TWI646727B - Mobile device - Google Patents

Abstract

A mobile device includes a metal back cover, a ground plane, a feed portion, a parasitic portion, and a dielectric substrate. The metal back cover has a first slot and a second slot. The ground plane is coupled to the metal back cover. The feeding portion is coupled to a signal source, wherein the feeding portion extends across the first slot and the second slot. The parasitic portion is coupled to the ground plane, wherein the parasitic portion extends across the second slot and adjacent to the feed portion. The ground plane, the feed portion, and the parasitic portion are all disposed on the dielectric substrate. The feeding portion, the parasitic portion, and the first slot and the second slot of the metal back cover together form an antenna structure.

Description

Mobile device

The present invention relates to a mobile device, and more particularly to a mobile device and its antenna structure.

With the development of mobile communication technologies, mobile devices have become more and more popular in recent years, such as portable computers, mobile phones, multimedia players, and other portable electronic devices with mixed functions. In order to meet people's needs, mobile devices usually have the function of wireless communication. Some cover long-range wireless communication range, for example, mobile phones use 2G, 3G, LTE (Long Term Evolution) systems and the 700MHz, 850MHz, 900MHz, 1800MHz, 1900MHz, 2100MHz, 2300MHz and 2500MHz bands used for communication, and Some cover short-range wireless communication ranges, such as Wi-Fi, Bluetooth systems using 2.4GHz, 5.2GHz and 5.8GHz bands for communication.

In order to pursue a beautiful appearance, today's designers often add elements of metal components to mobile devices. However, the added metal components are likely to have a negative impact on the antennas that support wireless communication in mobile devices, thereby reducing the overall communication quality of the mobile device. Therefore, it is necessary to propose a new mobile device and antenna structure to overcome the problems faced by traditional technologies.

In a preferred embodiment, the present invention provides a mobile device package The method includes: a metal back cover having a first slot and a second slot; a grounding surface coupled to the metal back cover; and a feeding portion coupled to a signal source, wherein the feeding portion extends across The first slot and the second slot; a parasitic portion coupled to the ground plane, wherein the parasitic portion extends across the second slot and adjacent to the feed portion; and a dielectric substrate, wherein the connection The ground, the feeding portion, and the parasitic portion are disposed on the dielectric substrate; wherein the feeding portion, the parasitic portion, and the first slot and the second slot of the metal back cover together form an antenna structure .

In some embodiments, the first slot is a closed slot having two closed ends.

In some embodiments, the second slot is an open slot having an open end and a closed end.

In some embodiments, the feed portion is generally T-shaped.

In some embodiments, the parasitic portion is substantially rectangular.

In some embodiments, the antenna structure includes a low frequency band, a first high frequency band, and a second high frequency band, the low frequency band being between about 700 MHz and 960 MHz, the first high frequency band being approximately Between 1700 MHz and 2100 MHz, the second high frequency band is between about 2100 MHz and 2700 MHz.

In some embodiments, the length of the first slot is approximately equal to 0.5 times the wavelength of the first high frequency band.

In some embodiments, the length of the second slot is approximately equal to 0.25 times the wavelength of the low frequency band.

In some embodiments, the feed portion, the parasitic portion, and the The first slot of the metal back cover is excited to generate a fundamental resonant mode to form the first high frequency band.

In some embodiments, the feeding portion and the second slot of the metal back cover are excited to generate a fundamental resonant mode to form the low frequency band, and wherein the feeding portion and the second portion of the metal back cover The slots are more excited to produce a higher order resonant mode to form the second high frequency band.

100, 400‧‧‧ mobile devices

110‧‧‧Metal back cover

111‧‧‧The edge of the metal back cover

120‧‧‧first slot

121, 122‧‧‧ Closed end of the first slot

130‧‧‧Second slot

131‧‧‧Open end of the second slot

132‧‧‧Closed end of the second slot

140‧‧‧ Ground plane

150‧‧‧Feeding Department

151‧‧The first branch of the feeding department

152‧‧‧Second Road of the Feeding Department

153‧‧‧ Connection section of the feeding department

160‧‧‧ Parasitic

170‧‧‧Media substrate

190‧‧‧Signal source

401‧‧‧ first position

402‧‧‧The edge of the upper cover

403‧‧‧second position

404‧‧‧The hinge of the notebook computer

410‧‧‧Note computer cover

D1, D2, D3‧‧‧ spacing

The first surface of the E1‧‧• dielectric substrate

E2‧‧‧ second surface of the dielectric substrate

FBL‧‧‧Low frequency band

FBH1‧‧‧ first high frequency band

FBH2‧‧‧second high frequency band

L1, L2, L3, L4, L5‧‧‧ length

W1, W2, W5‧‧‧ width

1A is a perspective view showing a mobile device according to an embodiment of the present invention; FIG. 1B is a schematic view showing a lower portion of a mobile device according to an embodiment of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1D is a cross-sectional view showing a mobile device according to an embodiment of the present invention; FIG. 2 is a cross-sectional view showing a mobile device according to an embodiment of the present invention; Return loss map of the antenna structure of the mobile device; FIG. 3 is a diagram showing an antenna efficiency diagram of the antenna structure of the mobile device according to an embodiment of the present invention; and FIG. 4 is a view showing an action according to an embodiment of the present invention Schematic diagram of the device.

In order to make the objects, features and advantages of the present invention more apparent, Specific embodiments of the invention are set forth below, and in conjunction with the drawings, the detailed description below.

Certain terms are used throughout the description and claims to refer to particular elements. Those skilled in the art will appreciate that a hardware manufacturer may refer to the same component by a different noun. The scope of the present specification and the patent application do not use the difference in the name as the means for distinguishing the elements, but the difference in function of the elements as the criterion for distinguishing. The words "including" and "including" as used throughout the specification and patent application are open-ended terms and should be interpreted as "including but not limited to". The term "substantially" means that within the acceptable error range, those skilled in the art will be able to solve the technical problems within a certain error range to achieve the basic technical effects. In addition, the term "coupled" is used in this specification to include any direct and indirect electrical connection means. Therefore, if a first device is coupled to a second device, the first device can be directly electrically connected to the second device, or indirectly connected to the second device via other devices or connection means. Two devices.

1A is a perspective view showing a mobile device 100 according to an embodiment of the present invention. FIG. 1B is a schematic diagram showing a lower portion of a mobile device 100 according to an embodiment of the invention. FIG. 1C is a schematic diagram showing an upper portion of a mobile device 100 according to an embodiment of the invention. 1D is a cross-sectional view showing a mobile device 100 in accordance with an embodiment of the present invention. Please refer to Figures 1A, 1B, 1C, and 1D together. The mobile device 100 can be a smart phone, a tablet computer, or a notebook computer. In the embodiment of the 1A, 1B, 1C, and 1D diagrams, the mobile device 100 includes: a metal back cover 110, a A ground plane 140, a feeding element 150, a parasitic element 160, and a dielectric substrate 170. It should be understood that although not shown in the 1A, 1B, 1C, and 1D drawings, the mobile device 100 may further include other components, such as a processor and a touch control panel. , a speaker, a battery module, and a housing.

The metal back cover 110 has a first slot (S1) 120 and a second slot 130, wherein the first slot 120 and the second slot 130 are respectively substantially straight, and the first slot 120 and the first slot The two slots 130 may be substantially parallel to each other. In detail, the first slot 120 is a closed slot, which has two closed ends 121 and 122 away from each other; and the second slot 130 is an open slot (Open Slot). It has one open end 131 and one closed end 132 away from each other. However, the invention is not limited to this. In other embodiments, the first slot 120 and the second slot 130 may be closed slots, or both the first slot 120 and the second slot 130 may be open slots.

The ground plane 140, the feed portion 150, and the parasitic portion 160 are all made of a metal material such as copper, silver, aluminum, iron, or an alloy thereof. The dielectric substrate 170 can be a FR4 (Flame Retardant 4) substrate or a Flexible Printed Circuit Board (FPCB). The dielectric substrate 170 may have a first surface E1 and a second surface E2, wherein the ground plane 140, the feeding portion 150, and the parasitic portion 160 are disposed on the first surface E1 of the dielectric substrate 170, and the dielectric substrate 170 The second surface E2 can be attached to or directly attached to the metal back cover 110 (adjacent or contacting the first slot 120 and the second slot 130).

The ground plane 140 is coupled to the metal back cover 110, which provides a ground potential for the mobile device 100. For example, the ground plane 140 can be a ground copper foil that can extend from the dielectric substrate 170 to the metal back cover 110. The feed unit 150 is coupled to a signal source 190. The signal source 190 can be a radio frequency (RF) module that can be used to generate a transmit signal or process a receive signal. The feed portion 150 extends across the first slot 120 and the second slot 130 of the metal back cover 110. For example, a vertical projection of the feed portion 150 on the metal back cover 110 may span the entire width W1 of the first slot 120 and may span at least two-thirds of the width W2 of the second slot 130. The parasitic portion 160 is coupled to the ground plane 140 , wherein the parasitic portion 160 extends across the second slot 130 of the metal back cover 110 and adjacent to the feed portion 150 . For example, a vertical projection of the parasitic portion 160 on one of the metal back covers 110 may span the entire width W2 of the second slot 130 and may be adjacent to the edge of the first slot 120.

The feed portion 150 may be substantially in a T shape. In detail, the feeding portion 150 includes a first branch 151, a second branch 152, and a connecting branch 153, wherein the first branch 151 and the second branch 152 of the feeding portion 150 can be substantially The opposite direction is extended. The signal source 190 can be coupled to the first branch 151 via the connection branch 153, and the signal source 190 can be coupled to the second branch 152 via the connection branch 153. The parasitic portion 160 can be substantially a rectangle. The parasitic portion 160 is adjacent to the first branch 151 of the feeding portion 150 such that a coupling gap (Coupling Gap) can be formed between the parasitic portion 160 and the feeding portion 150, and the parasitic portion 160 can be coupled and excited by the feeding portion 150. In the preferred embodiment, the feed portion 150, the parasitic portion 160, and the first slot 120 and the second slot 130 of the metal back cover 110 together form an antenna structure.

2 is a diagram showing a Return Loss diagram of an antenna structure of a mobile device 100 according to an embodiment of the present invention, wherein the horizontal axis represents the operating frequency (MHz) and the vertical axis represents the return loss (dB). According to the measurement result of FIG. 2, when receiving or transmitting a wireless signal, the antenna structure of the mobile device 100 can cover a low frequency band FBL, a first high frequency band FBH1, and a second high frequency band FBH2, wherein the low frequency band The FBL may be between about 700 MHz and 960 MHz, the first high frequency band FBH1 may be between about 1700 MHz and 2100 MHz, and the second high frequency band FBH2 may be between about 2100 MHz and 2700 MHz. Therefore, the antenna structure of the mobile device 100 can support at least LTE (Long Term Evolution) wideband band operation in the US and European specifications.

In some embodiments, the principle of operation of the antenna structure of mobile device 100 can be as follows. The feeding portion 150 and the second slot 130 of the metal back cover 110 are excited to generate a fundamental resonant mode to form the aforementioned low frequency band FBL. The first branch 151 of the feed portion 150, the parasitic portion 160, and the first slot 120 of the metal back cover 110 are excited to generate another fundamental frequency resonant mode to form the aforementioned first high frequency band FBH1. The feeding portion 150 and the second slot 130 of the metal back cover 110 are further excited to generate a high-order Resonant Mode (triple frequency) to form the aforementioned second high frequency band FBH2. Since the low frequency band FBL, the first high frequency band FBH1, and the second high frequency band FBH2 at least partially share the same resonant path, the design will effectively reduce the overall area of the antenna structure of the mobile device 100.

In some embodiments, the component dimensions of the mobile device 100 can be as described below. The length L1 of the first slot 120 may be greater than or equal to the length L2 of the second slot 130. In detail, the length L1 of the first slot 120 is substantially equal to the first 0.5 times the wavelength (λ/2) of the high frequency band FBH1. The width W1 of the first slot 120 is between about 2 mm and 3 mm. The length L2 of the second slot 130 is approximately equal to 0.25 times the wavelength (λ/4) of the low frequency band FBL. The width W2 of the second slot 130 is between about 2 mm and 3 mm. The distance D1 between the first slot 120 and one of the edges 111 of the metal back cover 110 is about 4 mm. The distance D2 between the second slot 130 and the edge 111 of the metal back cover 110 is between about 7 mm and 7.5 mm. The distance D3 between the first slot 120 and the second slot 130 is between about 2 mm and 3 mm. The length L3 of the first branch 151 of the feed portion 150 is substantially equal to 0.25 times the wavelength (λ/4) of the second high frequency band FBH2. The length L4 of the second branch 152 of the feed portion 150 is also substantially equal to 0.25 times the wavelength (λ/4) of the second high frequency band FBH2. The length L5 of the parasitic portion 160 is about 6 mm. The width W5 of the parasitic portion 160 is about 4 mm. The above component size range is determined based on a plurality of experimental results, which contributes to optimizing the operating frequency band and Impedance Matching of the antenna structure of the mobile device 100.

3 is a diagram showing an antenna efficiency of an antenna structure of a mobile device 100 according to an embodiment of the present invention, wherein the horizontal axis represents the operating frequency (MHz) and the vertical axis represents the antenna efficiency (dB). According to the measurement result of FIG. 3, the antenna structure of the mobile device 100 has an antenna efficiency of about -1.5 dB in the low frequency band FBL, and the antenna efficiency in the first high frequency band FBH1 and the second high frequency band FBH2 is about Up to -3dB, which can meet the practical application requirements of general mobile communication devices.

Figure 4 is a schematic diagram showing a mobile device 400 in accordance with an embodiment of the present invention. In the embodiment of FIG. 4, the mobile device 400 is a notebook computer, and the metal back cover 110 can be a cover case 410 of the notebook computer (commonly referred to as "A" in the notebook computer). If the aforementioned antenna structure is implemented In the notebook computer, the first slot 120 and the second slot 130 may be adjacent to an edge 402 of the upper cover housing 410 (eg, may be formed at a first position 401) or adjacent to one of the notebook computers. The hinge (Hinge) 404 (i.e., may be formed at a second position 403). Whether the aforementioned antenna structure is located at the first location 401 or the second location 403 on the upper cover housing 410, it can cover the wideband operating band of LTE and can provide sufficient antenna efficiency.

The present invention provides a novel antenna structure that includes the design of a dual slot. When the antenna structure is applied to a mobile device having a metal back cover, since the metal back cover can be regarded as an extension of the antenna structure, the metal back cover can be effectively prevented from adversely affecting the communication quality of the mobile device. It should also be noted that the present invention can further improve the design of the mobile device without using any antenna window (Antenna Window) on the metal back cover. In summary, the present invention has the advantages of small size, wide frequency band, and beautification of the appearance of the device, so it is well suited for use in a variety of various types of mobile communication devices.

It is to be noted that the above-described component sizes, component shapes, and frequency ranges are not limitations of the present invention. The antenna designer can adjust these settings according to different needs. The mobile device and antenna structure of the present invention are not limited to the state illustrated in Figures 1-4. The invention may include only any one or more of the features of any one or a plurality of embodiments of Figures 1-4. In other words, not all illustrated features must be implemented simultaneously in the mobile device and antenna structure of the present invention.

The ordinal numbers in this specification and the scope of the patent application, such as "first", "second", "third", etc., have no sequential relationship with each other, and are only used to indicate that two are identical. Different components of the name.

The present invention has been described above with reference to the preferred embodiments thereof, and is not intended to limit the scope of the present invention, and the invention may be modified and modified without departing from the spirit and scope of the invention. The scope of the invention is defined by the scope of the appended claims.

Claims (9)

A mobile device includes: a metal back cover having a first slot and a second slot; a ground plane coupled to the metal back cover; and a feed portion coupled to a signal source, wherein the feed The entry portion extends across the first slot and the second slot; a parasitic portion coupled to the ground plane, wherein the parasitic portion extends across the second slot and adjacent to the feed portion; and a dielectric substrate The grounding surface, the feeding portion, and the parasitic portion are all disposed on the dielectric substrate; wherein the feeding portion, the parasitic portion, and the first slot of the metal back cover are common to the second slot Forming an antenna structure; wherein the first slot is a closed slot having two closed ends. The mobile device of claim 1, wherein the second slot is an open slot having an open end and a closed end. The mobile device of claim 1, wherein the feeding portion is substantially T-shaped. The mobile device of claim 1, wherein the parasitic portion is substantially rectangular. The mobile device of claim 1, wherein the antenna structure comprises a low frequency band, a first high frequency band, and a second high frequency band, the low frequency band being between 700 MHz and 960 MHz, The first high frequency band is between about 1700 MHz and 2100 MHz, and the second high frequency band is between about 2100 MHz and 2700 MHz. The mobile device of claim 5, wherein the length of the first slot is substantially equal to 0.5 times the wavelength of the first high frequency band. The mobile device of claim 5, wherein the second slot has a length substantially equal to 0.25 times the wavelength of the low frequency band. The mobile device of claim 5, wherein the feeding portion, the parasitic portion, and the first slot of the metal back cover are excited to generate a fundamental resonant mode to form the first high frequency. frequency band. The mobile device of claim 5, wherein the feeding portion and the second slot of the metal back cover are excited to generate a fundamental resonant mode to form the low frequency band, wherein the feeding portion and The second slot of the metal back cover is further excited to generate a higher order resonant mode to form the second high frequency band.