Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Cassegrain antenna

A Cassegrain antenna and antenna technology, applied in the direction of antenna, antenna grounding switch structure connection, electrical components, etc., can solve the problems of narrow beam and target loss

Active Publication Date: 2020-01-31
NANJING UNIV OF AERONAUTICS & ASTRONAUTICS
View PDF6 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

But traditional Cassegrain antennas have a narrow beam across the frequency band, and slight offsets can cause target loss

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Cassegrain antenna
  • Cassegrain antenna
  • Cassegrain antenna

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0050] Embodiment 1, a Cassegrain antenna, comprising a feed antenna 11, a main reflector 13, a secondary reflector 12, and a main and secondary reflector fixing device 14; the feed antenna 11 is a conical horn in a horn antenna, The main reflector 13 is in the form of a paraboloid, and the secondary reflector 12 is replaced by a frequency selective surface 16, such as figure 2 As shown, the frequency selective surface can generate resonance at some specific frequency points, so that the electromagnetic wave at this frequency point is transmitted, resulting in a wider beam width, while it is reflected at other frequency points, and the pattern narrower.

[0051] Adopting this scheme greatly improves the performance of the mobile communication system, such as Figure 5 As shown, the working frequency band of the antenna is 8-14.5GHz and 29-34GHz, its return loss in the working frequency band is less than -10dB, the gain at 9GHz is 6.93dB, and the beam width is 86.0°; the gain...

Embodiment 2

[0057] Embodiment 2, at the center of the frequency selective surface 16 described in Embodiment 1, a square hole with a side length of about 2 times the working wavelength (4-7mm) is opened, such as image 3 As shown, the opening design has no great influence on the reflection and transmission characteristics of the antenna, but the reduction of the reflection at the center can improve the standing wave characteristics of the antenna. Reflection can effectively reduce the reflection of the antenna, reduce the return loss of the back lobe and the antenna. This implementation method makes the return loss of the antenna less than 15dB, the gain is increased to 1dB, and the back lobe level is lower than that without openings. 3dB, such as Figure 14-16 shown.

Embodiment 3

[0058] Embodiment 3, the frequency selective surface 16 described in Embodiment 1 is composed of two 8×4 unit slices forming an inclination angle group, and the inclination angle is 8-12°, such as Figure 4 As shown, the incident angle of the electromagnetic wave has a certain change, but it has little effect on its transmission characteristics, and its reflection characteristics change the direction of the reflected wave due to the change of the angle, and the reflected wave received by the feed antenna is small, effectively improving Standing wave characteristics; the electromagnetic wave is radiated from the conical horn 11 to the sub-reflecting surface, because the sub-reflecting surface has a certain angle to the incident wave, so the vertical reflection of the electromagnetic wave can be avoided, and the return loss of the antenna can be reduced to less than - 15dB effect, such as Figure 17-19 shown.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention relates to a Cassegrain antenna. The Cassegrain antenna comprises a feed source antenna (11), a main reflecting surface (13), an auxiliary reflecting surface and a main and auxiliary reflecting surface fixing device (14); the feed source antenna (11) is a conical horn in a horn antenna; the main reflecting surface (13) is in a paraboloid form; the auxiliary surface is replaced by a frequency selective surface (15); the frequency selective surface can generate resonance at the frequency points of 8 GHz to 14.5 GHz and 29 GHz to 34 GHz; electromagnetic waves can be transmitted at the frequency points, so that a wide radiation pattern can be generated; electromagnetic waves are reflected at other frequency points, so that a narrow radiation pattern can be generated; the performance of a Satcom-on-the-move system is greatly improved; the antenna works in a double-frequency mode; the working frequency bands of the antenna are 8-14.5 GHz and 29-34 GHz respectively; and in the two working frequency bands, the radiation patterns of the antenna comprise a narrow-wave beam radiation pattern and a wide-wave beam radiation pattern. The antenna can be well applied to the Satcom-on-the-move antenna system.

Description

technical field [0001] The invention relates to an antenna. Background technique [0002] With the development of satellite communication, mobile communication equipment has extremely important applications in various occasions such as on-site interviews. The so-called mobile communication system is the abbreviation of "moving satellite ground station communication system". Pointing to the direction of the satellite in real time, this process requires a servo system. The mobile communication antenna needs to have a narrow beam width and a large gain, and the Cassegrain antenna is a kind that can well meet its needs. But conventional Cassegrain antennas have a narrow beam across the frequency band, and slight offsets can cause target loss. Contents of the invention [0003] In view of the above prior art, the technical problem to be solved by the present invention is to provide a Cassegrain antenna capable of generating a wider beam width. [0004] In order to solve the...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): H01Q13/02H01Q19/19H01Q15/00H01Q1/50
CPCH01Q1/50H01Q13/02H01Q15/0026H01Q19/19
Inventor 刘可
Owner NANJING UNIV OF AERONAUTICS & ASTRONAUTICS
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com