A high-power terahertz photoconductive hybrid coupler, design method and antenna array

Abstract

This invention relates to a high-power terahertz photoconductive combiner, its design method, and an antenna array. The combiner includes two sets of input transmission structures, two sets of intermediate transmission structures, an output structure, and a first combining choke structure disposed between the two sets of intermediate transmission structures. The antenna array consists of a dipole antenna and two opposing combiners. A bias structure with a second combining choke structure is connected externally to each combiner. The four signals are combined and radiated by the dipole antenna. The design method determines the conductor length and spacing based on the effective wavelength and combined phase of the electromagnetic wave. This invention employs a parallel double-line structure, eliminating the need for a thin substrate and a back-side grounding layer. It can combine four off-axis sources into a virtual point source along the optical axis, eliminating aberrations and wavefront distortion, and improving power combining efficiency and radiation performance.

Description

Technical Field

[0001] This application relates to the field of combiner technology, and in particular to a high-power terahertz photoconductive combiner, its design method, and an antenna array. Background Technology

[0002] A photoconductive antenna (PCA) is a core device that converts laser energy into terahertz signals through the photoelectric effect. However, the output power of a single photoconductive antenna is limited, typically at least two orders of magnitude lower than that of a solid-state terahertz source, which severely restricts its application in scenarios requiring high signal-to-noise ratios or long-range detection. To overcome this bottleneck, assembling multiple photoconductive antenna elements into an array to synthesize a higher-power output has become an important development direction.

[0003] Currently, achieving efficient power combining and radiation in photoconductive antenna arrays mainly faces the following key technical challenges: 1. Poor compatibility of existing combiner structures with the terahertz frequency band: Traditional power combiners (such as those based on coplanar waveguides or microstrip lines) face several drawbacks in the terahertz band. To achieve effective electromagnetic field confinement and low-loss transmission, these structures typically require extremely thin substrates or the fabrication of a metal grounding layer on the back of the substrate. This not only significantly increases the difficulty and cost of micro / nano fabrication, but also causes conductor losses, dielectric losses, and radiation losses caused by mode leakage to increase sharply with increasing frequency, resulting in a significant decrease in combining efficiency and making it difficult to meet the low-loss combining requirements of terahertz arrays.

[0004] 2. Mismatch between discrete radiation sources and lenses in the array: Traditional radiation schemes place each antenna element on a substrate according to a certain pattern and radiate into free space through a hemispherical lens. However, when such a multi-physical-location radiation source array is combined with a subsequent large-aperture lens or collimating optical system, elements located outside the lens optical axis will produce severe off-axis aberrations. This leads to distortion of the synthesized wavefront, focal diffusion, and inability to achieve effective energy convergence, greatly reducing the overall radiation efficiency and performance of the system, thus defeating the original intention of increasing power through arraying.

[0005] Therefore, there is an urgent need for a four-in-one combiner that is simple in structure, low in cost, suitable for the terahertz band, and can solve the mismatch between the four off-axis radiation sources of the photoconductive antenna array and the radiation lens. Summary of the Invention

[0006] To overcome the technical problems of the above-mentioned existing technology, such as complex structure, difficulty in adapting to the terahertz frequency band, and mismatch between the four off-axis radiation sources of the photoconductive antenna array and the radiation lens, the present invention provides a high-power terahertz photoconductive combiner, design method, and antenna array.

[0007] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows: A high-power terahertz photoconductive combiner, the combiner comprising: a first input transmission structure, a second input transmission structure, a first intermediate transmission structure, a second intermediate transmission structure, and an output structure; The first input transmission structure includes a first straight conductor (1) and a second straight conductor (2) arranged in parallel intervals; the second input transmission structure includes a third straight conductor (3) and a fourth straight conductor (4) arranged in parallel intervals; the first intermediate transmission structure includes a fifth straight conductor (5) and a sixth straight conductor (6) arranged in parallel intervals; the second intermediate transmission structure includes a seventh straight conductor (7) and an eighth straight conductor (8) arranged in parallel intervals; the output structure includes a ninth straight conductor (9) and a tenth straight conductor (10) arranged in parallel intervals. The two ends of the fifth straight conductor (5) are connected to the first straight conductor (1) and the ninth straight conductor (9) respectively. The two ends of the eighth straight conductor (8) are connected to the fourth straight conductor (4) and the tenth straight conductor (10) respectively. The sixth straight conductor (6) is connected to the second straight conductor (2). The seventh straight conductor (7) is connected to the third straight conductor (3).

[0008] Preferably, the angle between the first straight conductor (1) and the fifth straight conductor (5), the angle between the second straight conductor (2) and the sixth straight conductor (6), the angle between the third straight conductor (3) and the seventh straight conductor (7), the angle between the fourth straight conductor (4) and the eighth straight conductor (8), the angle between the fifth straight conductor (5) and the ninth straight conductor (9), and the angle between the eighth straight conductor (8) and the tenth straight conductor (10) are all greater than 90° and less than 180°.

[0009] Preferably, there is a gap between the end of the sixth straight conductor (6) away from the second straight conductor (2) and the end of the seventh straight conductor (7) away from the third straight conductor (3).

[0010] Preferably, the end of the sixth straight conductor (6) away from the second straight conductor (2) and / or the end of the seventh straight conductor (7) away from the third straight conductor (3) are connected to a first choke structure (13).

[0011] A high-power terahertz photoconductive antenna array, comprising a dipole antenna and two combiners as described in any one of the above claims; The two combiners are arranged facing each other, and the dipole antenna is arranged between the two combiners; The dipole antenna includes an upper arm (15) and a lower arm (16). The upper arm (15) is connected to the ninth straight conductor (9) of both combiners, and the lower arm (16) is connected to the tenth straight conductor (10) of both combiners.

[0012] Preferably, the antenna array further includes a bias structure, wherein the first input transmission structure and the second transmission structure of the two combiners are each connected to one of the bias structures.

[0013] Preferably, the bias structure includes an eleventh straight conductor (11) and a twelfth straight conductor (12) arranged in parallel and spaced apart. The eleventh straight conductor (11) is connected to the first straight conductor (1), and the twelfth straight conductor (12) is connected to the second straight conductor (2).

[0014] Preferably, the eleventh straight conductor (11) is provided with a second choke structure (14) on one side of the twelfth straight conductor (12) and / or the twelfth straight conductor (12) is provided with a side of the eleventh straight conductor (11).

[0015] Preferably, the eleventh straight conductor is provided with a second choke structure on the side of the eleventh straight conductor relative to the twelfth straight conductor and the twelfth straight conductor is provided with a side of the eleventh straight conductor, and the two second choke structures are parallel to each other and have the same size.

[0016] A design method for a high-power terahertz photoconductive combiner includes: Calculate the effective wavelength of the electromagnetic wave transmitted in the two parallel straight wires of each of the first input transmission structure, the second input transmission structure, the first intermediate transmission structure, the second intermediate transmission structure, and the output structure; Calculate the phase of the two input signals at the point of combination; The length and spacing of each straight conductor are calculated based on the effective wavelength of the electromagnetic wave and the phase of the two input signals at the point of synthesis.

[0017] Compared with the prior art, the beneficial effects of the technical solution of the present invention are: This invention employs parallel dual-line arrays as the core transmission and combining structure, replacing traditional coplanar waveguide or microstrip line solutions. This structure eliminates the need for ultra-thin substrates or back metal grounding layers, significantly reducing the difficulty and complexity of micro / nano fabrication in the terahertz band and effectively controlling manufacturing costs. Furthermore, this invention combines four signals into a single stream internally using two opposing combiners, which are then radiated by a centrally integrated dipole antenna. This effectively converts multiple physically discrete radiation sources into a single virtual point source located on the optical axis of the optical system, completely avoiding aberrations, focus spread, and wavefront distortion caused by multiple off-axis sources when combined with subsequent lenses. It also solves the technical problem of mismatch between four off-axis radiation sources in a photoconductive antenna array and the radiating lens. Attached Figure Description

[0018] Figure 1 This is a structural diagram of a high-power terahertz photoconductive combiner according to an embodiment; Figure 2 One of the structural diagrams of a high-power terahertz photoconductive antenna array is shown in the embodiment. Figure 3 This is the second structural diagram of a high-power terahertz photoconductive antenna array as an example. Figure 4 This is a structural diagram of a high-power terahertz photoconductive antenna array dipole antenna according to an embodiment; Figure 5 This is a structural diagram of a high-power terahertz photoconductive antenna array bias structure according to an embodiment; Figure 6 This is a schematic diagram of electromagnetic wave transmission of a high-power terahertz photoconductive antenna array, as shown in the embodiment. In the diagram, 1-first straight conductor; 2-second straight conductor; 3-third straight conductor; 4-fourth straight conductor; 5-fifth straight conductor; 6-sixth straight conductor; 7-seventh straight conductor; 8-eighth straight conductor; 9-ninth straight conductor; 10-tenth straight conductor; 11-eleventh straight conductor; 12-twelfth straight conductor; 13-first choke structure; 14-second choke structure; 15-upper arm; 16-lower arm. Detailed Implementation

[0019] The accompanying drawings are for illustrative purposes only and should not be construed as limiting the scope of this application. To better illustrate this embodiment, some parts in the accompanying drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions; It will be understood by those skilled in the art that certain well-known structures and their descriptions may be omitted in the accompanying drawings.

[0020] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0021] Example 1 This embodiment provides a high-power terahertz photoconductive combiner, the structural diagram of which is shown below. Figure 1 As shown, the combiner includes: a first input transmission structure, a second input transmission structure, a first intermediate transmission structure, a second intermediate transmission structure, and an output structure; The first input transmission structure includes a first straight wire 1 and a second straight wire 2 arranged in parallel and spaced apart; the second input transmission structure includes a third straight wire 3 and a fourth straight wire 4 arranged in parallel and spaced apart; the first intermediate transmission structure includes a fifth straight wire 5 and a sixth straight wire 6 arranged in parallel and spaced apart; the second intermediate transmission structure includes a seventh straight wire 7 and an eighth straight wire 8 arranged in parallel and spaced apart; the output structure includes a ninth straight wire 9 and a tenth straight wire 10 arranged in parallel and spaced apart. The combiner is integrated on the surface of a low-temperature grown gallium arsenide substrate, replacing the traditional combiner structure.

[0022] Preferably, the two ends of the fifth straight conductor 5 are connected to the first straight conductor 1 and the ninth straight conductor 9, respectively; the two ends of the eighth straight conductor 8 are connected to the fourth straight conductor 4 and the tenth straight conductor 10, respectively; the sixth straight conductor 6 is connected to the second straight conductor 2; and the seventh straight conductor 7 is connected to the third straight conductor 3.

[0023] In this embodiment, the length of the straight wires in the first input transmission structure and the second input transmission structure is 50μm, the width is 10μm, and the wire spacing is 10μm. The center-to-center distance between the first input transmission structure and the second input transmission structure in the same combiner is 100μm. In the first intermediate transmission structure and the second intermediate transmission structure, the length of the fifth straight wire 5 and the eighth straight wire 8 is 78μm, and the length of the sixth straight wire 6 and the seventh straight wire 7 is 62μm. The wire spacing between the fifth straight wire 5 and the sixth straight wire 6, and the wire width between the seventh straight wire 7 and the eighth straight wire 8 are all 6μm, and the wire width is 6μm. In the output structure, the length of the ninth straight wire 9 and the tenth straight wire 10 is 50μm, the width is 10μm, and the wire spacing is 10μm.

[0024] This embodiment uses parallel double lines as the core transmission and combining structure, replacing the traditional coplanar waveguide or microstrip line scheme. This structure does not require the fabrication of an extremely thin substrate or a back metal grounding layer, thereby significantly reducing the difficulty and complexity of micro-nano fabrication in the terahertz band and effectively controlling manufacturing costs.

[0025] Preferably, the angles between the first straight conductor 1 and the fifth straight conductor 5, the angles between the second straight conductor 2 and the sixth straight conductor 6, the angles between the third straight conductor 3 and the seventh straight conductor 7, the angles between the fourth straight conductor 4 and the eighth straight conductor 8, the angles between the fifth straight conductor 5 and the ninth straight conductor 9, and the angles between the eighth straight conductor 8 and the tenth straight conductor 10 are all greater than 90° and less than 180°.

[0026] In this embodiment, the angles between the first straight conductor 1 and the fifth straight conductor 5, the second straight conductor 2 and the sixth straight conductor 6, the third straight conductor 3 and the seventh straight conductor 7, the fourth straight conductor 4 and the eighth straight conductor 8, the fifth straight conductor 5 and the ninth straight conductor 9, and the eighth straight conductor 8 and the tenth straight conductor 10 are all 135°.

[0027] In this embodiment, by setting the length of each straight conductor and the spacing between conductors at this specific angle, the design is simplified, the design cost is saved, and no additional performance loss is caused.

[0028] Preferably, there is a gap between the end of the sixth straight conductor 6 away from the second straight conductor 2 and the end of the seventh straight conductor 7 away from the third straight conductor 3. In this embodiment, the gap between the end of the sixth straight conductor 6 away from the second straight conductor 2 and the end of the seventh straight conductor 7 away from the third straight conductor 3 is set to 2μm. The input transmission structure of the combiner needs to be biased with positive and negative voltages. At this time, the internal region of the two-way combiner will cause a short circuit. A gap needs to be set to prevent the two inputs from short-circuiting at the combiner point.

[0029] Preferably, the end of the sixth straight conductor 6 away from the second straight conductor 2 and / or the end of the seventh straight conductor 7 away from the third straight conductor 3 are connected to a first combining choke structure 13. In this embodiment, the first combining choke structure 13 is used to improve the ability to prevent short circuits between the two inputs at the combining point.

[0030] Compared to traditional design methods based on coplanar waveguides or microstrip line combiners, this invention uses parallel twin lines to confine and transmit electromagnetic waves. In the terahertz band, it does not require stringent conditions such as thin substrates, has a simple structure, and high synthesis efficiency.

[0031] Example 2 This embodiment provides a high-power terahertz photoconductive antenna array, the structure of which is shown in the figure below. Figure 2 As shown, it includes a dipole antenna and two combiners as described in Embodiment 1; The two combiners are arranged facing each other, and the dipole antenna is arranged between the two combiners; The structure diagram of the dipole antenna is as follows: Figure 4 As shown, the dipole antenna includes an upper arm 15 and a lower arm 16. The upper arm 15 is connected to the ninth straight conductor 9 of both combiners, and the lower arm 16 is connected to the tenth straight conductor 10 of both combiners.

[0032] The "four-way combined-one radiation" approach proposed in this invention solves the off-axis loss problem when using lenses in photoconductive antenna arrays, effectively reducing the design difficulty of the lenses and providing a new direction for improving the radiation power of photoconductive antenna arrays. This invention's antenna array solves the technical problems of high processing difficulty and cost associated with traditional combining structures; secondly, it solves the technical problem of high loss in the terahertz band when traditional combining structures are used on high dielectric constant surfaces; and thirdly, it solves the problem of mismatch between the four off-axis radiation sources and the radiation lens, leading to the lens's inability to focus and reduced beam quality.

[0033] Discrete photoconductive antenna arrays are equivalent to multiple radiation sources, which are off-axis for the lens. This invention uses a dual-wire combiner to adjust the radiation to central radiation. The electromagnetic waves transmitted inside the combiner are surface-transmitted, while the lens is located at the bottom of the substrate and cannot be used for lens radiation. This invention proposes placing two pairs of 2x1 combiners opposite each other, so the electromagnetic waves will propagate in the direction of high dielectric constant, achieving radiation redirection. A schematic diagram is shown below. Figure 6 As shown; when electromagnetic waves travel from a low dielectric constant medium (such as air in this embodiment, ε) r=1 Incident on a high dielectric constant medium (such as the low-temperature gallium arsenide substrate in this embodiment: LT-GaAs, dielectric constant ε) r When the interface is 12.9), electromagnetic waves tend to propagate towards the lower impedance direction. That is, the medium with lower impedance has a stronger "binding effect" on electromagnetic waves, which will guide the electromagnetic wave energy to concentrate on its own side. In this embodiment, two two-in-one combiners set in opposite directions form an antenna array. The electromagnetic waves combined to the center are radiated towards the substrate through an integrated single dipole antenna.

[0034] In this embodiment, the distance between the upper arm 15 and the lower arm 16 of the dipole antenna is 10 μm, the width of each arm is 10 μm, and the length of each arm is 188 μm. Both combiners and the dipole antenna of the antenna array are made of gold with a metal thickness of 0.4 μm. The substrate is LT-GaAs (low-temperature grown gallium arsenide) with a substrate thickness of 350 μm. The antenna array of this invention is suitable for thick substrates with a thickness greater than 100 μm, and the antenna array of this invention has relatively low requirements for substrate thickness.

[0035] Preferably, the antenna array further includes a bias structure, wherein the first input transmission structure and the second transmission structure of the two combiners are each connected to one of the bias structures, and the structural diagram of the bias structure is shown below. Figure 5 As shown, the bias structure includes an eleventh straight conductor 11 and a twelfth straight conductor 12 arranged in parallel intervals. The eleventh straight conductor 11 is connected to the first straight conductor 1, and the twelfth straight conductor 12 is connected to the second straight conductor 2. The antenna array structure diagram is shown below. Figure 3 As shown, the bias structure is used to connect the input transmission structure at one end and the bias voltage at the other end. In this embodiment, the spacing between the eleventh straight conductor 11 and the twelfth straight conductor 12 of the bias structure is 10 μm, and the conductor width is 10 μm.

[0036] Preferably, the eleventh straight conductor 11 is provided with a second choke structure 14 on one side of the twelfth straight conductor 12 and / or the twelfth straight conductor 12 is provided with one side of the eleventh straight conductor 11. If the bias structure is directly connected, electromagnetic radiation will leak along the bias structure. Therefore, a second choke structure 14 needs to be added in the gap of the bias structure. The multiple second choke structures 14 do not contact each other.

[0037] In this embodiment, the second combining choke structure 14 has a length of 72μm and a width of 4μm. The distance between the second combining choke structure 14 closest to the first input transmission structure and the second input transmission structure is 50μm.

[0038] The eleventh straight conductor is provided with a second choke structure on the side of the twelfth straight conductor and the twelfth straight conductor is provided with a side of the eleventh straight conductor, and the two second choke structures are parallel to each other and have the same size.

[0039] The signal is transmitted in the form of a traveling wave along the parallel double lines of the combiner. With the two combiners facing each other, the two planar electromagnetic waves meet and propagate towards the direction of higher dielectric constant, achieving the goal of combining four signals into one. An integrated terahertz radiating antenna is directly connected at the center; in this embodiment, a dipole antenna is used. The combined signal is radiated through this single antenna, realizing the synthesis of four off-axis sources into a virtual point source on the optical axis, eliminating aberrations and wavefront distortion. This design simplifies the traditional "multi-channel discrete antenna array" into a "single-channel high-performance antenna."

[0040] Example 3 This embodiment provides a design method for a high-power terahertz photoconductive combiner, including: Calculate the effective wavelength of the electromagnetic wave transmitted in the two parallel straight wires of the first input transmission structure, the second input transmission structure, the first intermediate transmission structure, the second intermediate transmission structure, and the output structure; Calculate the phase of the two input signals at the point of combination; The length and spacing of each straight conductor are calculated based on the effective wavelength of the electromagnetic wave and the phase of the two input signals at the point of synthesis.

[0041] In the specific implementation process, this embodiment discloses a design method for a high-power terahertz photoconductive combiner and antenna array. The length and spacing of each straight conductor are calculated according to the electromagnetic wave wavelength and the two-line transmission formula to ensure phase matching. The two input signals need to be superimposed in phase at the combining port. Therefore, the length of the straight conductor needs to be designed according to the effective wavelength and phase conditions. The length of the straight conductor needs to be 1 / 4 of the effective wavelength or a multiple thereof. First, the effective wavelength of the electromagnetic wave propagating within the parallel double lines on the substrate is calculated. The effective wavelength is expressed as:

[0042] in, The wavelength of an electromagnetic wave in free space. It is the equivalent relative permittivity. , The dielectric constant of gallium arsenide grown at low temperature. The free space dielectric constant; The propagation constant is calculated based on the effective wavelength:

[0043] Calculate the transmission phase of each input signal to the combining point based on the propagation constant, ensuring that the transmission phase satisfies:

[0044] in, This refers to the length of the transmission channel; And ensure that all signals are superimposed in phase at the combining point, satisfying the phase condition:

[0045] in, The length of transmission channel one, that is, the length from the input end of the input transmission structure to the output end of the output structure, is given in this embodiment. This can be equivalent to adding the lengths of the following three segments: length of the first straight conductor 1 + length of the ninth straight conductor 9 + (length of the fifth straight conductor 5 + length of the sixth straight conductor 6) / 2; The length of transmission channel two is the same as described above. This can be equivalent to adding the lengths of the following three segments: the length of the third straight conductor is 3 + the length of the tenth straight conductor is 10 + (the length of the seventh straight conductor is 7 + the length of the eighth straight conductor is 8) / 2, where n is a positive integer; For the inclined section of the middle structure, calculate the phase of the inner channel based on the lengths of the sixth straight conductor 6 and the seventh straight conductor 7, and the phase of the outer channel based on the lengths of the fifth straight conductor 5 and the eighth straight conductor 8, respectively, to make the phases of the inner and outer channels synchronized. Then, adjust the lengths of the fifth straight conductor 5 and the eighth straight conductor 8 to ensure they are in phase, thus achieving phase matching.

[0046] in, The propagation constant of the inner channel. The outer channel propagation constant, The length of the inner channel is equivalent to the length of the straight conductor connected to the first choke structure 13. The length of the outer channel is equivalent to the length of another straight conductor opposite to the straight conductor connected to the first choke structure 13; The lengths of each pair of parallel, spaced straight conductors are set to integer multiples of one-quarter of the effective wavelength. The lengths of the inner and outer conductors are determined using the propagation constant extracted from electromagnetic simulation to compensate for the transmission phase difference. The spacing between each pair of parallel straight conductors is adjusted, with the spacing between the two conductors reduced in the middle inclined transmission section to enhance electromagnetic field confinement. The input and output transmission structures maintain a fixed spacing to achieve impedance matching. The angles between interconnected straight conductors are set such that the tilt angles between the input and intermediate transmission structures, and between the intermediate and output structures, are greater than 90° and less than 180°, while the tilt angle between the intermediate transmission structure and the first combining choke structure 13 is less than 90°. A gap exists between the end of the sixth straight conductor 6 away from the second straight conductor 2 and the end of the seventh straight conductor 7 away from the third straight conductor 3 in the combiner. The end of the sixth straight conductor 6 away from the second straight conductor 2 and / or the end of the seventh straight conductor 7 away from the third straight conductor 3 are connected to the first combining choke structure 13. A second combining choke structure 14 is set inside the parallel conductors of the bias structure. The choke structures are parallel to each other and of the same size to suppress signal leakage.

[0047] Modeling and simulation were performed on an LT-GaAs substrate using CST electromagnetic simulation software. The wire length, spacing, connection angle, and choke structure dimensions were optimized to verify the power combining effect and radiation performance of four terahertz signals. Optimal structural parameters were determined, and the design of a high-power terahertz photoconductive combiner and antenna array was completed. Specifically, a signal input port was set at the front end of the input transmission structure. Each input port is connected by a gradually changing impedance matching transition section. The input signals are transmitted and naturally superimposed in the main body region of the parallel double lines, achieving vector power combining. By optimizing the length and spacing of each straight wire, phase synchronization of each signal at the combining point was ensured, maximizing the combining efficiency. Finally, the power combining effect was verified using CST electromagnetic simulation software, and the optimal dimensional parameters were determined.

[0048] The same or similar labels correspond to the same or similar parts; The terms used to describe positional relationships in the accompanying drawings are for illustrative purposes only and should not be construed as limiting this application. Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A high-power terahertz photoconductive combiner, characterized in that, The combiner includes: a first input transmission structure, a second input transmission structure, a first intermediate transmission structure, a second intermediate transmission structure, and an output structure; The first input transmission structure includes a first straight conductor (1) and a second straight conductor (2) arranged in parallel intervals; the second input transmission structure includes a third straight conductor (3) and a fourth straight conductor (4) arranged in parallel intervals; the first intermediate transmission structure includes a fifth straight conductor (5) and a sixth straight conductor (6) arranged in parallel intervals; the second intermediate transmission structure includes a seventh straight conductor (7) and an eighth straight conductor (8) arranged in parallel intervals; the output structure includes a ninth straight conductor (9) and a tenth straight conductor (10) arranged in parallel intervals. The two ends of the fifth straight conductor (5) are connected to the first straight conductor (1) and the ninth straight conductor (9) respectively. The two ends of the eighth straight conductor (8) are connected to the fourth straight conductor (4) and the tenth straight conductor (10) respectively. The sixth straight conductor (6) is connected to the second straight conductor (2). The seventh straight conductor (7) is connected to the third straight conductor (3).

2. A high power terahertz photoconductive hybridizer according to claim 1, wherein The angle between the first straight conductor (1) and the fifth straight conductor (5), the angle between the second straight conductor (2) and the sixth straight conductor (6), the angle between the third straight conductor (3) and the seventh straight conductor (7), the angle between the fourth straight conductor (4) and the eighth straight conductor (8), the angle between the fifth straight conductor (5) and the ninth straight conductor (9), and the angle between the eighth straight conductor (8) and the tenth straight conductor (10) are all greater than 90° and less than 180°.

3. The high power terahertz photoconductive hybrid coupler of claim 1, wherein, There is a gap between the end of the sixth straight conductor (6) away from the second straight conductor (2) and the end of the seventh straight conductor (7) away from the third straight conductor (3).

4. A high power terahertz photoconductive hybridizer according to claim 3, wherein The end of the sixth straight conductor (6) away from the second straight conductor (2) and / or the end of the seventh straight conductor (7) away from the third straight conductor (3) are connected to a first choke structure (13).

5. A high power terahertz photoconductive antenna array, characterized by, Includes a dipole antenna and the combiner as described in any one of claims 1-4; The two combiners are arranged facing each other, and the dipole antenna is arranged between the two combiners; The dipole antenna includes an upper arm (15) and a lower arm (16). The upper arm (15) is connected to the ninth straight conductor (9) of both combiners, and the lower arm (16) is connected to the tenth straight conductor (10) of both combiners.

6. The high-power terahertz photoconductive antenna array of claim 5, wherein, The antenna array further includes a bias structure, and the first input transmission structure and the second transmission structure of the two combiners are each connected to one of the bias structures.

7. The high power terahertz photoconductive antenna array of claim 6, wherein, The bias structure includes an eleventh straight conductor (11) and a twelfth straight conductor (12) arranged in parallel and spaced apart. The eleventh straight conductor (11) is connected to the first straight conductor (1), and the twelfth straight conductor (12) is connected to the second straight conductor (2).

8. A high-power terahertz photoconductive antenna array according to claim 7, characterized in that, The eleventh straight conductor (11) is provided with a second choke structure (14) on one side of the twelfth straight conductor (12) and / or the twelfth straight conductor (12) is provided with a side of the eleventh straight conductor (11).

9. The high power terahertz photoconductive antenna array of claim 8, wherein, The eleventh straight conductor is provided with a second choke structure on the side of the twelfth straight conductor and the twelfth straight conductor is provided with a second choke structure, and the two second choke structures are parallel to each other and have the same size.

10. A method for designing a high power terahertz photoconductive hybridizer, characterized in that, include: Calculate the effective wavelength of the electromagnetic wave transmitted in the two parallel straight wires of each of the first input transmission structure, the second input transmission structure, the first intermediate transmission structure, the second intermediate transmission structure, and the output structure; Calculate the phase of the two input signals at the point of combination; The length and spacing of each straight conductor are calculated based on the effective wavelength of the electromagnetic wave and the phase of the two input signals at the point of synthesis.

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