1. Field of the Invention
The present invention relates to a portable electronic device and an antenna thereof, and more particularly, to a multi-frequency antenna and a portable electronic device applied with the same.
2. Description of the Related Art
With the evolution of wireless communication technology, various portable devices are exploiting wireless communication technology for data transmission, thus causing the antenna design to evolve at a rapid rate. Nowadays, these portable communication devices are becoming lighter and smaller, and the antenna must also be reduced in size in order to be installed into these electronic devices.
In terms of antenna's exterior design, the lengthy external antenna which is designed to receive and transmit radio frequency has become shorter and has been internalized, and it makes the appearance of the devices more appealing. In terms of application aspect, antenna is able to take on different shapes and sizes, thus the antennas can be designed accordingly to comply with various electronic appliance standards and to cater for different system products. Therefore, antenna manufacturing has the characteristic of high variety with low volume. However, the basic objective of designing an antenna is to improve the quality of signal transmission and reception, thus this property should not be compromised from improving its exterior appearance, size or choice of material.
Nowadays, the helical antenna and the monopole antenna are used in the circuit separately, and its pitfall is that both the helical antenna and the monopole antenna can only have a single-band frequency respectively. Although US patent publication number 2006/0050009A1 (claiming priority of TW Appln No.: 093127158) has disclosed a method of combining the application of a helical antenna and a monopole antenna, this application have both antennas fed into a positive current, that is, both antennas are fed into the feeding point and are connected to the same signal wire. Although this method allows the antenna to possess the characteristic of multi-band, it has limited bandwidth because it is not grounded and is still remained in the single resonance mode.
In order to cater for the aforementioned needs in the precedent technology, the present invention provides a portable electronic device with an antenna which can be used for the transmission and reception of radio frequency (RF) signals. The portable electronic devices can be devices such as notebook computers (laptops), personal digital assistants (PDAs), or cellular phones. The portable electronic device comprises an RF signal module and an antenna, wherein the antenna and the RF signal modules are electrically connected. For example, the antenna can be electrically connected to the RF signal module through a signal cable (RF signal cable).
The antenna comprises a helix element, a radiating element and a base. The base comprises a grounding portion and a feeding portion that are electronically separated. For example, a first dielectric element can be installed between the feeding portion and the grounding portion, and the first dielectric element can be formed by dielectric material comprising sponge, acrylic fiber, plastic, or ceramic. The radiating element connecting to the feeding portion is disposed within the helix element. The helix element is connected to the ground.
In one embodiment, the present invention comprises a signal wire passing through the feeding portion of the base and connecting to the radiating element.
In a preferred embodiment, the antenna of the present invention further comprises a second dielectric element, which is disposed between the helix element and the radiating element. The second dielectric element is used to separate the helix element and the radiating element and is used to stabilize their position. The second dielectric element is formed by low dielectric material comprising such as sponge, acrylic fiber, plastic, or ceramic.
Furthermore, the antenna of the present invention can further comprise a third dielectric element, which covers at least a portion of the helix element so as to form the most outer part of the antenna. The material of the third dielectric element can be formed by low dielectric material comprising sponge, acrylic fiber, plastic, or ceramic.
The helix element of the present invention can be designed into different shapes according to the different fields or bandwidths. For example, the helix element can be strip-shaped, or the cross sectional area can be circular, square, oval, triangular, polyhedron or other shapes alike. The length of the helix element is substantially around ¼ λ (wavelength) of low frequency such as 2.4 GHz, for example. The length is calculated by stretching the helix element and measuring it from the grounding portion to its end.
Similarly, the radiating element can also take on different shapes according to the different configuration; for example, the overall shape can substantially be a straight line, cone shape, strip shape, helix shape, or other shapes alike. When the radiating element is strip-shaped, the strip can also take on other forms such as a square, triangular, or an oval shape. The length of the radiating element is substantially around ¼ λ (wavelength) of high frequency such as 5 GHz, for example. The length of the radiating element is calculated by stretching the radiating element and measuring it from the feeding portion.
Furthermore, the present invention can further comprise a load element to enhance the effect of the antenna. The load element is located either on the end of the helix element or on the end of the radiating element.
Moreover, the helix element of the present invention is a parasitical part of the grounding portion. Using the resonance frequency (e.g. high frequency) of the parasitical radiating element to radiate helix element by coupling energy is able to generate another form of resonance frequency (e.g. low frequency). Therefore, the radiated mode can provide a wide frequency band for different system. Various frequencies can be generated through this kind of antenna to cover a wide range of bandwidths for the system requirements. This antenna of the present invention has high practical industrial value as it is simple to design and it also leads to low manufacturing cost.
The advantages and innovative features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
Refer to
Alternatively, in another embodiment, the base 13 need not be a multi-layered circuit board. A first dielectric element 133 can be disposed between the feeding portion 132 and the grounding portion 131. The first dielectric element 133 is formed by the low dielectric material comprising, for example, sponge, acrylic fiber, plastic, or ceramic, such that the feeding portion 132 and the grounding portion 131 are electrically separated.
The radiating element 12 is connected to the feeding portion 132, and is disposed within the helix element 11. The helix element 11 is connected to the grounding portion 131. For example, the radiating element 12 may generate a high resonance frequency (e.g. 5 GHz) and the helix element 11 may generate a low resonance frequency (e.g. 2.4 GHz).
Refer to FIG 1B, which is a diagram showing the average gain in the x-y plane for the embodiment in accordance with
Refer to
Furthermore, the base 13 or 13a can be folded into various shapes to comply with other physical devices that it is to be installed (for example a laptop). Alternatively, the antenna 1 or 1a can simply be glued onto other devices by applying adhesives to the surface of the base 13 or 13a.
Refer to
Moreover, the antenna 1b may further comprise a third dielectric element 15, and the third dielectric element 15 disposed at the outer of antenna 1b can cover at least a portion of the helix element 11. The third dielectric element 15 is formed by low dielectric material such as sponge, acrylic fiber, plastic, ceramic, or the like.
Refer to
Referring to
In one embodiment of the present invention, the helix element 11a can be strip-shaped as shown in
Furthermore, the helix element of the present invention can be strip-shaped as shown in
Similarly, the radiating element can also take on different shapes according to different requirements, for example, the overall shape can substantially be a straight line (as shown in
Refer to
Refer to
In summary, the helix element of the present invention is a parasitical part of the grounding portion. Using the resonance frequency (e.g. high frequency) of the parasitical radiating element to radiate helix element by coupling energy is able to generate another form of resonance frequency (e.g. low frequency). Therefore, the radiated mode can provide a wide frequency band for different system. Various frequencies can be generated through this kind of antenna to cover a wide range of bandwidths for the system requirements. The antenna of the present invention has high practical industrial value as it is simple to design and it also leads to low manufacturing cost.
Refer to
In order to simplify the discussion, the antenna 1 will be used to represent other antennas for below description. The antenna 1 and the RF signal modules 20 can be electrically connected through the signal wire 20 (such as a RF cable). Each portable electronic device 9a, 9b or 9c carries an antenna 1, thus transmission and reception of wireless signals can be performed through the antenna 1. The antenna 1 does not have to be implemented at the position as shown in
It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.
Number | Date | Country | Kind |
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095141199 | Nov 2006 | TW | national |