JP3222964B2 - Vertical discontinuous leaky wave NRD guide - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vertically discontinuous leaky wave NRD guide capable of generating a higher electric field.

[0002]

2. Description of the Related Art NRD guides (Non-radiative dielectric lines, non-radiative
ielectric Waveguide) is known. This NRD guide has a structure in which a dielectric strip is sandwiched between upper and lower metal plates. Then, a discontinuous element such as a concave portion is provided on the dielectric strip, and by exciting the dielectric strip, a radio wave is generated between the upper and lower metals.

[0003]

Conventionally, a dielectric strip is provided with a concave portion for each radio wave propagation wavelength λg, and a leaky wave NRD guide is used as a discontinuous element.

However, since the electric power of the radio wave radiated from one concave portion is small, a large number of concave portions must be provided in order to radiate the radio wave efficiently.

For this reason, there is a problem that the leaky wave NRD guide must be lengthened. On the other hand, the leakage wave N
A leaky wave NRD guide has been proposed in which a dielectric strip of the RD guide is cut off as a discontinuous element of two pieces at a distance of λg / 4 one above and below as a discontinuous element at a distance of λg / 4 for generation of radio waves. However, there is a problem that the structure is complicated.

The present invention has been made in view of the above points, and an object of the present invention is to provide a vertically discontinuous type leaky wave NRD guide that can efficiently radiate radio waves even if the structure is simple and short. .

[0007]

According to a first aspect of the present invention, there is provided a vertical discontinuous type leaky wave NRD guide formed in a dielectric strip or a metal strip sandwiched between two vertically parallel metal plates. Two types of discontinuous elements are provided, and a dielectric having a dielectric constant higher than that of the dielectric strip is added to one discontinuous element, and a dielectric constant lower than that of the dielectric strip is added to the other discontinuous element. It is characterized in that a dielectric having a dielectric constant is added.

A vertically discontinuous leakage wave NR according to claim 2
The D guide is characterized in that the two types of discontinuous elements are alternately disposed at every λg / 2 on the dielectric strip or the metal plate.

A vertically discontinuous leaky wave NR according to claim 3
In the D guide, concave discontinuous elements are provided for each propagation wavelength λg on the upper and lower sides of a dielectric strip sandwiched and disposed between two vertically parallel metal plates. A dielectric having a dielectric constant higher than that of the dielectric strip is added, and a dielectric having a dielectric constant lower than that of the dielectric strip is added to the lower discontinuous element. .

A vertically discontinuous leakage wave NR according to claim 4
In the D guide, two types of concave discontinuous elements are alternately installed at every λg / 2 on the upper and lower sides of a dielectric strip sandwiched and arranged between two vertically parallel metal plates. A dielectric having a dielectric constant higher than that of the dielectric strip is added to the discontinuous element, and a dielectric having a dielectric constant lower than that of the dielectric strip is added to the other discontinuous element. It is characterized by.

A vertically discontinuous leakage wave NR according to claim 5
The D guide is provided with concave cuts for each propagation wavelength λg in the upper and lower metal plates of two vertically parallel metal plates sandwiching the dielectric strip. A dielectric having a dielectric constant higher than the dielectric constant is added, and a dielectric having a dielectric constant lower than that of the dielectric strip is added to the lower metal plate recess.

[0012]

The electric wave perpendicular to the metal plate of the NRD guide can be easily generated by simply constructing discontinuous elements at the same location of the leaky wave NRD guide, thereby realizing the radiation effect and the matching effect, and at the same time, one discontinuous element. An electric field higher than that of a continuous element can be generated.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of a basic NRD guide,
FIG. 2 is a cross-sectional view of one block of the vertical discontinuous leaky wave NRD guide according to the first embodiment of the present invention, FIG. 3 is a cross-sectional view of a dielectric strip of the vertical discontinuous leaky wave NRD guide,
FIG. 4 is a diagram showing the relationship between the depth of the cut provided in the dielectric strip and the amount of radio wave radiation.

First, the configuration of a basic NRD guide will be described with reference to FIG. A waveguide using a dielectric such as an NRD guide is advantageous in reducing a conductor loss due to a metal wall in a microwave or millimeter wave band.

As shown in FIG. 1, the NRD guide has a structure in which a dielectric strip 13 is sandwiched between parallel metal plates 11 and 12. The dimensions of the dielectric strip 13 are the height a. Those having a width b and the size of Equations 1 and 2 are used (λ
Is the free space wavelength, ε _r is the relative permittivity of the dielectric strip), and the material is a high-frequency low-loss material such as Teflon, polyethylene, or polystyrene.

[0016]

(Equation 1)

(Equation 2) In general, the transmission mode of a homogeneous NRD guide is a line that does not radiate in a hybrid mode, but in the present invention, a discontinuous element is provided on a dielectric strip to transmit radio waves between the parallel metal plates 11 and 12. The present invention relates to a leaky wave NRD guide that radiates and is used for an antenna or a coupling line.

Next, with reference to FIG. 2, the configuration of one block of the upper and lower discontinuous type leaky wave NRD guide according to the first embodiment of the present invention will be described. As shown in FIG. 2, a dielectric strip 23 is sandwiched between an upper metal plate 21 and a lower metal plate 22. This dielectric strip 23 is provided with a pair of concave discontinuous elements 24 and 25 on the upper surface and the lower surface.

A dielectric having a dielectric constant ε ₁ higher than the dielectric constant ε ₂ of the dielectric strip 23 is added to the upper concave discontinuous element 24, and a dielectric strip 23 is added to the lower concave discontinuous element 25. A dielectric material having a dielectric constant lower than ε ₂ is added.

As described above, the concave discontinuous elements 24 and 25 are provided above and below the dielectric strip 23, and the dielectric constant ε of the dielectric strip 23 is provided on the upper concave discontinuous element 24.
By adding a high dielectric constant epsilon ₁ of the dielectric than _2, the lower side of the concave discontinuity elements 25 for adding the lower dielectric than the dielectric constant epsilon ₂ of the dielectric strip 23, the upper discontinuous elements 24 And a radio wave is radiated from the lower discontinuous element 25 and the reflected wave can be canceled at the same time.

FIG. 4 shows an example of the characteristics of the vertical discontinuous type leak wave NRD guide shown in FIG. 2 of the present invention. Here, the material of the dielectric strip 23 is a = 5.9 mm and b = 5.4 mm.
Teflon band is (ε ₂ = 2.04), the width on the upper side of the dielectric strip 23 0.63 mm, making the discontinuous elements of depth 1.0 mm, wherein the high dielectric constant (epsilon ₁ = 10.2 ) (E.g., Duroid, trade name). The opposite side of the dielectric strip 23 is 2.3 mm wide and d deep.
_Two discontinuous elements are formed. This discontinuous element is hollow and contains only air (ε ₃ = 1.0). Where ε
₁ > ε ₂ > ε ₃ is satisfied, and the experimental frequency is 24
GHz band.

As is clear from the graph of FIG. 4, the radiation amount increases as the depth d ₂ of the discontinuous element increases. The standing wave ratio VSWR is 0.4 d at d = 2 mm.
B (VSWR = 1.05), and the radiation amount at that time is 0.25 dB. Here, radiation amount = input power−mismatch loss.

FIG. 3 shows only the dielectric strip 23 in which the upper metal plate 21 and the lower metal plate 22 have been removed from the upper and lower discontinuous leaky wave NRD guide. Λg intervals.

Next, with reference to FIG. 5, an upper / lower discontinuous type leak wave NRD guide according to a second embodiment of the present invention will be described. FIG. 5 is a sectional view showing the upper metal plate 31 and the lower metal plate 3 for each propagation wavelength λg of the leaky wave NRD guide.
2 in a concave notches 34, 35 each provided as a discontinuous element, the notch 34 of the upper discontinuous elements added to the dielectric permittivity epsilon higher than ₅ permittivity epsilon ₄ of the dielectric strip 33, under Notch 3 as a discontinuous element on the side
5, a dielectric having a dielectric constant ε ₆ lower than the dielectric constant ε ₅ of the dielectric strip 33 is added (ε ₄ > ε ₅ > ε ₆ ).

With this configuration, radio waves can be radiated from the upper discontinuous element 34 and the lower discontinuous element 35, and the reflected waves can be canceled at the same time.

Next, with reference to FIG. 6, a description will be given of a vertically discontinuous leaky wave NRD guide according to a third embodiment of the present invention. FIG. 6 is a sectional view of the dielectric strip 43. As shown in FIG. 6, concave cuts 44 and 45 are provided as discontinuous elements above and below the dielectric strip 43 for each propagation wavelength λg of the leaky wave NRD guide. adding a high dielectric constant epsilon ₇ of the dielectric from the dielectric constant epsilon _8, in the notch 45 are added a dielectric having a low dielectric constant epsilon ₉ than the dielectric constant epsilon ₈ of the dielectric strip 43 (here, epsilon ₇ > ε ₈ > ε ₉
Is). The cuts 44 and 45 formed above and below the dielectric strip 43 are alternately formed at an interval of λg / 2, and the cuts 45 are formed above and below the dielectric strip 43 at positions opposite to the cuts 44. ing.

With such a configuration, it is possible to radiate radio waves from the discontinuous element 44 and the discontinuous element 45 and simultaneously cancel the reflected waves. This is because a small number of discontinuous elements have the same phase every λg / 2. In this state, point wave sources are continuously arranged.

Next, with reference to FIG. 7, a description will be given of a vertically discontinuous leaky wave NRD guide according to a fourth embodiment of the present invention. FIG. 7 is a sectional view showing the upper and lower metal plates 51 and 52 for each propagation wavelength λg of the leaky wave NRD guide.
Cuts 54, 55 as discontinuous elements in each of
The provided, the notch 54 adds a dielectric constant epsilon ₁₁ higher dielectric constant epsilon ₁₀ dielectric of the dielectric strip 53, the notches 55 have a lower dielectric constant epsilon ₁₂ than the dielectric constant epsilon ₁₁ of the dielectric strip 53 A dielectric is added (where ε ₁₁
> Ε ₁₂ > ε ₁₃ ). Then, the upper and lower metal plates 51 and 5
The cuts 54 and 55 formed in 2 are formed alternately at an interval of λg / 2, and the cuts 55 are formed in the upper and lower metal plates 51 and 52 at positions facing the cuts 54.

With such a configuration, it is possible to radiate radio waves from the discontinuous element 54 and the discontinuous element 55 and simultaneously cancel the reflected wave. This is because a small number of discontinuous elements have the same phase every λg / 2. In this state, point wave sources are continuously arranged.

Next, a planar antenna using a vertically discontinuous leaky wave NRD guide according to the present invention will be described with reference to FIG. 8, reference numeral 61 denotes a dielectric strip having the structure shown in FIG. The dielectric strip 61 is sandwiched between two upper and lower metal plates 62 and 63, and the periphery is short-circuited by a metal plate 64.

The upper metal plate 62 is provided with a slot 65 at one wavelength interval of the standing wave. Dielectric strip 6
1 is excited by the coaxial line 66, and the end of the dielectric strip 61 is open.

With this configuration, the leaky wave radiated from the dielectric strip 61 to the broad side propagates through the space below the slot 65 and is reflected by the right end metal wall 64, so that the upper metal plate 62 A standing wave distribution is formed between the lower metal plates 63.

In each slot 65 of the upper metal plate 62, the magnetic field is located at the maximum position at one wavelength interval of the standing wave, so that each slot 65 is excited in the same phase. Since the longitudinal direction of the slot 65 is also in the same phase, linearly polarized waves are radiated in the direction perpendicular to the antenna plane.

Since the radiation and matching are facilitated by each discontinuous element made of a dielectric having a high dielectric constant provided on the dielectric strip of the leaky wave NRD guide, a small antenna or 3d
It can also be used for equipment with strong coupling such as a B-directional coupler.

FIG. FIG. FIG. In the embodiment shown in FIG. 7, a leak wave is generated in a direction perpendicular to the guide. However, the embodiment is not limited as long as the interval between the discontinuous elements is arbitrary. The higher the frequency, the easier the processing can be performed with higher precision by printing or etching.

[0035]

As described above in detail, according to the present invention, it is possible to provide a vertically discontinuous leaky wave NRD guide which can efficiently radiate radio waves even if the structure is simple and short.

[Brief description of the drawings]

FIG. 1 is a sectional view of a basic NRD guide.

FIG. 2 is a cross-sectional view of one block of a vertically discontinuous leaky wave NRD guide according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view of a dielectric strip of the vertically discontinuous leaky wave NRD guide according to the first embodiment of the present invention.

FIG. 4 is a diagram showing a relationship between a depth of a cut provided in the dielectric strip and a radiation amount of a radio wave.

FIG. 5 is a sectional view of a vertically discontinuous leaky wave NRD guide according to a second embodiment of the present invention.

FIG. 6 is a sectional view of a vertically discontinuous leaky wave NRD guide according to a third embodiment of the present invention.

FIG. 7 is a sectional view of a vertically discontinuous leaky wave NRD guide according to a fourth embodiment of the present invention.

FIG. 8 is a perspective view of a planar antenna using a vertically discontinuous leaky wave NRD guide according to the present invention.

[Explanation of symbols]

21, 31, 41, 51 ... upper metal plate, 22, 32, 4
2, 52 ... lower metal plate, 23, 33, 43, 53 ... dielectric strip, 24, 34, 44, 54 ... cut, 2
5, 35, 45, 55 ... cut.

──────────────────────────────────────────────────続 き Continued on the front page (72) Atsushi Minase, Inventor 1406 Hasunuma, Omiya City, Saitama Prefecture Yagi Antenna Co., Ltd. ) Inventor Toshihiko Agatsuma 4-16-20 Tsurugaoka, Izumi-ku, Sendai City, Miyagi Prefecture (56) References JP-A-5-206708 (JP, A) JP40-7848 (JP, B1) JP40-16181 (JP, B1) JP 40-4767 (JP, B1) JP 40-4769 (JP, B1) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01Q 13/00 H01Q 13 / 28 H01P 3/16

Claims (5)

(57) [Claims] 1. A dielectric strip sandwiched between two vertically parallel metal plates or two kinds of discontinuous elements provided inside said metal plate, and one of said discontinuous elements is provided with said dielectric strip. A dielectric having a dielectric constant higher than that of the dielectric strip and a dielectric having a dielectric constant lower than that of the dielectric strip are added to the other discontinuous element. Wave NRD guide. 2. The vertical discontinuous type leaky wave NRD according to claim 1, wherein said two kinds of discontinuous elements are alternately arranged at every λg / 2 in said dielectric strip or metal plate. guide. 3. A concave discontinuous element is provided for each propagation wavelength λg on the upper and lower sides of a dielectric strip sandwiched and disposed between two vertically parallel metal plates. Is characterized by adding a dielectric having a dielectric constant higher than that of the dielectric strip, and adding a dielectric having a dielectric constant lower than that of the dielectric strip to the lower discontinuous element. Upper and lower discontinuous type leak wave NRD guide. 4. Two kinds of concave discontinuous elements are alternately installed at every λg / 2 on the upper and lower sides of a dielectric strip sandwiched between two vertically parallel metal plates. A dielectric having a dielectric constant higher than the dielectric constant of the dielectric strip was added to the discontinuous element, and a dielectric having a dielectric constant lower than the dielectric constant of the dielectric strip was added to the other discontinuous element. Top and bottom discontinuous type leaky wave N
RD guide. 5. A concave cut is provided for each of the propagation wavelengths .lambda.g in the upper and lower metal plates of two vertically parallel metal plates sandwiching the dielectric strip. A dielectric having a dielectric constant higher than that of the dielectric strip, and a dielectric having a dielectric constant lower than that of the dielectric strip is added to the lower metal plate recess. Wave NRD guide.