[0001] The present invention relates to an antenna module according to the pre-characterizing
clause of claim 1.
[0002] Manufacturers are enthusiastic about integrating Worldwide Interoperability for Microwave
Access (WiMAX) and Wireless Fidelity (WiFi). For example, utilizing WiMAX to connect
the broadband networks in buildings located within the coverage of WiMAX base stations,
and providing wireless surfing functions inside the buildings utilizing WiFi can reduce
district limitation and increase wireless transmission efficiency. In this application,
the communication devices (e.g. modems) utilized by the users must be able to communicate
signals with the WiMAX base station and transmit/receive WiFi signals in the buildings
at the same time. However, WiMAX and WiFi bands are so close (WiMAX is 2.3-2.4GHz,
2.5-2.7GHz or 3.5-3.7GHz, while WiFi is 2.4GHz) that the conventional method of selecting
a receiving bandwidth by properly designing the length of the antenna cannot help
the modem to distinguish WiMAX signals from WiFi signals. Additionally, the strength
of a WiFi signal is usually much larger than a WiMAX signal received from the base
station since the WiFi signal is transmitted over a shorter distance. Therefore, when
the modem processes a WiMAX signal and a WiFi signal at the same time, the WiFi signal
may interfere with the WiMAX signal, thereby influence the communication quality.
[0003] Furthermore, there are other wireless signals, such as Bluetooth signals that use
a 2.4GHz-2.483GHz band, and 3G signals that use 1885-1980MHz, 2010-2025MHz or 2110-2170MHz
bands. Meanwhile, GSM signals use 900MHz, 1800MHz and 1900MHz bands. As can be seen
from the above data, the bands of these wireless communication signals are very close.
That is, if multiple systems are integrated in a same module or a same chip, there
will be interference among the signals.
[0004] This in mind, the present invention aims at providing an antenna module that solves
the aforementioned interference problems.
[0005] This is achieved by an antenna module according to claim 1. The dependent claims
pertain to corresponding further developments and improvements.
[0006] As will be seen more clearly from the detailed description following below, the claimed
antenna module includes a shielding portion, disposed between at least a first antenna
and at least a second antenna.
[0007] In the following, the invention is further illustrated by way of example, taking
reference to the accompanying drawings. Thereof
Fig. 1 is a diagram of an antenna module according to an exemplary embodiment of the
present invention, and
Fig. 2 is a block diagram of a signal-processing module according to an exemplary
embodiment of the present invention.
[0008] Please refer to Fig. 1, which is a diagram of an antenna module 100 according to
an exemplary embodiment of the present invention. In this embodiment, the antenna
module 100 comprises at least a first antenna 110, at least a second antenna 130,
and a shielding portion 120. The first antenna 110 is utilized to transmit or receive
signals corresponding to a first wireless communication standard, such as WiMAX signals.
The second antenna 130 is utilized to transmit or receive signals corresponding to
a second wireless communication standard, such as WiFi signals. The shielding portion
120 is located between the first antenna 110 and the second antenna 130 for isolating
the first antenna 110 and the second antenna 130 in order to reduce or eliminate interference
between them. As shown in Fig. 1, the shielding portion 120 is a flat board having
two sides, wherein the first antenna 110 is disposed on a first side and the second
antenna 130 is disposed on a second side. In order to reduce the signal interference
between the first antenna 110 and the second antenna 130, at least part of the shielding
portion 120 is made of metal, electromagnetic wave reflection material, electromagnetic
wave absorption material, or materials able to achieve the shielding result. The shape
of the shielding portion 120 is not necessarily limited to the flat board or the round
shape shown in Fig. 1. The shielding portion 120 can have other shapes such as a square,
a rectangular or a polygonal form. Please note that the number and the shape of the
first antenna 110, the second antenna 130 and the shielding portion 120 in Fig. 1
are only an embodiment of the present invention, that is, the number of first antennas
110 and second antennas 130, and the connection and disposition between the shielding
portion 120, the first antenna 110 and the second antenna 130 are not limited to that
shown in Fig. 1. Therefore, other designs obeying the aforementioned spirit all fall
within the scope of the present invention. For example, the first antenna 110 could
comprise a plurality of first antennas etc.
[0009] Moreover, in order to further reduce the signal interference between the first antenna
110 and the second antenna 130, the field directivity of the first antenna 110 and
the second antenna 130 can be designed to become different by performing antenna polarization.
For example, referring to the directions of the arrowheads in Fig. 1, the field of
the first antenna 110 distributes in the first side of the shielding portion 120 and
points upward (assuming that the first side of the shielding portion 120 faces upward),
and the field of the second antenna 130 distributes in the second side and points
horizontally (assuming that the second antenna 130 is disposed vertically) in this
embodiment. Furthermore, if there are a plurality of second antennas 130 in the antenna
module 100, the plurality of second antennas 130 can be equally disposed on the second
side of the shielding portion 120. Each second antenna 130 can be designed to have
a best receiving direction to receive signals from each direction respectively. Therefore,
when one of the second antennas 130 is detected to have the best receiving performance
(for example, the antenna is closest to the base station), the signal of that antenna
can be selected for further processing. Due to the different transmitting/receiving
angles of the first antenna 110 and the second antenna 130 and the shielding effect
of the shielding portion 120, the signal interference situation can be reduced to
almost negligible. Hence, the antenna module 100 is able to transmit or receive signals
of different wireless communication standards.
[0010] Please refer to Fig. 2 in conjunction with Fig. 1. Fig. 2 is a block diagram of a
signal-processing module 200 according to an exemplary embodiment of the present invention.
In this embodiment, the signal-processing module 200 comprises the antenna module
100 shown in Fig. 1, a first processing circuit 202 and a second processing circuit
204. When the antenna module 100 is implemented in the signal-processing module 200
(for example, a laptop or a communication chip), the first processing circuit 202
is coupled to the first antenna 110 to process signals of the first antenna 110 (e.g.
process data to be output or received via the first antenna 110), and the second processing
circuit 204 is coupled to the second antenna 130 to process signals of the second
antenna 130 (e.g. process data to be output or received via the second antenna 130).
Taking the signal-processing module 200 integrating WiMAX and WiFi as an example,
the first antenna 110 can be designed to have an upward transmitting field to transmit
WiFi signals in a small area, and the second antenna 130 can be designed to have a
horizontal field direction to receive WiMAX signals from the WiMAX base station at
a long distance. Since the field of the first antenna 110 distributes in one side
of the shielding portion 120, and the shielding portion 120 provides an effective
isolation between the first and the second antennas, the interference caused by the
WiFi signal to the WiMAX signal at a WiMAX receiving end in the signal-processing
module 200 can be decreased to a minimum, therefore enabling the second processing
circuit 204 to demodulate the received WiMAX signals correctly. After performing some
simulations, it is found that the antenna module 100 can considerably decay WiFi signals
received by the WiMAX receiving end. For example, the intensity of WiFi signals received
by the WiMAX receiving end is at least less than -25dB. Similarly, when the first
antenna 110 receives WiFi signals, the interference caused by the WiMAX signal to
the WiFi signal can be decreased to a minimum as well, enabling the first processing
circuit 202 to demodulate the received WiFi signals correctly. Therefore, the antenna
module 100 provides a considerable shielding effect between the first antenna 110
and the second antenna 130, making the signal-processing module 200 able to process
WiMAX and WiFi signals at the same time while maintaining an excellent communication
quality.
[0011] As can be seen from the above embodiments, the antenna module 100 and the signal-processing
module 200 can successfully solve the interference problem between a short-distance
transmission signal (e.g. WiFi signal) and a long-distance transmission signal (e.g.
WiMAX signal). Hence, as well as processing different kinds of wireless communication
signals simultaneously, the signal-processing module 200 can be applied to integrate
long-distance transmission signals (e.g. WiMAX signals, 3G signals or GSM signals)
with short-distance transmission signals (e.g. WiFi signals or Bluetooth signals).
As the signal-processing module 200 is utilized to transmit/receive a long-distance
transmission signal and a short-distance transmission signal, the receiving end of
the long-distance transmission signal will not be interfered with by the short-distance
transmission signal of stronger intensity, nor will the receiving end of the short-distance
transmission signal be interfered with by the long-distance transmission signal, and
therefore the communication quality can be maintained.
[0012] In addition, the antenna module can be implemented in a laptop, router, wireless
base station, wireless network interface card etc. to provide a communication system
with the ability to process a plurality of wireless communication signals at the same
time while maintaining a good communication quality.
1. An antenna module(100), comprising:
at least a first antenna(110), for transmitting or receiving signals corresponding
to a first wireless communication standard;
at least a second antenna(130), for transmitting or receiving signals corresponding
to a second wireless communication standard; and
characterized by:
a shielding portion(120), disposed between the first antenna(110) and the second antenna(130).
2. The antenna module of claim 1, characterized in that at least part of the shielding portion(120) is made of metal, electromagnetic wave
reflection material or electromagnetic wave absorption material.
3. The antenna module of claim 1, characterized in that field directions of the first antenna(110) and the second antenna(130) are different.
4. The antenna module of claim 1, characterized in that the first antenna(110) is disposed on a first side of the shielding portion(120),
the second antenna(130) is disposed on a second side of the shielding portion(120),
a field of the first antenna(110) distributes in the first side, and a field of the
second antenna(130) distributes in the second side.
5. The antenna module of claim 1, characterized in that one of the first and the second antennas is utilized to transmit or receive a short-distance
transmission signal.
6. The antenna module of claim 5, characterized in that the short-distance transmission signal is a wireless fidelity (WiFi) signal or a
Bluetooth signal.
7. The antenna module of claim 1, characterized in that one of the first and the second antennas is utilized to transmit or receive a long-distance
transmission signal.
8. The antenna module of claim 7, characterized in that the long-distance transmission signal is a Worldwide Interoperability for Microwave
Access (WiMAX) signal, a 3G signal or a Global System for Mobile Communications (GSM)
signal.
9. The antenna module of claim 1, characterized in that one of the first and the second antennas is utilized to transmit or receive a short-distance
transmission signal, and the other of the first and second antennas is utilized to
transmit or receive a long-distance transmission signal.
10. The antenna module of claim 9, characterized in that the short-distance transmission signal is a WiFi signal or a Bluetooth signal, and
the long-distance transmission signal is a WiMAX signal, a 3G signal or a GSM signal.