CN-117254233-B - Broadband waveguide-grounding coplanar waveguide transition structure based on double dipole antenna

CN117254233BCN 117254233 BCN117254233 BCN 117254233BCN-117254233-B

Abstract

The invention discloses a broadband waveguide-grounded coplanar waveguide transition structure based on a double-dipole antenna, which belongs to the technical field of terahertz and comprises an input end waveguide, a rectangular metal cavity, a terahertz integrated chip and an output end waveguide, wherein the terahertz integrated chip comprises a substrate, an integrated structure, back gold and two first dipole antenna transition sections, the integrated structure comprises two coplanar waveguide center conduction bands, a first coplanar waveguide grounding layer, two second coplanar waveguide grounding layers, a plurality of air bridges and four antenna structures, and the antenna structures and the first dipole antenna transition sections corresponding to the same end areas form a pair of dipole antennas, and the total of four pairs of dipole antennas. According to the invention, the transition section connected with the coplanar waveguide ground layer in the traditional on-chip dipole antenna is placed on the back gold layer, so that the occupied area of the dipole antenna is greatly reduced, the electromagnetic energy coupling efficiency is improved, the bandwidth of the transition structure is expanded, the structure is simple, the processing is easy, and the application prospect is good.

Inventors

ZHANG YONG
Liu Guangru
ZHANG YIMING
ZHU HUALI
HU JIANG

Assignees

电子科技大学

Dates

Publication Date: 20260512
Application Date: 20231008

Claims (7)

1. The broadband waveguide-grounded coplanar waveguide transition structure based on the double dipole antenna is characterized by comprising an input end waveguide, a rectangular metal cavity, an output end waveguide and a terahertz integrated chip arranged in the rectangular metal cavity in sequence, wherein the terahertz integrated chip is perpendicular to H surfaces of the input end waveguide and the output end waveguide; The terahertz integrated chip comprises a substrate, an integrated structure processed on the front surface of the substrate, back gold processed on the back surface of the substrate, two first dipole antenna transition sections, wherein the integrated structure comprises two coplanar waveguide center conduction bands arranged along the signal transmission direction, a first coplanar waveguide grounding layer positioned between the two coplanar waveguide center conduction bands, two second coplanar waveguide grounding layers respectively positioned on the outer sides of the two coplanar waveguide center conduction bands, a plurality of air bridges used for connecting the first coplanar waveguide grounding layers and the second coplanar waveguide grounding layers, and four antenna structures; the first coplanar waveguide grounding layer is provided with a row of metal through holes connected with the back gold along the signal transmission direction, and the periphery of the second coplanar waveguide grounding layer is provided with a plurality of metal through holes connected with the back gold; The two ends of the two coplanar waveguide center conduction bands are respectively connected with the corresponding antenna structures, the two first dipole antenna transition sections are respectively connected with the two ends of the back gold area corresponding to the first coplanar waveguide grounding layer, and the antenna structures and the first dipole antenna transition sections corresponding to the same end area form a pair of dipole antennas, namely four pairs of dipole antennas in total.
2. The dual dipole antenna-based broadband waveguide-grounded coplanar waveguide transition structure according to claim 1, wherein the four antenna structures are not the same size.
3. The dual dipole antenna-based broadband waveguide-to-ground coplanar waveguide transition structure according to claim 1, wherein the antenna structure comprises a second dipole antenna transition section and a coupling stub in sequence.
4. The broadband waveguide-grounded coplanar waveguide transition structure based on a double dipole antenna according to claim 3, wherein the coupling stub comprises a short stub and a polygonal coupling disc in sequence, wherein the short stub is perpendicular to the transition section of the second dipole antenna, and the maximum dimension of the polygonal coupling disc is larger than the width of the short stub.
5. The dual dipole antenna based broadband waveguide-to-ground coplanar waveguide transition structure according to claim 4, wherein by adjusting the length and width of the first dipole antenna transition section, the length and width of the second dipole antenna transition section, the length and width of the short stub, and the maximum size of the polygonal coupling disk, energy input from the input end waveguide is coupled to the dipole antenna with maximum efficiency.
6. The dual dipole antenna-based broadband waveguide-grounded coplanar waveguide transition structure according to claim 1, wherein the input end waveguide comprises a standard rectangular input waveguide and a reduced-height input waveguide in sequence, and the output end waveguide comprises a reduced-height output waveguide and a standard rectangular output waveguide in sequence.
7. The broadband waveguide-grounded coplanar waveguide transition structure based on a double dipole antenna according to claim 6, wherein the tail end of the elevation-reduced input waveguide and the head end of the elevation-reduced output waveguide respectively extend into the rectangular metal cavity, and the dipole antennas at both ends are respectively positioned in the tail end of the elevation-reduced input waveguide and the head end of the elevation-reduced output waveguide.

Description

Broadband waveguide-grounding coplanar waveguide transition structure based on double dipole antenna Technical Field The invention belongs to the technical field of terahertz, and particularly relates to a broadband waveguide-grounded coplanar waveguide transition structure based on a double-dipole antenna. Background The terahertz frequency range is usually 0.1 THz-10 THz, the wave band is between the microwave wave band and the infrared wave band, and the transition region from electronics to photonics is formed. The terahertz wave has unique characteristics of transient property, broadband property, low energy and the like due to the special position of the terahertz wave, and has wide application in security check, imaging, radar, communication, astronomy and other directions. Terahertz monolithic integrated circuits are important foundation stones for the future electronic information industry. The grounded coplanar waveguide has a firm grounding structure and lower loss in a high-frequency band, so that the grounded coplanar waveguide is often used as a transmission line of a terahertz monolithic integrated circuit. However, because the terahertz wave frequency is higher and the size is smaller, when the transition structure from the waveguide to the grounded coplanar waveguide is designed, the traditional gold wire bonding mode can introduce great loss, so that the transition can be realized in the form of on-chip antenna coupling. In 2011, v.radiic et al designed a transition structure from a waveguide of an integrated double dipole antenna to a coplanar waveguide based on a 50nm InP HEMT (high electron mobility transistor) process in article "220-GHz solid-state power amplifier modules", but the designed double dipole antenna transition structure placed the dipole antenna all on the front side of the chip, not only occupied a larger area, but also the designed transition structure had poor performance, and the relative bandwidth at a return loss of 8dB was only 19.5%. In order to solve the above problems, how to design a transition structure from a small-area and wide-bandwidth on-chip integrated double-dipole antenna waveguide to a grounded coplanar waveguide on the basis of a traditional double-dipole antenna is a problem to be solved. Disclosure of Invention Aiming at the problems in the prior art, the invention provides a broadband waveguide-grounded coplanar waveguide transition structure based on a double dipole antenna, which reduces the occupied area of the antenna, further improves the electromagnetic energy coupling efficiency and realizes the transition of a broadband and high-performance terahertz waveguide-plane transmission line. The technical scheme adopted by the invention is as follows: The broadband waveguide-grounded coplanar waveguide transition structure based on the double dipole antenna comprises an input end waveguide, a rectangular metal cavity, an output end waveguide and a terahertz integrated chip arranged in the rectangular metal cavity in sequence, wherein the terahertz integrated chip is perpendicular to H surfaces of the input end waveguide and the output end waveguide; The terahertz integrated chip comprises a substrate, an integrated structure processed on the front surface of the substrate, back gold processed on the back surface of the substrate, two first dipole antenna transition sections, wherein the integrated structure comprises two coplanar waveguide center conduction bands arranged along the signal transmission direction, a first coplanar waveguide grounding layer positioned between the two coplanar waveguide center conduction bands, two second coplanar waveguide grounding layers respectively positioned on the outer sides of the two coplanar waveguide center conduction bands, a plurality of air bridges used for connecting the first coplanar waveguide grounding layers and the second coplanar waveguide grounding layers, and four antenna structures; the first coplanar waveguide grounding layer is provided with a row of metal through holes connected with the back gold along the signal transmission direction, and the periphery of the second coplanar waveguide grounding layer is provided with a plurality of metal through holes connected with the back gold; The two ends of the two coplanar waveguide center conduction bands are respectively connected with the corresponding antenna structures, the two first dipole antenna transition sections are respectively connected with the two ends of the back gold area corresponding to the first coplanar waveguide grounding layer, and the antenna structures and the first dipole antenna transition sections corresponding to the same end area form a pair of dipole antennas, namely four pairs of dipole antennas in total. Further, the four antenna structures are not of the same size. Further, the antenna structure includes a second dipole antenna transition section and a coupling stub in sequence. Further, the coupling branches com