1. Field of the Invention
The present invention relates to an antenna for notebook computer and more particularly, to a multi-band antenna that has capacitor/inductor means built therein for impedance matching adjustment.
2. Description of the Related Art
Following fast development of wireless communication technology, mobile electronic apparatus must be equipped with a multi-band antenna for working at different frequencies. It is the mainstream to use a multi-band metal planar antenna in a cell phone or notebook computer for receiving or transmitting radio signals.
Conventionally, a metal planar antenna is connected to a circuit board in a mobile electronic apparatus through a SMT (Surface Mount Technology) component. Regular SMT components are designed having fixed impedance standards so that a matching antenna requires a matching circuit to regulate capacitance and inductance values. Using an antenna with a matching circuit complicates the design of the antenna and limiting the bandwidth and efficiency of the antenna. An improvement in this regard is necessary.
Accordingly, there is a strong need to provide an antenna structure that has a small size and allows adjustment of the working frequency to achieve impedance matching.
The present invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide a multi-band antenna for notebook computer that has a small size and is practical for working at different frequencies. It is another object of the present invention to provide a multi-band antenna for notebook computer that has capacitor/inductor means for optimal matching adjustment.
To achieve these and other objects of the present invention, a multi-band antenna comprises an insulative carrier board arranged on the top side of the display screen of a notebook computer, a main antenna which has the top metal strip thereof disposed at the top edge of the insulative carrier board and the grounding metal strip thereon arranged on the insulative carrier board, an inverted L antenna arranged on the insulative carrier board, a first capacitor, a second capacitor, and an antenna feed-in terminal and/or an inductor arranged on the insulative carrier board and set between the inverted L antenna and the main antenna to achieve optimal matching subject to adjustment of the capacitance values of the first and second capacitors and the inductance value and position of the inductor.
Referring to
Referring to
The inverted L antenna 13 is also arranged on the electrically insulative carrier board 11, having the transverse axis 131 thereof disposed at one lateral side relative to the transverse axis 1222B of the L-shaped body portion 1222 of the grounding metal strip 122 of the main antenna 12 at one lateral side and the longitudinal axis 132 thereof kept in parallel to the top metal strip 121 of the main antenna 12.
The first capacitor 14 is electrically connected between the transverse axis 131 of the inverted L antenna 13 and the transverse axis 1222B of the L-shaped body portion 1222 of the grounding metal strip 122 of the main antenna 12. The second capacitor 15 is electrically connected between the distal end of the transverse axis 1222B of the L-shaped body portion 1222 of the grounding metal strip 122 of the main antenna 12 and the transverse axis 131 of the grounding portion 1224 of the grounding metal strip 122 of the main antenna 12. The antenna feed-in terminal 16 is located on the distal end of the transverse axis 131 of the inverted L antenna 13.
During operation of the multi-band antenna 1, a radio signal is inputted through the antenna feed-in terminal 16 into the inverted L antenna 13 and then transferred by the first capacitor 14 to the distal end of the longitudinal axis 1222A of the L-shaped body portion 1222 of the grounding metal strip 122 of the main antenna 12.
It is to be understood that the first capacitor 14 and the second antenna 15 can match the antenna. Further, the position of the first capacitor 14 is vertically adjustable to match the multi-band antenna 1.
Further, in the multi-band antenna 1, the connection between the top end of the curved portion 1223 of the grounding metal strip 122 of the main antenna 12 and the longitudinal axis 1222A of the L-shaped body portion 1222 is movable to match the multi-band antenna 1 for inductance grounding.
Further, by means of adjusting the capacitance values and positions of the first capacitor 14 and second capacitor and the connection location between the top end of the curved portion 1223 and the longitudinal axis 1222A of the L-shaped body portion 1222, optimal matching of the multi-band antenna 1 is achieved.
Referring to
The inverted L antenna 23 is also arranged on the electrically insulative carrier board 21, having the transverse axis 231 thereof disposed at one lateral side relative to the transverse axis 2222B of the L-shaped body portion 2222 of the grounding metal strip 222 of the main antenna 22 at one lateral side and the longitudinal axis 232 thereof kept in parallel to the top metal strip 221 of the main antenna 22.
The first capacitor 24 is electrically connected between the transverse axis 231 of the inverted L antenna 23 and the transverse axis 2222B of the L-shaped body portion 2222 of the grounding metal strip 222 of the main antenna 22. The second capacitor 25 is electrically connected between the longitudinal axis 2222A of the L-shaped body portion 2222 of the grounding metal strip 222 of the main antenna 22 and the grounding portion 2224 of the grounding metal strip 222 of the main antenna 22. Further, the antenna feed-in terminal 26 is located on the distal end of the transverse axis 231 of the inverted L antenna 23. Further, the inductor 27 is electrically connected between the distal end of the transverse axis 231 of the inverted L antenna 23 and the grounding portion 2224 of the grounding metal strip 222 of the main antenna 22.
During operation of the multi-band antenna 2, a radio signal is inputted through the antenna feed-in terminal 26 into the inverted L antenna 23 and then transferred by the first capacitor 24 to the distal end of the longitudinal axis 2222A of the L-shaped body portion 2222 of the grounding metal strip 222 of the main antenna 22.
Further, in the multi-band antenna 2, the second capacitor 25 can be moved between the longitudinal axis 2222A of the L-shaped body portion 2222 of the grounding metal strip 222 and the grounding portion 2224 to find the best position for optimal matching with the multi-band antenna 2.
Further, in the multi-band antenna 2, the capacitance values and positions of the first capacitor 24 and second capacitor 25 and the inductance value of the inductor 27 are adjustable to achieve optimal matching with the multi-band antenna 2.
1. 700 MHz˜960 MHz.
2. 1710 MHz˜2170 MHz.
3. 2500 MHz˜2700 MHz.
Further, the size of the multi-band antenna 2 in accordance with the second embodiment is about 10 mm shorter than the multi-band antenna 2 in accordance with the first embodiment.
The electrically insulative carrier board 11 or 21 can be made in any configuration for antenna fixation. The shape and type of the electrically insulative carrier board 11 or 21 are similar to those commonly known. No further illustration in this regard is necessary.
Referring to -shaped grounding portion 3223 connected to the display screen 9 and grounded. The distal end of the narrow elongated body portion 3222 is connected to the reversely disposed
-shaped grounding portion 3223 by the variable component 35. The display screen 9 serves as a grounding plane.
The inverted L antenna 33 is also arranged on the electrically insulative carrier board 31, having the transverse axis 331 thereof disposed at one lateral side of the distal end of the narrow elongated body portion 3222 and the longitudinal axis 332 thereof disposed in parallel to the top metal strip 321.
The first capacitor 34 is electrically connected between the transverse axis 331 of the inverted L antenna 33 and the distal end of the narrow elongated body portion 3222. The variable component 35 is electrically connected between the distal end of the narrow elongated body portion 3222 and the reversely disposed -shaped grounding portion 3223. Further, the antenna feed-in terminal 36 is located on the distal end of the transverse axis 331 of the inverted L antenna 33.
During operation of the multi-band antenna 3, a radio signal is inputted through the antenna feed-in terminal 36 into the inverted L antenna 33 and then transferred by the first capacitor 34 to the distal end of the narrow elongated body portion 3222 of the grounding metal strip 322 of the main antenna 32. The first capacitor 34 and the variable component 35 can match the multi-band antenna 3. The variable component 35 is adapted to adjust the resonant point. Further, the variable component 35 can be a variable inductor or variable capacitor.
Further, in the multi-band antenna 3, the variable component 35 can be moved leftwards or rightwards between the narrow elongated body portion 3222 of the grounding metal strip 322 and the reversely disposed -shaped grounding portion 3223 to adjust the impedance matching of the antenna. Using a different first capacitor 34 having a different capacitance value can achieve the same effect. By means of utilizing the variable characteristic of the variable component 35, the resonant point of the multi-band antenna is adjustable.
In conclusion, the invention has capacitor/inductor means built in the multi-band antenna so that antenna matching can be achieved by means of adjusting the value and position of the capacitor/inductor means without an extra matching circuit, and antenna dimension can be greatly reduced.
Although particular embodiments of the invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.