Patent Application
20080001843
The invention provides an antenna structure with an antenna radome and a method of raising a gain thereof. A dielectric layer formed with metal patterns is utilized such that the antenna radome can be placed in a near-field of a radiating field of the antenna structure. Thus, the beamwidth of the radiating beams of the antenna structure can be converged to increase the gain of the antenna structure.
The antenna radome 120 is made of a metamaterial, and has at least one dielectric layer. In this embodiment, the antenna radome 120 has, without limitation to, three dielectric layers including a dielectric material layer 121, a dielectric material layer 122 and a dielectric material layer 123. The upper surfaces of the dielectric material layers 121 to 123 are formed with multiple S-shaped metal patterns 212 to 218, and the lower surfaces of the dielectric material layers 121 to 123 are formed with multiple inverse S-shaped metal patterns 222 to 228 respectively corresponding to the S-shaped metal patterns 212 to 218. The antenna radome 120 may also be regarded as being composed of multiple array elements 130.
In the antenna radome 120, a gap between the S-shaped metal patterns 212 to 218 ranges from 0.002 to 0.2 times of the wavelength of the resonance frequency of the radiating element 110. A gap between the inverse S-shaped metal patterns 222 to 228 ranges from 0.002 to 0.2 times of the wavelength of the resonance frequency of the radiating element 110. The S-shaped metal patterns 212 to 218 and the inverse S-shaped metal patterns 222 to 228, which are formed on the dielectric material layer 121 by way of printing or etching, have simple structures and may be manufactured using the current printed circuit board (PCB) process. So, the manufacturing cost thereof may be reduced greatly.
The method of the invention for raising a gain of the antenna structure is to attach the antenna radome 120 to the radiating element 110 to converge the radiating beams emitted by the radiating element 110. The antenna radome 120 is placed at a near-field position of an electromagnetic field created by the radiating element 110. The S-shaped metal patterns 212 to 218 are respectively coupled to the corresponding inverse S-shaped metal patterns 222 to 228 to converge the radiating beams outputted from the radiating element 110, so that the beamwidth of the radiating beams is decreased, and the gain of the antenna structure 100 is increased.
The metal patterns on the dielectric material layers 121 to 123 are not restricted to the S-shaped metal patterns and the inverse S-shaped metal patterns in the antenna structure 100 mentioned hereinabove. Any metal pattern having the gap ranging between 0.002 to 0.2 times of the wavelength of the resonance frequency of the radiating element 110 can be used in the antenna structure 100 of this invention as long as the metal patterns formed on the upper and lower surfaces can be coupled to each other. In addition, the dielectric constants and the magnetic coefficients of the dielectric material layers 121 to 123 may be the same as or different from one another in the antenna structure 100. For example, the magnetic coefficients of the dielectric material layer 121 and the dielectric material layer 123 are the same, but are unequal to the magnetic coefficient of the dielectric material layer 122. Alternatively, the magnetic coefficients of the dielectric material layers 121 to 123 may be different from one another. The relationships between the dielectric constants of the dielectric material layers 121 to 123 may also be similar to those of the magnetic coefficients. When the dielectric constants and the magnetic coefficients of the dielectric material layers 121 to 123 are different from one another, the gap between the S-shaped metal patterns and the gap between the inverse S-shaped metal patterns have to be adjusted slightly but still range from 0.002 to 0.2 times of the wavelength of the resonance frequency of the radiating element 110.
According to the antenna structure, the antenna radome and the method of raising the gain of the antenna structure according to the embodiment of the invention, the metal patterns coupled to each other are formed on the dielectric material layer by way of printing or etching, and the antenna radome is placed in the near-field of the radiating field of the antenna structure to converge the beamwidth of the radiating beams outputted from the antenna structure and thus to increase the gain of the antenna structure. The metal patterns have the feature of the simple structure, and can be manufactured using the current PCB manufacturing process so that the manufacturing cost can be greatly reduced. In addition, because the antenna radome is placed in the near-field of the antenna structure, the size of the overall antenna structure can be further minimized, and the utility can be enhanced.
While the invention has been described by way of example and in terms of a preferred embodiment, it is to be understood that the invention is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures.
| Number | Date | Country | Kind |
|---|---|---|---|
| 95123928 | Jun 2006 | TW | national |
