JP2005160009A - Transmitting / receiving antenna and millimeter wave transmitter / receiver using the same - Google Patents

Abstract

In a millimeter wave radar using a millimeter wave transmitter / receiver, transient output fluctuation of a pulse modulator is suppressed from being directly transmitted to mixer output fluctuation due to internal reflection or the like.
In a millimeter wave transmitter / receiver using an NRD guide as a basic configuration and provided with a millimeter wave signal oscillating unit 21, a pulse modulator 22, a circulator 23, an antenna 24, and a mixer 25, a line of a third dielectric line is provided. A part of the millimeter wave signal transmitted through the third dielectric line through the third dielectric line and reflected back to the third connection portion of the circulator 23, and the circulator 23 Where δ = (2N−1) · π (where N is a phase difference at the center frequency with other millimeter wave signals leaked from the first connection portion to the third connection portion. Is a millimeter wave transceiver set to be Changes in the mixer output can be reduced, and millimeter wave transmission / reception performance can be improved.
[Selection] Figure 5

Description

  The present invention relates to a millimeter-wave transceiver using a nonradiative dielectric line (NRD guide) used in a millimeter-wave radar module, a millimeter-wave wireless communication device, etc., and a pulse-modulated millimeter-wave signal for transmission In a millimeter wave transmitter / receiver having a switching control unit capable of blocking the output to the reception system due to internal reflection or the like, from the mixer caused by the transient characteristics of the pulse modulator when the switching control unit is closed (ON) This relates to suppression of fluctuations in the output signal. Also, it is a transmission / reception antenna in which an antenna (including a primary radiator) is connected to one of the input / output transmission lines of the circulator, and a part of the millimeter wave signal of the transmission system leaks directly to the reception system. The present invention relates to a transmission / reception antenna and a millimeter wave transceiver using the same.

  Conventionally, for example, a pulse modulation method disclosed in Patent Document 1 has been proposed as a method of a millimeter wave transceiver that is expected to be applied to a millimeter wave radar module, a millimeter wave wireless communication device, or the like.

  However, in the pulse modulation method, a part of the pulse-modulated millimeter-wave signal for transmission is output as an unnecessary signal to the reception system due to reflection inside the transmitter / receiver, which adversely affects the reception performance. was there.

  The inventor has already proposed a solution to this problem (see Japanese Patent Application No. 2001-392767). An example of the configuration is shown in a block circuit diagram in FIG. 11 and a plan view in FIG. The basic configuration of the NRD guide used in the examples of these configurations is as shown in a partially broken perspective view in FIG. 4, and a dielectric between the parallel plate conductors 1 and 2 arranged in parallel at a distance a. The body track 3 is sandwiched.

  The millimeter wave transmitter / receiver of the example shown in FIG. 6 is an example in which a transmission antenna and a reception antenna are integrated, and between the parallel plate conductors 51 arranged at intervals of 1/2 or less of the wavelength of the millimeter wave signal. In addition, a millimeter wave signal oscillating unit 52 attached to the first dielectric line 53 and frequency-modulating a high frequency signal output from the high frequency diode and propagating the first dielectric line 53 as a millimeter wave signal, A pulse modulator (not shown) interposed in the middle of the dielectric line 53 and pulsed from the first dielectric line 53 as a millimeter wave signal for transmission and output from the first dielectric line 53, and a first dielectric A second dielectric line 58 is disposed close to the line 53 so that one end thereof is electromagnetically coupled, or one end is joined to the first dielectric line 53 to propagate a part of the millimeter wave signal to the mixer 59 side. And ferrite arranged parallel to the parallel plate conductor 51 A first connection portion 54a, a second connection portion 54b, and a third connection portion 54c, which are arranged at predetermined intervals on the peripheral edge of the plate and are respectively input / output ends of millimeter wave signals; A circulator 54 for outputting a millimeter wave signal input from a connection portion from another connection portion adjacent in the clockwise or counterclockwise direction within the plane of the ferrite plate, and the millimeter wave signal of the first dielectric line 53 A circulator 54 having a first connecting portion 54a connected to the output end, and a third dielectric line connected to the second connecting portion 54b of the circulator 54 to propagate a millimeter-wave signal and have an antenna 56 at the tip portion 55 and the third connection portion 54c of the circulator 54, received by the antenna 56, propagated through the third dielectric line 55, and output from the third connection portion 54c through the second connection portion 54b. Fourth dielectric wire that propagates received wave to mixer 59 57 and the middle of the second dielectric line 58 and the middle of the fourth dielectric line 57 are brought close to each other or joined so as to be electromagnetically coupled, and the millimeter propagated through the second dielectric line 58. This is a millimeter wave transmitter / receiver provided with a mixer 59 for mixing a part of the wave signal and a received wave propagating through the fourth dielectric line 57 to generate an intermediate frequency signal. In this example, a switching control unit (not shown) that opens the output terminal when the pulse-modulated millimeter-wave signal for transmission is output from the pulse modulator is provided at the output terminal of the mixer 59. This prevents unnecessary signals from being output to the receiving system after the mixer 59 almost simultaneously with the input of the pulsed signal for starting the pulsed operation of the pulse modulator to the pulse modulator. Can do.

  FIG. 11 is a block circuit diagram showing the configuration of each part when the millimeter wave transceiver shown in FIG. 6 is used as a millimeter wave radar.

  In FIG. 11, reference numeral 11 denotes a VCO having a Gunn diode and a varactor diode, and operates by inputting a signal to the IN-2 terminal for inputting a modulation signal. The output signal of the VCO 11 is subjected to pulse modulation by the pulse modulator 12 by inputting the pulsed signal input to the IN-1 terminal to the pulse modulator 12. In FIG. 6, the pulse modulator 12 is interposed in the middle of the first dielectric line 53, and is a switch configured as shown in a perspective view in FIG.

  In the configuration of the pulse modulator shown in FIG. 8, a choke-type bias supply line 90 is formed on one main surface of a substrate 88, and a solder-mounted beam is connected between connection electrodes 81 and 81 formed in the middle thereof. This is a switch provided with a lead type PIN diode or a Schottky barrier diode 80. Such a switch is installed between the end face of the first first dielectric line 53 so that the PIN applied voltage or the Schottky barrier diode 80 is in the horizontal direction, and pulse modulation is performed. Used as vessel 12

  13 is a circulator that transmits a millimeter wave signal to the antenna 14 side during transmission and a reception wave is transmitted to the mixer 15 side during reception, 14 is an antenna for transmitting and receiving millimeter wave signals, and the antenna 14 is a circulator 13 For example, a horn antenna or the like connected to a metal waveguide or a dielectric waveguide filled with a dielectric to the metal waveguide. Reference numeral 15 denotes a mixer that outputs an intermediate frequency signal for detecting the distance to the target by mixing the millimeter wave signal output from the VCO 11 and the received signal received by the antenna 14.

  Reference numeral 16 denotes a switch as a switch for blocking or passing the intermediate frequency signal output from the mixer 15. Reference numeral 19 denotes a control unit that controls the opening / closing (on-off) timing of the switch 16. The switch 16 and the control unit 19 constitute a switching control unit.

  The control unit 19 receives a pulsed signal of the IN-1 terminal so as to be interlocked with the pulse modulator 12, and the millimeter wave signal for transmission modulated by the pulse modulator 12 is converted into an NRD guide and a dielectric conductor. The switching timing is such that it is blocked by the switch 16 before being reflected at the connection with the wave tube or leaking from the circulator 13 and being output as an unnecessary signal through the mixer 15 and being input to the amplifier 18. To control.

  Reference numeral 17 denotes a capacitor for AC coupling the switch 16 and the amplifier 18.

  With the above configuration, the pulse-modulated millimeter-wave signal for transmission can be blocked so that it does not leak into the mixer 15 and leak to the receiving system at the subsequent stage, so that the detection accuracy of the millimeter-wave radar system can be improved.

  In addition, as a transmission / reception antenna used by being incorporated in such a millimeter-wave transceiver, an antenna having a radiator connected to one of input / output transmission lines of a circulator is known. An example of a transmission / reception antenna is disclosed in Patent Document 1 and also in Patent Document 2.

  The conventional transmission / reception antenna disclosed in Patent Document 1 or Patent Document 2, for example, as shown in a plan view in FIG. 12, includes first, second and third transmission lines 14 and 15 for transmitting a millimeter wave signal. , 16 are connected radially to the periphery of the magnetic body 17, and one end is connected to one connection part of a circulator that outputs a millimeter wave signal input from one connection part from one of the other adjacent connection parts. The antenna 18 is connected to the other end of the third transmission line 16.

In such a conventional transmission / reception antenna, the millimeter wave signal output from the transmission system is input to the first transmission line 14 and output from the first transmission line 14 to the third transmission line 16. The millimeter wave signal input to the transmission line 16 is transmitted from the antenna 18 connected to the third transmission line 16, while the millimeter wave signal received by the same antenna 18 is input to the third transmission line 16, Output from the third transmission line 16 to the second transmission line 15 and output from the second transmission line 15 to the receiving system, and transmit and receive millimeter-wave signals using one antenna 18 in common. It can be done.
JP 2000-258525 A JP 7-77576 A

  However, even in the configuration proposed in Japanese Patent Application No. 2001-392767, the present inventors have made extensive studies to further improve the performance of the millimeter-wave transceiver, and as a result, the following improvements are desired. I found it.

  As a problem in which such further improvement is desired, there is a point that the fluctuation of the output level of the millimeter wave signal for transmission from the pulse modulator 12 due to the transient response characteristic of the pulse modulator 12 should be considered. .

  In general, the pulse modulator 12 using a high-frequency diode has characteristics inherent to the high-frequency diode such as a zero bias capacity. Therefore, in many cases, even if an ideal pulse signal is input for driving, it is used for modulation. As a result, the millimeter-wave signal output from the pulse modulator 12 is distorted from the original waveform, resulting in level fluctuations that deviate from the design intention. There is a problem of becoming.

  The millimeter wave transmitter / receiver proposed in Japanese Patent Application No. 2001-392767 can block the transmission millimeter wave signal output from the pulse modulator 12 from being directly mixed into the mixer 15 by reflection or the like and output to the receiving system. However, the level fluctuation as described above needs to shut off unnecessary signals generated in the receiving system, in this case, the mixer 15, so that the level fluctuation as described above is settled and steady. Until the state is stabilized, the switch 16 cannot be closed (ON), and there is a problem that transmission and reception may not be performed for a certain time immediately after the pulse signal is transmitted.

  Therefore, it is a problem that improvement is desired to suppress the level fluctuation of the output of the mixer 15 due to the transient fluctuation of the output level of the millimeter wave signal from the pulse modulator 12.

  As one of the countermeasures to solve this problem, for example, the pulse modulator 12 is combined in multiple stages to improve the ON / OFF ratio characteristics of the pulse modulator 12, and the pulse modulator 12 which is particularly problematic is turned off. Although the method of suppressing the level fluctuation at the time is effective, for this purpose, the configuration becomes complicated. Therefore, the assembly man-hour of the millimeter wave transceiver is increased, the millimeter wave transceiver itself and the millimeter There is a problem that the wave radar device is increased in size.

  In the conventional transmission / reception antenna as disclosed in Patent Document 1 or Patent Document 2, a part of the millimeter wave signal input from the transmission system is transferred from the first dielectric line 14 to the second dielectric line. Since this leaks to 15 and interferes with the millimeter wave signal to be received, there is a problem that the reception characteristics of the receiving system are deteriorated.

  The present invention has been devised to solve the above-described problems that are desired to be improved. The purpose of the present invention is to output a pulse-modulated millimeter wave signal for transmission to a receiving system by internal reflection or the like. An object of the present invention is to provide a millimeter wave transmitter / receiver having a switch capable of interrupting transmission and reception so that transmission / reception can be performed immediately after a pulse signal is transmitted.

  Another object of the present invention is to provide a transmission / reception antenna capable of suppressing a part of a millimeter-wave signal in a transmission system from directly leaking to a reception system, and a millimeter-wave transmission / reception having high millimeter-wave transmission / reception performance using the transmission / reception antenna. Is to provide a vessel.

  In the first transmission / reception antenna of the present invention, the first, second, and third transmission lines for transmitting a millimeter wave signal are connected to the peripheral portion of the magnetic material radially by the first, second, and third connection portions, respectively. The circulator for outputting the millimeter wave signal input from one of the connection portions from one of the other connection portions adjacent thereto, and the third transmission line having one end connected to the third connection portion. A transmission / reception antenna having an antenna connected to the other end, the line length of the third transmission line being reflected by the antenna through the third transmission line and returning to the second connection part The leaked part of the millimeter wave signal is referred to as Wa, and the other part of the millimeter wave signal leaked from the first connection part to the second connection part via the circulator is referred to as Wb. If the phase difference at the center frequency of A, δ = (2N-1) · π (although, N represents an integer.) Is characterized in that set to be.

  Further, the second transmitting / receiving antenna of the present invention includes two ferrites between the flat conductors arranged in parallel at intervals of 1/2 or less of the wavelength of the millimeter wave signal so as to face each other on the inner surface of the flat conductor. The first, second and third dielectric lines are arranged at the peripheral edges of the two ferrite plates and input and output the millimeter wave signal radially, respectively. The third dielectric having one end connected to the third connection part to a circulator connected to the circulator for outputting the millimeter wave signal input from one connection part from one of the other adjacent connection parts. A through-hole is provided in one of the plate conductors at a portion facing a portion where the electric field of the LSM mode standing wave of the body line is strong, and an antenna or a waveguide or a primary radiator connected to the antenna is connected to the through-hole. With a transmitting / receiving antenna connected Then, the length from the one end of the third dielectric line to the part facing the through hole is reflected by the through hole through the third dielectric line and returned to the second dielectric line. A part of the millimeter wave signal leaked to the connection part is referred to as Wa, and another part of the millimeter wave signal leaked from the first connection part to the second connection part via the circulator is assumed to be Wb. It is characterized in that δ = (2N−1) · π (where N is an integer), where δ is the phase difference at the center frequency between Wb and Wb.

The first millimeter-wave transceiver of the present invention uses the first transmitting / receiving antenna of the present invention,
Between flat conductors arranged in parallel at intervals of half or less of the wavelength of the millimeter wave signal,
A millimeter-wave signal oscillating unit that is attached to the first dielectric line, modulates a high-frequency signal output from the high-frequency diode, and propagates the first dielectric line as a millimeter-wave signal;
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;
Second end is disposed close to the first dielectric line so that one end side is electromagnetically coupled, or one end is joined to the first dielectric line to propagate a part of the millimeter wave signal to the mixer side. A dielectric line of
A first connecting portion and a second connecting portion are arranged radially at the peripheral portions of the two ferrite plates disposed opposite to each other on the inner surface of the flat conductor, and serve as input / output ends of the millimeter wave signal, respectively. A circulator that has a connection portion and a third connection portion, and outputs the millimeter wave signal input from one of the connection portions from one of the other adjacent connection portions; A circulator in which the first connection portion is connected to an output end of the millimeter wave signal on a line;
A third dielectric line connected to the second connection part of the circulator, for propagating the millimeter wave signal and having an antenna at a tip part;
A fourth dielectric connected to the third connecting portion of the circulator, received by the antenna and propagating through the third dielectric line, and propagating the received wave output from the third connecting portion to the mixer; Body track,
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 and the received wave are mixed. And a mixer for generating an intermediate frequency signal,
The line length of the third dielectric line is reflected from the tip part of the millimeter wave signal for transmission through the third dielectric line and returned to the third connection part. The millimeter wave signal of the part is denoted by Wa, and another part of the millimeter wave signal leaking from the first connection part to the third connection part via the circulator is denoted by Wb, and the center frequency of these Wa and Wb When the phase difference at δ is δ, δ = (2N−1) · π (where N is an integer) is set.

Moreover, the 2nd millimeter wave transmitter / receiver of this invention uses the 2nd transmit / receive antenna of this invention,
Between flat conductors arranged in parallel at intervals of half or less of the wavelength of the millimeter wave signal,
The second transmitting and receiving antenna of the present invention;
A millimeter-wave signal oscillating unit that is attached to the first dielectric line, modulates a high-frequency signal output from a high-frequency diode, and propagates the first dielectric line as a millimeter-wave signal;
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;
A fourth end is disposed close to the first dielectric line so that one end is electromagnetically coupled, or one end is joined to the first dielectric line to propagate a part of the millimeter wave signal to the mixer side. A dielectric line of
The middle part of the fourth dielectric line and the middle part of the third dielectric line are close to each other or joined so as to be electromagnetically coupled, and a part of the millimeter wave signal and reception received by the transmitting / receiving antenna And a mixer that generates an intermediate frequency signal by mixing the wave.

  Further, in the first or second millimeter wave transceiver according to the present invention, in the above configuration, a power ratio of the part of the millimeter wave signal Wa to the other part of the millimeter wave signal Wb is 0.27 or more. In addition, the phase difference δ is set to δ = (2N−1) · π ± 0.42π (where N is an integer).

  In the first or second millimeter-wave transmitter / receiver of the present invention, in the above configurations, the pulse-modulated millimeter-wave signal for transmission is output from the pulse modulator to the output end of the mixer. In some cases, a switching control unit for opening the output terminal is provided.

  According to the first transmission / reception antenna of the present invention, the first, second and third transmission lines for transmitting the millimeter-wave signal are first, second and third connection portions radially at the peripheral portion of the magnetic body, respectively. The third transmission having one end connected to the third connection section to a circulator connected to the circulator for outputting the millimeter wave signal input from one of the connection sections from one of the other adjacent connection sections. A transmission / reception antenna having an antenna connected to the other end of the line, wherein the length of the third transmission line is reflected by the antenna through the third transmission line and returned to the second connection line. A part of the millimeter wave signal leaked to the part is referred to as Wa, and another part of the millimeter wave signal leaked from the first connection part to the second connection part via the circulator is assumed to be Wb. Let δ be the phase difference at the center frequency with Wb. Δ = (2N−1) · π (where N is an integer), the phase difference δ between Wa and Wb is δ = (2N−1) · π. Therefore, the two millimeter-wave signals Wa and Wb leaked to the second transmission line can be surely brought into exactly opposite phases with each other, and can effectively cancel each other out. A millimeter-wave signal leaking from the first transmission line to the second transmission line on the reception system side can be suppressed, and the transmission / reception antenna can improve the reception characteristics of the reception system.

  Further, according to the second transmitting / receiving antenna of the present invention, two flat antennas are arranged opposite to each other between the flat conductors arranged in parallel at intervals of 1/2 or less of the wavelength of the millimeter wave signal. The first, second, and third dielectric lines that input and output the millimeter wave signal radially to the periphery of the two ferrite plates are respectively first, second, and third. A circulator connected at a connecting portion and outputting the millimeter wave signal input from one connecting portion from one of the other connecting portions adjacent to the third connecting portion, one end connected to the third connecting portion. A through-hole is provided in one of the plate conductors at a portion of the dielectric line facing the portion where the electric field of the standing wave of the LSM mode is strong, and an antenna or a waveguide or primary radiation connected to the through-hole. Transmitting / receiving A length from the one end of the third dielectric line to a portion facing the through hole is reflected by the through hole through the third dielectric line and returned to the first dielectric line. Wa is a part of the millimeter wave signal leaked to the connection part 2 and Wb is another part of the millimeter wave signal leaked from the first connection part to the second connection part via the circulator. Since δ = (2N−1) · π (where N is an integer) when the phase difference at the center frequency between Wa and Wb is δ, Wa and Wb Phase difference δ of δ = (2N−1) · π, the two millimeter-wave signals Wa and Wb leaking to the second dielectric line are surely made to have exactly opposite phases, and each other is effectively Since it can be made to cancel each other, the first dielectric wire on the transmission system side Millimeter wave signal leaking to the second dielectric line is the reception system side can be suppressed from the transmitting and receiving antenna which is capable of improving the reception characteristic of the receiving system.

  According to the first millimeter-wave transceiver of the present invention, with the above-described configuration, the third millimeter-wave signal for transmission passes through the third dielectric line, is reflected at the tip, and returns to the third connection portion. The leaked part of the millimeter wave signal is referred to as Wa, and the other part of the millimeter wave signal leaked from the first connection part to the third connection part via the circulator is referred to as Wb. And δ = (2N−1) · π where the phase difference of the third dielectric line is δ = (2N−1) · π (However, N is an integer.) Therefore, some of the millimeter wave signals Wa interfere with the other part of the millimeter wave signals Wb so as to weaken each other at the third connection portion. , The intensity of the millimeter wave signal obtained by interference of some of the millimeter wave signals Wa and other part of the millimeter wave signals Wb -) Is suppressed to be smaller than the intensity (power) of the other part of the millimeter wave signal Wb before the interference, the reflection from the pulse modulator to the inside of the millimeter wave transceiver It is possible to reduce the change in the mixer output when the millimeter wave signal leaks from the third connection part of the circulator due to lack of circulator isolation, etc. and directly enters the mixer, and this makes it possible to select the desired mixer output. Since only objects can be easily detected, millimeter wave transmission / reception performance can be improved.

  Further, according to the second millimeter-wave transceiver of the present invention, with the above-described configuration, it is possible to suppress part of the millimeter-wave signal in the transmission system from leaking to the reception system, and the millimeter-wave signal to be received Therefore, the reception characteristics of the reception system of the millimeter wave transceiver can be improved. This also increases the power of the millimeter wave signal in the transmission system, thereby extending the transmission distance of the millimeter wave signal transmitted by the transmission / reception antenna, and improving the S / N (signal-to-noise) ratio. Overall, millimeter wave transmission / reception performance can be improved.

  According to the first or second millimeter-wave transceiver of the present invention, the power ratio of some of the millimeter-wave signals Wa to the other part of the millimeter-wave signals Wb is 0.27 or more, and the phase difference When δ is δ = (2N−1) · π ± 0.42π (where N is an integer), some of the millimeter wave signals Wa and some of the other millimeter wave signals Wb are weakened. And the intensity of the millimeter wave signal combined by interference of some of the millimeter wave signals Wa and some of the other millimeter wave signals Wb. Since it can be realized with a phase difference δ within a range that is practically easy to set, it is possible to suppress to less than half of the total output intensity before interference with the wave signal Wb. Circulation due to reflections inside the transceiver and insufficient isolation of the circulator. The change in mixer output when a millimeter wave signal for transmission leaks directly from the third connection of the mixer and enters the mixer can be easily and reliably reduced, so that only the desired mixer output can be obtained. Can be detected most favorably, so that the millimeter-wave transmission / reception performance can be further improved.

  According to the first or second millimeter-wave transceiver of the present invention, the output terminal is opened at the output terminal of the mixer when the pulse-modulated millimeter-wave signal for transmission is output from the pulse modulator. When the switching control unit is set to the OFF state, the millimeter wave output of the pulse modulator is provided even if the switching control unit is closed (ON) immediately after the transmission millimeter wave signal is output from the pulse modulator. Since the fluctuation of the mixer output due to the transient fluctuation is sufficiently reduced, millimeter wave transmission / reception can be started immediately after sending the pulse signal without being disturbed by unnecessary signals.

  As described above, according to the transmission / reception antenna of the present invention and the millimeter wave transmitter / receiver of the present invention using the antenna, a pulse-modulated millimeter wave signal for transmission is transmitted to the reception system by internal reflection or the like by the above-described configurations. In a millimeter-wave transceiver having a switching control unit that can block output, since the cutoff time by the switching control unit can be shortened to about the time when a pulse-modulated transmission millimeter-wave signal is being sent, The time domain in which millimeter wave transmission / reception can be performed will be high performance. This makes it possible to improve the detection performance at a short distance when applied to a millimeter wave radar. In addition, since a part of the millimeter wave signal in the transmission system can be prevented from leaking directly to the reception system, the millimeter wave transmission / reception performance can be improved.

  The transmission / reception antenna of the present invention and the millimeter wave transmitter / receiver of the present invention using the same will be described in detail below, taking the case of using them for millimeter wave radar as an example.

  1A and 1B are schematic views showing an example of an embodiment of a first transmitting / receiving antenna according to the present invention, in which FIG. 1A is a plan view and FIG. 2A and 2B are schematic views showing an example of an embodiment of the second transmitting / receiving antenna of the present invention, where FIG. 2A is a plan view and FIG. 2B is a B-B ′ sectional view thereof. FIG. 3 is a diagram showing the dependence of the isolation characteristics of the transmission / reception antenna shown in FIG. 1 or 2 on the phase difference δ. FIG. 4 is a schematic partially broken perspective view showing a basic configuration of a non-radiative dielectric line. FIG. 5 is a block circuit diagram showing the configuration of the millimeter wave signal transmission unit and the intermediate frequency signal transmission unit in an example of an embodiment in which the millimeter wave transceiver of the present invention is applied to a millimeter wave radar. . FIG. 6 is a plan view of a millimeter wave transceiver having a transceiver antenna. FIG. 7 is a plan view schematically showing an example of the embodiment of the second millimeter wave transceiver according to the present invention. FIG. 8 is a perspective view showing the configuration of the pulse modulator of the millimeter wave transceiver. FIG. 9 is a partially enlarged plan view of the vicinity of the third dielectric line in FIG. 6 in the millimeter wave transceiver according to the present invention. Also, FIG. 10 shows a part of the millimeter wave signal Wa that passes through the third dielectric line, reflects off the connecting portion with the antenna that is the tip portion thereof, and leaks back to the third connecting portion. Shows a change in the output intensity of the millimeter wave signal due to the phase difference δ when the other millimeter wave signal Wb leaking from the connection part to the third connection part through the circulator interferes and combines. It is a graph.

  1 to 4, reference numerals 1 and 2 are flat conductors, and 3, 4 and 5 are dielectric lines as transmission lines, which are first, second and third dielectric lines, respectively. Further, 6 and 7 are ferrite plates as magnetic bodies, 8 is an antenna, and 9 is a through hole provided in the flat conductor 2. Further, 3a, 4a and 5a are one ends of the first, second and third dielectric lines 3, 4 and 5, respectively, and 5b is the other end of the third dielectric line. Reference numerals 3c, 4c and 5c denote first, second and third connecting portions, respectively. Wa and Wb are reflected from the antenna 8 or the through-hole 9 and returned from the millimeter wave signal leaking from the third dielectric line 5 to the second dielectric line 4 and the first dielectric line 3, respectively. A millimeter wave signal leaking into the second dielectric line 4 is shown. Note that the flat conductors 1 and 2 are not shown in FIGS. In FIG. 2, the antenna attached to the through hole 9 or the waveguide or primary radiator to which the antenna is connected is not shown.

  In FIG. 5, 21 is a millimeter wave signal oscillating unit, 22 is a pulse modulator (RF switch), 23 is a circulator, 24 is an antenna, 25 is a mixer, 26 is a switch (IF switch), 28 is an amplifier, 29 Is a timing generator, and 30 is a coupler (directional coupler).

  6 and 7, 51 is a flat conductor (the lower flat conductor of the parallel flat conductors), 52 is a millimeter wave signal oscillator, 53 is a first dielectric line, 54 is a circulator, The third dielectric line, 56 is an antenna, 57 is a fourth dielectric line, 58 is a second dielectric line, and 59 is a mixer. Reference numerals 57a and 58a denote non-reflection terminators. 6 and 7, the upper flat conductor is not shown.

  Note that the flat conductors 1 and 2, the first dielectric line 3, the second dielectric line 4, the third dielectric line 5 and the antenna 8 in FIG. This corresponds to the first dielectric line 53, the fourth dielectric line 57, the third dielectric line 55, and the antenna 56. In addition, the flat conductors 1 and 2, the first dielectric line 3, the second dielectric line 4, and the third dielectric line 5 in FIG. 2 are respectively the flat conductor 51 and the first dielectric line 5 in FIG. 7. This corresponds to the dielectric line 53, the second dielectric line 58, and the third dielectric line 55.

  The example of the first transmitting / receiving antenna of the present invention shown in FIG. Two ferrite plates 6, 7 are arranged opposite to each other on the inner surface, and first, second, and third dielectrics that radially input and output millimeter wave signals to the periphery of the two ferrite plates 6, 7. The body lines 3, 4 and 5 are connected by the first, second and third connection portions 3c, 4c and 5c, respectively, and the millimeter wave signal input to one connection portion is received from one of the other adjacent connection portions. A transmission / reception antenna in which an antenna 8 is connected to the other end 5b of the third dielectric line 5 whose one end 5a is connected to the third connection portion 5c, to the output circulator C, and the third dielectric The line length of the line 5 is reflected by the antenna 8 through the third dielectric line 5 and returned. Then, a part of the millimeter wave signal leaked to the second connection portion 4c is defined as Wa, and the other part of the millimeter wave signal leaked from the first connection portion 3c to the second connection portion 4c via the circulator C. In this configuration, Wb is set such that δ = (2N−1) · π (where N is an integer), where δ is the phase difference at the center frequency between Wa and Wb.

  In the example of the first transmitting / receiving antenna of the present invention shown in FIG. 1, the millimeter wave signal output from the transmission system is transmitted from the first dielectric line 3 via the circulator C, as in the conventional transmitting / receiving antenna. The millimeter wave signal transmitted from the antenna 8 through the third dielectric line 5 and received by the antenna 8 is output from the third dielectric line 5 through the second dielectric line 4 to the receiving system. To work.

  However, at that time, in the first transmission / reception antenna of the present invention, as described above, when the line length of the third dielectric line 5 is δ, the phase difference at the center frequency of Wa and Wb is Since δ = (2N−1) · π (where N is an integer), the millimeter wave signal Wa leaking from the first dielectric line 3 to the second dielectric line 4 is set. And the millimeter wave signal Wb which is reflected back from the antenna 8 and leaks from the third dielectric line 5 to the second dielectric line 4 is surely made in exactly the opposite phase and effectively attenuated. Since they can interfere with each other and cancel each other, it is possible to suppress the millimeter wave signal leaking from the first dielectric line 3 on the transmission system side to the second dielectric line 4 on the reception system side. It is possible to improve the reception characteristics of the reception system.

  Next, this will be described in detail with reference to the diagram shown in FIG. First, here, the millimeter leaking from the first dielectric line 3 to the second dielectric line 4 with respect to the intensity (unit: watt (W)) of the millimeter wave signal input to the first dielectric line 3. The ratio of the intensity (unit: watt (W)) of the wave signal Wa + Wb is defined as isolation, and the dependence of this isolation on the phase difference δ is defined as isolation characteristics. In this isolation characteristic, the smaller the isolation, the smaller the millimeter wave signal Wa + Wb leaking from the first dielectric line 3 on the transmission system side to the second dielectric line 4 on the reception system side. Show.

  FIG. 3 schematically shows this isolation characteristic as a diagram, where the horizontal axis and the vertical axis are the phase difference δ (unit: radians) and isolation (no unit), respectively, and the solid characteristic curve is The dependence of the oscillation characteristics on the phase difference δ is shown.

  The isolation characteristics of the transmission / reception antenna shown in FIG. 1 change according to A · cos δ (A is a proportional coefficient, which is a real number) as shown by a diagram in FIG. And the millimeter wave signal Wa leaking from the third dielectric line 5 to the second dielectric line 4 and the millimeter wave signal Wb leaking from the first dielectric line 3 to the second dielectric line 4 Is the smallest when the phase difference δ is ± π, ± 3π,..., (2N−1) · π (where N is an integer).

  Therefore, if the third dielectric line 5 has a line length satisfying δ = (2N−1) · π, the millimeter wave leaks from the first dielectric line 3 to the second dielectric line 4. The signal Wa + Wb can be minimized in such a configuration.

  By the way, in order to make the 3rd dielectric line 5 into such conditions, generally, the line length of the 3rd dielectric line 5 is set to (2N-1) / 4 * (lambda) g (n is an integer, A method of setting λg as a wavelength of the millimeter wave signal in the third dielectric line 5 is known. However, actually, the apparent reflection point of the millimeter wave signal at the antenna 8 is at a position different from the other end 5b of the third dielectric line, so the line length of the third dielectric line 5 Is set to (2N−1) / 4 · λg + L, which is the line length corrected from the length of (2N−1) / 4 · λg by the length L, the first dielectric line 3 to the second dielectric line 4 The millimeter wave signal Wa + Wb leaking to the bottom can be minimized in such a configuration. The reason why the apparent reflection point of the millimeter wave signal at the antenna 8 is different from the position of the other end 5 b of the third dielectric line 5 is that when the millimeter wave signal is reflected by the antenna 8, This is because the phase is advanced or delayed.

  In the transmission / reception antenna of the present invention and the millimeter wave transmitter / receiver of the present invention, the phase difference δ is not calculated as (2N−1) / 4 · λg + L after the length L is obtained. And the line length of the third dielectric line 5 is set so that the phase difference δ is δ = (2N−1) · π. Specifically, the line length of the third dielectric line 5 may be set as follows.

  First, the line length of the third dielectric line 5 is set to (2n−1) / 4 · λg, and the input end (the other end) of the first dielectric line 3 and the second dielectric line 4 are The test terminal of the network analyzer is connected to the output end (the other end), respectively, and the transmission characteristic from the first dielectric line 3 to the second dielectric line 4 is measured. Next, the line length of the third dielectric line 5 is changed from the initially set length, and some of the lengths differ from the first dielectric line 3 to the second dielectric line. The transmission characteristic to the body line 4 is measured by the same method. Then, the measured value of the transmission characteristic is plotted on a diagram as shown in FIG. 3 with the vertical axis as the transmission characteristic and the horizontal axis as the line length of the third dielectric line 5 and overlaps with 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) / of the third dielectric line 5 in which the phase difference δ is δ = (2N−1) · π 4 · λg + L should be read. In this way, the millimeter wave signal Wb leaking from the first dielectric line 3 to the second dielectric line 4 and reflected back from the antenna 8 and returned from the third dielectric line 5 to the second dielectric line. The millimeter wave signal Wa leaking into the body line 4 can be surely set to the opposite phase. As a result, the millimeter wave signal leaking from the first dielectric line 3 on the transmission system side to the second dielectric line 4 on the reception system side can be suppressed as compared with the conventional case.

  Next, an example of the second transmitting / receiving antenna of the present invention shown in FIG. 2 includes the flat conductor 1 between the flat conductors 1 and 2 arranged in parallel at intervals of 1/2 or less of the wavelength of the millimeter wave signal. The two ferrite plates 6 and 7 are arranged opposite to each other on the inner surfaces of the two ferrite plates 6 and 7, and first, second and second radial signals are input / output radially to the peripheral portions of the two ferrite plates 6 and 7. Three dielectric lines 3, 4 and 5 are connected by first, second and third connecting portions 3c, 4c and 5c, respectively, and other connecting portions adjacent to a millimeter wave signal inputted from one connecting portion. One flat conductor 1 at a portion facing the portion where the electric field of the standing wave of the LSM mode of the third dielectric line 5 whose one end is connected to the third connection portion 5c is strong. , 2 is provided with a through hole 9, and an antenna or an antenna is connected to the through hole 9. A transmission / reception antenna to which a waveguide or a primary radiator is connected, and the length from the one end 5a of the third dielectric line 5 to the portion facing the through hole 9 is set to the third dielectric line 5 A part of the millimeter wave signal reflected through the through-hole 9 and returned to the second connection portion 4c is defined as Wa, and the first connection portion 3c is passed through the circulator C to the second connection portion 4c. Δ = (2N−1) · π (where N is an integer), where Wb is the leaked part of the millimeter wave signal and δ is the phase difference at the center frequency between these Wa and Wb. ).

  Specifically, in order to set the length from the one end 5a of the third dielectric line 5 to the portion facing the through hole 9, the same method as the method for setting the line length of the third dielectric line 5 is used. What should I do? However, in the example shown in FIG. 2, it is necessary to provide the through-hole 9 in one of the flat conductors 1 and 2 at a portion facing the portion where the electric field of the LSM mode standing wave of the third dielectric line 5 is strong. There is.

  In this way, the millimeter wave signal Wb leaking from the first dielectric line 3 to the second dielectric line 4 and reflected by the through hole 9 and returned from the third dielectric line 5 to the second dielectric line 5. The millimeter-wave signal Wa leaking into the dielectric line 4 can be canceled out with exactly the opposite phase, and an antenna or the like (primary radiator or waveguide) in a direction perpendicular to the flat conductors 1 and 2. In the case of attaching an antenna or a primary radiator connected to a tube.), A millimeter wave signal can be efficiently transmitted from the third dielectric line 5 to the antenna or the like through the through hole 9.

  In the example of the second transmitting / receiving antenna of the present invention shown in FIG. 2, as described above, the length from the one end 5a of the third dielectric line 5 to the portion facing the through hole 9 is set as Wa and Wb. Since the phase difference at the center frequency is δ, δ = (2N−1) · π (where N is an integer), the second dielectric line 3 to the second The millimeter wave signal Wb leaking into the dielectric line 4 and the millimeter wave signal Wa reflected back through the through-hole 9 and leaking from the third dielectric line 5 to the second dielectric line 4 are surely obtained. Since the phase can be exactly reversed, they can be effectively weakened and interfered with each other, so that they can cancel each other, so that the first dielectric line 3 on the transmission system side is the second dielectric on the reception system side. The millimeter wave signal leaking to the line 4 can be suppressed, and the reception characteristics of the reception system can be improved. Can.

  Next, components of the transmission / reception antenna of the present invention will be described in detail. In the transmission / reception antenna of the present invention, the first, second and third transmission lines are non-radiative dielectrics in which dielectric lines 3, 4 and 5 are arranged between parallel plate conductors 1 and 2 as in the above example. A line (also referred to as an NRD guide) may be used.

  As shown in a partially broken perspective view in FIG. 4, the basic configuration of this non-radiative dielectric line is a dielectric having a rectangular cross section between parallel plate conductors 1 and 2 arranged in parallel with a predetermined interval a. The body line 3 is arranged such that the interval a is a ≦ λ / 2 with respect to the wavelength λ of the millimeter wave signal. As a result, the intrusion of noise from the outside to the dielectric line 3 can be eliminated, and the radiation of the millimeter wave signal to the outside can be eliminated, and the millimeter wave signal can be propagated through the dielectric line 3 with almost no loss. The wavelength λ is the wavelength of the millimeter wave signal in the air (free space) at the operating frequency.

The first, second and third dielectric lines 3, 4 and 5 may be made of resin such as tetrafluoroethylene and polystyrene, or cordierite (2MgO.2Al ₂ O ₃₎ having a low relative dielectric constant. Ceramics such as 5SiO ₂ ) ceramics, alumina (Al ₂ O ₃ ) ceramics, glass ceramics, etc. are preferable, and these have low loss in the millimeter wave band.

  The first, second and third dielectric lines 3, 4 and 5 are basically rectangular in cross section, but may be rounded at the corners of the rectangle. The thing of the various cross-sectional shape used for transmission of this can be used.

  In addition, the materials of the parallel plate conductors (plate conductors) 1 and 2 are Cu, Al, Fe, Ag, Au, Pt, SUS (stainless steel), brass in terms of high electrical conductivity and good workability. A conductor plate such as (Cu—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.

  The first, second and third transmission lines may be strip lines, microstrip lines, coplanar lines, grounded coplanar lines, slot lines, waveguides, dielectric waveguides, and the like. .

The ferrite plates 6 and 7 are preferably made of zinc, nickel and iron oxide (Zn _a Ni _b Fe _c O _x ), for example, for millimeter wave signals among ferrites.

  Further, the shape of the ferrite plates 6 and 7 is usually a disc shape, but the shape in plan view 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).

  As the antenna 8, a horn antenna, a slot antenna, a dielectric waveguide antenna, a patch antenna, an array antenna, or the like may be used.

  In addition, the shape of the through hole 9 provided in the flat conductor 1 or the flat conductor 2 may be normally rectangular, but may be other circular, oval, elliptical, polygonal, or the like. Absent.

  Next, a millimeter wave radar to which the first millimeter wave transceiver of the present invention using the first transmission / reception antenna of the present invention is applied will be described in detail.

  The configuration of the millimeter wave signal transmission unit in the millimeter wave radar to which the first millimeter wave transceiver of the present invention is applied is the same as that shown in the plan view of FIG. The basic configuration of the NRD guide as a dielectric line used in the configuration is the same as that shown in the partially broken perspective view of FIG.

  FIG. 5 is a block circuit diagram showing the configuration of the millimeter wave signal transmission unit and the intermediate frequency signal transmission unit for an example of an embodiment in which the first millimeter wave transceiver of the present invention is applied to a millimeter wave radar. FIG. 9 is a partially enlarged plan view in the vicinity of the third dielectric line in FIG. Hereinafter, an example of an embodiment of the first millimeter wave transceiver according to the present invention will be described. In addition, in the following description, when there exists a thing corresponding to the component shown in FIG. 6 in FIG. 5, the reference symbol in FIG.

  As shown in FIG. 6 and FIG. 5, the millimeter wave radar R1 using the first millimeter wave transmitter / receiver of the present invention is a flat conductor arranged in parallel at intervals of 1/2 or less of the wavelength of the millimeter wave signal. A millimeter wave signal oscillator (VCO) attached to a first dielectric line 53 between 51 and for modulating the frequency of a high frequency signal output from a high frequency diode and propagating the first dielectric line 53 as a millimeter wave signal 52 (21) and a pulse modulator (RF switch) interposed in the middle of the first dielectric line 53 to pulse the millimeter wave signal and output it from the first dielectric line 53 as a millimeter wave signal for transmission (22) and the first dielectric line 53 are arranged close to each other so that one end side is electromagnetically coupled, or one end is joined to the first dielectric line 53, and a part of the millimeter wave signal is mixed with the mixer 59 ( 25) The second dielectric line 58 propagating to the side and the inner surface of the flat conductor 51 The first connection portion 54a, the second connection portion 54b, and the second connection portion 54b are arranged radially at the periphery of the two ferrite plates disposed opposite to each other and are used as the input / output ends of the millimeter wave signal, respectively. A circulator 54 (23) that outputs a millimeter-wave signal input from one connection portion from one of the other connection portions adjacent to the first dielectric line 53. A circulator 54 (23) having a first connection portion 54a connected to the output end of the millimeter wave signal and a second connection portion 54b of the circulator 54 (23) are connected to propagate the millimeter wave signal and to the tip portion. The third dielectric line 55 having the antenna 56 (24) and the third connection part 54c of the circulator 54 (23) are connected to be received by the antenna 56 (24) and propagated through the third dielectric line 55. The received wave output from the third connection 54c is propagated to the mixer 59 (25). The fourth dielectric line 57, the middle of the second dielectric line 58, and the middle of the fourth dielectric line 57 are brought close to each other or joined so as to be electromagnetically coupled to each other. And a mixer 59 (25) for generating an intermediate frequency signal by mixing a part of the transmitting millimeter wave signal propagating through 58 and the received wave propagating through the fourth dielectric line 57, The line length of the third dielectric line 55 is propagated through the first dielectric line 53 of the transmitting millimeter wave signal output from the pulse modulator (22), and the third dielectric line 55 is transmitted through the first dielectric line 53. The signal is output from the first connection portion 54a through the second connection portion 54b to the third dielectric line 55, and is connected to the transmission / reception antenna 56 (24) which is the tip of the third dielectric line 55. A part of the millimeter wave reflected and leaked back to the circulator 54 (23) and leaked from the third connecting portion 54c to the fourth dielectric line 57 The other part of the millimeter wave signal leaked from the first connection part 54a directly to the third connection part 54c via the circulator 54 (23) is assumed to be Wb. When the phase difference at the center frequency between Wa and another part of the millimeter wave signal Wb is δ, the line length of the third dielectric line 55 is δ = (2N−1) · π (where N Is an integer. ).

  That is, the high frequency signal output from the high frequency diode is frequency-modulated between the parallel plate conductors 51 arranged at intervals of 1/2 or less of the wavelength of the millimeter wave signal and attached to the first dielectric line 53. A millimeter wave signal oscillating unit (VCO) 52 (21) for propagating the first dielectric line 53 as a millimeter wave signal, and intervening in the middle of the first dielectric line 53, pulse the millimeter wave signal for transmission. A pulse modulator (RF switch) (22) that outputs a first millimeter wave signal from the first dielectric line 53 and the first dielectric line 53 are arranged close to each other so that one end side is electromagnetically coupled, or the first One end of the dielectric line 53 is joined to the second dielectric line 58 for propagating a part of the millimeter wave signal to the mixer 59 (25) side, and the ferrite plate disposed in parallel to the parallel plate conductor 51 Are arranged at predetermined intervals on the periphery of the A first connection portion 54a, a second connection portion 54b, and a third connection portion 54c, which are input / output ends of signals, have a millimeter wave signal input from one connection portion within the plane of the ferrite plate. And a circulator 54 (23) that outputs from another connection part adjacent in the clockwise or counterclockwise direction, and the first connection part 54a is connected to the output end of the millimeter wave signal of the first dielectric line 53. A circulator 54 (23), and a third dielectric line 55 connected to the second connection portion 54b of the circulator 54 (23), for propagating a millimeter-wave signal and having an antenna 56 (24) at the tip, The third connection 54c is connected to the third connection 54c of the circulator 54 (23), is received by the antenna 56 (24), propagates through the third dielectric line 55, and passes through the second connection 54b. A fourth dielectric line 57 for propagating the reception wave output from the mixer 59 (25); The middle part of the dielectric line 58 and the middle part of the fourth dielectric line 57 are made close to each other or joined so as to be electromagnetically coupled, and the millimeter wave signal for transmission that has propagated through the second dielectric line 58 is transmitted. A mixer 59 (25) that mixes a part of the received wave propagated through the fourth dielectric line 57 and generates an intermediate frequency signal is provided, and is opened at the output end of the mixer 59 (25). A switch (IF) that shuts off the intermediate frequency signal in the OFF state and closes (ON) when the transmitting millimeter-wave signal output from the pulse modulator (22) is stable and passes the intermediate frequency signal. Switch) (26) is provided.

  In this example, the switch (26) for switching the intermediate frequency signal generated at the output terminal of the mixer 59 (25) has a timing generator (IF switch controller) for controlling the switching time of the switch 26. (29) is connected, and an amplifier (AMP) (28) for amplifying an intermediate frequency signal output through the switch 26 and output after the switch (26) is provided.

  The switch (26) is closed (on) when the pulsed millimeter wave signal for transmission is output from the pulse modulator (22), and after the output of the millimeter wave signal ends and falls, it becomes stable. State. In order to control the opening / closing of the switch (26) according to the stability of the millimeter wave signal for transmission in this way, the state of the millimeter wave signal for transmission is monitored to control the opening / closing of the switch (26). Alternatively, for example, the modulation signal of the pulse modulator (22) may be used to close the switch (26) when the modulation current is stabilized.

  The millimeter wave signal oscillating unit 52 (21) is, for example, a VCO (voltage controlled oscillator) provided with a Gunn diode and a varactor diode, and a signal is input to the IN-2 terminal for inputting a modulation signal. Operates as an oscillator. By inputting the output signal of the VCO of the millimeter wave signal oscillating unit 52 (21) and the pulsed signal input to the IN-1 terminal to the pulse modulator (22), the pulse is modulated by the pulse modulator (22). A modulated and pulsed millimeter wave signal for transmission is output.

  The pulse modulator (22) is interposed in the middle of the first dielectric line 53 in FIG. 6, and is an RF switch configured in the same manner as shown in FIG. 8, for example. The configuration is such that a choke-type bias supply line 90 is formed on one main surface of the substrate 88, and a beam lead type or flip chip type solder-mounted between connection electrodes 81, 81 formed in the middle. The switch is provided with a PIN diode or a Schottky barrier diode 80, and the Schottky barrier diode 80 is applied between the end faces in the middle of the first dielectric line 53 so that the application direction of the bias voltage crosses the line direction. It was installed in.

  A circulator 54 (23) propagates a millimeter wave signal to the antenna 56 (24) side during transmission and propagates a received wave to the mixer 59 (25) side during reception. 56 (24) is an antenna for transmitting and receiving millimeter wave signals. For example, it is connected to the circulator 54 (23) via a metal waveguide or a dielectric waveguide in which a metal is filled with a dielectric. A horn antenna or the like. Further, the mixer 59 (25) mixes the millimeter wave signal output from the VCO of the millimeter wave signal oscillating unit 52 (21) with the received wave received by the antenna 56 (24), so that the distance to the target is reached. An intermediate frequency signal for detecting the above is output.

  26 is a switch provided at the output end of the mixer 59 (25) that blocks the intermediate frequency signal output from the mixer 59 (25) in the open (off) state and passes it in the closed (on) state ( IF switch). A timing generator 29 generates a timing signal for controlling the opening / closing (on-off) timing of the switch (26).

  28 is an amplifier with a control terminal connected to amplify the intermediate frequency signal output from the millimeter wave transmitter / receiver after the switch (26), and a control signal is input from the outside through the control terminal. Then, the gain and operation of the amplifier (28) are temporally controlled. The control period of the amplifier (28) is determined by, for example, the digital state of the pulse signal input to the pulse modulator (22), and the input intermediate frequency signal is controlled for a desired period at a desired timing. It is comprised so that it may amplify.

  The timing generator (29) receives the pulse signal of the IN-1 terminal and the pulse signal of the control terminal so as to be interlocked with the control signals of the pulse modulator (22) and the amplifier (28). 22) The transmission millimeter wave signal pulse-modulated in (22) is reflected at the connection between the NRD guide and the dielectric waveguide or leaks from the circulator 54 (23) and is passed through the mixer 59 (25) as an unnecessary signal. The timing is controlled so as to be cut off by the switch (26) before being output to the amplifier (28).

  In the first millimeter wave transmitter / receiver of the present invention, the transmitting millimeter wave signal output from the pulse modulator (22) propagates through the first dielectric line 53, and the circulator 54 ( 23) is output to the third dielectric line 55 from the first connection part 54a through the second connection part 54b, and is connected to the antenna 56 (24) which is the tip of the third dielectric line 55. A part of the millimeter wave signal reflected from the section 55a and returned to the circulator 54 (23) and leaked from the third connection section 54c to the fourth dielectric line 57 is defined as Wa, and the circulator is connected to the circulator from the first connection section 54a. The other millimeter wave signal leaked directly to the third connection portion 54c via 54 (23) is defined as Wb, and the partial millimeter wave signal Wa and the other partial millimeter wave signal Wb When the phase difference at the center frequency is δ, the line length of the third dielectric line 55 is δ = (2N−1) · π (However, N is an integer.)

Further, in the first millimeter-wave transceiver of the present invention, as will be described later, the difference in characteristic impedance between the third dielectric line 55 and the antenna 56 (24) is adjusted, and a part of them is adjusted. with a 0.27 or a ratio R _p of the millimeter wave signal Wa and the power of the other portion of the millimeter wave signal Wb, = the phase difference δ δ (2N-1) · π ± 0.42π ( although, N is the It is preferably an integer.)

  The configuration and operation from the pulse modulator (22) to the mixer 59 (25) including the characteristic part in the millimeter wave radar R1 using the first millimeter wave transceiver of the present invention will be described in detail.

A millimeter wave signal is generated by a millimeter wave signal oscillating unit (VCO) 52 (21) and subjected to frequency modulation. Then, the millimeter wave signal is branched by a coupler (30), and a part of the branched is a pulse modulator (22). ) And modulated as a millimeter wave signal for transmission. The millimeter wave signal for transmission propagates through the first dielectric line 53 and enters the circulator 54 (23) from the first connection portion 54a, and a part of the millimeter wave signal is originally isolated from the circulator 54 (23). Leakage from the third connection part 54c through the rated path (from the first connection part 54a to the third connection part 54c) or output from the second connection part 54b and the third dielectric line 55 is propagated through and reflected by the antenna 56 (24) at the incident end or the antenna 56 (24), propagates again through the third dielectric line 55, and enters the circulator 54 (23) from the second connection portion 54b. Then, it leaks from the third connection portion 54c, or becomes the millimeter wave signal input P _RF that propagates through the fourth dielectric line 57 and enters the mixer 59 (25). On the other hand, the other part of the millimeter wave signal branched by the coupler (30) becomes the millimeter wave signal input P _LO incident on the mixer 59 (25) through the second dielectric line 58 as the local path. . Their millimeter wave signal input _{P RF} and millimeter-wave signal input _{P LO} and _{P RF} and _{P LO,} respectively, if the output of the intermediate frequency signal output from the mixer 59 (25) and _{P MIX} and [Delta] P _MIX its variation, The output P _MIX of the mixer 59 (25) and its variation ΔP _MIX are respectively expressed by the following equations.

P _MIX = (P _RF · P _LO · sin δ · Gc) ^1/2 (1)
ΔP _MIX = (1/2) · (P _RF · P _LO · cos δ · Gc) ^1/2 (2)
However, [delta] is the phase difference at the center frequency of the P _RF and P _LO, Gc is the conversion gain in the mixer 59 (25).

_Further, the following expression between the _{P MIX} is also changed by a change in _{P RF} or _{P LO} itself are respectively represented by [Delta] P _RF or [Delta] P _LO, millimeter wave input _{P in} to the [Delta] P _RF and pulse modulator (22) There is a relationship.

ΔP _RF = P _in · η · ΔV _SW · α · β (3)
However, ΔV _SW is a fluctuation of the driving voltage of the pulse modulator (22), and represents a fluctuation component due to a transient response, α is an ON / OFF ratio of the pulse modulator (22), and β is a circulator 54 (23 ) Between the first connection portion 54a and the third connection portion 54c (however, the reflection component from the antenna 56 (24) is also included). Η represents the ratio of the output fluctuation ΔP of the pulse modulator 22 to ΔV _{SW as} shown in the following equation.

η = ΔP / ΔV _SW (4)
In the millimeter wave radar R1, in order to make ΔP _MIX sufficiently small, any one of the expressions (2), (3), and (4) may be reduced. Of these, P _RF is used as a millimeter wave for transmission. Among the signals, a part of the millimeter wave signal which passes through the third dielectric line 55 and is reflected by the connection portion 55a with the antenna 56 (24) which is the tip of the signal and leaks back to the third connection portion 54c. If it is made small by using interference between the millimeter wave signal Wb leaking directly from the first connection portion 54a to the third connection portion 54c from the first connection portion 54a via the circulator 54 (23), it relates to the millimeter wave transmission / reception performance. This is convenient because it can be easily designed without affecting the P _in , η or Gc, and without changing the ΔV _SW , α or β which is difficult in principle.

In order to reduce the P _RF by utilizing interference between some of the millimeter wave signals Wa and some of the other millimeter wave signals Wb, the signal intensity (power) of some of the millimeter wave signals Wa and other parts Are equalized with the signal intensity (power) of the millimeter wave signal Wb, and they are made to interfere with each other with the opposite phase, that is, the phase difference δ as δ = (2N−1) · π (N is an integer). Good. This is equivalent to adjusting the line length of the third dielectric line 55 and setting the phase change when the millimeter wave signal propagates back and forth through the third dielectric line 55 to (2N−1) · π. . Specifically, the line length of the third dielectric line 55 can be controlled by changing the length, width, relative permittivity of the third dielectric line 55, and the like. Further, impedance matching for the millimeter wave signal at the connection portion 55a with the antenna 56 (24) which is the tip of the third dielectric line 55, that is, the characteristic impedance between the third dielectric line 55 and the antenna 56 (24). By changing the reflection coefficient at the connection portion 55a by adjusting the difference between the signal strengths of some of the millimeter wave signals Wa so as to be substantially equal to the signal strength (power) of some of the other millimeter wave signals Wb. (Power) can be adjusted. The reflection coefficient at the connection portion 55a is the size of the connection portion 55a and the dielectric constant of the dielectric, which are the factors causing the difference in characteristic impedance, or between the third dielectric line 55 and the antenna 56 (24). If there is an inclusion such as a waveguide, it can be adjusted by adjusting the size and dielectric constant of the inclusion.

_PRF is minimized when the line length of the third dielectric line 55 is set to be δ = (2N−1) · π, and is set to be δ = (2N) · π. Therefore, the output fluctuation ΔP _MIX of the mixer 59 (25) becomes the maximum when δ = (2N) · π, and the millimeter wave transmission / reception performance becomes worst, and δ = (2N−1) · π Sometimes it is minimized and the millimeter wave transmission / reception performance is the best.

This will be described with reference to FIG. 9 and FIG. FIG. 9 is a partially enlarged plan view of the vicinity of the third dielectric line 55 in FIG. 6, and FIG. 10 shows an antenna 56 which is the tip of the third dielectric line 55 through the third dielectric line 55. (24) and a part of the millimeter-wave signal Wa that is reflected by the connection portion 55a and leaks back to the third connection portion 54c, and the third connection portion 54a from the first connection portion 54a through the circulator 54 (23). It is a graph which shows the change of the output intensity of a millimeter wave signal by phase difference (delta) when another part of millimeter wave signal Wb leaking to the connection part 54c interferes and combines. In FIG. 9, Wa represents a part of the millimeter wave signal reflected from the connection portion 55a of the third dielectric line 55 with the antenna 56 (24) and leaked back to the third connection portion 54c. It represents another part of the millimeter wave signal leaking from the first connection portion 54a directly to the third connection portion 54c via the circulator 54 (23). Since the millimeter wave signal for transmission incident on the first connection portion 54a through the first dielectric line 53 is isolated between the first connection portion 54a and the third connection portion 54c. Most of the power is transmitted to the second connection portion 54b side and radiated from the antenna 56 (24) through the third dielectric line 55. At this time, a part of the millimeter wave signal is slightly reflected by the connecting portion 55a due to a slight mismatch in impedance at the connecting portion 55a with the antenna 56 (24) which is the tip of the third dielectric line 55. The third dielectric line 55 is returned again and leaks as Wa to the third connection portion 54c through the circulator 54 (23). On the other hand, the millimeter wave signal for transmission incident on the first connection portion 54a through the first dielectric line 53 is isolated between the first connection portion 54a and the third connection portion 54c. Although slightly, a part of the power leaks from the first connecting portion 54a to the third connecting portion 54c as another part of the millimeter wave signal Wb. Here, the electric field strength of some of the millimeter wave signals Wa is E _a , the electric field strength of some other millimeter wave signals Wb is E _b , and the other one that is a millimeter wave signal leaking from the third connection portion 54 c. if part of the millimeter wave signal Wb and the output intensity of a portion of the millimeter wave signal Wa and combined with interference millimeter-wave signal (power) and P _i, P _i is expressed by the following equation. Incidentally, the electric field strength E _a and E _b represents the electric field intensity just after entering the third connecting portion 54c to the fourth dielectric waveguide 57, respectively.

P _i = (1/2) · (| E _a | − | E _b |) ² +2 | E _a || E _b | cos ² (δ / 2) (5)
In addition, the power ratio R _p is changed to a power division ratio r _p .
r _p = (| E _a | / | E _b |) ² (6)
In addition, _Pi is

However,
P ₀ = | E _a | ² + | E _b | ² (8)
It can be expressed as.

here,
P _i <| E _b | ² (9)
If so, the millimeter wave signal P _i leaking from the third connection portion 54c is the signal intensity of the original part of the millimeter wave signal Wa even if another part of the millimeter wave signal Wb is combined. It can be attenuated more than | E _b | ² .

Thus, in the formula (7) may be set power split ratio r _p and δ that satisfies this condition.

At this time, from equation (6),
| E _b | ² = r _p · | E _a | ²
And substituting this into equation (8),
| E _b | ² = P ₀ / (1 + r _p )
It becomes. Substituting this into equation (9) and expressing the power division ratio r _p as the ratio of the power of some of the millimeter wave signals Wa and some of the other millimeter wave signals Wb by R _p yields the following equation: .

  By satisfying the condition of the expression (10), some millimeter wave signals Wa and other some millimeter wave signals Wb interfere so as to weaken each other, and some millimeter wave signals Wa and other ones The intensity of the millimeter wave signal combined by interference with the part of the millimeter wave signal Wb is suppressed to be smaller than the intensity of the other part of the millimeter wave signal Wb before the interference.

  Next, the optimum condition in equation (10) will be described using equation (7) and FIG.

As shown in FIG. 10, P _i represented by the equation (7) indicates a characteristic that repeats a maximum value and a minimum value in a π period according to a change in δ. The horizontal axis in FIG. 10 is a phase difference [delta] (unit: radian) and the vertical axis represents the millimeter-wave signal P _i leaked from the third connecting portion 54c, the characteristic curve represents the variation of P _i by [delta]. The broken line represents the maximum value and the minimum value of the characteristic curve. From Figure 10, the millimeter-wave signal P _i leaked from the third connecting portion 54c is, [delta] is ± π, ± 3π, ···, (2N-1) π (N is an integer.) Minimum when the It can be seen that the maximum value is obtained when δ is 0, ± 2π,..., 2Nπ. Further, when the power division ratio r _p is r _p = 1, that is, when | E _a | and | E _b | are equal, the minimum value of the signal intensity P _i of the millimeter wave signal leaking from the third connection portion 54c is Theoretically, it can be seen that it approaches zero as much as possible.

Accordingly, the signal intensity (power) of some of the millimeter wave signals Wa and the signal intensity (power) of some of the other millimeter wave signals Wb are made equal to each other, and they are reversed in phase, that is, the phase difference (2N−1). ) · Π can be interfered with until P _{i represented} by Equation (5) or Equation (7) is nearly zero, and P _RF corresponding to P _i is suppressed in Equation (2). Therefore, the mixer output fluctuation ΔP _MIX is the smallest and well suppressed.

Further, when the mixer output fluctuation ΔP _MIX is the smallest and satisfactorily suppressed, the level fluctuation as described in the problem to be solved by the invention immediately settles and stabilizes in a steady state. Therefore, from the pulse modulator (22) The mixer 59 is provided in a conventional manner by a switch (26) provided so that the output millimeter wave signal for transmission can be blocked by being directly mixed into the mixer 59 (25) by reflection or the like and output to the receiving system. Even unnecessary signals generated in (25) do not need to be cut off, and immediately after sending a pulse signal, it is possible to start the millimeter wave transmission / reception in the closed (on) state.

  Although the theoretical optimum conditions have been described above, actually, the signal strength (power) of some of the millimeter wave signals Wa and the signal strength (power) of some of the other millimeter wave signals Wb are substantially equal. In the above, the line length of the third dielectric line 55 may be set so that they are almost in reverse phase.

  Next, the range of the line length of the third dielectric line 55 that is more useful in actual use will be described.

  First, it is assumed that the electric field strength of some millimeter wave signals Wa is smaller than the electric field strength of some other millimeter wave signals Wb. This is also considered because some millimeter wave signals Wa are originally to be transmitted from the antenna 56 (24).

At this time, the third output intensity P _i maximum value and the minimum value relative attenuation factor of the E _r Tosureba attenuation factor E _r of the millimeter-wave signal leaking from the connection portion 54c is greater than 1/2 (3 dB) if so, the output intensity (power) P _i of the third millimeter-wave signal output leaking from the connection portion 54c is, another part of the millimeter-wave signal Wb is a part of the millimeter wave signal Wa interference At least the length of the third dielectric line 55 can be made smaller than the strength (power) that it had before, when the phase difference δ is δ = (2N−1) · π. . Here, when the attenuation rate _Er is close to ½ (3 dB), the output intensity (power) P _{i of the} millimeter wave signal leaked and output from the third connection portion 54c is equal to some other millimeters. The range in which the line length of the third dielectric line 55 can be set is very narrow so that the wave signal Wb becomes smaller than the strength (power) that it had before it interfered with some millimeter wave signals Wa. Only δ = (2N−1) · π is an effective condition. Therefore, the attenuation rate E _r may be made larger than that so that E _r = 1/2 (3 dB).

The attenuation rate _Er is

Therefore, the power division ratio r _p is calculated from the equation (11), and the equation (11) is transformed into an equation for obtaining r _p and is substituted by E _r > 1/2. _p ≧ 0.03 may be set. Therefore, the signal strength (power) ratio R _p (power division ratio r _p ) between some of the millimeter-wave signals Wa and some of the other millimeter-wave signals Wb is almost always not controlled. In order to satisfy these conditions, if the line length of the third dielectric line 55 is set so that the phase difference δ is δ = (2N−1) · π, the third dielectric line 55 leaks from the third connection portion 54c. the ability to suppress the output intensity P _i of the millimeter-wave signal output.

  In this case, however, the line length of the third dielectric line 55 may be strictly set because it is necessary to strictly set the phase difference δ to be δ = (2N−1) · π.

Next, the attenuation rate _Er when the millimeter wave signals are caused to interfere with each other is empirically determined by interfering two electromagnetic waves so that the combined electromagnetic waves are attenuated. E _r = 10 dB as a value that is a sufficient attenuation factor when obtaining the attenuation of the electromagnetic wave that has been waved (attenuate to 1/10 of the total power of the two electromagnetic waves before the power of the wave that has been combined is combined) It is known that it is relatively easy to set the attenuation ratio.) If the power division ratio r _p is set from now on, it is calculated from the equation (7) that r _p ≈0.27. . At this time, the phase difference δ in the equation (6) may be determined so that P _i <(1/2) P _0, and the phase difference δ is determined based on a part of the millimeter wave signal Wa and another part of the millimeter wave. The signal strength (power) ratio R _p (power division ratio r _p ) to the signal Wb is set to 0.27 or more, and δ = (2N−1) · π ± 0.42π (where N is an integer). It is guided that it should be set.

In this case, the accuracy of the phase difference δ set according to the line length of the third dielectric line 55 becomes ± 0.42π, and the manufacture becomes easy, so that it is easy to realize a practically good characteristic. On the other hand, also in this case, when the phase difference δ is set to δ = (2N−1) · π, the output intensity (power) P of the millimeter wave signal that is most leaked and output from the third connection portion 54c. _i , that is, the millimeter wave signal input P _RF leaking from the third connection portion 54c, propagating through the fourth dielectric line 57 and entering the mixer 59 (25) is reduced, and the mixer output fluctuation ΔP _MIX is suppressed. Therefore, it goes without saying that the level fluctuation as described in the problem to be solved by the invention is immediately settled and stabilized in a steady state, and the millimeter wave transmission / reception characteristics are improved.

To actually adjust the conditions described above, the output intensity of the millimeter wave signal from the fourth dielectric line 57 when the line length of the third dielectric line 55 is changed is measured with a power meter. If the maximum and minimum values of the characteristic curve shown in FIG. 10 are read from the measured data, the attenuation rate _Er can be obtained and the power split ratio r _p (corresponding to R _p ) can be obtained and shown in FIG. The phase difference δ can be determined from the repetition period of the maximum and minimum values of the characteristic curve. Based on these, the line length of the third dielectric line 55 is satisfied so as to satisfy the condition of the above equation (10). And the difference in characteristic impedance at the connecting portion 55a between the third dielectric line 55 and the antenna 56 (24) may be adjusted.

As described above, according to the first millimeter-wave transceiver of the present invention, the transmission millimeter-wave signal output from the pulse modulator (22) propagates through the first dielectric line 53, and An antenna 56 (24) which is output from the first connection portion 54a of the circulator 54 (23) to the third dielectric line 55 through the second connection portion 54b and is the tip of the third dielectric line 55. A part of the millimeter wave signal reflected from the connecting portion 55a to the circulator 54 (23) and leaking from the third connecting portion 54c to the fourth dielectric line 57 is defined as Wa, and the first connecting portion Other millimeter wave signals leaking directly from the 54a to the third connection portion 54c via the circulator 54 (23) are defined as Wb, and these partial millimeter wave signals Wa and other partial millimeter wave signals. When the phase difference at the center frequency with respect to Wb is δ, the line length of the third dielectric line 55 is δ = (2N−1) · π (However, N is an integer.) Preferably, the ratio R _p of the power of these part of the millimeter wave signals Wa and the other part of the millimeter wave signals Wb is set to Since the phase difference δ is set to 0.27 or more and δ = (2N−1) · π ± 0.42π, the pulse-modulated millimeter-wave signal for transmission is reflected inside the millimeter-wave transceiver. In a millimeter wave transmitter / receiver with a switch (26) that can shut off the output to the receiving system due to, etc., transmission and reception can be performed immediately after sending a pulse signal. It is possible to provide a millimeter-wave radar that can improve the radar detection performance when it is present, and that is particularly excellent in short-range radar detection performance.

  In addition, since the first transmission / reception antenna of the present invention is used, it is possible to suppress a part of the millimeter wave signal from leaking to the reception system and reduce interference with the millimeter wave signal to be received. The reception characteristics of the reception system of the millimeter wave transceiver can be improved. This also increases the power of the millimeter wave signal in the transmission system, thereby extending the transmission distance of the millimeter wave signal transmitted by the transmission / reception antenna, and improving the S / N (signal-to-noise) ratio. Overall, millimeter wave transmission / reception performance can be improved.

  Next, a millimeter wave radar to which the second millimeter wave transmitter / receiver of the present invention using the second transmit / receive antenna of the present invention is applied will be described in detail.

  The configuration of the millimeter wave signal transmission unit in the millimeter wave radar to which the second millimeter wave transceiver of the present invention is applied is the same as that shown in the plan view of FIG. The basic configuration of the NRD guide as a dielectric line used in the configuration is the same as that shown in the partially broken perspective view of FIG.

  FIG. 5 is a block circuit diagram showing the configuration of the millimeter wave signal transmission unit and the intermediate frequency signal transmission unit for an example of an embodiment in which the second millimeter wave transceiver of the present invention is applied to a millimeter wave radar. FIG. 2 is a plan view showing an example of a transmission / reception antenna used in the second millimeter-wave transceiver of the present invention. Hereinafter, an example of an embodiment of the second millimeter wave transceiver according to the present invention will be described. In addition, in the following description, when there exists a thing corresponding to the component shown in FIG. 7 in FIG. 5, the referential mark in FIG.

  As shown in FIGS. 7 and 5, the millimeter wave radar R2 using the second millimeter wave transmitter / receiver of the present invention is a flat conductor arranged in parallel at an interval of 1/2 or less of the wavelength of the millimeter wave signal. 2 is attached to the transmission / reception antenna shown in FIG. 2 and the first dielectric line 53. The high-frequency signal output from the high-frequency diode is frequency-modulated and propagated through the first dielectric line 53 as a millimeter-wave signal. A millimeter wave signal oscillating unit (VCO) 52 (21) and a first dielectric line 53 are interposed, and the millimeter wave signal is pulsed and output from the first dielectric line 53 as a millimeter wave signal for transmission. A pulse modulator (RF switch) (22) to be connected to the first dielectric line 53 so that one end side thereof is electromagnetically coupled, or one end is joined to the first dielectric line 53, and the millimeter wave 4th invitation to propagate part of signal to mixer 59 (25) The body line 57 and the middle part of the fourth dielectric line 57 and the middle part of the second dielectric line 58 are brought close to each other or joined so as to be electromagnetically coupled, and propagates through the fourth dielectric line 57. And a mixer 59 (25) for generating an intermediate frequency signal by mixing a part of the transmitted millimeter wave signal and the received wave propagating through the second dielectric line 58.

In the second millimeter-wave transceiver of the present invention, as described above, the third dielectric line 55 and the antenna connected to the through-hole 9 or the waveguide or the primary connected to the antenna are also used. The difference in characteristic impedance with the radiator is adjusted so that the power ratio R _p between these part of the millimeter wave signal Wa and the other part of the millimeter wave signal Wb is 0.27 or more, and the phase difference δ is made δ = (2N-1) · π ± 0.42π (where N is an integer).

  Also, a switching control unit that opens the output end when a pulse-modulated millimeter-wave signal for transmission is output from the pulse modulator (RF switch) (22) to the output end of the mixer 59 (25). Is preferably provided.

  With the above configuration, in the second millimeter-wave transceiver of the present invention, the transmission millimeter-wave signal propagating through the third dielectric line 55 is transmitted through the through-hole 9, and one of the transmission millimeter-wave signals is transmitted. Except that the portion is reflected by the through-hole 9, it has the same function and effect as the first millimeter-wave transceiver of the present invention.

  That is, according to the second millimeter-wave transmitter / receiver of the present invention, since it has the above-described configuration, it is possible to suppress a part of the millimeter-wave signal in the transmission system from leaking to the reception system, and the millimeter wave to be received. Since interference with wave signals can be reduced, the reception characteristics of the reception system of the millimeter wave transceiver can be improved. This also increases the power of the millimeter wave signal in the transmission system, thereby extending the transmission distance of the millimeter wave signal transmitted by the transmission / reception antenna, and improving the S / N (signal-to-noise) ratio. Overall, millimeter wave transmission / reception performance can be improved. In the second millimeter wave transceiver according to the present invention, an antenna or a waveguide or a primary radiator connected to the antenna is connected to the through hole 9 of the flat conductor 2, so that the millimeter wave transceiver is a module. Therefore, there is an advantage that the antenna can be accommodated on the flat conductor, and the module can be configured in a small size.

  Thus, according to the transmission / reception antenna of the present invention and the millimeter wave transmitter / receiver of the present invention using the transmission / reception antenna, the transmission / reception antenna capable of suppressing leakage of a part of the millimeter wave signal of the transmission system directly to the reception system and the same Therefore, it is possible to provide a millimeter wave transmitter / receiver having a high millimeter wave transmission / reception performance.

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, in the millimeter wave radar R1 which is an example of the embodiment of the present invention, the first NRD guide in which a dielectric line is disposed between the first and second parallel plate conductors 51 which are the parallel plate conductors 51. An opening is provided in the parallel plate conductor, and one end of the third dielectric line 55 and the antenna 56 (24) are connected to each other through the opening and the waveguide or dielectric waveguide connected to the opening. The length from the other end of the third dielectric line 55 to the opening along the third dielectric line 55 is δ = (2N−1) · π (where N is an integer). It is good also as a structure set so that it may become. In this case, the mixer output fluctuation ΔP _MIX is suppressed, and excellent millimeter wave transmission / reception performance is obtained. In addition, an electromagnetic wave for millimeter wave transmission / reception is transmitted from the antenna 56 (24) provided on the first parallel plate conductor. The radiation can be emitted toward the upper side of the first conductive plate, and the millimeter wave radar R1 as a module can be mounted on the mounting target using the side surface substantially parallel to the second conductive plate as the mounting surface. Usually, since a millimeter wave radar module is configured by arranging a plurality of parts such as a dielectric line constituting a millimeter wave circuit between the parallel plate conductors of the parallel plate conductor 51, a large area parallel to the parallel plate conductor is formed. If the main surface of the millimeter wave radar module is provided and this surface can be used as a mounting surface, a stable attachment state to the mounting object can be obtained. For example, in the case of in-vehicle use, the millimeter wave radar R1 is firmly attached to the front part or the rear part of the vehicle, and the millimeter wave signal can be easily transmitted and received toward other vehicles such as the front or rear.

It is a schematic diagram which shows an example of embodiment of the 1st transmission / reception antenna of this invention, (a) is a top view, (b) is the A-A 'sectional drawing. It is a schematic diagram which shows an example of embodiment of the 2nd transmission / reception antenna of this invention, (a) is a top view, (b) is the B-B 'sectional drawing. FIG. 3 is a schematic diagram showing the dependence of the isolation characteristic of the transmission / reception antenna shown in FIG. 1 or 2 on the phase difference δ. It is a partially broken perspective view which shows the basic composition of a NRD guide. It is a block circuit diagram which shows the structure of the millimeter wave signal transmission part and intermediate frequency signal transmission part about an example of the embodiment at the time of applying the millimeter wave transceiver of this invention to a millimeter wave radar. It is a top view of the millimeter wave transceiver which has a transmission / reception antenna. It is a top view which shows typically an example of embodiment of the 2nd millimeter wave transmitter-receiver of this invention. It is a perspective view which shows the structure of the pulse modulator of a millimeter wave transmitter / receiver. FIG. 7 is a partially enlarged plan view of the vicinity of a third dielectric line in FIG. 6 in the millimeter wave transceiver according to the present invention. A part of the millimeter wave signal Wa that passes through the third dielectric line, reflects off the connecting portion with the antenna at the tip thereof, and returns to the third connecting portion, and the circulator from the first connecting portion. 8 is a graph showing a change in the output intensity of the millimeter wave signal due to the phase difference δ when the other millimeter wave signal Wb leaking to the third connection portion interferes and is combined. It is a block circuit diagram which shows the structure of each part when the conventional millimeter wave transmitter-receiver is used as a millimeter wave radar. It is a typical top view which shows the example of the conventional transmission / reception shared radiator.

Explanation of symbols

1, 2: flat conductor 3: first dielectric line 3a: one end 3c: first connection part 4: second dielectric line 4a: one end 4c: second connection part 5: third dielectric line 5a: One end 5b: The other end 5c: Third connection portion 6, 7: Ferrite plate 8: Antenna 9: Through hole
21: Millimeter wave signal oscillator
22: Pulse modulator (RF switch)
23: Circulator
24: Antenna
25: Mixer
26: Switch (IF switch)
28: Amplifier
29: Timing generator
30: Coupler (directional coupler)
51: Flat conductor (parallel flat conductor)
52: Millimeter wave signal oscillator
53: First dielectric line
54: Circulator
55: Third dielectric line
56: Antenna
57: Fourth dielectric line
58: Second dielectric line
57a, 58a: Non-reflective terminator
59: Mixer C: Circulator R1, R2: Millimeter wave radar

Claims (6)

First, second, and third transmission lines that transmit millimeter-wave signals are radially connected to the peripheral portion of the magnetic material at the first, second, and third connection portions, respectively, and input from one of the connection portions. In addition, a circulator that outputs the millimeter wave signal from one of the other connecting portions adjacent to the antenna, and an antenna is connected to the other end of the third transmission line having one end connected to the third connecting portion. An antenna, the length of the third transmission line being reflected by the antenna through the third transmission line and returning to the second connection portion as a part of the millimeter wave signal Wa The other part of the millimeter wave signal leaked from the first connection part to the second connection part through the circulator is defined as Wb, and the phase difference at the center frequency between these Wa and Wb is defined as δ. Sometimes δ = (2N−1) · π (where Reception antennas N, characterized in that set to be an integer.). Two ferrite plates are arranged between the flat plate conductors arranged in parallel at intervals of one half or less of the wavelength of the millimeter wave signal so as to face each other on the inner surface of the flat plate conductor. First, second, and third dielectric lines that input and output the millimeter-wave signal radially are connected to the peripheral portion by first, second, and third connecting portions, respectively, and input from one of the connecting portions. In addition, the circulator that outputs the millimeter wave signal from one of the other connecting portions adjacent to the circulator has an LSM mode standing wave electric field of the third dielectric line having one end connected to the third connecting portion. A transmission / reception antenna in which a through hole is provided in one of the flat plate conductors at a site facing a strong location, and an antenna or a waveguide or primary radiator connected to the antenna is connected to the through hole, The one end of the dielectric line of 3 A part of the millimeter wave signal leaked to the second connection portion after being reflected by the through hole through the third dielectric line and returning to the second connection portion. The other part of the millimeter wave signal leaked from the first connection part to the second connection part through the circulator is defined as Wb, and the phase difference at the center frequency between these Wa and Wb is defined as δ. Sometimes, the transmission / reception antenna is set such that δ = (2N−1) · π (where N is an integer). Between flat conductors arranged in parallel at intervals of half or less of the wavelength of the millimeter wave signal,
A millimeter-wave signal oscillating unit that is attached to the first dielectric line, modulates a high-frequency signal output from the high-frequency diode, and propagates the first dielectric line as a millimeter-wave signal;
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;
Second end is disposed close to the first dielectric line so that one end side is electromagnetically coupled, or one end is joined to the first dielectric line to propagate a part of the millimeter wave signal to the mixer side. A dielectric line of
A first connecting portion and a second connecting portion are arranged radially at the peripheral portions of the two ferrite plates disposed opposite to each other on the inner surface of the flat conductor, and serve as input / output ends of the millimeter wave signal, respectively. A circulator that has a connection portion and a third connection portion, and outputs the millimeter wave signal input from one of the connection portions from one of the other adjacent connection portions; A circulator in which the first connection portion is connected to an output end of the millimeter wave signal on a line;
A third dielectric line connected to the second connection part of the circulator, for propagating the millimeter wave signal and having an antenna at a tip part;
A fourth dielectric connected to the third connecting portion of the circulator, received by the antenna and propagating through the third dielectric line, and propagating the received wave output from the third connecting portion to the mixer; Body track,
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 and the received wave are mixed. And a mixer for generating an intermediate frequency signal,
The line length of the third dielectric line is reflected from the tip part of the millimeter wave signal for transmission through the third dielectric line and returned to the third connection part. The millimeter wave signal of the part is denoted by Wa, and another part of the millimeter wave signal leaking from the first connection part to the third connection part via the circulator is denoted by Wb, and the center frequency of these Wa and Wb A millimeter wave transceiver characterized in that δ = (2N−1) · π (where N is an integer), where δ is the phase difference at. Between flat conductors arranged in parallel at intervals of half or less of the wavelength of the millimeter wave signal,
A transmitting and receiving antenna according to claim 2;
A millimeter-wave signal oscillating unit that is attached to the first dielectric line, modulates a high-frequency signal output from a high-frequency diode, and propagates the first dielectric line as a millimeter-wave signal;
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;
A fourth end is disposed close to the first dielectric line so that one end is electromagnetically coupled, or one end is joined to the first dielectric line to propagate a part of the millimeter wave signal to the mixer side. A dielectric line of
The middle part of the fourth dielectric line and the middle part of the second dielectric line are close to each other or joined so as to be electromagnetically coupled, and a part of the millimeter wave signal and reception received by the transmitting / receiving antenna A millimeter-wave transceiver comprising a mixer that mixes waves and generates an intermediate frequency signal. The power ratio of the partial millimeter wave signal Wa to the partial millimeter wave signal Wb is set to 0.27 or more, and the phase difference δ is set to δ = (2N−1) · π ± 0.42π (provided that , N is an integer.) The millimeter-wave transceiver according to claim 3 or 4, wherein: The switching control unit that opens the output terminal when the pulse-modulated millimeter-wave signal for transmission is output from the pulse modulator is provided at the output terminal of the mixer. The millimeter wave transceiver according to any one of claims 3 to 5.

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