Patent Application
20080278378
1. Field of the Invention
The invention relates to an antenna, and more particularly to a wideband dielectric resonator antenna.
2. Description of the Related Art
The sizes of conventional dielectric resonator antennas can be reduced by using grounded metal plates at the cost of bandwidth reduction. Conventionally, resonators with different shapes (for example, resonators with a triangular and circular cross section) are stacked to increase bandwidth of dielectric resonator antennas. Or, resonators which transmit signals in different bands are incorporated into one dielectric resonator antenna to provide an increased bandwidth. However, conventional dielectric resonator antennas require a complex manufacturing process and increased cost, and size thereof is large, thus preventing utilization in minimized portable electronic devices.
A detailed description is given in the following embodiments with reference to the accompanying drawings.
The embodiment relates to an antenna comprising a substrate, a feed conductor, a ground layer, a resonator and a short-circuited element. The substrate comprises a first surface and a second surface. The feed conductor is formed on the first surface. The ground layer is formed on the second surface, comprising an aperture. The resonator is disposed on the ground layer, comprising a body and a notch, the notch is formed on a first side of the body, wherein the first side is perpendicular to the ground layer. The short-circuited element is disposed on the first side connecting the ground layer.
The resonator is a dielectric resonator. The dielectric resonator comprises the notch. Therefore, when electric lines pass the notch to the short-circuited element, the electric field thereof is amplified for several times and can be radiated more efficiently. Hence, the quality factors of the resonator are reduced, and bandwidth of the antenna is increased. The antenna is minimized, is easily manufactured, reduces attrition rate and cost, has wide bandwidth of linear polarization, and can be mass produced by a manufacturing process (for example, a low temperature co-fired ceramic process).
The invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:
a and 4b show dimensions of the elements of the antenna.
The following description is of the best-contemplated mode of carrying out the invention. This description is made for the purpose of illustrating the general principles of the invention and should not be taken in a limiting sense. The scope of the invention is best determined by reference to the appended claims.
The feed conductor 120 is longitudinal, extending on a first axis z. The aperture 131 is also longitudinal, extending on a second axis y. The first axis z is perpendicular to the second axis y. The feed conductor 120 extends over and passes the center of the aperture 131 (reference to
The body 141 and the notch 142 are cubical. The first axis z is parallel to the major axis of the body 141. The body 141 overlaps the aperture 131. The body 141 defines a contact area Ac on the ground layer 130. The first axis z passes the center of the contact area Ac, and extends perpendicular to the first side 143.
The resonator 140 is a dielectric resonator made of one of dielectric materials including low temperature co-fired ceramic and materials with high dielectric coefficients. The substrate 110 is made of one of dielectric materials including Teflon, glass fiber, aluminum oxide, ceramic material, FR4 and Duroid. The short-circuited element 150 is a metal sheet.
With reference to
In the embodiment, the dimensions of the body 141 and the notch 142 are a=14.1 mm, b=10.4 mm, d=4.35 mm, s1=4.4 mm, and s2=5.6 mm. The dimension of the aperture 131 is Wa=1.5 mm, and La=7 mm. The dimensions of the substrate 110 and the ground layer 130 are Wg=Lg=60 mm. The thickness of the substrate 110 is t=0.6 mm. Dielectric coefficient of the substrate 110 is 4.4. Dielectric coefficient of the resonator 141 is 20. Edge of the resonator 140 is separated by a distance ds=1.5 mm from the aperture 131. The feed conductor 120 extends over the aperture 131 with length Ls=1.4 mm.
In the embodiment, the dimension of the body (length a, width b and height d) can be modified to modulate the transmission frequency of the antenna. The dimension of the notch 142 (length s1 and width s2) can be modified to fine-tune the transmission frequency and increase a transmission bandwidth of the antenna. Additionally, input impedance between the resonator 140 and the feed conductor 120 can be matched by modifying the dimensions and the positions of the aperture 131 and the feed conductor 120.
While the invention has been described by way of example and in terms of preferred embodiment, it is to be understood that the invention is not limited thereto. To the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.
| Number | Date | Country | Kind |
|---|---|---|---|
| 96116083 | May 2007 | TW | national |
