TWI788156B - Electromagnetic wave transmission structure - Google Patents

Abstract

A electromagnetic wave transmission structure including a substrate, at least one transmission line, a plurality of antennas and a plurality of tunable dielectric units is provided. The transmission line includes a first extending portion and a plurality of second extending portions. The first extending portion extends in a first direction. The second extending portions are arranged along the first direction and respectively extend from two opposite edges of the first extending portion along a second direction. The antennas are disposed near the at least one transmission line. The tunable dielectric units overlap a plurality of portions of the at least one transmission line between the antennas. Each of the tunable dielectric units has a first electrode layer and a controllable dielectric layer overlapped with each other. The controllable dielectric layer is disposed between the first electrode layer and the at least one transmission line.

Description

Electromagnetic wave transmission structure

The present invention relates to an electromagnetic wave transmission structure, and in particular to an electromagnetic wave transmission structure for guiding radio frequency signals or millimeter wave signals.

In the field of mobile communication, how to reduce the energy loss of electromagnetic waves in the transmission path has always been an important issue. As the frequency of electromagnetic waves continues to increase, the energy loss will be more serious when encountering obstacles (such as concrete walls, trees, furniture, signboards, etc.). Therefore, it is easy to generate communication dead spots, dark areas, or areas with weak signals in the application space. Although it can be improved by adding base stations or boosters, the cost of construction, energy consumption, and subsequent hardware maintenance is considerable.

The invention provides an electromagnetic wave transmission structure, which is suitable for improving the energy loss of the electromagnetic wave caused by the obstruction of obstacles, and the receiving and transmitting directions of the electromagnetic wave at the receiving end and the sending end are adjustable.

， 其中k _sspp為經由至少一傳輸線傳遞的電磁波訊號的波數，ε _r為可控介電層的有效介電常數，ω為經由至少一傳輸線傳遞的電磁波訊號的角頻率，c為光速。 The electromagnetic wave transmission structure of the present invention includes a substrate, at least one transmission line, multiple antennas and multiple dielectric adjustable units. At least one transmission line is disposed on the substrate. The transmission line includes a first extension and a plurality of second extensions. The first extension extends in a first direction. The second extensions are respectively extended from two opposite edges of the first extension, and their extension directions are parallel to the second direction. The second extensions are arranged with a pitch P along the first direction, and any two adjacent ones arranged along the first direction have a pitch S. Each second extension has a length L along the second direction. Multiple antennas are disposed on the substrate and adjacent to at least one transmission line. A plurality of dielectrically adjustable units overlap portions of at least one transmission line between the antennas. Each dielectric adjustable unit has an overlapping first electrode layer and a controllable dielectric layer. The controllable dielectric layer is disposed between the first electrode layer and at least one transmission line. The pitch P, spacing S and length L of the transmission line satisfy the following relationship:

, where k _sspp is the wave number of the electromagnetic wave signal transmitted through at least one transmission line, _εr is the effective permittivity of the controllable dielectric layer, ω is the angular frequency of the electromagnetic wave signal transmitted through at least one transmission line, and c is the speed of light.

In an embodiment of the present invention, the transmission line of the above electromagnetic wave transmission structure has a transmission section, a reception section and a transmission section. The transmission segment is connected between the receiving segment and the sending segment. The plurality of dielectrically adjustable units includes a plurality of first dielectrically adjustable units overlapping one of the transmitting segment and the receiving segment. Part of the antenna adjacent to one of the sending section and the receiving section is arranged alternately with the first dielectric adjustable unit along the extending direction of at least one transmission line.

In an embodiment of the present invention, the plurality of dielectrically adjustable units of the electromagnetic wave transmission structure further includes a plurality of second dielectrically adjustable units overlapping the other one of the transmitting section and the receiving section. Another part of the antenna adjacent to the other one of the transmitting section and the receiving section is arranged alternately with the second dielectrically adjustable units along the extending direction.

In an embodiment of the present invention, at least one transmission line of the above-mentioned electromagnetic wave transmission structure is a plurality of transmission lines extending in the first direction. These transmission lines are arranged along the second direction. A plurality of antennas are arranged adjacent to a plurality of receiving sections and a plurality of transmitting sections of the transmission lines respectively. The dielectrically adjustable units further include a plurality of third dielectrically adjustable units overlapping the transmission sections of the transmission lines. These third dielectrically adjustable units are respectively arranged in multiple columns and multiple rows along the first direction and the second direction.

In an embodiment of the present invention, the first electrode layer of each dielectric adjustable unit of the above-mentioned electromagnetic wave transmission structure has a bottom parallel to the substrate and a sidewall extending from the bottom in a bent manner. The sidewall portion surrounds the controllable dielectric layer. The first electrode layer and the at least one transmission line are adapted to generate an electric field for changing the effective permittivity of the controllable dielectric layer.

In an embodiment of the present invention, between the two sidewalls of the two first electrode layers of any two adjacent ones of the plurality of third dielectrically adjustable units arranged along the first direction in the above-mentioned electromagnetic wave transmission structure With insulating layer.

In an embodiment of the present invention, the transmission line of the above electromagnetic wave transmission structure has a transmission section, a reception section and a transmission section. The transmission segment is connected between the receiving segment and the sending segment. The at least one transmission line is a plurality of transmission lines extending in the first direction. These transmission lines are arranged along the second direction. A plurality of antennas are arranged adjacent to a plurality of receiving sections and a plurality of transmitting sections of the transmission lines respectively. At least a part of the plurality of dielectric adjustable units overlaps the plurality of transmission sections of the transmission lines, and is arranged in multiple columns and rows along the first direction and the second direction respectively.

In an embodiment of the present invention, the first electrode layer of each dielectric adjustable unit of the above-mentioned electromagnetic wave transmission structure has a bottom parallel to the substrate and a sidewall extending from the bottom in a bent manner. The sidewall portion surrounds the controllable dielectric layer. The first electrode layer and the at least one transmission line are adapted to generate an electric field for changing the effective permittivity of the controllable dielectric layer.

In an embodiment of the present invention, at least one transmission line of the above-mentioned electromagnetic wave transmission structure is one transmission line. Each of the plurality of antennas is at the same distance from the transmission line. These antennas are arranged along the extension direction of the transmission line and have an axis of symmetry. The diameter of each antenna either decreases or increases away from the axis of symmetry.

In an embodiment of the present invention, at least one transmission line of the above-mentioned electromagnetic wave transmission structure is one transmission line. The respective geometric centers of the plurality of antennas are at the same distance from the transmission line. These antennas are arranged along the extension direction of the transmission line and have an axis of symmetry. The diameter of each antenna either decreases or increases away from the axis of symmetry.

In an embodiment of the present invention, at least one transmission line of the above-mentioned electromagnetic wave transmission structure is one transmission line. Each of the plurality of antennas has the same diameter. These antennas are arranged along the extension direction of the transmission line and have an axis of symmetry. The spacing of each antenna from the transmission line increases with distance from the axis of symmetry.

In an embodiment of the present invention, each dielectric adjustable unit of the above-mentioned electromagnetic wave transmission structure further includes a second electrode layer disposed on the surface of the substrate facing away from at least one transmission line and overlapping the controllable dielectric layer. The first electrode layer and the second electrode layer are suitable for generating an electric field for changing the effective dielectric constant of the controllable dielectric layer.

In an embodiment of the present invention, the controllable dielectric layer of the above electromagnetic wave transmission structure is a liquid crystal layer.

In an embodiment of the present invention, the first electrode layer of the above-mentioned electromagnetic wave transmission structure includes a plurality of first strip electrodes and a plurality of second strip electrodes. The first strip electrodes and the second strip electrodes are alternately arranged along a first direction and parallel to the plurality of second extensions. Any adjacent one of the first strip electrodes and one of the second strip electrodes is suitable for generating an electric field for changing the effective permittivity of the controllable dielectric layer.

Based on the above, in an electromagnetic wave transmission structure according to an embodiment of the present invention, a plurality of antennas are disposed adjacent to the transmission line, and a plurality of dielectric adjustable units are disposed in portions of the transmission line between the antennas. By electrically controlling and modulating the effective permittivity of the controllable dielectric layer overlapping the transmission line in the dielectric tunable unit, the phase of the electromagnetic wave signal can be changed, thereby modulating the direction of the electromagnetic wave sending and receiving of these antennas.

As used herein, "about," "approximately," "essentially," or "essentially" includes the stated value and averages within acceptable deviations from the particular value as determined by one of ordinary skill in the art, taking into account the The measurement in question and the specific amount of error associated with the measurement (ie, the limitations of the measurement system). For example, "about" can mean within one or more standard deviations of the stated value, or for example within ±30%, ±20%, ±15%, ±10%, ±5%. Furthermore, "about", "approximately", "essentially" or "substantially" used herein can choose a more acceptable deviation range or standard deviation according to the nature of measurement, cutting or other properties, and can be Not one standard deviation applies to all properties.

In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "connected to" another element, it can be directly on or connected to the other element, or Intermediate elements may also be present. In contrast, when an element is referred to as being "directly on" or "directly connected to" another element, there are no intervening elements present. As used herein, "connected" may refer to physical and/or electrical connection. Furthermore, "electrically connected" may mean that other elements exist between two elements.

Reference will now be made in detail to the exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and descriptions to refer to the same or like parts.

FIG. 1 is a schematic top view of an electromagnetic wave transmission structure according to a first embodiment of the present invention. FIG. 2A is an enlarged schematic view of a local area of the electromagnetic wave transmission structure in FIG. 1 . FIG. 2B is a schematic top view of another modified embodiment of the transmission line in FIG. 2A . 3A and 3B are schematic cross-sectional views of the dielectric tunable unit in FIG. 2A operating in different states. 4A to 4C are schematic top views of other modified embodiments of the electromagnetic wave transmission structure in FIG. 1 . 3A and 3B correspond to the section line A-A' of FIG. 2A.

Referring to FIG. 1 and FIG. 2 , the electromagnetic wave transmission structure 10 includes a substrate 100 , a transmission line 120 and a plurality of antennas 140 disposed on the substrate 100 . The substrate 100 is, for example, a glass substrate, a ceramic laminate, or a low dielectric loss substrate (such as a Rogers substrate), but not limited thereto. In this embodiment, the transmission line 120 includes a first extension portion 120P1 and a plurality of second extension portions 120P2 , and the second extension portions 120P2 respectively extend from two opposite edges e1 and e2 of the first extension portion 120P1 .

For example, the first extension portion 120P1 and the second extension portion 120P2 may extend in a direction X and a direction Y respectively, and the direction X may be selectively perpendicular to the direction Y, but not limited thereto. In this embodiment, the orthographic profile of the second extension portion 120P2 on the substrate 100 may be a rectangle. That is, the second extending portion 120P2 is arranged in the direction X and the extending directions of the two opposite edges are parallel to each other and parallel to the direction Y, but not limited thereto. In other embodiments, the orthographic profile of the second extension portion 120P2-A of the transmission line 120A on the substrate 100 may also be trapezoidal (the electromagnetic wave transmission structure 10A shown in FIG. 2B ). More specifically, the extending direction of the two opposite edges of the second extending portion 120P2-A arranged in the direction X may not be parallel to the direction Y, that is, not perpendicular to the two edges e1, e2 of the first extending portion 120P1.

In this embodiment, the electromagnetic wave transmission structure 10 has a receiving area RA, a transmitting area TA, and a transmitting area EA, and is suitable for being installed on obstacles that easily cause energy loss of electromagnetic waves (such as concrete walls or building pillars). For example, an obstacle (not shown) has a front facing the electromagnetic wave source and a back facing away from the electromagnetic wave source. The electromagnetic wave transmission structure 10 may be disposed on the obstacle and detour from the front of the obstacle to the back of the obstacle. Wherein, the receiving area RA and the transmitting area EA of the electromagnetic wave transmission structure 10 are respectively arranged on the front and back of the obstacle, and the transmission area TA can extend on other planes connecting the front and back of the obstacle.

The transmission line 120 can be divided into a receiving section 120rs extending in the receiving area RA, a transmitting section 120ts extending in the transmitting area TA, and a sending section 120es extending in the sending area EA, wherein the transmitting section 120ts is connected between the receiving section 120rs and the sending section Between 120es. In this embodiment, the antenna 140 is, for example, a patch antenna. A part of the antennas 140 can be disposed in the receiving area RA as the receiving antenna 140R, and another part of the antennas 140 can be disposed in the transmitting area EA as the transmitting antenna 140E. For example, the electromagnetic waves transmitted towards the front of the obstacle can be fed into the transmission line 120 via the receiving antenna 140R in the receiving area RA of the electromagnetic wave transmission structure 10, and then enter the transmission line 120 located on the back of the obstacle through transmission through the transmission section 120ts of the transmission line 120. District EA. Through the coupling effect between the transmitting section 120es of the transmission line 120 and the transmitting antenna 140E, the electromagnetic wave signal transmitted to the transmitting area EA can be radiated through the transmitting antenna 140E.

That is to say, when there is an obstacle that consumes the energy of the electromagnetic wave in the transmission space of the electromagnetic wave, the electromagnetic wave transmission structure 10 of this embodiment can be installed on the obstacle as a detour structure for the electromagnetic wave, thereby reducing the passage of the electromagnetic wave. The energy loss caused by this obstacle.

Further, the plurality of receiving antennas 140R located in the receiving area RA may be adjacent to one side of the receiving section 120rs of the transmission line 120, and arranged in a line along the extension direction (for example, the direction X) of the first extension portion 120P1 of the transmission line 120. dimensional receiving antenna array. Similarly, the multiple transmitting antennas 140E located in the transmitting area EA are adjacent to one side of the transmitting section 120es of the transmission line 120 and arranged along the extending direction of the first extension 120P1 of the transmission line 120 to form a one-dimensional transmitting antenna array. Although the receiving antenna 140R and the transmitting antenna 140E shown in FIG. 1 are located on the same side of the transmission line 120 , the present invention is not limited thereto. In other embodiments, the receiving antenna 140R and the transmitting antenna 140E may also be disposed on opposite sides of the transmission line 120 respectively, or the receiving antenna 140R (or the transmitting antenna 140E) is adjacent to the opposite sides of the transmission line 120 .

In order to adjust the transmitting and receiving directions of the electromagnetic waves of the plurality of antennas 140 , the electromagnetic wave transmission structure 10 further includes a plurality of dielectric adjustable units 160 . It is particularly noted that the dielectrically tunable units 160 overlap the transmission line 120 along a direction (eg, direction Z) perpendicular to the substrate 100 . In this embodiment, these dielectrically adjustable units 160 can be respectively arranged in the sending area EA and the receiving area RA. A dielectric adjustable unit 162.

These dielectrically adjustable units 161 respectively overlap a plurality of parts (or sections) of the transmission section 120es of the transmission line 120 between the plurality of transmission antennas 140E along the direction Z. Similarly, the dielectrically adjustable units 162 respectively overlap multiple parts (or sections) of the receiving section 120rs of the transmission line 120 between the receiving antennas 140R along the direction Z. That is to say, the transmitting antenna 140E adjacent to the transmitting section 120es and the dielectrically adjustable units 161 are alternately arranged along the extension direction of the transmission line 120 (for example, the direction X), while the receiving antenna 140R adjacent to the receiving section 120rs is arranged with the The dielectrically adjustable units 162 are arranged alternately along the extending direction of the transmission line 120 .

Please refer to FIG. 3A and FIG. 3B at the same time. In this embodiment, the dielectric adjustable unit 160 has the first electrode layer EL1 and the controllable dielectric layer CDL overlapping in the direction Z, and the controllable dielectric layer CDL is set between the first electrode layer EL1 and the transmission line 120 . The controllable dielectric layer CDL is, for example, a liquid crystal layer, and the electric field generated by the potential difference between the first electrode layer EL1 and the transmission line 120 is suitable for driving a plurality of liquid crystal molecules LCM of the liquid crystal layer to rotate. For example, the first electrode layer EL1 may be disposed on another substrate SUB, and a spacer SP is interposed between the substrate SUB and the substrate 100 to form an accommodating space for the controllable dielectric layer CDL.

， 其中k _sspp為經由傳輸線120傳遞的電磁波訊號的波數（wavenumber），ε _r為可控介電層CDL的有效介電常數，ω為經由傳輸線傳遞的電磁波訊號的角頻率（angular frequency），c為光速。 Further, the plurality of second extensions 120P2 of the transmission line 120 are arranged at opposite sides of the first extension 120P1 along the direction X with a pitch P. Any two adjacent ones of the second extending portions 120P2 arranged along the direction X have a distance S, and each of them has a length L along the direction Y. In particular, the structural dimensions of the transmission line 120 satisfy the following relationship:

, where k _sspp is the wave number (wavenumber) of the electromagnetic wave signal transmitted through the transmission line 120, _εr is the effective permittivity of the controllable dielectric layer CDL, ω is the angular frequency (angular frequency) of the electromagnetic wave signal transmitted through the transmission line, c is the speed of light.

Since the liquid crystal material used as the controllable dielectric layer CDL in this embodiment has dielectric anisotropy (dielectric anisotropy), that is, the liquid crystal material has different dielectric constants in directions parallel to and perpendicular to the long axis of the liquid crystal molecules ( For example: permittivity ε _// and permittivity ε _┴ ), making it electrically controllable. In other words, by applying an electric field to the liquid crystal layer, the effective dielectric constant (effective dielectric constant) of the liquid crystal layer in a specific direction can be changed, and the effective dielectric constant will fall between the dielectric constant ε _// and the dielectric constant ε _┴ range between.

For example, in this embodiment, the controllable dielectric layer CDL can use liquid crystal material K15 (Merck KGaA) with a dielectric constant ε _// and a dielectric constant ε _┴ of 2.9 and 2.72, respectively, and a horizontal alignment capability Alignment material layer (for example: polyimide film after brushing with fluff) to align liquid crystal molecules LCM. Wherein, the alignment material layer may be disposed at the junction of the liquid crystal layer and the first electrode layer EL1 and/or the junction of the liquid crystal layer and the substrate 100 . However, the present invention is not limited thereto. In other embodiments, the selection of liquid crystal materials and their alignment methods can be adjusted according to different application requirements.

In this embodiment, when the liquid crystal layer is in a state where no electric field is applied, its liquid crystal molecules LCM are arranged parallel to the substrate 100 (as shown in FIG. 3A ). At this time, the effective dielectric constant of the controllable dielectric layer CDL to the electromagnetic wave signal transmitted on the transmission line 120 is a relatively large dielectric constant ε _// , so that the equivalent electromagnetic wave has a smaller wavelength and a larger wave number, so the corresponding Compared with the state of applying an electric field described later, the controllable dielectric layer CDL without an electric field can generate more phase shift (phase shift) in the X-axis direction.

When the liquid crystal layer is applied with an electric field, that is, when there is a potential difference between the first electrode layer EL1 and the transmission line 120, the liquid crystal material K15 has a relatively large dielectric constant in the direction of the molecular long axis, and its molecular long axis tends to be along the The direction of the electric field is aligned. In this embodiment, the direction of the electric field formed in the overlapped area of the first electrode layer EL1 and the transmission line 120 is substantially perpendicular to the substrate 100 . When the electric field strength is strong enough, the major axes of most liquid crystal molecules located in the overlapping region will be substantially perpendicular to the substrate 100 (as shown in FIG. 3B ). At this time, the effective permittivity of the controllable dielectric layer CDL to the electromagnetic wave signal transmitted on the transmission line 120 is a relatively small permittivity ε _┴ . When an electric field is applied to the dielectric control layer CDL), less phase shift can be generated in the X-axis direction.

Therefore, by changing the alignment direction of the liquid crystal molecules LCM with or without an applied electric field or with different magnitudes of the applied electric field, the effective permittivity of the controllable dielectric layer CDL in the direction of the electric field of the electromagnetic wave signal can be changed, thereby changing the transmission line 120 The phase of the transmitted electromagnetic wave signal.

In this embodiment, the receiving section 120rs and the transmitting section 120es of the transmission line 120 are provided with a dielectric adjustable unit 160 between any two adjacent antennas 140, and the phase adjustment by the dielectric adjustable unit 160 The variable capability can change the electromagnetic wave transmitting and receiving direction of the multiple antennas 140 of the one-dimensional antenna array arranged along one side of the transmission line 120, wherein the adjustment of the electromagnetic wave transmitting and receiving direction is, for example, in the dimension of the XZ plane.

For example, the plurality of dielectric adjustable units 161 located in the transmission area EA is suitable for adjusting the phase of the electromagnetic wave signal transmitted in the transmission section 120es of the transmission line 120 . Therefore, the electromagnetic wave signals coupled and radiated from the transmission line 120 by the multiple transmitting antennas 140E have different phase combinations according to the phase shift given by each dielectric adjustable unit 161, so as to change the transmission of the electromagnetic wave on the XZ plane. direction. On the other hand, when the electromagnetic waves are received by the receiving antenna 140R and fed into the receiving section 120rs of the transmission line 120, the plurality of dielectric adjustable units 162 located in the receiving area RA are adapted to adjust the electromagnetic wave signals fed into the transmission line 120 at different delay times. Equivalently speaking, the receiving field pattern of the receiving section 120rs on the XZ plane is adjusted.

Furthermore, the orthographic profile of the antenna 140 in this embodiment on the substrate 100 is, for example, a circle, and the size (eg, diameter) of each antenna 140 is substantially the same. In this embodiment, the distance s1 between each antenna 140 and the adjacent transmission line 120 is also substantially the same. Therefore, the degree of energy coupling between each antenna 140 and the transmission line 120 is similar. For example, the energy difference of the electromagnetic wave fed into the transmission line 120 through each receiving antenna 140R is not large, and the power of the electromagnetic wave signal radiated through each transmitting antenna 140E is also similar, so that the electromagnetic wave radiated by the transmitting antenna array has a main beam (main beam) The beam width (beam width/half power beam width, HPBW) of the lobe) will be narrower, and the radiation power difference between the side lobe and the main beam will be smaller.

However, the present invention is not limited thereto. In other modified embodiments, the multiple antennas constituting the antenna array may also have different sizes, and the distances between these antennas and the transmission line may also be different. Referring to FIG. 4A , in a variant embodiment, the multiple antennas 140A (such as the receiving antenna 140R-A and the transmitting antenna 140E-A) of the electromagnetic wave transmission structure 10B may have different sizes. In detail, the plurality of receiving antennas 140R-A have a symmetry axis SA, and the respective diameters (or circular diameters) of the receiving antennas 140R-A increase as the distance from the symmetry axis SA increases. Multiple transmit antennas 140E-A are also configured in the same manner.

For example, the antenna 140A located on the axis of symmetry SA has the best reception/radiation efficiency for electromagnetic waves of a specific frequency (that is, the resonant frequency of the central antenna is the carrier frequency of the pre-transmitting signal), while the antenna 140A positioned away from the axis of symmetry SA Moreover, the receiving/radiating efficiency of the antenna 140A with different sizes for the electromagnetic wave of the specific frequency will decrease as the size (eg diameter) of the antenna increases. Through such a configuration, the beam width of the main beam of the electromagnetic waves radiated by the transmitting antenna array can be widened, and the radiation power of the side beams can be suppressed.

In order to achieve a similar effect, in another modified embodiment shown in FIG. 4B , the size configuration of the multiple antennas 140B (such as the receiving antenna 140R-B and the transmitting antenna 140E-B) of the electromagnetic wave transmission structure 10C is similar to that of FIG. 4A There are a plurality of antennas 140A, but the spacing between these antennas 140B and adjacent transmission lines 120 may be different. It is particularly noted that the distances d between the respective geometric centers C of these antennas 140B and the adjacent transmission lines 120 are substantially the same.

Different from the embodiment in FIG. 4B , in the electromagnetic wave transmission structure 10D shown in FIG. 4C , the respective diameters of the plurality of receiving antennas 140R-C decrease gradually as they move away from the axis of symmetry SA, and the diameters of the plurality of transmitting antennas 140E-C also use the same way to configure. In addition, the resonant frequency of the central antenna (the receiving antenna 140R-C and the transmitting antenna 140E-C disposed on the axis of symmetry SA) is the carrier frequency of the pre-transmitting signal. However, the present invention is not limited thereto. In an embodiment, the configurations of the transmitting antenna array and the receiving antenna array may also be selectively different.

Some other embodiments will be listed below to describe the present disclosure in detail, wherein the same components will be marked with the same symbols, and the description of the same technical content will be omitted.

FIG. 5 is a schematic top view of an electromagnetic wave transmission structure according to a second embodiment of the present invention. Please refer to FIG. 5 , the difference between the electromagnetic wave transmission structure 10E of this embodiment and the electromagnetic wave transmission structure 10 of FIG. 1 lies in that the configuration of the antenna array is different. In this embodiment, the antenna array formed by the plurality of antennas 140D of the electromagnetic wave transmission structure 10E has a symmetry axis SA, and the distance s2 between each of the plurality of antennas 140D of the antenna array and the transmission line 120 increases as the distance from the symmetry axis SA increases. In other words, the distance between the antenna 140D (eg, the receiving antenna 140R-D and the transmitting antenna 140E-D) on the axis of symmetry SA and the transmission line 120 is the smallest, and thus its energy coupling degree is the largest. Conversely, the distance between the antenna 140D located outside the antenna array and the transmission line 120 is the largest, so its energy coupling degree is the smallest.

Therefore, the antenna 140D positioned on the axis of symmetry SA has the best receiving/radiating efficiency for electromagnetic waves of a specific frequency, while the receiving/radiating efficiency of the antenna 140D disposed away from the axis of symmetry SA and having the same size for electromagnetic waves of a specific frequency will vary with The distance s2 between the antenna 140D and the transmission line 120 increases and decreases. For example, through such a configuration, the beam width of the main beam of the electromagnetic waves radiated by the transmitting antenna array can be widened, and the radiation power of the side beams can be suppressed.

FIG. 6 is a schematic top view of an electromagnetic wave transmission structure according to a third embodiment of the present invention. Fig. 7 is a schematic cross-sectional view of the electromagnetic wave transmission structure in Fig. 6 along the section line B-B'. For clarity, FIG. 6 omits the illustration of the substrate SUB, the controllable dielectric layer CDL and the spacer SP in FIG. 7 . Please refer to FIG. 6 and FIG. 7. Compared with the electromagnetic wave transmission structure 10 in FIG. On one side of the surface 100s and along the direction Z overlaps the controllable dielectric layer CDL.

It should be noted that, different from the electromagnetic wave transmission structure 10 of the previous embodiment, the first electrode layer EL1 and the second electrode layer EL2 of the dielectric tunable unit 160A of this embodiment are suitable for producing a controllable dielectric layer CDL The electric field of the effective permittivity. That is to say, in this embodiment, the transmission line 120 is not used as an electrode for driving the controllable dielectric layer CDL.

On the other hand, in this embodiment, the second electrode layer EL2 and the first electrode layer EL1 are patterned electrodes, but not limited thereto. In a preferred embodiment, the second electrode layer EL2 may also be a monolithic electrode corresponding to the plurality of first electrode layers EL1 of the plurality of dielectric adjustable units 160A. That is, the second electrode layer EL2 may be a non-patterned electrode layer covering the entire surface 100s of the substrate 100 .

FIG. 8 is a schematic top view of an electromagnetic wave transmission structure according to a fourth embodiment of the present invention. FIG. 9 is an enlarged schematic view of a partial area of the electromagnetic wave transmission structure in FIG. 8 . Fig. 10 is a schematic cross-sectional view of the electromagnetic wave transmission structure in Fig. 8 along the section line C-C'. Fig. 11 is a schematic cross-sectional view of the electromagnetic wave transmission structure in Fig. 9 along the section line D-D'.

Referring to FIGS. 8 to 11 , in this embodiment, the electromagnetic wave transmission structure 30 may include multiple transmission lines, such as a transmission line 121 , a transmission line 122 , a transmission line 123 and a transmission line 124 . Since the configuration relationship and corresponding technical effects of each transmission line 120, antenna 140, dielectric adjustable unit 161, and dielectric adjustable unit 162 in this embodiment are similar to the electromagnetic wave transmission structure 10 in Figure 1, please refer to Refer to relevant paragraphs of the aforementioned embodiments, and details are not repeated here.

In this embodiment, the multiple antennas 140 adjacent to the multiple transmission lines 120 can be arranged in multiple columns and multiple rows along the direction X and the direction Y respectively. For example, a plurality of receiving antennas 140R located in the receiving area RA can be arranged to form a two-dimensional receiving antenna array, and a plurality of transmitting antennas 140E located in the transmitting area EA can be arranged to form a two-dimensional transmitting antenna array. . However, the present invention is not limited thereto. In another unillustrated embodiment, the plurality of antennas 140 located in the receiving area RA or the transmitting area EA can also be arranged in a honeycomb-shaped two-dimensional antenna array. For example, any two adjacent ones of the plurality of one-dimensional antenna arrays arranged along the direction X may be misaligned in the direction Y.

It should be noted that, in addition to the dielectric adjustable units 160B in the receiving area RA and the transmitting area EA, the electromagnetic wave transmission structure 30 of this embodiment also has a plurality of dielectric adjustable units 163 in the transmission area TA. The dielectrically adjustable units 163 overlap the transmission segments 120 ts of the transmission lines 120 along the direction Z, and are arranged in columns and rows along the directions X and Y, respectively. That is, the dielectrically adjustable units 163 can be arranged in an array in the transmission area TA of the electromagnetic wave transmission structure 30 . Since the detailed composition of the dielectric tunable unit 163 is similar to that of the dielectric tunable unit 161 and the dielectric tunable unit 162 , it will not be repeated here.

In this embodiment, a plurality of dielectric adjustable units 163 located in the transmission area TA and overlapping the same transmission line 120 are adjacently arranged. More specifically, there is no gap between the dielectrically adjustable units 163 arranged along the transmission section 120ts. Therefore, the energy attenuation caused by the discontinuity of the surrounding dielectric layer when the electromagnetic wave signal is transmitted on the transmission line 120 can be avoided. On the other hand, when multiple dielectrically adjustable units 163 on the same transmission line 120 are driven, the effective dielectric constants of their respective controllable dielectric layers CDL (as shown in Figure 11 ) can be transferred from the receiving section 120rs to the transmitting section 120es direction gradient, for example: gradually increase, gradually decrease, decrease first and then increase or increase first and then decrease. That is to say, the dielectric constant difference between any two adjacent ones of the plurality of controllable dielectric layers CDL of the dielectric adjustable units 163 will not be too large, so as to avoid obvious energy loss when the electromagnetic wave signal passes through.

For example, different voltages can be applied to the first electrode layers EL1-A of these dielectrically adjustable units 163 on the same transmission line 120, so that the liquid crystal molecules of the liquid crystal layer as the controllable dielectric layer CDL The degree of rotation is different, and the effective _permittivity in the direction of the electric field of the electromagnetic wave signal produces an approximately continuous change. Electrical constant ε _// Between. It should be noted that the approximate continuous change of the effective dielectric constant here means that any two adjacent dielectric tunable units 163 have very little difference in effective permittivity, and this difference can depend on the same transmission line The number of dielectrically adjustable units 163 on 120. That is to say, if the number of dielectric tunable units 163 on the same transmission line 120 is more, the variation of the effective dielectric constant on the transmission line 120 will be closer to a continuous variation.

It is particularly noted that these dielectric adjustable units 163 arranged on different transmission lines 120 can be used to adjust the phase difference between electromagnetic wave signals transmitted on different transmission lines 120, so that the two-dimensional antenna array of this embodiment has both XZ The ability to adjust the direction of electromagnetic wave transmission and reception on the plane and YZ plane.

For example, these dielectric adjustable units 163 are suitable for adjusting the phases of the multiple electromagnetic wave signals transmitted in the multiple transmission sections 120ts of the transmission lines 120, so that these electromagnetic wave signals are respectively transmitted to the transmission area EA with different delay times. Radiated via the corresponding plurality of transmit antennas 140E. At this time, if the plurality of dielectric adjustable units 161 in the transmitting area EA are not activated, the transmitting direction of the electromagnetic wave can be modulated on the YZ plane. On the contrary, if these dielectrically adjustable units 161 are activated at the same time, the sending direction of the electromagnetic wave can be modulated on the YZ plane and the XZ plane at the same time.

Please refer to FIG. 10 and FIG. 11 at the same time. In this embodiment, the first electrode layer EL1-A of the dielectric tunable unit 160B has a bottom EL1bp parallel to the substrate 100 and a sidewall EL1sp bently extending from the bottom EL1bp. Wherein the sidewall portion EL1sp surrounds the controllable dielectric layer CDL. More specifically, the controllable dielectric layer CDL of each dielectric adjustable unit 160B in this embodiment is covered by the first electrode layer EL1-A. Therefore, it can be ensured that the driving of the controllable dielectric layer CDL of each dielectric tunable unit 160B will not be affected by the electrodes of another dielectric tunable unit 160B.

However, the present invention is not limited thereto. In another modified embodiment, each of the plurality of first electrode layers of the plurality of dielectric adjustable units may have at least one gap, and the gap between the first electrode layer and the substrate 100 is used to fill the liquid crystal layer (that is, the controllable dielectric layer CDL). The accommodating spaces can be communicated through the at least one gap. In other words, in this variant embodiment, the first electrode layers of the dielectrically adjustable units can be arranged in a continuous liquid crystal layer.

Further, in this embodiment, the electromagnetic wave transmission structure 30 may further include an insulating layer INS1 and an insulating layer INS2 . An insulating layer INS1 is disposed between the first electrode layer EL1 -A and the transmission line 120 to electrically isolate each other. An insulating layer INS2 is disposed between any two adjacent first electrode layers EL1-A to electrically isolate each other. On the other hand, since the distance between the two adjacent first electrode layers EL1-A on the two transmission lines 120 in this embodiment is relatively long, the two adjacent first electrodes arranged along the direction Y The insulating layer INS2 may not be provided between the layers EL1-A, but not limited thereto. In other embodiments, the insulating layer INS2 may also be disposed around the first electrode layer of each dielectric adjustable unit to insulate the first electrode layer of another dielectric adjustable unit arranged in different directions and adjacent to each other.

FIG. 12 is a schematic top view of the electromagnetic wave transmission structure of the fifth embodiment of the present invention. 13A and 13B are schematic cross-sectional views of the dielectric tunable unit of FIG. 12 operating in different states. 13A and 13B correspond to the line E-E' in FIG. 12 . For the sake of clarity, FIG. 12 omits the illustration of the substrate SUB, the controllable dielectric layer CDL and the spacer SP in FIG. 13A and FIG. 13B . Please refer to FIG. 12 to FIG. 13B , the difference between the electromagnetic wave transmission structure 10F of this embodiment and the electromagnetic wave transmission structure 10 of FIG. 3A lies in the configuration of the first electrode layer of the dielectric adjustable unit and the driving method of the liquid crystal layer.

Specifically, in this embodiment, the first electrode layer EL1-B of the dielectric adjustable unit 160C includes a plurality of first strip electrodes SE1 and a plurality of second strip electrodes SE2. The first strip-shaped electrodes SE1 and the second strip-shaped electrodes SE2 are alternately arranged along the extending direction (eg, direction X) of the first extending portion 120P1 of the transmission line 120 , and are parallel to the second extending portion 120P2 . In this embodiment, the transmission line 120 is not used as an electrode for driving the controllable dielectric layer CDL, but uses the electric field generated between any adjacent first strip-shaped electrode SE1 and a second strip-shaped electrode SE2 to change The effective dielectric constant of the controllable dielectric layer CDL.

For example, in this embodiment, when the plurality of liquid crystal molecules LCM of the liquid crystal layer serving as the controllable dielectric layer CDL are not applied with an electric field, their alignment directions (ie, alignment directions) are substantially parallel to the second extending The extension direction of the portion 120P2 (as shown in FIG. 13A ). When the first electrode layer EL1 -B is activated, a transverse electric field substantially parallel to the substrate 100 is formed between the first strip electrode SE1 and the second strip electrode SE2 . Since the liquid crystal material used in this embodiment is a positive type liquid crystal material (that is, the dielectric constant ε _// of the liquid crystal molecule LCM in the direction of the long axis is greater than the dielectric constant ε _┴ in the direction of the short axis), the liquid crystal molecule LCM The long axes will tend to align along the direction of this transverse electric field (as shown in Figure 13B). More specifically, the liquid crystal layer of this embodiment operates in an in-plane switching (IPS) mode.

Different from the dielectric tunable unit 160 in FIG. 3A and FIG. 3B , when the dielectric tunable unit 160C of this embodiment is not activated, the effective permittivity of the controllable dielectric layer CDL in the direction of the electric field of the electromagnetic wave signal For the smaller dielectric constant ε _┴ , so less phase shift can be produced. On the contrary, when the dielectric tunable unit 160C is enabled, the effective dielectric constant of the controllable dielectric layer CDL in the direction of the electric field of the electromagnetic wave signal is a relatively large dielectric constant ε _// , so it can generate more phase shift.

FIG. 14 is a schematic top view of the electromagnetic wave transmission structure of the sixth embodiment of the present invention. Please refer to FIG. 14 , different from the electromagnetic wave transmission structure 10 in FIG. 1 , the multiple dielectric adjustable units 160D of the electromagnetic wave transmission structure 10G in this embodiment, for example: multiple dielectric adjustable units 161D located in the transmission area EA Or/and a plurality of dielectric adjustable units 162D located in the receiving area RA are adjacently arranged. For example, for the dielectrically adjustable unit 160D between two adjacent antennas 140, its borders on opposite sides in the arrangement direction of the two antennas 140 can be respectively aligned with the respective geometric centers C of the two antennas 140. .

That is to say, there is no gap between the plurality of dielectric adjustable units 160D in the receiving area RA or the transmitting area EA. Therefore, energy attenuation due to the discontinuity of the surrounding dielectric layer can be avoided when the electromagnetic wave signal is transmitted on the receiving section 120rs or the transmitting section 120es of the transmission line 120 .

To sum up, in an electromagnetic wave transmission structure according to an embodiment of the present invention, a plurality of antennas are arranged adjacent to the transmission line, and a plurality of dielectric adjustable units are arranged in parts of the transmission line between the antennas. By electrically controlling and modulating the effective permittivity of the controllable dielectric layer overlapping the transmission line in the dielectric tunable unit, the phase of the electromagnetic wave signal can be changed, thereby modulating the direction of the electromagnetic wave sending and receiving of these antennas.

10, 10A, 10B, 10C, 10D, 10E, 10F, 10G, 20, 30: Electromagnetic wave transmission structure 100. SUB: Substrate 120, 120A, 121, 122, 123, 124: transmission line 120P1: first extension F 120P2, 120P2-A: second extension 120es: send segment 120rs: receiving segment 120ts: transmission segment 140, 140A, 140B, 140D: Antenna 140E, 140E-A, 140E-B, 140E-C, 140E-D: transmitting antenna 140R, 140R-A, 140R-B, 140R-C, 140R-D: receiving antenna 160, 161, 162, 163, 160A, 160B, 160C, 160D, 161D, 162D: dielectric adjustable unit C: geometric center CDL: Controlled Dielectric Layer d: distance e1, e2: edges EA: sending area EL1, EL1-A, EL1-B: first electrode layer EL1bp: bottom EL1sp: side wall EL2: second electrode layer INS1, INS2: insulating layer L: Length LCM: liquid crystal molecule P: Pitch RA: receiving area S, s1, s2: Spacing SA: axis of symmetry SE1: the first strip electrode SE2: Second strip electrode SP: spacer TA: transfer area X, Y, Z: direction A-A', B-B', C-C', D-D', E-E': broken line

FIG. 1 is a schematic top view of an electromagnetic wave transmission structure according to a first embodiment of the present invention. FIG. 2A is an enlarged schematic view of a local area of the electromagnetic wave transmission structure in FIG. 1 . FIG. 2B is a schematic top view of another modified embodiment of the transmission line in FIG. 2A . 3A and 3B are schematic cross-sectional views of the dielectric tunable unit in FIG. 2A operating in different states. 4A to 4C are schematic top views of other modified embodiments of the electromagnetic wave transmission structure in FIG. 1 . FIG. 5 is a schematic top view of an electromagnetic wave transmission structure according to a second embodiment of the present invention. FIG. 6 is a schematic top view of an electromagnetic wave transmission structure according to a third embodiment of the present invention. FIG. 7 is a schematic cross-sectional view of the electromagnetic wave transmission structure in FIG. 6 . FIG. 8 is a schematic top view of an electromagnetic wave transmission structure according to a fourth embodiment of the present invention. FIG. 9 is an enlarged schematic view of a partial area of the electromagnetic wave transmission structure in FIG. 8 . FIG. 10 is a schematic cross-sectional view of the electromagnetic wave transmission structure of FIG. 8 . FIG. 11 is a schematic cross-sectional view of the electromagnetic wave transmission structure of FIG. 9 . FIG. 12 is a schematic top view of the electromagnetic wave transmission structure of the fifth embodiment of the present invention. 13A and 13B are schematic cross-sectional views of the dielectric tunable unit of FIG. 12 operating in different states. FIG. 14 is a schematic top view of the electromagnetic wave transmission structure of the sixth embodiment of the present invention.

10: Electromagnetic wave transmission structure

100: Substrate

120: transmission line

120P1: first extension

120P2: Second extension

140: Antenna

160:dielectric adjustable unit

e1, e2: edges

L: Length

P: Pitch

S: Spacing

X, Y, Z: direction

A-A': section line

Claims (14)

An electromagnetic wave transmission structure, comprising: a substrate; at least one transmission line disposed on the substrate, each of the at least one transmission line comprising: a first extension extending in a first direction; and a plurality of second extensions, respectively extend from opposite two edges of the first extension portion, the extension direction of the second extension portions is parallel to a second direction, the second extension portions are arranged at a pitch P along the first direction, and the first extension portions are arranged at a pitch P along the first direction. Any two adjacent ones of the two extensions arranged along the first direction have a distance S, and each of the second extensions has a length L along the second direction; a plurality of antennas are arranged on the substrate, and adjacent to the at least one transmission line; and a plurality of dielectrically adjustable units overlapping a plurality of parts of the at least one transmission line between the antennas, and each of the dielectrically adjustable units has a first overlapped An electrode layer and a controllable dielectric layer, the controllable dielectric layer is disposed between the first electrode layer and the at least one transmission line, the pitch P, the spacing S and the length L satisfy the following relationship:

, where k _sspp is the wave number of the electromagnetic wave signal transmitted through the at least one transmission line, _εr is the effective permittivity of the controllable dielectric layer, ω is the angular frequency of the electromagnetic wave signal transmitted through the at least one transmission line, c is speed of light. The electromagnetic wave transmission structure as described in claim 1, wherein each of the at least one transmission line has a transmission section, a reception section and a transmission section, the transmission section is connected between the reception section and the transmission section, and the dielectric The adjustable unit includes a plurality of first dielectric adjustable units overlapping one of the transmitting section and the receiving section, and a part of the antennas and the antennas of the transmitting section and the receiving section are adjacent to each other. The first dielectrically adjustable units are alternately arranged along an extending direction of the at least one transmission line. The electromagnetic wave transmission structure as claimed in item 2, wherein the dielectrically adjustable units further include a plurality of second dielectrically adjustable units overlapping the other one of the transmitting section and the receiving section, and adjacent to the The other part of the antennas and the second dielectric adjustable units of the transmitting section and the receiving section are alternately arranged along the extending direction. The electromagnetic wave transmission structure according to claim 3, wherein the at least one transmission line is a plurality of transmission lines extending in a first direction, the transmission lines are arranged along a second direction, and the antennas are respectively adjacent to the transmission lines a plurality of the receiving sections and a plurality of the transmitting sections, the dielectric adjustable units further include a plurality of third dielectric adjustable units overlapping the transmission sections of the transmission lines, and the third dielectric The adjustable units are respectively arranged in multiple columns and multiple rows along the first direction and the second direction. The electromagnetic wave transmission structure as claimed in claim 4, wherein the first electrode layer of each of the dielectrically adjustable units has a bottom parallel to the substrate and a side wall extending from the bottom in a bent manner, the side wall Surrounding the controllable dielectric layer, the first electrode layer and the at least one transmission line are adapted to generate an electric field for changing the effective dielectric constant of the controllable dielectric layer. The electromagnetic wave transmission structure as claimed in item 5, wherein any two adjacent ones of the third dielectrically adjustable units arranged along the first direction are provided between the two sidewalls of the two first electrode layers. Insulation. The electromagnetic wave transmission structure as described in claim 1, wherein each of the at least one transmission line has a transmission section, a reception section and a transmission section, the transmission section is connected between the reception section and the transmission section, and the at least one transmission line A plurality of transmission lines extending in a first direction, the transmission lines are arranged along a second direction, and the antennas are respectively adjacent to the plurality of receiving sections and the plurality of transmitting sections of the transmission lines, the intervening At least a part of the electrically adjustable units overlaps the plurality of transmission sections of the transmission lines, and is arranged in multiple columns and rows along the first direction and the second direction respectively. The electromagnetic wave transmission structure as claimed in claim 1, wherein the first electrode layer of each of the dielectrically adjustable units has a bottom parallel to the substrate and a side wall extending from the bottom in a bent manner, the side wall Surrounding the controllable dielectric layer, the first electrode layer and the at least one transmission line are adapted to generate an electric field for changing the effective dielectric constant of the controllable dielectric layer. The electromagnetic wave transmission structure as claimed in claim 1, wherein the at least one transmission line is a transmission line, and the distances between the antennas and the transmission line are the same, and the antennas are arranged along an extending direction of the transmission line, and have a symmetry axis , a diameter of each of the antennas decreases or increases with distance from the symmetry axis. The electromagnetic wave transmission structure as claimed in claim 1, wherein the at least one transmission line is a transmission line, the respective geometric centers of the antennas are at the same distance from the transmission line, and the antennas are arranged along an extension direction of the transmission line, and There is a symmetry axis, and a diameter of each of the antennas decreases or increases as it moves away from the symmetry axis. The electromagnetic wave transmission structure as claimed in claim 1, wherein the at least one transmission line is a transmission line, each of the antennas has the same diameter, the antennas are arranged along an extension direction of the transmission line, and have a symmetry axis, each A distance between the antennas and the transmission line increases with distance from the symmetry axis. The electromagnetic wave transmission structure as described in Claim 1, wherein each of the dielectrically adjustable units further includes: A second electrode layer is disposed on the surface of the substrate away from the at least one transmission line and overlaps the controllable dielectric layer. The first electrode layer and the second electrode layer are suitable for generating An electric field that controls the effective permittivity of the dielectric layer. The electromagnetic wave transmission structure as claimed in claim 1, wherein the controllable dielectric layer is a liquid crystal layer. The electromagnetic wave transmission structure according to claim 1, wherein the first electrode layer includes a plurality of first strip electrodes and a plurality of second strip electrodes, and the first strip electrodes and the second strip electrodes are Arranged alternately along the first direction and parallel to the second extensions, any adjacent first strip-shaped electrode and a second strip-shaped electrode are suitable for generating an effective dielectric for changing the controllable dielectric layer. An electric field with electric constant.

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