the present invention includes two ferrite plates arranged between parallel plate conductors arranged at intervals of half or less of the wavelength of a high-frequency signal so as to face each other on the inner surface of the parallel plate conductor. An input dielectric line for inputting a high frequency signal, a termination dielectric line provided with a non-reflective termination at the tip, and the input dielectric, which are arranged substantially radially with respect to the two ferrite plates. First and second circulators each having an output dielectric line for outputting a high-frequency signal input to the body line are connected to each other, and the first and second circulators are connected to the first circulator. The output dielectric line of the circulator is connected by serving also as the input dielectric line of the second circulator, and the input guide of the first circulator is connected. A voltage-controlled oscillator is connected to an input end of the body line to which the high-frequency signal is input, and the high-frequency signal and the output transmitted from the input dielectric line to the output dielectric line of the first circulator The frequency dependence of the isolation characteristic from the high frequency signal transmitted from the dielectric line for input to the input dielectric line, and the transmission from the input dielectric line of the second circulator to the output dielectric line The frequency dependency of the isolation characteristic between the high frequency signal and the high frequency signal transmitted from the output dielectric line to the input dielectric line is different.

  In the first high-frequency oscillator of the present invention, in the above configuration, the frequency dependence varies at least one of an interval and a dimension of the two ferrite plates of the first circulator and the second circulator. It is characterized by being adjusted by this.

  A second high-frequency oscillator according to the present invention comprises any one of the first and second isolators according to the present invention and a voltage-controlled oscillator connected to an input terminal of the isolator for generating a high-frequency signal. It is a feature.

The first high-frequency transceiver of the present invention is:
Between parallel plate conductors arranged at intervals of 1/2 or less of the wavelength of the millimeter wave signal,
A millimeter wave signal oscillating unit attached to the first dielectric line and outputting a millimeter wave signal output from the high frequency oscillator to the first dielectric line;
A pulse modulator interposed in the middle of the first dielectric line to pulse the millimeter wave signal and output it from the first dielectric line as a millimeter wave signal for transmission;
Proximity is arranged so that one end side is electromagnetically coupled to the first dielectric line, or one end is joined to the first dielectric line, and a part of the millimeter wave signal for transmission is propagated to the mixer side A second dielectric line,
A first connecting portion, a second connecting portion, and a third connecting portion arranged at predetermined intervals on a peripheral portion of a ferrite plate arranged in parallel to the parallel plate conductor and serving as input / output ends of the millimeter wave signal, respectively. A circulator for outputting the millimeter wave signal input from one of the connection portions from the other connection portion adjacent in the clockwise or counterclockwise direction in the plane of the ferrite plate, A circulator to which the first connection portion is connected to an output end of the millimeter wave signal of the first dielectric line;
A third dielectric line connected to the second connection part of the circulator, for propagating the transmitting millimeter-wave signal and having a transmission / reception antenna at a tip part;
A fourth wave connected to the third connection part of the circulator, received by the transmission / reception antenna, propagates through the third dielectric line, and propagates the received wave output from the third connection part to the mixer. A dielectric line;
The middle part of the second dielectric line and the middle part of the fourth dielectric line are close to each other or joined so as to be electromagnetically coupled, and a part of the millimeter wave signal for transmission and the received wave A mixer that generates an intermediate frequency signal by mixing
A non-reflective terminator connected to the end of the second dielectric line opposite to the mixer;
The high-frequency oscillator of the millimeter-wave signal oscillating unit is the first high-frequency oscillator according to the present invention having any one of the above-described configurations.

Moreover, the second high-frequency transceiver of the present invention is
Between parallel plate conductors arranged at intervals of 1/2 or less of the wavelength of the millimeter wave signal,
A millimeter wave signal oscillating unit attached to the first dielectric line and outputting a millimeter wave signal output from the high frequency oscillator to the first dielectric line;
A pulse modulator interposed in the middle of the first dielectric line to pulse the millimeter wave signal and output it from the first dielectric line as a millimeter wave signal for transmission;
Proximity is arranged so that one end side is electromagnetically coupled to the first dielectric line, or one end is joined to the first dielectric line, and a part of the millimeter wave signal for transmission is propagated to the mixer side A second dielectric line,
A first connecting portion, a second connecting portion, and a third connecting portion arranged at predetermined intervals on a peripheral portion of a ferrite plate arranged in parallel to the parallel plate conductor and serving as input / output ends of the millimeter wave signal, respectively. A circulator for outputting the millimeter wave signal input from one of the connection portions from the other connection portion adjacent in the clockwise or counterclockwise direction in the plane of the ferrite plate, A circulator to which the first connection portion is connected to an output end of the millimeter wave signal of the first dielectric line;
A third dielectric line connected to the second connection portion of the circulator, for propagating the millimeter wave signal for transmission, and having a transmission antenna at a tip portion;
A fourth dielectric line provided with a receiving antenna at the front end and a mixer at the other end;
A fifth dielectric that is connected to the third connection portion of the circulator, propagates a millimeter-wave signal received and mixed by the transmitting antenna, and attenuates the millimeter-wave signal by a non-reflective terminator provided at a tip portion. Tracks,
The middle part of the second dielectric line and the middle part of the fourth dielectric line are close to each other or joined so as to be electromagnetically coupled, and a part of the millimeter wave signal for transmission and the received wave A mixer that generates an intermediate frequency signal by mixing
A non-reflective termination connected to the opposite end of the mixer of the second dielectric line;
The high-frequency oscillator of the millimeter-wave signal oscillating unit is the first high-frequency oscillator according to the present invention having any one of the above-described configurations.

  A third high-frequency transmitter / receiver according to the present invention includes the second high-frequency oscillator according to the present invention and the high-frequency signal connected to the output end of the high-frequency oscillator so as to branch one output end and the other output end. A modulator connected to the one output terminal, a modulator for modulating the high-frequency signal branched to the one output terminal and outputting a high-frequency signal for transmission, and a magnetic material around the magnetic body. A first terminal, a second terminal, and a third terminal, and in this order, a high-frequency signal input from one of the terminals is output from the next adjacent terminal, and the output of the modulator is the first terminal A circulator input to a terminal, a transmission / reception antenna connected to the second terminal of the circulator, and the other output terminal of the branching unit and the third terminal of the circulator, Branch to the other output It is characterized in that it comprises a mixer for outputting the intermediate frequency signal by mixing the radio frequency signal received by the high-frequency signal and the reception antenna.

  A fourth high-frequency transmitter / receiver according to the present invention includes the above-described second high-frequency oscillator according to the present invention and the high-frequency signal connected to the output end of the high-frequency oscillator to branch one output end and the other output end. And a modulator connected to the one output terminal for modulating a high-frequency signal branched to the one output terminal and outputting a high-frequency signal for transmission, and an output terminal of the modulator One end connected to the isolator that transmits the high-frequency signal for transmission from the one end side to the other end side, a transmission antenna connected to the isolator, and the other output end side of the branching device A high-frequency signal that is connected between the receiving antenna and the other output end of the branching device and the receiving antenna and that is branched to the other output end and a high-frequency signal received by the transmitting / receiving antenna are mixed. Intermediate frequency It is characterized in that it comprises a mixer for outputting the issue.

  The radar apparatus according to the present invention is a distance from a first to fourth high-frequency transmitter / receiver according to the present invention having the above-described configuration and a detection target by processing the intermediate frequency signal output from the high-frequency transmitter / receiver. And a distance information detector for detecting information.

  The radar device-equipped vehicle of the present invention includes the radar device of the present invention having the above-described configuration, and is characterized in that this radar device is used for detection of an object to be detected.

  A small ship equipped with a radar apparatus according to the present invention includes the radar apparatus according to the present invention having the above-described configuration, and is characterized in that this radar apparatus is used for detection of a detection target.

  According to the first isolator of the present invention, the first, second, and third transmission lines for transmitting a high-frequency signal are connected to the peripheral portion of the magnetic material at the first, second, and third connection portions, respectively, radially. Other than the third transmission line, one end of which is connected to the circulator for outputting the high-frequency signal input from one of the connection portions from one of the other connection portions adjacent to the circulator. In the isolator having a reflection-free terminator connected to the end, the length of the third transmission line is reflected by the reflection-free terminator through the third transmission line and returned to the first transmission line. Wa is a part of the high-frequency signal leaked to the line and Wb is a part of the other high-frequency signal leaked from the second transmission line to the first transmission line via the circulator. At the center frequency of Since the difference is set to δ, δ = (2N + 1) · π (where N is an integer), the phase difference δ between Wa and Wb is δ = (2N + 1) · π Therefore, when the high-frequency signal is reflected by the non-reflecting terminator, the phase advance of the high-frequency signal changes, but the two partial high-frequency signals leaking to the first transmission line can be reliably detected. Since the phases can be exactly opposite to each other and effectively cancel each other, the isolation characteristics can be improved.

  According to the second isolator of the present invention, the first, second, and third transmission lines that transmit the high-frequency signal are connected to the peripheral portion of the magnetic material at the first, second, and third connection portions, respectively, radially. The first and second circulators that output the high-frequency signal input from one of the connection portions from one of the other adjacent connection portions, and the second transmission line of the first circulator is the second transmission line The second circulator is connected to serve as the first transmission line, and is connected to the other end of the third transmission line with one end connected to the third connection part. In an isolator to which a terminator is connected, the high-frequency signal transmitted from the first transmission line of the first circulator to the second transmission line and the second transmission line from the second transmission line. The frequency dependence of the isolation characteristic from the high-frequency signal transmitted to one transmission line, the high-frequency signal transmitted from the first transmission line to the second transmission line of the second circulator, and the second Since the frequency dependence of the isolation characteristic of the high-frequency signal transmitted from the transmission line to the first transmission line is different, the isolation can be achieved without biasing only to a specific frequency. The frequency at which the two circulators obtain the maximum isolation are set to different values, the frequency bandwidth that ensures the isolation greater than the predetermined value is set, and the frequency at which the first and second circulators obtain the maximum isolation are the same. Compared with the case of setting to, it can be widened.

  According to the second isolator of the present invention, in the above configuration, each of the first and second circulators sets the line length of the third transmission line through the third transmission line. A part of the high-frequency signal reflected by the reflection terminator and leaked to the first transmission line is defined as Wa, and the other high-frequency signal leaked from the second transmission line to the first transmission line via the circulator. When some high-frequency signals are Wb and the phase difference at the center frequency between these Wa and Wb is δ, δ = (2N + 1) · π (where N is an integer) is set. Sometimes, since the phase difference δ between Wa and Wb is δ = (2N + 1) · π, when the high-frequency signal is reflected by the non-reflection terminator, the phase advance of the high-frequency signal changes. 2 above leaking into the first transmission line Some of the high-frequency signal in the surely just opposite phases of, since it is possible to effectively so each other are canceled, and that it is possible to improve the isolation characteristics.

  According to the first high frequency oscillator of the present invention, with the above configuration, the high frequency signal transmitted from the input dielectric line of the first circulator to the output dielectric line and the output dielectric line to the input dielectric line are provided. The frequency dependence of the isolation characteristics from the transmitted high-frequency signal and the high-frequency signal transmitted from the input dielectric line of the second circulator to the output dielectric line and transmitted from the output dielectric line to the input dielectric line Since the frequency dependence of the isolation characteristic with respect to the high frequency signal is different, it is possible to achieve isolation without biasing only to a specific frequency, so that the first and second circulators can achieve maximum isolation. The frequency band at which the isolation frequency is set to a different value and the isolation of a predetermined value or more is ensured. And the second circulator can be made wider than the case where the frequency at which the maximum circulator takes the maximum isolation is set to be the same, so that the millimeter wave signal returning to the high frequency oscillator in a wide frequency range can be sufficiently suppressed, It is possible to oscillate stably. Further, when the operating frequency range is limited, compared to the case where the frequency at which the first and second circulators obtain the maximum isolation are set to be the same, the operating frequency range is not biased toward a specific frequency. Since isolation can be obtained, the predetermined value of isolation to be secured can be set high, and even when oscillation instability factors such as the pulse of the millimeter wave signal returning to the high frequency oscillator are added It is possible to oscillate stably.

  Further, according to the first high-frequency oscillator of the present invention, the frequency dependency is adjusted by making at least one of the interval and the dimension of the two ferrite plates of the first circulator and the second circulator different. The transmission characteristics from the input dielectric line to the output dielectric line of each circulator may be deteriorated, for example, when adjusting the dimensions and transmission characteristics of the input dielectric line or the output dielectric line. Therefore, it is possible to adjust the isolation while maintaining good transmission characteristics. Therefore, the frequency at which the first and second circulators obtain the maximum isolation can be easily and surely set to different values, so that the isolation of a predetermined value or more can be set. The frequency bandwidth at which the first and second circulators provide maximum isolation. Therefore, the millimeter-wave signal returning to the high-frequency oscillator is sufficiently suppressed in a wide frequency range, and further from the input dielectric line to the output dielectric line. Oscillation can be more stably owing to good transmission characteristics. Also, when limiting the operating frequency range, it is necessary to ensure that the isolation can be fine-tuned in the operating frequency range without biasing only to a specific frequency while eliminating the characteristic variation factor due to misalignment during assembly. The predetermined value of isolation can be set high, and even when an unstable oscillation factor such as a pulse of the millimeter wave signal returning to the high-frequency oscillator is applied, it is possible to oscillate more stably. .

  In addition, after assembly, it is possible to easily replace the ferrite plate with another one while eliminating the characteristic variation factor during assembly in the same way. It is possible to easily change and adjust the adjustment characteristics.

  According to the second high-frequency oscillator of the present invention, it comprises any one of the first and second isolators and a voltage-controlled oscillator that is connected to the input end of the isolator and generates a high-frequency signal. Since the isolator has good isolation characteristics, the isolator sufficiently attenuates the unstable high-frequency signal that returns to the voltage-controlled oscillator, so that it can stably generate a high-frequency signal with a good oscillation output. It will be possible.

  According to the first and second high-frequency transceivers of the present invention, the high-frequency oscillator of the millimeter wave signal oscillating unit is the first high-frequency oscillator of the present invention as described above. Even when the oscillation frequency changes, the millimeter-wave signal returning to the high-frequency oscillator is sufficiently suppressed to maintain a good oscillation state, so that it can be operated stably even if the operating environment temperature changes. High performance. Further, even when the millimeter wave oscillation output is further subjected to pulse modulation or the like, it can be stably operated, and the radar detection accuracy and the identification accuracy when applied to a millimeter wave radar or the like can be improved.

  According to the third high-frequency transmitter / receiver of the present invention, the second high-frequency oscillator of the present invention and the high-frequency signal connected to the output end of the high-frequency oscillator are branched to output one end and the other end. A branching device that outputs to the output end, a modulator that is connected to the one output end, modulates the high-frequency signal branched to the one output end and outputs a high-frequency signal for transmission, and the surroundings of the magnetic body The first terminal, the second terminal, and the third terminal, and in this order, the high-frequency signal input from one of the terminals is output from the next adjacent terminal, and the output of the modulator is the first terminal. A circulator input to one terminal, a transmission / reception antenna connected to the second terminal of the circulator, and the other output terminal of the branching unit and the third terminal of the circulator. The other output end Since it has a mixer that mixes the branched high-frequency signal and the high-frequency signal received by the transmitting / receiving antenna and outputs an intermediate frequency signal, the high-frequency oscillator is reflected by each component and returns to the high-frequency oscillator Even if there are high-frequency signals with various phases and intensities due to different transmission distances, high-frequency signals are output stably with good oscillation output, so that high-frequency signals that can be easily identified on the receiving side can be transmitted. It will be of performance.

  According to the fourth high-frequency transmitter / receiver of the present invention, the second high-frequency oscillator of the present invention and the high-frequency signal connected to the output end of the high-frequency oscillator are branched to one output end and the other end. A branching device that outputs to the output end, a modulator that is connected to the one output end, modulates the high-frequency signal branched to the one output end, and outputs a high-frequency signal for transmission; and One end connected to the output end, an isolator that transmits the high frequency signal for transmission from the one end side to the other end side, a transmission antenna connected to the isolator, and a connection to the other output end side of the branching device A reception antenna, a high-frequency signal that is connected between the other output end of the branching device and the reception antenna, and that is branched to the other output end and a high-frequency signal received by the transmission / reception antenna Inside Because it has a mixer that outputs a frequency signal, even in a high-frequency transmitter / receiver having a separate antenna, the high-frequency oscillator is reflected by each component and returned to the high-frequency oscillator because the transmission distance is different. Even if there are high-frequency signals having various phases and intensities, a high-frequency signal is stably output with a good oscillation output, so that a high-frequency signal that can be easily identified on the receiving side can be transmitted.

  According to the radar apparatus of the present invention, any one of the first to fourth high-frequency transmitters / receivers of the present invention having the above-described configuration and the intermediate frequency signal output from the high-frequency transmitter / receiver are processed to the detection target. Because it has a distance information detector that detects the distance information, the high-frequency transmitter / receiver has high performance and is stable. The radar apparatus can reliably detect the detection object.

  According to the vehicle equipped with the radar apparatus of the present invention, since the radar apparatus of the present invention having the above-described configuration is provided and this radar apparatus is used for detection of the detection target object, the other radar vehicle is a detection target object quickly and reliably. Radar device that can detect a vehicle and an obstacle, for example, without causing the vehicle to take a sudden action to avoid them, for example, to perform appropriate control of the vehicle and appropriate warning to the driver It becomes an on-board vehicle.

  According to the small ship equipped with the radar apparatus of the present invention, the radar apparatus of the present invention having the above-described configuration is provided, and this radar apparatus is used for detection of the detection object. Because small boat obstacles can be detected, for example, appropriate control of small boats and appropriate warnings to pilots can be made without causing the small boats to take a sudden action to avoid them. A small ship equipped with a radar device.

  First, the first isolator of the present invention will be described in detail below with reference to the drawings.

  FIG. 1 is a schematic plan view showing an example of an embodiment of a first isolator of the present invention. FIG. 11 is a schematic partially broken perspective view showing a basic configuration of a non-radiative dielectric line. FIG. 2 is a diagram showing the dependence of the isolation characteristics on the phase difference δ in the example of the isolator shown in FIG. In FIG. 1, reference numerals 1, 2 and 3 denote dielectric lines as transmission lines, which are first, second and third dielectric lines, respectively. Further, 4 is a ferrite plate as a magnetic material, 5 is a non-reflective terminator, and 4a, 4b and 4c are first, second and third connecting portions, respectively. Wa and Wb are respectively a high frequency signal leaking from the second dielectric line 2 to the first dielectric line 1 and a high frequency signal leaking from the third dielectric line 3 to the first dielectric line 1. Show. In FIG. 11, 11 and 12 are parallel plate conductors, and 13 is a dielectric line.

  The isolator of the example shown in FIG. 1 includes a first dielectric line 1, a second dielectric line 2, and a third dielectric line 3 that transmit a high-frequency signal. In the circulator that is connected by the connection portion 4a, the second connection portion 4b, and the third connection portion 4c, and outputs a high-frequency signal input from one connection portion from one of the other connection portions adjacent to the third circulator. In an isolator in which the non-reflection terminator 5 is connected to the other end of the third dielectric line 3 having one end connected to the connection portion 4c, the line length of the third dielectric line 3 is transmitted as a high frequency to be transmitted. Of the signal, the signal passes through the third dielectric line 3 and is reflected by the non-reflecting terminator 5 and returned from the third connection portion 4c through the circulator (ferrite plate 4) to the first connection portion 4a. Part of the high frequency leaked into the dielectric line 1 The other one leaked from the first connection part 4a to the first dielectric line 1 from the second transmission line 2 through the circulator (ferrite plate 4) from the second transmission line 2 The high-frequency signal of the part is Wb, and the phase difference at the center frequency between Wa and Wb is δ, and δ = (2N + 1) · π (where N is an integer). It is.

  Specifically, in this configuration, the first dielectric line 1, the second dielectric line 2, and the third dielectric line 3 are dielectric lines that are components of the non-radiative dielectric line shown in FIG. The first, second, and third dielectric lines 1, 2, and 3 function as first, second, and third transmission lines using nonradiative dielectric lines, respectively. It is.

  As shown in a partially broken perspective view in FIG. 11, the basic configuration of this non-radiative dielectric line is a dielectric having a rectangular cross section between parallel plate conductors 11 and 12 arranged in parallel with a predetermined interval a. The body line 13 is arranged such that the interval a is a ≦ λ / 2 with respect to the wavelength λ of the high-frequency signal. As a result, the intrusion of noise from the outside to the dielectric line 13 can be eliminated, and the emission of the high frequency signal to the outside can be eliminated, and the high frequency signal can be propagated through the dielectric line 13 with almost no loss. The wavelength λ is the wavelength of the high frequency signal in the air (free space) at the operating frequency.

  The example of the first isolator of the present invention shown in a plan view in FIG. 1 shows an example in which nonradiative dielectric lines are used as the first, second, and third transmission lines, and the wavelength of the high-frequency signal is shown. Between the parallel plate conductors (not shown in FIG. 1) having a distance of 1/2 or less of the first, second and third dielectric lines 1, 2, 3 and the ferrite plate 4 and the non-reflective The terminator 5 is sandwiched.

  In the first isolator of the present invention, as the first, second and third transmission lines, in addition to such a dielectric line, a strip line, a microstrip line, a coplanar line, a grounded coplanar line, A slot line, a waveguide, a dielectric waveguide, or the like may be used.

  In the example of the first isolator of the present invention shown in FIG. 1, the high frequency signal input to the first dielectric line 1 is input from the first connection portion 4a and adjacent to the second connection as in the conventional isolator. While being output from the unit 4 b and output from the second dielectric line 2, a part of the high-frequency signal reflected on the output end side of the second dielectric line 2 returns to the second dielectric line 2. Non-reflective terminator that is input from the second connection portion 4 b, output from the adjacent third connection portion 4 c, input to the third dielectric line 3, and connected to the other end of the third dielectric line 3 By terminating at 5, the second dielectric line 2 operates so as not to leak a high frequency signal from the first dielectric line 1. However, the setting of the line length of the third dielectric line 3 to which the non-reflective terminator 5 is connected is different from the conventional one. In the first isolator of the present invention, the line of the third dielectric line 3 is Since the length is set to be δ = (2N + 1) · π as described above, the high-frequency signal leaking from the second dielectric line 2 to the first dielectric line 1 and the third dielectric Even when the high-frequency signal leaking from the body line 3 to the first dielectric line 1 is reflected by the non-reflection terminator 5, the phase advance of the high-frequency signal changes reliably. Since the phase can be exactly reversed and they can be effectively interfered with each other so as to cancel each other, the isolation characteristics can be improved.

  FIG. 2 is a diagram showing the dependence of this isolation characteristic on the phase difference δ. The horizontal axis and the vertical axis are the phase difference (unit: radians) and isolation (no unit), respectively. The curve shows the dependence of the isolation characteristics due to the phase difference δ. Here, the isolation is an amount representing the intensity of the high frequency signal returned from the output end side to the input end side with respect to the intensity (unit: watt (W)) of the input high frequency signal as a ratio. The smaller the isolation, the better the isolation characteristics.

  The isolation characteristic of the example of the first isolator of the present invention shown in FIG. 1 shows that the isolation changes according to A · cos δ (A is a proportional coefficient and is a real number), as shown in the diagram of FIG. Then, it leaks from the second dielectric line 2 to the third dielectric line 3 through the second connection part 4 b, the ferrite plate 4 and the third connection part 4 c, and passes through the third dielectric line 3. The high-frequency signal Wa reflected by the non-reflection terminator 5 and leaked to the first dielectric line 1 through the third connection portion 4c, the ferrite plate 4 and the first connection portion 4a, and the second The first dielectric is reflected from the output end side, which is the other end side of the dielectric line 2, and passes through the second connection line 4 b, the ferrite plate 4, and the first connection part 4 a from the second dielectric line 2. The phase difference δ at the center frequency from the high-frequency signal Wb leaked to the line 1 is ± π, ± 3π ···, (2N + 1) · π (although, N represents an integer.) When an isolation is smallest characteristic.

  Here, the phase change when the high frequency signal leaks from the second connection portion 4b to the first connection portion 4a and the high frequency signal leaks from the third connection portion 4c to the first connection portion 4a. If the phase change is the same and the phase of the high frequency signal does not change when the high frequency signal is reflected by the non-reflecting terminator 5, then the second dielectric line 2 to the third dielectric line 3, a high frequency signal that leaks to the first dielectric line 1 through the third dielectric line 3, is reflected by the non-reflecting terminator 5, and leaks back to the first dielectric line 1. The phase difference from the high-frequency signal leaking to the dielectric line 1 is equal to the phase change of the high-frequency signal while reciprocating the third dielectric line 3, and at this time, the line length of the third dielectric line 3 is , (2n + 1) / 4 · λg (n is an integer, λg is a high-frequency signal in the third dielectric line 3) The second dielectric line 2 through the third dielectric line 3 to the first dielectric line 1 and the second connection from the second dielectric line 2 to the second connection. The phase difference from the high-frequency signal leaking to the first dielectric line 1 through the portion 4b, the ferrite plate 4 and the first connection portion 4a can be exactly reversed.

  However, in practice, in most cases, when the high frequency signal is reflected by the non-reflecting terminator 5, the phase of the high frequency signal changes. The reason for this is that the non-reflecting terminator 5 is usually deviated from ideal characteristics, and the phase of the high-frequency signal is advanced or delayed when the high-frequency signal is reflected by the reactance component of the reflection coefficient. It is.

  Actually, the phase when the high frequency signal leaks from the second dielectric line 2 to the first dielectric line 1 through the second connection part 4b, the ferrite plate 4 and the first connection part 4a. And a change in phase when a high-frequency signal leaks from the third dielectric line 3 to the first dielectric line 1 through the third connection portion 4c, the ferrite plate 4, and the first connection portion 4a. Can be different. The reason for this is that the change in phase is, for example, each of the first dielectric line 1, the second dielectric line 2, and the third dielectric line 3 arranged radially around the ferrite plate 4. This is because the angle formed may vary depending on the displacement of the arrangement.

  Therefore, in practice, the length L corresponding to the phase difference of the high-frequency signal generated by factors other than the line length of the third dielectric line 3 in the two different paths as described above is set to be equal to that of the third dielectric line 3. If the line length is corrected, the second dielectric line 2, which is the two different paths, leaks to the third dielectric line 3, passes through the third dielectric line 3, and is reflected by the non-reflection terminator 5. The phase difference between the high-frequency signal that is reflected and leaks to the first dielectric line 1 and the high-frequency signal that leaks from the second dielectric line 2 to the first dielectric line 1 are just reversed in phase. Can do. For this purpose, the line length of the third dielectric line 3 may be set to (2n + 1) / 4 · λg + L corrected from (2n + 1) / 4 · λg.

  In the first isolator of the present invention, each phase change corresponding to the breakdown of L is individually measured and added to obtain L, and finally (2n + 1) / 4 · λg + L is obtained. Instead, as a simpler method, the phase difference δ is measured, and the line length of the third dielectric line 3 is set so that the phase difference δ becomes δ = (2N + 1) · π. Specifically, the line length of the third dielectric line 3 can be set as follows.

  First, the line length of the third dielectric line 3 is set to (2n + 1) / 4 · λg, and the input end (the other end) of the first dielectric line 1 and the output of the second dielectric line 2 are set. A test terminal of the network analyzer is connected to each end (the other end), and the transmission characteristics of the high-frequency signal transmitted from the second dielectric line 2 to the first dielectric line 1 are measured. Next, the length of the third dielectric line 3 is changed from the initially set length, and some of the lengths are different from the second dielectric line 2 to the first dielectric. The transmission characteristic of the high-frequency signal transmitted through the body line 1 is measured by the same method. Then, the measured value of the transmission characteristic is plotted on a diagram as shown in FIG. 2 with the vertical axis as the transmission characteristic and the horizontal axis as the line length of the third dielectric line 3, and the measured value overlaps the plot. Thus, an approximate curve of A · cos θ is drawn, and from the minimum value of this curve, the line length (2n + 1) / 4 · λg + L of the third dielectric line 3 in which the phase difference δ is δ = (2N + 1) · π is obtained. Read it. If it does in this way, it will leak into the 3rd dielectric line 3 from the 2nd dielectric line 2, will reflect through the 3rd dielectric line 3, and will be reflected by the non-reflection terminator 5, and will return. The phase difference between the high-frequency signal leaking to the line 1 and the high-frequency signal leaking from the second dielectric line 2 to the first dielectric line 1 can be exactly set to the opposite phase. Thereby, the isolation characteristic can be made better than before.

Next, components of the first isolator of the present invention will be described in detail. In the first isolator of the present invention, the first, second, and third dielectric lines 1, 2, and 3 are made of resin such as tetrafluoroethylene and polystyrene, or cordierite having a low relative dielectric constant. Ceramics such as (2MgO · 2Al ₂ O ₃ · 5SiO ₂ ) ceramics, alumina (Al ₂ O ₃ ) ceramics, and glass ceramics are preferable, and these have low loss in the millimeter wave band.

  The first, second, and third dielectric lines 1, 2, and 3 are basically rectangular in cross section, but may be rounded at the corners of the rectangle. Various cross-sectional shapes used for transmission can be used.

The ferrite plate 4 is preferably made of zinc / nickel / iron oxide (Zn _a Ni _b Fe _c O _x ), for example, for millimeter wave signals among ferrites.

  In addition, the shape of the ferrite plate 4 is usually a disc shape, but the planar shape may be a regular polygonal shape. In that case, when the number of dielectric lines to be connected is n (n is an integer of 3 or more), the planar shape is preferably a regular m-square (m is an integer greater than n of 3 or more).

  In addition, the non-reflective terminator 5 has a film-like shape on the upper and lower ends of the side surfaces (surfaces not facing the inner surface of a parallel plate conductor (not shown)) with respect to the other end of the third dielectric line 3. What is necessary is just to comprise a resistor or a radio wave absorber. At that time, the material of the resistor is preferably a nickel chromium alloy or carbon. In addition, as the material of the radio wave absorber, permalloy or sendust is suitable. If these materials are used, a high frequency signal can be attenuated efficiently. Moreover, you may use the thing which can attenuate a high frequency signal by materials other than these.

  In addition, the material of the parallel plate conductor (plate conductor) is Cu, Al, Fe, Ag, Au, Pt, SUS (stainless steel), brass (Cu—) in terms of high electrical conductivity and good workability. A conductive plate such as a Zn alloy is suitable. Or what formed these conductor layers on the surface of the insulating board which consists of ceramics, resin, etc. may be used.

  Thus, according to the first isolator of the present invention, it is possible to provide a circulator type isolator for high frequency signals with improved isolation characteristics.

  In addition, this invention is not limited to the example of the above embodiment, It does not interfere in various ways within the range which does not deviate from the summary of this invention. For example, the strength of the high-frequency signal leaking from the second dielectric line 2 to the first dielectric line 1 via the second connection 4b, the ferrite plate 4 and the first connection 4a, and the third dielectric Non-reflective termination so that the intensity of the high-frequency signal leaking from the body line 3 to the first dielectric line 1 through the third connection part 4c, the ferrite plate 4 and the first connection part 4a is comparable. The resistance value of the device 5 may be shifted from the characteristic impedance of the third dielectric line 3. In this case, the two high-frequency signals having opposite phases leaking to the first dielectric line 1 have the same strength and cancel each other more effectively, so that the isolation characteristic is further improved. Become.

  Next, the second isolator of the present invention will be described in detail with reference to the drawings.

  FIG. 3 is a schematic plan view showing an example of an embodiment of the second isolator of the present invention. 3, 205 and 206 are ferrite plates as magnetic materials, 207 and 208 are microstrip lines as first transmission lines, 209 and 210 are microstrip lines as second transmission lines, and 211 and 212, respectively. Are microstrip lines as third transmission lines, 213 and 214 are ground conductors, and 215 and 216 are termination resistors as non-reflection terminators, respectively.

  An example of an embodiment of the second isolator of the present invention is as shown in a plan view in FIG. 3, as microstrip lines 207 and 208 as first transmission lines for transmitting a high-frequency signal, as second transmission lines. The microstrip lines 209 and 210 and the microstrip lines 211 and 212 as third transmission lines are radially connected to the peripheral portions of the ferrite plates 205 and 206 as magnetic bodies, respectively. The first and second circulators C1 and C2 are connected at the connection portions 205b and 206b and the third connection portions 205c and 206c, and output a high-frequency signal input from one connection portion from one of the other adjacent connection portions. C2 is provided by connecting the second microstrip line 209 of the first circulator C1 so that it also serves as the first microstrip line 208 of the second circulator C2. In addition, a non-reflective terminator is provided at the other end of the third microstrip lines 211 and 212 having one ends connected to the third connecting portions 205c and 206c of the first and second circulators C1 and C2, respectively. In the isolator to which the terminating resistors 215 and 216 are connected, the high-frequency signal transmitted from the first microstrip line 207 of the first circulator C1 to the second microstrip line 209 and the second microstrip line 209 The frequency dependence of the isolation characteristic from the high frequency signal transmitted to one microstrip line 207, the high frequency signal transmitted from the first microstrip line 208 of the second circulator C2 to the second microstrip line 210, and the first A high-frequency signal transmitted from the second microstrip line 210 to the first microstrip line 208 And the frequency dependence of the source configuration characteristics are different configurations.

  However, in the first and second circulators C1 and C2, high frequency signals are respectively transmitted from the first microstrip lines 207 and 208 to the second microstrip lines 209 and 210, and from the second microstrip lines 209 and 210, respectively. Transmission to the third microstrip lines 211 and 212 in the forward direction (in this example, the counterclockwise direction from the top) in order from the third microstrip lines 211 and 212 to the first microstrip lines 207 and 208 To be. In addition, as an isolator formed by connecting the first and second circulators C1 and C2, a high-frequency signal input to the input end 207a of the first microstrip line 207 of the first circulator C1 is used as the second circulator. The output is made from the output end 210a of the second microstrip line 210 of the circulator C2.

  In this configuration, each of the microstrip lines 207 to 212 includes a strip conductor formed on the surface of a dielectric substrate (not shown) and a ground conductor (not shown) formed on the back surface of the dielectric substrate. The ground conductor and the ground conductors 213 and 214 are connected by a through conductor (not shown) penetrating the dielectric substrate, and the terminating resistors 215 and 216 are connected to the ground conductors 213 and 214 and the third micro-conductor. What is necessary is just to connect between the ends of the strip conductors of the strip lines 211 and 212. In addition, each microstrip line 207 to 212 is set to a predetermined characteristic impedance such as 50Ω in advance by adjusting the dielectric constant and thickness of the dielectric substrate or the width of the strip conductor, and the termination resistors 215, The resistance value of 216 may be a resistance value matching this characteristic impedance.

  The material used for the dielectric substrate of each of the microstrip lines 207 to 212 is preferably quartz, sapphire, ceramics, epoxy, glass epoxy, ethylene tetrafluoride or the like having a high resistivity and a low dielectric loss tangent. When an isolator is formed as one of circuit elements on a microwave monolithic integrated circuit (MMIC), a III-V group such as gallium arsenide (GaAs) is used instead of the dielectric substrate. A compound semiconductor substrate may be used. The material of the strip conductor and ground conductor of each of the microstrip lines 207 to 212 is a metal having excellent conductivity, such as copper (Cu), gold (Au), silver (Ag), titanium (Ti), and aluminum. (Al) or the like may be used. For the termination resistors 215 and 216, for example, a thin film resistor made of tantalum nitride (TaN) can be suitably used. In this way, the high frequency signal transmitted to the third microstrip lines 211 and 212 can be satisfactorily terminated so as not to be reflected by the termination resistors 215 and 216.

Further, the ferrite plates 205 and 206 may be placed at the center of the region surrounded by the end portions of the strip conductors of the microstrip lines 207 to 212 arranged in a radial pattern. In order to make the frequency dependence of the isolation characteristic different between the first circulator C1 and the second circulator C2, the material, size, thickness or shape of the two ferrite plates 205 and 206 are used. Should be different. As a material of the ferrite plates 205 and 206, among ferrite, for example, zinc / nickel / iron oxide (Zn _a Ni _b Fe _c O _x ) is preferable. Further, the ferrite plates 205 and 206 may have a regular polygonal shape such as a disc shape or a planar shape (a shape in plan view). When the planar shape is a regular polygonal shape, the number of transmission lines to be connected is three, and the planar shape may be a regular triangle or a regular m-gon (m is an integer of 3 or more). In this way, it is possible to control only the frequency dependence of the isolation characteristics without affecting the transmission characteristics of the microstrip lines 207 to 212.

  In addition to this method, the widths of the strip conductors of the microstrip lines 207 to 212 may be different between the first circulator C1 and the second circulator C2. It is necessary to consider that the characteristic impedance of the strip lines 207 to 212 having different strip conductor widths changes and the transmission characteristics of the high-frequency signal change.

  In the above configuration, preferably, the lengths of the third microstrip lines 211 and 212 are reflected by the terminal resistors 215 and 216 through the third microstrip lines 211 and 212, and returned to the first microstrip lines 211 and 212, respectively. A part of the high-frequency signal leaked to the microstrip lines 207 and 208 is defined as Wa, and the first microstrip lines 207 and 208 are passed from the second microstrip lines 209 and 210 via the first and second circulators C1 and C2. Δ = (2N + 1) · π (where N is an integer), where Wb is a part of the other high-frequency signal leaked to δ and δ is a phase difference at the center frequency between these Wa and Wb. It is good to set so that

To set in this way, transmission of a high-frequency signal transmitted from the output end 210a of the second microstrip line 210 of the second circulator C2 to the input end 207a of the first microstrip line 207 of the first circulator C2 is performed. the line length of the third microstrip line 211 and 212 may be adjusted so that the characteristic S ₂₁ is minimized.

  In the above configuration, preferably, in the first and second circulators C1 and C2, the second microstrip line 209 of the first circulator C1 also serves as the first microstrip line 208 of the second circulator C2. It is good to be connected by.

The isolator shown in FIG. 3 configured as described above operates as follows. The high-frequency signal input to the input terminal 207a receives the first microstrip line 207, the second microstrip line 209 (the first microstrip line 208 of the second circulator C2) and the second microstrip line 207 of the first circulator C1. The light passes through the second microstrip line 210 of the circulator C2 in order and is output from the output terminal 210a. Conversely, the high-frequency signal that has been returned to the output terminal 210a from the outside by reflection or the like is input to the second microstrip line 209 of the first circulator C1 (the first microstrip line of the second circulator C2). 208) through the second circulator C2, a part of the light is reflected by the terminating resistor 216 and from the third microstrip line 212, and the other part from the second microstrip line 210, respectively, Wa and Wb. is input as Wa _2, Wb ₂ is further high-frequency signal inputted to the second microstrip line 209 (first microstrip line 208), the second microstrip line 209 (first micro The strip line 208) is partially reflected by the terminating resistor 215 via the first circulator C1, and is reflected from the third microstrip line 211, Some of the second microstrip line 209 (first microstrip line 208), are inputted respectively Wa, as _Wa 1, Wb ₁ is Wb.

At that time, the frequency dependency of Wa ₁ + Wb _{1 and} the frequency dependency of Wa ₂ + Wb ₂ are different from each other due to the above configuration. Therefore, the frequency bandwidth and Wa ₂ + Wb ₂ where Wa ₁ + Wb ₁ becomes small are Since a high frequency signal returning to the input terminal 207a side can be suppressed in a wide frequency band from a combination of two attenuation characteristics different from the frequency bandwidth that becomes smaller, a frequency bandwidth that ensures isolation greater than or equal to a predetermined value can be obtained. Can be wide.

Furthermore, regardless of the change in the phase of the high-frequency signal when the high-frequency signal is reflected by the termination resistors 215 and 216, Wa ₁ and Wb ₁ are just in opposite phases and effectively weakened together. with the waves, Wa ₂ and the Wb ₂ is, since the multiplexed destructively effectively becomes just opposite phase, it is possible to further increase the isolation.

  Therefore, since the example of the second isolator according to the present invention shown in a plan view in FIG. 3 has the above-described configuration, the first isolator can be isolated without being biased to a specific frequency. And the second circulators C1 and C2 are set to different values to obtain the maximum isolation frequency, and the first and second circulators C1 and C2 have a frequency bandwidth in which isolation of a predetermined value or more is secured. Compared to the case where the maximum isolation frequency is set to be the same, the frequency can be increased.

  The line lengths of the third microstrip lines 211 and 212 are reflected by the terminal resistors 215 and 216 through the third microstrip lines 211 and 212 and returned to the first microstrip lines 207 and 208, respectively. A part of the leaked high-frequency signal is set to Wa, and the other part leaked from the second microstrip lines 209 and 210 to the first microstrip lines 207 and 208 via the first and second circulators C1 and C2. Is set to be δ = (2N + 1) · π where δ is a phase difference at the center frequency between Wa and Wb, and the phase difference δ between Wa and Wb is δ. = (2N + 1) · π, so that when the high-frequency signal is reflected by the terminating resistors 215 and 216, the phase advance of the high-frequency signal changes, but leaks to the first microstrip lines 207 and 208 Above One of a portion of the high frequency signal to ensure just opposite phases, since it is possible to effectively so each other are canceled, it is possible to improve the isolation characteristics.

  When the first and second circulators C1 and C2 are connected by the second microstrip line 209 of the first circulator C1 also serving as the first microstrip line 208 of the second circulator C2. The isolator can be configured in a small size.

  In the second isolator of the present invention, as the first, second and third transmission lines, in addition to such a microstrip line, a strip line, a coplanar line, a grounded coplanar line, a slot line, a conductor A wave tube, a dielectric waveguide, or the like may be used.

  Next, for the first high-frequency oscillator of the present invention and the first and second high-frequency transceivers of the present invention, a millimeter wave oscillator as a high-frequency oscillator and a millimeter-wave radar module as a high-frequency transceiver using the same are taken as examples. This will be described in detail below.

  FIG. 4 is a plan view showing a millimeter wave oscillator O which is an example of an embodiment of the first high frequency oscillator of the present invention. FIGS. 5 and 6 are plan views showing millimeter wave radar modules R1 and R2, which are examples of embodiments of the first and second high-frequency transceivers of the present invention, respectively.

First, the main configuration and operation of a millimeter wave oscillator O which is an example of an embodiment of the first high frequency oscillator of the present invention will be described. In FIG. 4, the millimeter wave oscillator O includes an inner surface of the parallel plate conductor 20 between the parallel plate conductors 20 (the other is not shown) arranged at intervals of one half or less of the wavelength of the millimeter wave signal W ₁ . The two ferrite plates 21a and 21b (21b is arranged below 21a) and the two ferrite plates 21a and 21b arranged radially to each other. The input dielectric line 22 for inputting the wave signal W ₁ , the terminating dielectric line 24 provided with a non-reflective termination 23 at the tip, and the millimeter wave signal W ₁ input to the input dielectric line 22 are output Similarly, the first circulator A provided with the output dielectric line 25a and two ferrite plates 26a and 26b (26b on the lower side of 26a) arranged opposite to each other on the inner surface of the parallel plate conductor 20 And substantially free from the two ferrite plates 26a and 26b. Disposed morphism form, is input to the input dielectric guide 25b, non-reflective terminator 27 terminating provided with dielectric line 28 and the input dielectric line 25b to the tip to enter a millimeter-wave signal W ₂ And a second circulator B provided with an output dielectric line 29 for outputting a millimeter wave signal, and the first circulator A and the second circulator B are connected to each other. 25a is connected by an input / output dielectric line 25 which also serves as an input dielectric line 25b. Also, is connected to the voltage controlled oscillator 30 to an input terminal 22a of millimeter wave signal W ₁ of the input dielectric guide 22 is input, it outputs dielectric from the input dielectric guide 22 of the first circulator A in a direction opposite to that of the millimeter-wave signal W ₁₂ that transmits to the line 25a with respect thereto, i.e. the frequency dependency of the isolation characteristics of the millimeter wave signal W ₂₁ that transmits the output dielectric line 25a to the input for the dielectric guide 22 , in the opposite direction thereto and millimeter-wave signal W ₂₃ which transmits from the input dielectric guide 25b of the second circulator B to the output dielectric waveguide 29, i.e. transmission from the output dielectric guide 29 to the input for the dielectric guide 25b The frequency dependency of the isolation characteristic from the millimeter wave signal W ₃₂ is different. The output dielectric line 25a also serves as the input dielectric line 25b. Hereinafter, the output dielectric line 25a may be described as the input / output dielectric line 25 as the same. In FIG. 4, the ferrite plates 21b and 26b are disposed below and in parallel with the ferrite plates 21a and 26a, respectively.

The isolation characteristics in the high-frequency oscillator of the present invention, in one example of this embodiment, as shown in isolation I ₂ follows the first circulator A isolation I ₁ or the second circulator B of Defined.

I ₁ = −10 · log (P ₂₁ / P ₁₂ )
I ₂ = −10 · log (P ₃₂ / P ₂₃ )
However, P ₂₁ , P ₁₂ , P ₃₂ and P ₂₃ are the powers of the millimeter wave signals W ₂₁ , W ₁₂ , W ₃₂ and W ₂₃ , respectively.

  In the configuration of the high frequency oscillator shown in FIG. 4, the voltage controlled oscillator 30 has the same configuration as the voltage controlled oscillator V shown in FIG. The two ferrite plates 21a and 21b of the circulator A and the two ferrite plates 26a and 26b of the circulator B are arranged so that their main surfaces are parallel and concentrically opposed to the inner surface of the parallel plate conductor 20. These main surfaces may be in contact with the inner surface of the parallel plate conductor 20, or may be installed at a predetermined interval from the inner surface of the parallel plate conductor 20. In the example shown in FIG. 4, the main surfaces of the two ferrite plates 21a and 21b or the two ferrite plates 26a and 26b, the input dielectric lines 22, 25b, the output dielectric lines 25a, 29, and the termination The main surfaces of the dielectric lines 24 and 28 are flush with each other, and are in contact with the inner surface of the parallel plate conductor 20. The shape of these ferrite plates 21a, 21b, 26a, 26b is usually a disc shape, but may also be a plate-like regular polygonal column shape whose planar shape is a regular polygon. In that case, since the number of dielectric lines to be connected is three, the planar shape is preferably a regular m square (m is an integer of 3 or more).

The input dielectric lines 22, 25b, the output dielectric lines 25a, 29, and the termination dielectric lines 24, 28 are made of resin such as ethylene tetrafluoride and polystyrene, or a cordier having a low relative dielectric constant. Ceramics such as light (2MgO · 2Al ₂ O ₃ · 5SiO ₂ ) ceramics, alumina (Al ₂ O ₃ ) ceramics, and glass ceramics are preferable, and these have low loss in a high frequency band.

  The parallel plate conductor 20 for the NRD guide is made of Cu, Al, Fe, Ag, Au, Pt, SUS (stainless steel), brass (Cu—Zn alloy) in terms of high electrical conductivity and good workability. A conductive plate such as) is suitable. Or what formed these conductor layers on the surface of the insulating board which consists of ceramics, resin, etc. may be used.

  The line length of the input / output dielectric line 25 is such that the millimeter wave signal directly reflected by the connecting portion between the first circulator A and the input dielectric line 22, the first circulator A and the second circulator A It is preferable to set the length such that the millimeter wave signal that has been multiple-reflected with the circulator B is combined in antiphase. As a result, it is possible to prevent the millimeter wave signal that has been multiple-reflected between the first circulator A and the second circulator B from leaking to the input dielectric line 22, and the overall isolation of the two-stage circulator can be reduced. It will be good.

The main operation of the millimeter wave oscillator O which is an example of the embodiment of the first high frequency oscillator of the present invention is as follows. Millimeter-wave oscillator O is first millimeter wave signals W ₁ generated by the voltage controlled oscillator 30, the input dielectric line 22 of the first circulator A propagates, a millimeter-wave signal from the output dielectric guide 25a It is output as W _2. Next, the millimeter wave signal W ₂ propagates through the input dielectric line 25 b of the second circulator B and is output from the output dielectric line 29 as the millimeter wave signal W ₃ . Finally, it is taken out from the output end 29a of the output dielectric line 29 as a millimeter wave oscillation output. At this time, a part of the millimeter-wave oscillation output is reflected and returned from another millimeter-wave circuit connected to the output terminal 29a, and is input again to the millimeter-wave oscillator O from the output terminal 29a as a return millimeter-wave signal. The return millimeter-wave signal is guided from the output dielectric lines 29 and 25a to the terminating dielectric lines 28 and 24, respectively, and is mostly absorbed by the non-reflective terminators 27 and 23 and terminated. However, it leaks directly from the output dielectric line 29 to the input dielectric line 22 or is not completely terminated by the non-reflective terminators 27 and 23, but is partially reflected, and the termination dielectric lines 27 and 23 are again connected. A part of the return millimeter-wave signal that has propagated and leaked to the input dielectric line 22 or returned from both paths is input to the voltage-controlled oscillator 30 with a slight amount.

Even if this return millimeter wave signal is very small, it may interfere with normal oscillation of the voltage controlled oscillator 30, so that it is attenuated above a predetermined value in the operating frequency band. The frequency at which the isolation I ₁ or the isolation I ₂ is maximized is adjusted. That is, the frequency dependence of the isolation I _{1 and} the frequency dependence of the isolation I ₂ are adjusted so that the frequency band in which the isolation of a predetermined value or more is ensured covers the operating frequency band most widely.

In the first high-frequency oscillator of the present invention, the frequency dependence of the isolation I _{1 and} the frequency dependence of the isolation I ₂ are set to be different. As a result, when the frequency dependence of the isolation I _{1 and} the frequency dependence of the isolation I ₂ is the same as the frequency bandwidth in which the isolation I ₁ + I ₂ that is the combined isolation is equal to or greater than a predetermined value. Therefore, the voltage controlled oscillator 30 can oscillate stably over a wide frequency range, and the millimeter wave oscillator O operates stably.

  In the high-frequency oscillator of the present invention, the predetermined value or more is, for example, a value of 30 dB or more in total by two circulators. If this value is less than 30 dB, the isolation is small, so that, for example, when oscillating at a high output, the returning millimeter wave signal is not sufficiently suppressed, and the oscillation of the millimeter wave oscillator becomes unstable. When incorporated in a radar module, there is a possibility that radar detection cannot be performed or erroneous detection occurs.

  Next, a more detailed configuration and operation of the millimeter wave oscillator O which is an example of an embodiment of the first high frequency oscillator of the present invention will be described.

  The high frequency band referred to in the high frequency oscillator of the present invention corresponds to a microwave band and a millimeter wave band of several tens to several hundreds GHz, and for example, a high frequency band of 30 GHz or higher, particularly 50 GHz or higher, and further 70 GHz or higher is preferable. In particular, 76 to 77 GHz is preferable. In this case, when the high frequency oscillator of the present invention is used for a high frequency transceiver such as a millimeter wave radar module for automobiles having an operating frequency of about 76 to 77 GHz, the oscillation frequency of the high frequency oscillator is Even if the temperature changes, a high transmission characteristic of a high frequency signal can be obtained in a wide band.

Further, as means for setting the frequency dependency of the isolation I _{1 and} the frequency dependency of the isolation I ₂ to be different, specifically, at least one of the interval and the dimension between the two ferrite plates 21a and 21b. And at least one of the interval and size of the two ferrite plates 26a and 26b corresponding to them, the end portions of the input dielectric lines 22 and 25b on the ferrite plate 21a and 21b side and the output dielectric The center of the region surrounded by the ends of the lines 25a, 29 on the ferrite plates 21a, 21b side and the ends of the terminating dielectric lines 24, 28 on the side of the ferrite plates 21a, 21b, and the centers of the ferrite plates 21a, 21b And ferrite plates 21a, 21b, 26a, 26b may be attached. Accordingly, the positioning of the ferrite plates 21a, 21b, 26a, 26b is easy because it can be performed by positioning only one point, and by attaching the ferrite plates 21a, 21b, 26a, 26b to the correct positions. In addition, it is possible to determine the frequency dependence while eliminating the characteristic variation factor due to the positional deviation at the time of assembly, and to deteriorate the transmission characteristics from the input dielectric lines 22 and 25b to the output dielectric lines 25a and 29. The frequency dependence can be set and adjusted without any problem, so that fine adjustment of the frequency dependence can be easily and reliably performed, and the frequency at which the first circulator A and the second circulator B obtain the maximum isolation can be determined. By setting different values, the first and second circulators will maximize the frequency bandwidth that ensures the isolation above a predetermined value. Compared to the case where the isolation frequency is set to the same value, it can be easily and reliably widened, so that the millimeter-wave signal returning to the high-frequency oscillator in a wide frequency range is sufficiently suppressed to oscillate stably. Will be able to. Further, when the operating frequency range is limited, the effect that the predetermined value of the isolation to be secured can be set higher than in the case where the frequencies at which the first and second circulators obtain the maximum isolation are set to be the same. Even when an unstable factor such as a pulse of the millimeter wave signal returning to the high-frequency oscillator is applied, the oscillation is more stable than when a characteristic variation factor due to misalignment during assembly is added. Will be able to.

  In addition, after assembly, the ferrite plates 21a, 21b, 26a, and 26b can be easily replaced with another one while suppressing the characteristic variation factor during assembly by the same method. By changing 21a, 21b, 26a, 26b, the isolation characteristics can be easily changed and adjusted.

As another means for setting the frequency dependency of the isolation I _{1 and} the frequency dependency of the isolation I ₂ to be different, in the millimeter wave oscillator O, the ferrite plates 21a and 21b and the ferrite plates 26a and 26b The material or magnetization may be different. In this case, this means can be used as an auxiliary adjustment means for adjusting the frequency dependency together with the above, in addition to performing the same adjustment as described above. This another means is, for example, in the operating frequency range when the isolation characteristic of either circulator A or circulator B is shifted in parallel to the frequency axis by adjusting the dimensions or arrangement interval of ferrite plates 21a and 21b. It can also be used to correct isolation degradation.

As still another means for setting the frequency dependency of the isolation I _{1 and} the frequency dependency of the isolation I ₂ to be different, in the millimeter wave oscillator O, the input dielectric lines 22 and 25b and the output dielectric Any of the dimensions or materials of the body lines 25a and 29 may be different.

When setting the frequency dependence of the isolation I _{1 and} the frequency dependence of the isolation I ₂ to be different, if one condition is changed independently and the isolation characteristic is shifted in parallel with the frequency axis, In such a case, the above-described plurality of conditions may be appropriately combined and set.

  Next, an example of the embodiment of the millimeter wave radar module as the first and second high-frequency transceivers of the present invention will be described below.

  FIGS. 5 and 6 show examples of the embodiments of the millimeter wave radar modules R1 and R2 as the first and second high-frequency transceivers according to the present invention, respectively. FIG. FIG. 6 is a plan view of the integrated transmission antenna and the reception antenna.

  The millimeter wave radar module R1 shown in FIG. 5 includes a first plate between parallel plate conductors 40 (the other is not shown) disposed at intervals of 1/2 or less of the wavelength of the millimeter wave signal for transmission. A millimeter wave signal oscillating unit 42 which is attached to the dielectric line 41 and modulates the frequency of the high frequency signal output from the high frequency diode and propagates the first dielectric line 41 as a millimeter wave signal, and the first dielectric line 41 And one end side of the first dielectric line 41 is electromagnetically coupled to a pulse modulator 43 that pulsates the millimeter wave signal and outputs it as a millimeter wave signal for transmission from the first dielectric line 41. Or a second dielectric that propagates a part of the millimeter-wave signal input to the first dielectric line 41 to the mixer 51 side. A body track 44 is provided.

  In addition, ferrite plates 45a and 45b (45b is arranged on the lower side of 45a) arranged in parallel to the parallel plate conductor 40 are arranged at predetermined intervals and input / output of millimeter wave signals, respectively. The first connection portion 46a, the second connection portion 46b, and the third connection portion 46c are connected to each other, and the millimeter wave signal input from any one of the connection portions is converted into the ferrite plates 45a and 45b. The circulator C outputs from another connection portion adjacent in the clockwise direction or the counterclockwise direction within the plane of the first, and the first connection portion 46a is connected to the output end of the millimeter wave signal of the first dielectric line 41. Circulator C, a third dielectric line 48 connected to the second connection portion 46b of the circulator C to propagate a millimeter wave signal and having a transmitting / receiving antenna 47 at the tip, and a third connection portion of the circulator C It is connected to 46c and received by the transmitting / receiving antenna 47. A fourth dielectric line 50 that propagates through the third dielectric line 48 and propagates the received wave output from the third connection 46c to the detector 49 of the mixer, and a second dielectric line 44. The middle wave and the middle of the fourth dielectric line 50 are close to each other or joined so as to be electromagnetically coupled, and the millimeter wave signal inputted from the second dielectric line 44 and the fourth dielectric line 50 are combined. A mixer 51 for generating an intermediate frequency signal by mixing the millimeter wave signal input from the signal, and a non-reflection terminator 52 connected to the opposite end of the mixer 51 of the second dielectric line 44 It has been.

  Then, the millimeter wave radar module R1 as an example of the embodiment of the first high frequency transmitter / receiver of the present invention includes a millimeter wave oscillator O shown in FIG. 4 in which the millimeter wave signal oscillator 42 is the high frequency oscillator of the present invention. It consists of

  As an example of the embodiment of the millimeter wave radar module as the second high-frequency transmitter / receiver of the present invention, there is a type shown in a plan view in FIG. 6 in which a transmitting antenna and a receiving antenna are made independent.

  The millimeter wave radar module R2 shown in FIG. 6 has a first plate between parallel plate conductors 60 (the other is not shown) arranged at intervals of 1/2 or less of the wavelength of the millimeter wave signal for transmission. A millimeter-wave signal oscillating unit 62 that is attached to the dielectric line 61 and modulates the high-frequency signal output from the high-frequency diode and propagates the first dielectric line 61 as a millimeter-wave signal, and the first dielectric line 61 And one end side of the first dielectric line 61 is electromagnetically coupled to a pulse modulator 63 that pulsates the millimeter wave signal and outputs it as a millimeter wave signal for transmission from the first dielectric line 61. Or a second dielectric that propagates a part of the millimeter-wave signal input to the first dielectric line 61 to the mixer 74 side. A body track 64 is provided.

  In addition, ferrite plates 65a and 65b (65b is arranged on the lower side of 65a) arranged in parallel to the parallel plate conductor 60 are arranged at predetermined intervals, and each input / output of a millimeter wave signal. The first connection portion 66a, the second connection portion 66b, and the third connection portion 66c, which are the ends, have a millimeter wave signal input from any one of the connection portions as ferrite plates 65a and 65b. A circulator D that outputs from the other connection part adjacent in the clockwise or counterclockwise direction in the plane of the first dielectric line 61, and the first connection part 66a is connected to the output end of the millimeter wave signal of the first dielectric line 61. Connected to the second connection portion 66b of the circulator D, a third dielectric line 68 that propagates the millimeter wave signal and has the transmitting antenna 67 at the tip portion, and a receiving antenna 69 at the tip portion, A mixer detector 70 is provided at the other end. 4 is connected to the dielectric line 71 of the circulator 4 and the third connection part 66c of the circulator D, and the millimeter wave signal received and mixed by the transmitting antenna 67 is propagated, and the non-reflective terminator 72 provided at the tip part transmits the millimeter wave signal. The second dielectric line 73, the middle part of the second dielectric line 64, and the middle part of the fourth dielectric line 71 are close to each other or joined so as to be electromagnetically coupled to each other. A mixer 74 for mixing the millimeter wave signal input from the dielectric line 64 and the millimeter wave signal input from the fourth dielectric line 71 to generate an intermediate frequency signal, and a mixer for the second dielectric line 64 An anti-reflection terminator 75 connected to the opposite end of 74 is provided.

  The millimeter wave radar module R2 as an example of the second high frequency transceiver according to the present invention includes a millimeter wave oscillator O shown in FIG. 4 in which the millimeter wave signal oscillator 62 is the high frequency oscillator of the present invention. It consists of

  These millimeter wave radar modules R1 and R2 operate as radars for detecting a target as described below. First, the millimeter wave signals for transmission generated by the millimeter wave signal oscillating units 42 and 62 are further pulse-modulated by the pulse modulators 43 and 63, and then transmitted from the transmission / reception antenna 47 or the transmission antenna 67 toward the target. Next, the millimeter wave signal reflected by the target is received by the transmission / reception antenna 47 or the transmission antenna 69, and the received millimeter wave signal and the millimeter wave signal for transmission before pulse modulation are mixed by the mixers 51 and 74. (Mixing) to obtain an intermediate frequency output. The distance to the target can be obtained by performing appropriate arithmetic processing on the intermediate frequency output.

  Although these millimeter wave radar modules R1 and R2 constitute a so-called FM pulse type millimeter wave radar, the millimeter wave signal oscillation unit of the millimeter wave radar module uses the first high frequency oscillator of the present invention. Even if a pulse-like return millimeter-wave signal is input from the pulse modulator to the millimeter-wave signal oscillator, the pulse-like return millimeter-wave signal is sufficient in the wide frequency range of the millimeter-wave signal generated from the millimeter-wave signal oscillator. Because the isolation of the millimeter wave signal oscillation unit is high, even if the fluctuation of the oscillation frequency of the millimeter wave signal oscillation unit is large, the variation due to the environmental temperature is large, or the transmission output is high. However, stable millimeter wave transmission with less noise can be reliably performed.

  Further, according to these millimeter wave radar modules R1 and R2, the return millimeter wave signal input to the millimeter wave signal oscillating unit is sufficiently attenuated even in a method that does not include a pulse modulator as a component, that is, Since the millimeter-wave signal oscillator has high isolation, stable millimeter-wave transmission can be performed even when the transmission output is high. For example, even if the target is far away, millimeter-wave transmission / reception can be reliably performed. It will be a thing.

What is important in the first and second high-frequency transceivers of the present invention and the first high-frequency oscillator of the present invention used therefor is that the frequency dependency of the isolation I _{1 and} the frequency dependency of the isolation I ₂ are the same. Therefore, the frequency bandwidth in which the isolation I ₁ + I ₂ , which is their combined isolation, is equal to or greater than a predetermined value is set to the frequency dependence of the isolation I ₁ and the isolation I ₂ . This is because the frequency dependence can be made wider than when the frequency dependence is the same. Next, this will be described in an embodiment.

  The millimeter wave oscillator O shown in FIG. 4 was configured as follows. First, two Al plates having a thickness of 6 mm are arranged as parallel plate conductors 20 with an interval a = 1.8 mm, and two ferrite plates having a diameter of 2 mm and a thickness of tmm described later are placed between them. One of 21a and 21b is in close contact with the upper flat conductor and the other is in close contact with the lower flat conductor, and the central axes thereof are arranged on the same straight line so as to face each other. An input dielectric made of cordierite ceramics having a radial cross section of 1.8 mm (height) x 0.8 mm (width) and a dielectric constant of 4.8 around the ferrite plates 21a and 21b. The first circulator A was configured by arranging the line 22, the terminating dielectric line 24, and the input / output dielectric line 25. In the first circulator A, the input dielectric line 22, the termination dielectric line 24, and the input / output dielectric line 25 are adjacent to each other in the clockwise direction with the angle formed by the adjacent lines being 120 degrees. The direction of the magnetic field of the ferrite plates 21a and 21b was set so that the matched lines were isolated from each other.

  Similarly, between the parallel plate conductors 20, one of two ferrite plates 26a and 26b having a diameter of 2 mm and a thickness of tmm, which will be described later, is in close contact with the upper plate conductor and the other is in close contact with the lower plate conductor. The central axes are arranged on the same straight line so as to face each other. The ferrite plate 26a, 26b has a rectangular shape with a radial cross section of 1.8 mm (height) x 0.8 mm (width) and a dielectric constant of 4.8 for cordierite ceramics. A dielectric line 25, a terminating dielectric line 28, and an output dielectric line 29 were arranged to constitute a second circulator B. In the second circulator B, the input / output dielectric line 25, the termination dielectric line 28, and the output dielectric line 29 are adjacent to each other in the clockwise direction with the angle formed by the adjacent lines being 120 degrees. The direction of the magnetic field of the ferrite plates 21a and 21b was set so that the matched lines were isolated from each other.

  The ferrite plates 21a, 21b, 26a, and 26b are made of the same material having a relative dielectric constant of 13.5 and a saturation magnetization of 3,300 G (Gauss) (magnetic flux density Bm by JIS C2561 DC magnetic measurement). . Then, the first circulator A and the second circulator B are connected by the input / output dielectric line 25, and the non-reflective termination lines 24, 28 are connected to the end opposite to the ferrite plates 21 a, 26 a side. Reflective terminators 23 and 27 were connected.

Two types of samples were prepared for the circulator, which is a component of the millimeter wave oscillator O configured as described above. One of them is a sample (A) as an example of the present invention, and the other is a sample (B) as a comparative example. In the sample (A), the frequency dependence of the isolation I _{1 and} the frequency of the isolation I ₂ In the sample (b), the frequency dependency of the isolation I _{1 and} the frequency dependency of the isolation I ₂ are set to be the same. Specifically, in the sample (b), the thicknesses of the ferrite plates 21a and 21b and the ferrite plates 26a and 26b are both t = 0.234 mm. In the sample (b), only the thicknesses of the ferrite plates 21a and 21b are sample (b). The thickness of the ferrite plates 26a and 26b is t = 0.231 mm, which is different from that of the sample (b). Samples (A) and (B) were all the same except for the thickness of the ferrite plate.

Then, the isolation characteristics (isolation I ₁ + I ₂ ) of the two stages of the circulator were measured for samples (A) and (B). Further, before connecting the first circulator A and the second circulator B to the sample (A), their respective isolation characteristics (isolation I ₁ , I ₂ ) It was measured. Among them, a sample (c) having a thickness of ferrite plates 21a and 21b or ferrite plates 26a and 26b of t = 0.234 mm is used as a sample (c), and a sample having a thickness of ferrite plates 26a and 26b of t = 0.231 mm (d). It was.

For measurement of the isolation characteristics, a network analyzer for millimeter wave band is used, and in the samples (b) and (b), 75 to 80 GHz isolation I ₁ + I between the input terminal 22a and the output terminal 29a. _2, was measured by connecting the port 1 and port 2 of the network analyzer to the respective inputs 22a and an output terminal 29a. In the samples (c) and (d), the isolations I ₁ and I _{2 at} 75 to 80 GHz between the input ends of the input dielectric lines 22 and 25b and the output ends of the output dielectric lines 25a and 29 are used. Was measured by connecting port 1 and port 2 of the network analyzer to the input end and the output end, respectively. The results are shown in the graph of FIG.

  FIG. 7 is a graph showing the isolation characteristics of the first stage of the first circulator A or the second circulator B constituting the millimeter wave oscillator O. The horizontal axis represents frequency (unit: GHz), and the vertical axis represents isolation. Represents the gain (unit: dB), x plots show typical measured values of sample (c) isolation characteristics, and * plots show typical measured values of sample (d) isolation characteristics. Is shown. FIG. 8 shows the two-stage isolation characteristics of the first circulator A and the second circulator B constituting the millimeter wave oscillator O. The horizontal axis and the vertical axis are the same as those in FIG. The curve shows the representative measured value of the isolation characteristic of the sample (A), and the broken characteristic curve shows the representative measured value of the isolation characteristic of the sample (B).

From the measurement results of the samples (c) and (d) shown in FIG. 7, the thicknesses of the ferrite plates 21a and 21b of the first circulator A and the thicknesses of the ferrite plates 26a and 26b of the second circulator B are set differently. Thus, it can be seen that the frequency dependence of the isolation I ₁ of the first circulator A is different from the frequency dependence of the isolation I ₂ of the second circulator B. That is, in the sample (C), the frequency that takes the maximum value of isolation is 75.9 GHz, whereas in the sample (D), the frequency that takes the maximum value of isolation is 77.4 GHz. The characteristic curves drawn by each plot are also different, and the frequency dependence is different.

Further, based on the measurement results of the samples (A) and (B) shown in FIG. 8, the frequency dependency of the isolation I _{1 and} the frequency dependency of the isolation I ₂ are set to be different from each other, thereby synthesizing them. The frequency bandwidth at which isolation I ₁ + I ₂ that is isolation is 30 dB or more is wider than when the frequency dependency of isolation I _{1 and} the frequency dependency of isolation I ₂ are the same. I understand. That is, in the sample (b) in which the frequency dependence of the isolation I _{1 and} the frequency dependence of the isolation I ₂ are the same, the frequency bandwidth where the isolation I ₁ + I ₂ is 30 dB or more was 3.6 GHz. whereas, in the sample (a) that the frequency dependency of the isolation I ₁ of the frequency dependence and the isolation I ₂ are different, frequency bandwidth isolation I _{1 +} I ₂ is equal to or greater than 30dB is 4.0GHz Thus, it has been confirmed that the frequency bandwidth capable of obtaining an isolation of 30 dB or more determined as a predetermined value of isolation can be widened.

  Next, a voltage-controlled oscillator V as shown in FIGS. 5 and 6 was connected to the input terminal 22a of the samples (A) and (B) to constitute two types of millimeter wave oscillators.

  Then, a millimeter wave radar module as shown in FIG. 5 was configured using a millimeter wave oscillator in which samples (A) and (B) were incorporated, and a millimeter wave transmission / reception test was performed. At this time, in the millimeter wave radar module in which the sample (A) is incorporated, the operation center frequency is set to 77.2 GHz, and the oscillation frequency of the millimeter wave oscillator is changed in a range of ± 2 GHz around 77.2 GHz. Radar module was operated. In the millimeter wave radar module with built-in sample (b), the operation center frequency is set to 76.9 GHz, and the oscillation frequency of the millimeter wave oscillator is changed in the range of ± 2 GHz around 76.9 GHz. Activated the module.

As described above, when two types of millimeter wave radar modules were operated at the same frequency bandwidth at substantially the same operation center frequency, millimeter wave transmission / reception could be stably performed with the sample (A) incorporated. However, when the sample (B) is incorporated, the oscillation of the millimeter wave oscillator becomes unstable, and good millimeter wave transmission / reception may not be performed. In the case where the sample (B) is incorporated, the isolation I ₁ + I ₂ may be 3 dB lower than 30 dB at the maximum in the operating frequency range, whereas the sample (A) is not incorporated. In the operating frequency range, the isolation I ₁ + I ₂ was always 30 dB or more, and it was confirmed that millimeter wave transmission / reception could be performed stably.

  Thus, the millimeter wave radar modules R1 and R2 as examples of the first and second high frequency transceiver embodiments of the present invention have high performance by having the high frequency oscillator of the present invention having high isolation. In addition, the isolation characteristics between the voltage-controlled oscillator and the transmitting / receiving antenna side or the transmitting antenna side are improved over a wider bandwidth. As a result, even if the oscillation frequency of the millimeter-wave signal oscillation unit varies greatly or depending on the environmental temperature Even if the fluctuation is large or the transmission output is high, stable millimeter wave transmission / reception can be reliably performed.

  It should be noted that the present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the scope of the present invention. For example, in the first high-frequency oscillator of the present invention, as a substitute for the first and second circulators composed of two ferrite plates, an input dielectric line, and an output dielectric line, a Faraday rotation type Two stages of isolators, resonance absorption type isolators or electric field displacement type isolators may be used. In that case, it is not necessary to connect a non-reflective terminator to one end like a circulator, and the number of parts is reduced. Assembling becomes easy. Further, the same function can be realized with two terminals, and the device can be configured in a small size.

Further, the ferrite plates 21a and 26a and the ferrite plates 21b and 26b are connected to the end surfaces of the input dielectric line 22, the input / output dielectric line 25, the termination dielectric lines 24 and 28, and the output dielectric line 29. A configuration may be adopted in which the substrate is attached at a fixed interval regulated by the support through the bonded support, and in that case, the isolations I ₁ and I can also be adjusted by adjusting the size and dielectric constant of the support. The frequency dependency of ₂ can be adjusted.

  Next, the second high-frequency oscillator of the present invention and the third and fourth high-frequency transceivers of the present invention will be described in detail with reference to the drawings.

  FIG. 9 is a schematic block circuit diagram showing an example of the embodiment of the third high-frequency transceiver of the present invention. FIG. 10 is a schematic block circuit diagram showing an example of an embodiment of the fourth high-frequency transceiver according to the present invention. 9 and 10, 231 is a high-frequency oscillator, 232 is a branching device, 232a is an input terminal, 232b is one output terminal, 232c is the other output terminal, 233 is a modulator, 234 is a circulator, 234a is an input terminal, 234b is one output terminal, 234c is the other output terminal, 235 is a transmission / reception antenna, 236 is a mixer, 237 is a switch, 238 is an isolator, 239 is a transmission antenna, and 240 is a reception antenna.

  An example of an embodiment of the second high-frequency oscillator of the present invention is one of the first and second isolators 232 of the present invention and a voltage controlled oscillator (VCO) connected to the input terminal 232a of the isolator 232. 231.

  For the connection between the isolator 232 and the voltage controlled oscillator 231, an appropriate transmission line for connection is selected according to the form of the voltage controlled oscillator 231 so that the connection loss is as small as possible. What is necessary is just to connect through this transmission line. For example, in the case of the voltage controlled oscillator 231 configured by MMIC, a planar transmission line such as a microstrip line or a coplanar line is suitable. Further, the transmission line that constitutes the isolator 232 may be the same transmission line as the planar transmission line. In the case of a pill type Gunn diode oscillator, a waveguide or dielectric waveguide is suitable as a transmission line for connection, and a waveguide or dielectric is used as the transmission line constituting the isolator 232. In addition to the body waveguide, a non-radiative dielectric line is suitable. When a nonradiative dielectric line is used as the transmission line of the isolator 232, the electric field of the standing wave in the LSM mode of the dielectric line of the nonradiative dielectric line is opposite to one of the flat conductors of the nonradiative dielectric line. A through hole is provided at a strong location, and one end of a waveguide or dielectric waveguide is connected to the through hole, and a pill type Gunn diode oscillator is connected to the other end of the waveguide or dielectric waveguide. Just connect.

  An example of an embodiment of the second high-frequency oscillator according to the present invention has the above-described configuration, so that the isolator has an excellent isolation characteristic, and thus the isolator returns to the voltage controlled oscillator. Since the high frequency signal is sufficiently attenuated, the high frequency signal can be stably generated with a good oscillation output.

  Next, an example of an embodiment of the third high-frequency transmitter / receiver of the present invention includes a high-frequency oscillator 231 that generates a high-frequency signal and a high-frequency oscillator 231 connected thereto, as shown in a block circuit diagram of FIG. A branching device 232 that branches the high-frequency signal and outputs it to one output terminal 232b and the other output terminal 232c, and a part of the high-frequency signal connected to the one output terminal 232b is modulated to transmit a high-frequency signal. A modulator 233 that outputs as a signal, a first terminal 234a, a second terminal 234b, and a third terminal 234c around the magnetic material, and adjacent high-frequency signals input from one terminal in this order. The circulator 234 having the first terminal 234a connected to the output terminal of the modulator 233 and the high-frequency signal for transmission connected to the second terminal 234b of the circulator 234 are transmitted from the next terminal. Reflected back from the object to be detected A transmission / reception antenna 235 that receives a high-frequency signal received from the transmitter, a high-frequency signal that is connected between the other output terminal 232c and the third terminal 234c of the circulator 234 and that is output to the other output terminal 232c; A mixer 236 that mixes the received high frequency signal and outputs an intermediate frequency signal is provided, and the high frequency oscillator 231 is a configuration as an example of the second high frequency oscillator of the present invention.

  In addition to the above configuration, a switch 237 that opens / closes (switches) the intermediate frequency signal in accordance with an external open / close control signal is preferably provided at the output end of the mixer 236.

  The high frequency transmitter / receiver shown in FIG. 9 operates in the same manner as a conventional high frequency transmitter / receiver, but the isolator provided in the high frequency oscillator 231 returns from the modulator 233 side or the mixer 236 side with high isolation. In order to attenuate the incoming high frequency signal, a part of the transmission high frequency signal pulse-modulated by the modulator 233 is reflected by the circulator 234, the transmission / reception antenna 235, the mixer 236 or others, and the reflected high frequency signal is various. Even when the phase and intensity return to the high-frequency oscillator 231, the high-frequency oscillator 231 can stably generate a high-frequency signal with a good oscillation output, and thus can transmit a high-frequency signal that is easy to identify on the receiving side.

  Further, when a switch 237 that opens and closes (switches) the intermediate frequency signal in response to an open / close control signal from the outside is provided at the output end of the mixer 236, the input end 234a of the circulator 234 is insufficient due to lack of isolation of the circulator 234 or the like. Even if a part of the transmission high-frequency signal leaks to the other output terminal 234c, the switch 237 blocks the intermediate frequency signal so as not to output the intermediate frequency signal corresponding to the leaked high-frequency signal. Therefore, it is possible to further easily identify the high-frequency signal to be received on the receiving side.

  An example of an embodiment of the fourth high-frequency transceiver according to the present invention includes a high-frequency oscillator 231 that generates a high-frequency signal and a high-frequency oscillator 231 that is connected to the high-frequency oscillator 231 as shown in a block circuit diagram of FIG. A branching device 232 for branching a high-frequency signal and outputting it to one output end 232b and the other output end 232c, and modulating a part of the high-frequency signal connected to one output end 232b to transmit a high-frequency signal The output of the modulator 233, one end connected to the output end of the modulator 233, the isolator 238 that transmits the transmission high-frequency signal from one end to the other end, and the isolator 238 A transmitting antenna 239 that transmits a high-frequency signal for transmission, a receiving antenna 240 connected to the other output terminal 232c side of the branching device 232, and the other connected between the other output terminal 232c and the receiving antenna 240 Output to output 232c And a mixer 236 that mixes the high frequency signal received by the receiving antenna 240 and outputs an intermediate frequency signal, and the high frequency oscillator 231 implements the second high frequency oscillator of the present invention. This is an example configuration.

  In addition to the above configuration, a switch 237 that opens / closes (switches) the intermediate frequency signal in accordance with an external open / close control signal is preferably provided at the output end of the mixer 236.

  In the high frequency transmitter / receiver shown in FIG. 10, the isolator included in the high frequency oscillator 231 returns from the modulator 233 side or the mixer 236 side with high isolation, like the high frequency transmitter / receiver shown in FIG. In order to attenuate the high-frequency signal, a part of the transmission high-frequency signal pulse-modulated by the modulator 233 is reflected by the transmission antenna 235 or others, and the reflected high-frequency signal has a high frequency oscillator 231 with various phases and intensities. Since the high frequency oscillator 231 can stably generate a high frequency signal with a good oscillation output even when the signal returns to, it is possible to transmit a high frequency signal that can be easily identified on the receiving side.

  The isolator connected between the modulator 233 and the transmission antenna 239 functions to attenuate the high-frequency signal that returns to the modulator 233 with various phases and intensities, so that the modulator 233 operates stably.

  In addition, when a switch 237 that opens and closes (switches) the intermediate frequency signal in accordance with an external switching control signal is provided at the output end of the mixer 236, the isolation between the transmission antenna 239 and the reception antenna 240 is insufficient. Thus, even if a part of the high-frequency signal for transmission leaks to the receiving antenna 240, the switch 237 blocks the intermediate-frequency signal so that the intermediate-frequency signal for the leaked high-frequency signal is not output. Since it can be operated, it is possible to further easily identify the high-frequency signal to be received on the receiving side.

  In the present invention, the frequency band used as the high-frequency signal is effective not only in the millimeter wave band but also in the microwave band or lower frequency band.

  Next, a radar apparatus according to the present invention, a vehicle equipped with the radar apparatus and a small ship equipped with the radar apparatus will be described.

  The radar apparatus according to the present invention detects distance information to the detection target by processing the high-frequency transceiver according to any one of the first to fourth aspects of the present invention and an intermediate frequency signal output from the high-frequency transceiver. And a distance information detector.

  Since the radar apparatus of the present invention has the above-described configuration, the high-frequency transmitter / receiver transmits a good high-frequency signal that is easy to identify on the receiving side, so that it can quickly and reliably detect the detection target and It is possible to provide a radar apparatus that can reliably detect a far object to be detected.

  A vehicle equipped with a radar apparatus according to the present invention includes the radar apparatus according to the present invention, and the radar apparatus is used for detecting a detection target.

  Since the radar device-equipped vehicle of the present invention has such a configuration, the behavior of the vehicle can be controlled based on the distance information detected by the radar device, For example, the detection of obstacles on the road or other vehicles can be warned by sound, light or vibration. However, in the vehicle equipped with the radar device of the present invention, Since the radar apparatus detects other vehicles 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.

  The radar device-equipped vehicle of the present invention is not limited to a vehicle for transporting passengers and cargo such as trains, trains, and automobiles, but also bicycles, motorbikes, amusement park vehicles, golf courses, etc. It can also be used for carts and the like.

  A small ship equipped with a radar apparatus according to the present invention includes the radar apparatus according to the present invention, and the radar apparatus is used to detect a detection target.

  Since the small ship equipped with the radar apparatus of the present invention has such a configuration, the behavior of the small ship is controlled based on the distance information detected by the radar apparatus in the small ship as in the conventional vehicle equipped with the radar apparatus. 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 a ship, the radar device quickly and reliably detects obstacles such as reefs, other ships or other small ships that are detection objects. Proper control and appropriate warning to the operator can be provided.

  The small-sized ship equipped with the radar device of the present invention is specifically a ship that can be operated without a license for a small ship or a license, and is a boat with a total tonnage of less than 20 tons. Motorcycles, small bass boats with outboard motors, inflatable boats with inboard motors (rubber boats), fishing boats, recreational fishing boats, work boats, houseboats, towing boats, sports boats, fishing boats, yachts, open-sea yachts, cruisers or gross tonnage 20 It can be used for pleasure boats of tons or more.

  Thus, according to the present invention, it is possible to provide an isolator with improved isolation characteristics in a circulator-type isolator in which a non-reflection terminator is connected to one of the input / output transmission lines of the circulator.

  In addition, according to the present invention, it is possible to widen the frequency bandwidth in which isolation of a predetermined value or more is ensured, widen the frequency bandwidth for stable oscillation, and the frequency characteristics of the high-frequency oscillator Therefore, it is possible to provide a high-frequency oscillator that can be stably operated even if it is affected by the operating environment temperature and a high-performance high-frequency transceiver using the same.

  Furthermore, according to the present invention, it is possible to provide a radar apparatus equipped with such a high-performance high-frequency transmitter / receiver, a radar apparatus-equipped vehicle equipped with the radar apparatus, and a radar apparatus-equipped small ship.

It is a typical top view which shows an example of embodiment of the 1st isolator of this invention. FIG. 2 is a diagram showing the dependence of the isolation characteristics on the phase difference δ in the example of the isolator shown in FIG. 1. It is a typical top view which shows an example of embodiment of the 2nd isolator of this invention. It is a top view which shows the millimeter wave oscillator O as an example of embodiment of the 1st high frequency oscillator of this invention. It is a top view which shows millimeter wave radar module R1 as an example of embodiment of the 1st high frequency transmitter-receiver of this invention. It is a top view which shows millimeter wave radar module R2 as an example of embodiment of the 2nd high frequency transmitter-receiver of this invention. It is a graph which shows the representative measured value of the isolation characteristic of 1 step | paragraph of a circulator. It is a graph which shows the typical measured value of the isolation characteristic of two stages of circulators used for the 1st high frequency oscillator of the present invention, and the isolation characteristic of two stages of circulators for the comparison. It is a typical block circuit diagram which shows an example of embodiment of the 3rd high frequency transmitter-receiver of this invention. It is a typical block circuit diagram which shows an example of embodiment of the 4th high frequency transmitter-receiver of this invention. It is a typical fragmentary perspective view which shows the basic composition of a non-radioactive dielectric track | line. It is a typical top view which shows the example of the conventional isolator. It is a perspective view which shows the example of the conventional high frequency oscillator. FIG. 14 is a perspective view showing an example of a wiring board provided with the varactor diode for the high-frequency oscillator of FIG. It is a top view which shows the example of the millimeter wave radar module comprised incorporating the conventional high frequency oscillator.

Explanation of symbols

1: 1st dielectric line 2: 2nd dielectric line 3: 3rd dielectric line 4: Ferrite plate 4a: 1st connection part 4b: 2nd connection part 4c: 3rd connection part 5 : Non-reflective terminator
20: Parallel plate conductor
21a, 21b, 26a, 26b: Ferrite plate
22, 25b: Dielectric line for input
22a: Input end (dielectric line for input)
23, 27: Non-reflective terminator
24, 28: Dielectric lines for termination
25a, 29: Dielectric line for output
29a: Output end (dielectric line for output)
25: Input / output dielectric line (also serves as input dielectric line 25b and output dielectric line 25a)
30: Voltage controlled oscillator
40, 60: Parallel plate conductor
41, 61: First dielectric line
42, 62: Millimeter wave signal oscillator
43, 63: Pulse modulator
44, 64: second dielectric line
45a, 45b, 65a, 65b: Ferrite plate
46a, 66a: first connection part
46b, 66b: second connection part
46c, 66c: third connection part
47: Transmit / receive antenna
48, 68: Third dielectric line
49, 70: Mixer detector
50, 71: Fourth dielectric line
51, 74: Mixer
52, 72, 75: Non-reflective termination
67: Transmitting antenna
69: Receive antenna
73: Fifth dielectric line
205, 206: Ferrite plate
207, 208: first microstrip line (first transmission line)
209, 210: second microstrip line (second transmission line)
211, 212: Third microstrip line (third transmission line)
207a: Input terminal
212a: Output terminal
213, 214: Grounding conductor
215, 216: Terminating resistor
231: High frequency oscillator
232: Turnout
232a: Input terminal
232b: One output terminal
232c: The other output terminal
233: Modulator
234: Circulator
234a: Input terminal
234b: One output terminal
234c: The other output terminal
235: Transmitting and receiving antenna
236: Mixer
237: Switch
238: Isolator
239: Transmitting antenna
240: receiving antenna A: first circulator B: second circulator C, D: circulator (for millimeter wave radar module)
C1, C2: circulator _{W 1, W 2, W 3} : the millimeter-wave signal O: millimeter wave oscillator R1, R2: the millimeter-wave radar module

Claims (13)

The first, second, and third transmission lines that transmit the high-frequency signal are connected to the peripheral portion of the magnetic material radially by the first, second, and third connecting portions, respectively, and input from one of the connecting portions. A circulator that outputs the high-frequency signal from one of the other adjacent connecting parts, and a non-reflective terminator connected to the other end of the third transmission line having one end connected to the third connecting part. In the isolator, the length of the third transmission line is reflected by the non-reflection terminator through the third transmission line and returned to the first transmission line as a part of the high-frequency signal Wa. And the other part of the high-frequency signal leaking from the second transmission line to the first transmission line via the circulator is Wb, and the phase difference at the center frequency between these Wa and Wb is δ. Δ = (2N + 1) An isolator that is set to be π (where N is an integer). The first, second, and third transmission lines that transmit the high-frequency signal are connected to the peripheral portion of the magnetic material radially by the first, second, and third connecting portions, respectively, and input from one of the connecting portions. The first and second circulators that output the high-frequency signal from one of the other adjacent connecting portions are configured such that the second transmission line of the first circulator is the first transmission line of the second circulator. In an isolator in which a non-reflection terminator is connected to the other end of the third transmission line, one end of which is connected to each of the third connection portions. A high-frequency signal transmitted from the first transmission line of the first circulator to the second transmission line; a high-frequency signal transmitted from the second transmission line to the first transmission line; Frequency dependence of isolation characteristics, transmission of the high-frequency signal transmitted from the first transmission line to the second transmission line of the second circulator, and transmission from the second transmission line to the first transmission line The isolator is characterized in that the frequency dependence of the isolation characteristic from the high-frequency signal to be generated is different. Each of the first and second circulators reflects the length of the third transmission line through the third transmission line, is reflected by the non-reflection terminator, and leaks to the first transmission line. The part of the high-frequency signal thus generated is referred to as Wa, and the other part of the high-frequency signal leaked from the second transmission line via the circulator to the first transmission line is referred to as Wb. 3. The isolator according to claim 2, wherein δ is set to be δ = (2N + 1) · π (where N is an integer), where δ is the phase difference at. Between two parallel plate conductors arranged at intervals of one-half or less of the wavelength of the high-frequency signal, opposed to each other on the inner surface of the parallel plate conductor, and the two ferrite plates The input dielectric line for inputting a high-frequency signal, the termination dielectric line provided with a non-reflective termination at the tip, and the high-frequency signal input to the input dielectric line are output. A first circulator and a second circulator each having an output dielectric line to be connected to each other, wherein the first and second circulators are connected to the output dielectric line of the first circulator. The high frequency signal of the input dielectric line of the first circulator is input while being connected by serving also as the input dielectric line of the second circulator. A voltage controlled oscillator is connected to the power end, and the high frequency signal transmitted from the input dielectric line to the output dielectric line of the first circulator and the input dielectric line from the output dielectric line The frequency dependence of the isolation characteristic from the high-frequency signal transmitted to the line, and the high-frequency signal transmitted from the input dielectric line of the second circulator to the output dielectric line and the output dielectric line. A high-frequency oscillator characterized in that the frequency dependence of isolation characteristics differs from a high-frequency signal transmitted to the input dielectric line. 5. The frequency dependency is adjusted by making at least one of an interval and a dimension of the two ferrite plates of the first circulator and the second circulator different from each other. High frequency oscillator. A high-frequency oscillator comprising: the isolator according to any one of claims 1 to 3; and a voltage-controlled oscillator that is connected to an input terminal of the isolator and generates a high-frequency signal. Between parallel plate conductors arranged at intervals of 1/2 or less of the wavelength of the millimeter wave signal,
A millimeter wave signal oscillating unit attached to the first dielectric line and outputting a millimeter wave signal output from the high frequency oscillator to the first dielectric line;
A pulse modulator interposed in the middle of the first dielectric line to pulse the millimeter wave signal and output it from the first dielectric line as a millimeter wave signal for transmission;
Proximity is arranged so that one end side is electromagnetically coupled to the first dielectric line, or one end is joined to the first dielectric line, and a part of the millimeter wave signal for transmission is propagated to the mixer side A second dielectric line,
A first connecting portion, a second connecting portion, and a third connecting portion arranged at predetermined intervals on a peripheral portion of a ferrite plate arranged in parallel to the parallel plate conductor and serving as input / output ends of the millimeter wave signal, respectively. A circulator for outputting the millimeter wave signal input from one of the connection portions from the other connection portion adjacent in the clockwise or counterclockwise direction in the plane of the ferrite plate, A circulator to which the first connection portion is connected to an output end of the millimeter wave signal of the first dielectric line;
A third dielectric line connected to the second connection portion of the circulator, for propagating the millimeter wave signal for transmission, and having a transmission / reception antenna at a tip portion;
A fourth wave connected to the third connection part of the circulator, received by the transmission / reception antenna, propagates through the third dielectric line, and propagates the received wave output from the third connection part to the mixer. A dielectric line;
The middle part of the second dielectric line and the middle part of the fourth dielectric line are close to each other or joined so as to be electromagnetically coupled, and a part of the millimeter wave signal for transmission and the received wave A mixer that generates an intermediate frequency signal by mixing
A non-reflective terminator connected to the end of the second dielectric line opposite to the mixer;
6. The high frequency transmitter / receiver according to claim 4, wherein the high frequency oscillator of the millimeter wave signal oscillating unit is the high frequency oscillator according to claim 4 or 5. Between parallel plate conductors arranged at intervals of 1/2 or less of the wavelength of the millimeter wave signal,
A millimeter wave signal oscillating unit attached to the first dielectric line and outputting a millimeter wave signal output from the high frequency oscillator to the first dielectric line;
A pulse modulator interposed in the middle of the first dielectric line to pulse the millimeter wave signal and output it from the first dielectric line as a millimeter wave signal for transmission;
Proximity is arranged so that one end side is electromagnetically coupled to the first dielectric line, or one end is joined to the first dielectric line, and a part of the millimeter wave signal for transmission is propagated to the mixer side A second dielectric line,
A first connecting portion, a second connecting portion, and a third connecting portion arranged at predetermined intervals on a peripheral portion of a ferrite plate arranged in parallel to the parallel plate conductor and serving as input / output ends of the millimeter wave signal, respectively. A circulator for outputting the millimeter wave signal input from one of the connection portions from the other connection portion adjacent in the clockwise or counterclockwise direction in the plane of the ferrite plate, A circulator to which the first connection portion is connected to an output end of the millimeter wave signal of the first dielectric line;
A third dielectric line connected to the second connection portion of the circulator, for propagating the millimeter wave signal for transmission, and having a transmission antenna at a tip portion;
A fourth dielectric line provided with a receiving antenna at the front end and a mixer at the other end;
A fifth dielectric that is connected to the third connection portion of the circulator, propagates a millimeter-wave signal received and mixed by the transmitting antenna, and attenuates the millimeter-wave signal by a non-reflective terminator provided at a tip portion. Tracks,
The middle part of the second dielectric line and the middle part of the fourth dielectric line are close to each other or joined so as to be electromagnetically coupled, and a part of the millimeter wave signal for transmission and the received wave A mixer that generates an intermediate frequency signal by mixing
A non-reflective termination connected to the opposite end of the mixer of the second dielectric line;
6. The high frequency transmitter / receiver according to claim 4, wherein the high frequency oscillator of the millimeter wave signal oscillating unit is the high frequency oscillator according to claim 4 or 5. The high-frequency oscillator according to claim 6, a branching device connected to an output end of the high-frequency oscillator and branching the high-frequency signal and outputting it to one output end and the other output end, and the one output end A modulator that modulates a high-frequency signal branched to one of the output ends and outputs a high-frequency signal for transmission, and a first terminal, a second terminal, and a third terminal around the magnetic body A circulator in which the output of the modulator is input to the first terminal, the high-frequency signal input from one of the terminals in this order being output from the next adjacent terminal, and the first of the circulator A transmission / reception antenna connected to the second terminal, the high-frequency signal branched to the other output end, connected between the other output end of the branching device and the third terminal of the circulator; Transmit / receive antenna RF transceiver, characterized by comprising a mixer for outputting the intermediate frequency signal by mixing the received high-frequency signal. The high-frequency oscillator according to claim 6, a branching device connected to an output end of the high-frequency oscillator and branching the high-frequency signal and outputting it to one output end and the other output end, and the one output end A modulator that modulates the high-frequency signal branched to one of the output ends and outputs a high-frequency signal for transmission, and one end connected to the output end of the modulator, the other end from the one end side An isolator that transmits the high-frequency signal for transmission to the side, a transmission antenna connected to the isolator, a reception antenna connected to the other output end side of the branching device, and the other output end of the branching device And a mixer connected between the receiving antenna and the high-frequency signal branched to the other output end and a high-frequency signal received by the transmitting / receiving antenna to output an intermediate-frequency signal. RF transceiver and said. A high-frequency transmitter / receiver according to any one of claims 7 to 10, and a distance information detector for processing the intermediate frequency signal output from the high-frequency transmitter / receiver to detect distance information to a detection target. A radar apparatus comprising: A radar device-equipped vehicle comprising the radar device according to claim 11, wherein the radar device is used for detection of an object to be detected. A small ship equipped with a radar apparatus, comprising the radar apparatus according to claim 11, wherein the radar apparatus is used for detection of an object to be detected.

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