Patent Description:
Among the current Netcom products, an LTE frequency band (a low frequency: <NUM>-<NUM> and a high frequency: <NUM>-<NUM>) of a fourth-generation communication system is commonly used at present. In response to the advent of a fifth-generation communication system, a bandwidth required by LTE has increased significantly, where the low frequency is <NUM>-<NUM>, which has an increase of nearly <NUM>, while an intermediate frequency is <NUM>-<NUM>, and the high frequency is <NUM>-<NUM>, and a bandwidth of the intermediate-high frequency is increased by about <NUM>. The original fourth-generation LTE framework cannot meet the demand for the bandwidth.

Patent literature <CIT> proposes an antenna structure including a metal outer cover and an antenna assembly. The metal outer cover has a bent slit. The antenna assembly is stacked on the metal outer cover and covers a portion of the bent slit. The antenna assembly includes a substrate and an antenna pattern disposed on the substrate. The antenna pattern includes a feed end, a first ground end and a second ground end. In the antenna pattern, a first loop and a second loop are formed from the feed end to the first ground end in two respective paths. A third loop is formed from the feed end to the second ground end. The first loop and the third loop resonate with the bent slit to generate a low frequency band and a portion of a high frequency band. The second loop and the third loop resonate with the bent slit to generate another portion of the high frequency band.

Patent literature <CIT> proposes antenna devices for radio communication devices. The antenna device is adapted for receiving radio signals in a first frequency band and a separate second frequency band. The antenna device includes a half-loop radiating. The first frequency band includes the first harmonic for the half-loop radiating element. The half-loop radiating element includes an inductive loading at a high current section for the third harmonic for the half-loop radiating element, such that the second frequency band includes the third harmonic for the half-loop radiating element.

The invention is directed to an antenna module with multi-band and wideband functions.

The invention is directed to an electronic device using the above antenna module.

The invention provides an antenna module including a feed point, a ground plane, a main radiator and a parasitic radiator. The main radiator includes a first portion, a second portion, and a third portion, where the first portion and the second portion extend from the feed point and meet at an intersection after turning. The third portion at least includes a first section and a second section, the first section of the third portion is connected to the intersection, and the second section is connected to the ground plane. The parasitic radiator is connected to the second section and extends towards the first section of the third portion and keeps a coupling gap away from the first section. A feed signal is configured to branch to go along the first portion and the second portion from the feed point and then merge at the intersection, and then sequentially go along the third portion and the ground plane to excite at a first frequency band and a second frequency band. The feed signal is configured to branch to go along the first portion and the second portion from the feed point and then merge at the intersection, and then sequentially go along a part of the first section of the third portion, the coupling gap, the parasitic radiator, the second section of the third portion, and the ground plane to excite at a third frequency band.

In an embodiment of the invention, the antenna module further includes an extended radiator extending from the third portion to adjust impedance matching of the first frequency band.

In an embodiment of the invention, a length of the first portion is greater than a length of the second portion, and the maximum width of the first portion is less than the maximum width of the second portion.

In an embodiment of the invention, the ground plane includes a first ground portion and a second ground portion separated from each other. The first ground portion is close to the second portion, the second ground portion is connected to the third portion, and the first ground portion and the second ground portion are connected to a system ground plane.

In an embodiment of the invention, the coupling gap is located between the parasitic radiator and the first section of the third portion.

In an embodiment of the invention, a length of the feed signal respectively passing through the first portion and the second portion from the feed point and then meeting at the intersection, and then sequentially passing through the third portion and the ground plane is equivalent to a wavelength of the first frequency band and <NUM> times a wavelength of the second frequency band.

In an embodiment of the invention, a length of the feed signal respectively passing through the first portion and the second portion from the feed point and then meeting at the intersection, and then sequentially passing through a part of the first section of the third portion, the coupling gap, the parasitic radiator, the second section of the third portion, and the ground plane is equivalent to a wavelength of the third frequency band.

In an embodiment of the invention, the first frequency band is between <NUM> and <NUM>, the second frequency band is between <NUM> and <NUM>, and the third frequency band is between <NUM> and <NUM>.

The invention provides an electronic device including a heat dissipation conductor, an insulating housing and the antenna module. The insulating housing covers at least part of the heat dissipation conductor. The antenna module is disposed on the insulating housing, where the insulating housing is located between the main radiator of the antenna module and the heat dissipation conductor, and the ground plane of the antenna module is connected to the heat dissipation conductor.

In an embodiment of the invention, a distance between the main radiator and the heat dissipation conductor is between <NUM> and <NUM>.

Based on the above description, the first portion and the second portion of the main radiator of the antenna module of the invention extend from the feed point and meet at an intersection far away from the feed point, the first section of the third portion is connected to the intersection, and the second portion of the third portion is connected to the ground plane. The parasitic radiator is connected to the second section and extends toward the first section of the third portion and keeps a coupling gap away from the first section. Based on the above design, the feed signal may go along the first portion and the second portion from the feed point and then meet at the intersection, and then sequentially go along the third portion and the ground plane to excite at the first frequency band and the second frequency band. In addition, the feed signal may go along the first portion and the second portion from the feed point and then meet at the intersection, and then sequentially go along a part of the first section of the third portion, the coupling gap, the parasitic radiator, the second section of the third portion, and the ground plane to excite at the third frequency band. Therefore, the antenna module of the invention may have multi-band and wideband effects.

In addition, in the electronic device of the invention, the antenna module is arranged on the insulating housing, and the ground plane of the antenna module is connected to the heat dissipation conductor, so that the heat dissipation conductor serves as the system ground plane. In this way, besides that a ground area is increased, even if the antenna module is quite close to the heat dissipation conductor, the efficiency of the antenna module is not affected, which achieves reduction of an antenna clearance area.

<FIG> is a schematic diagram of an antenna module according to an embodiment of the invention. Referring to <FIG>, the antenna module <NUM> of the embodiment may excite at a first frequency band, a second frequency band, and a third frequency band. The first frequency band is between <NUM> and <NUM>, the second frequency band is between <NUM> and <NUM>, and the third frequency band is between <NUM> and <NUM>. Certainly, the ranges of the first frequency band, the second frequency band, and the third frequency band are not limited thereto. The antenna module <NUM> of the embodiment my meet a full frequency band of Sub-<NUM> of LTE. The antenna module <NUM> is described in detail below.

The antenna module <NUM> of the embodiment may be in the form of a loop antenna. The antenna module <NUM> includes a feed point <NUM>, a ground plane <NUM>, a main radiator <NUM> and a parasitic radiator <NUM>. The main radiator <NUM> includes a first portion <NUM>, a second portion <NUM> and a third portion <NUM>. The first portion <NUM> and the second portion <NUM> of the main radiator <NUM> extend in different directions from the feed point <NUM> and meet at an intersection <NUM> after turning. In the embodiment, the first portion <NUM> and the second portion <NUM> of the main radiator <NUM> form a closed loop, such as a rectangle, but a shape of the closed ring is not limited thereto.

A length of the first portion <NUM> (the length of a path from the feed point <NUM> to the right to the intersection <NUM>) of the main radiator <NUM> is greater than a length of the second portion <NUM> (the length of a path from the feed point <NUM> to the left to the intersection <NUM>). In addition, the maximum width W1 of the first portion <NUM> is less than the maximum width W2 of the second portion <NUM>.

In the embodiment, a feed signal may travel from the feed point <NUM> along two paths, the first portion <NUM> and the second portion <NUM> of the main radiator <NUM> until meeting at the intersection. Therefore, the first portion <NUM> and the second portion <NUM> of the main radiator <NUM> may be used to provide two signal paths, so that the first frequency band may achieve a dual-mode effect.

The third portion <NUM> includes a first section <NUM>, a second section <NUM>, and a third section <NUM> connected to the first section <NUM> and the second section <NUM>. In the embodiment, the first section <NUM>, the third section <NUM>, and the second section <NUM> are connected to each other in a bending manner, and present a pattern close to a U-shape. The first section <NUM> of the third portion <NUM> is connected to the intersection <NUM>, and the second section <NUM> is connected to the ground plane <NUM>.

The parasitic radiator <NUM> is connected to the second section <NUM> and extends toward the first section <NUM>. In the embodiment, a coupling gap I is kept between the parasitic radiator <NUM> and the first section <NUM> of the third portion <NUM>.

In addition, the ground plane <NUM> includes a first ground portion <NUM> and a second ground portion <NUM> separated from each other. The first ground portion <NUM> is close to the second portion <NUM> of the main radiator <NUM>, and the second ground portion <NUM> is connected to the third portion <NUM> of the main radiator <NUM>. The first ground portion <NUM> and the second ground portion <NUM> are connected to a system ground plane <NUM>.

Moreover, the antenna module <NUM> further includes an extended radiator <NUM> that extends from the first section <NUM> of the third portion <NUM> of the main radiator <NUM> to perform impedance matching of the first frequency band to achieve a wideband of <NUM>-<NUM>.

<FIG> is a schematic diagram of a signal path of the antenna module of <FIG> exciting at the first frequency band and the second frequency band. Referring to bold lines in <FIG>, the feed signal may go along the first portion <NUM> and the second portion <NUM> from the feed point <NUM> and then meet at the intersection <NUM>, and then sequentially go along the third portion <NUM>, the second ground portion <NUM> of the ground plane <NUM>, the system ground plane <NUM> and the first ground portion <NUM> of the ground plane <NUM> to form a larger loop excitation path.

In the embodiment, the above path may excite at a first frequency band and a second frequency band. The second frequency band is a frequency multiplication of the first frequency band. Therefore, the length of the feed signal going along the first portion <NUM> and the second portion <NUM> from the feed point <NUM> and then meeting at the intersection <NUM>, and then sequentially going along the third portion <NUM> and the ground plane <NUM> is equivalent to a wavelength of the first frequency band and <NUM> times a wavelength of the second frequency band.

<FIG> is a schematic diagram of a signal path of the antenna module of <FIG> exciting at the third frequency band. Referring to the bold lines in <FIG>, the feed signal may also go along the first portion <NUM> and the second portion <NUM> from the feed point <NUM> and then meet at the intersection <NUM>, and then sequentially go along a part of the first section <NUM> of the third portion <NUM>, the coupling gap I, the parasitic radiator <NUM>, the second section <NUM> of the third portion <NUM>, the second ground portion <NUM> of the ground plane <NUM>, the system ground plane <NUM>, and the first ground portion <NUM> of the ground plane <NUM> to form a smaller loop excitation path.

In the embodiment, the above path can excite at a third frequency band. A length of the feed signal going along the first portion <NUM> and the second portion <NUM> from the feed point <NUM> and then meeting at the intersection <NUM>, and then sequentially going along a part of the first section <NUM> of the third portion <NUM>, the coupling gap I, the parasitic radiator <NUM>, the second section <NUM> of the third portion <NUM>, and the ground plane <NUM> is equivalent to a wavelength of the third frequency band.

Therefore, the antenna module <NUM> of the embodiment extends from the feed point <NUM> via the first portion <NUM> and the second portion <NUM> of the main radiator <NUM> and has the intersection <NUM> far away from the feed point <NUM>. The first section <NUM> of the third portion <NUM> is connected to the intersection <NUM>, and the second section <NUM> of the third portion <NUM> is connected to the ground plane <NUM>. The parasitic radiator <NUM> is connected to the second section <NUM> and extends toward the first section <NUM>, and may meet a full frequency band of Sub-<NUM> of LTE (three bandwidths of a low frequency <NUM>-<NUM>, an intermediate frequency <NUM>-<NUM>, and a high frequency <NUM>-<NUM>).

In the contrast, the conventional antenna cannot achieve such wideband, it needs a switch to switch the frequency bands, or it needs to design an antenna that may resonate at different frequency bands according to regulations of different nations, or it needs to use LC components to adjust impedance matching of the antenna to achieve such a wideband. Since the antenna module <NUM> of the embodiment may reach the full frequency band of Sub-<NUM> of LTE, there is no need to arrange additional components to perform switching, and there is no need to use different antennas by nations, which is very convenient in manufacturing.

<FIG> is a schematic diagram of an electronic device according to an embodiment of the invention. Referring to <FIG>, in the embodiment, the electronic device <NUM> is, for example, a wireless router, but the type of the electronic device <NUM> is not limited thereto. The electronic device <NUM> includes a heat dissipation conductor <NUM>, an insulating housing <NUM> and the antenna module <NUM>. The heat dissipation conductor <NUM> is, for example, metal heat dissipation fins, and the insulating housing <NUM> is, for example, a plastic shell. The insulating housing <NUM> covers at least part of the heat dissipation conductor <NUM>. The antenna module <NUM> is disposed on a circuit board <NUM>, and the circuit board <NUM> is disposed on the insulating housing <NUM>. The ground plane <NUM> of the antenna module <NUM> is connected to the heat dissipation conductor <NUM>.

In the embodiment, the heat dissipation conductor <NUM> is the system ground plane <NUM> (indicated in <FIG>). In the contrast, the conventional antenna requires a sufficient distance from the nearby metal to obtain a sufficient antenna clearance area, so as to prevent the nearby metal from affecting the antenna efficiency, in the embodiment, since the ground plane <NUM> of the antenna module <NUM> is connected to the heat dissipation conductor <NUM>, the heat dissipation conductor <NUM> of the electronic device <NUM> may be used as the system ground plane <NUM> of the antenna. Therefore, the heat dissipation conductor <NUM> does not affect the antenna efficiency of the antenna module <NUM>, and the distance between the antenna module <NUM> and the heat dissipation conductor <NUM> may be reduced. A distance between the main radiator <NUM> (indicated in <FIG>) of the antenna module <NUM> and the heat dissipation conductor <NUM> may be, for example, between <NUM> and <NUM>, or even between <NUM> and <NUM>, which may reduce an overall volume of the electronic device <NUM>.

<FIG> is a plot of frequency vs. return loss of the antenna module of <FIG>. Referring to <FIG>, the return losses of the antenna module <NUM> in the first frequency band, the second frequency band, and the third frequency band may all be lower than -6dB, which achieves a good performance. In addition, through simulation, in the embodiment, the antenna efficiency of the antenna module <NUM> in the first frequency band is between <NUM>% and <NUM>%, the antenna efficiency in the second frequency band is between <NUM>% and <NUM>%, and the antenna efficiency in the third frequency band is between <NUM>% and <NUM>%, which achieves a good performance.

<FIG> are antenna pattern diagrams of the antenna module of <FIG> in an XZ plane, a YZ plane, and an XY plane when the antenna module is in the first frequency band. <FIG> are antenna pattern diagrams of the antenna module of <FIG> in the XZ plane, the YZ plane, and the XY plane when the antenna module is in the second frequency band. <FIG> are antenna pattern diagrams of the antenna module of <FIG> in the XZ plane, the YZ plane and the XY plane when the antenna module is in the third frequency band.

It should be noted that <NUM> is taken as an example in <FIG>, <NUM> is taken as an example in <FIG>, and <NUM> is taken as an example in <FIG>. Referring to <FIG>, <FIG>, and <FIG>, the antenna module <NUM> of the embodiment has good performance in all of the XZ plane, YZ plane, and XY plane in the first frequency band, the second frequency band, and the third frequency band.

In summary, the first portion and the second portion of the main radiator of the antenna module of the invention extend from the feed point and meet at an intersection far away from the feed point, the first section of the third portion is connected to the intersection, and the second portion of the third portion is connected to the ground plane. The parasitic radiator is connected to the second section and extends toward the first section of the third portion. Based on the above design, the feed signal may go along the first portion and the second portion from the feed point and then meet at the intersection, and then sequentially go along the third portion and the ground plane to excite the first frequency band and the second frequency band. In addition, the feed signal may go along the first portion and the second portion from the feed point and then meet at the intersection, and then sequentially go along a part of the first section of the third portion, the coupling gap, the parasitic radiator, the second section of the third portion, and the ground plane to excite the third frequency band. Therefore, the antenna module of the invention may have multi-band and wideband effects.

Claim 1:
An antenna module (<NUM>), comprising:
a feed point (<NUM>);
a ground plane (<NUM>);
a main radiator (<NUM>), comprising a first portion (<NUM>), a second portion (<NUM>), and a third portion (<NUM>), wherein the first portion (<NUM>) and the second portion (<NUM>) extend from the feed point (<NUM>) and meet at an intersection (<NUM>), the third portion (<NUM>) at least comprises a first section (<NUM>) and a second section (<NUM>), the first section (<NUM>) of the third portion (<NUM>) is connected to the intersection (<NUM>), and the second section (<NUM>) is connected to the ground plane (<NUM>); and
a parasitic radiator (<NUM>), connected to the second section (<NUM>) and extending towards the first section (<NUM>) of the third portion (<NUM>) and having a coupling gap (I) away from the first section (<NUM>), wherein a feed signal is configured to branch at the feed point (<NUM>) and go through the first portion (<NUM>) and the second portion (<NUM>) and then merge at the intersection (<NUM>), and then sequentially go along the third portion (<NUM>) and the ground plane (<NUM>) to excite at a first frequency band and a second frequency band, and go along a part of the first section (<NUM>) of the third portion (<NUM>), the coupling gap (I), the parasitic radiator (<NUM>), the second section (<NUM>) of the third portion (<NUM>), and the ground plane (<NUM>) to excite at a third frequency band.