FIELD OF THE INVENTION

The present invention relates generally to an antenna to produce multiple beams. More particularly, relates to an antenna to produce multiple beams using a single antenna array and a method thereof.

BACKGROUND OF THE INVENTION

WiWi Gen 1.8 Customer Premise Equipment (CPE) includes two wireless technologies which are Worldwide Interoperability for Microwave Access (WiMAX) and WiFi. These technologies employ multiple-input and multiple-output (MIMO) antenna technology. MIMO technology offers significant increases in data throughput and link range without additional bandwidth or transmit power. MIMO technology performance is highly dependent on antenna diversity. Antenna diversity is essential to improve quality and reliability of a wireless link. Antenna diversity can be realized in several ways. Spatial diversity includes multiple antennas, usually with the same characteristics, that are physically separated from one another wherein the physical separation is usually more than half a wavelength. Using spatial diversity scheme, the antennas will be acting independently and they do not have any array gain. Another antenna diversity scheme is polarization diversity wherein pairs of antennas are combined with orthogonal polarizations. This scheme usually requires two antennas wherein the orthogonal polarizations protect a system from polarization mismatches. A single antenna may be used. However this may not be practical and the coverage area is limited by the beamwidth of the antenna.

US 20030095067 discloses a phased antenna array system to generate multiple beams by collecting propagating energy with a number of antenna elements. This system requires a beam forming combiner creating a combined signal from signals received from the antenna elements and also a beam forming computer configured to generate control signals to drive the phase and gain control devices to create multiple beams. The system is a very complex system. US 20100007573 discloses a multibeam antenna wherein the multibeam antenna creates diversity. The system requires multiple antenna arrays to produce multiple beams. A large amount of hardware is required to materialize this.

There is a need for an apparatus to produce multiple beams using a single antenna array without requiring a complex system.

SUMMARY OF THE INVENTION

It is disclosed herein an antenna to produce multiple beams, wherein the antenna includes:

a) a first input port;

b) a second input port; and

c) plurality of antenna elements;

wherein the plurality of antenna elements are included in a single antenna array;

wherein a wireless signal is inputted through the first and the second input ports simultaneously and the wireless signal is then divided and fed to the plurality of antenna elements from a predetermined location along the peripheral of the plurality of antenna elements.

It is also disclosed herein, a method of producing multiple beams using an antenna, the method includes the steps of:

a) inputting a wireless signal simultaneously through a first input port and a second input port of the antenna; b) dividing the wireless signal simultaneously;

c) feeding the wireless signal to the plurality of antenna elements simultaneously from a predetermined location along the peripheral of the plurality of antenna elements;

wherein the wireless signal inputted through the first input port which has been divided is fed to the plurality of antenna elements at parallel locations along the peripheral of the plurality of antenna elements; wherein the wireless signal inputted through the second input port which has been divided is fed to at least one antenna element at parallel location along the peripheral of the at least one first antenna element and fed to at least one second antenna element at location opposing to the location of wireless signal fed to the at least one first antenna element; and

d) adding the wireless signal simultaneously. BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 illustrates an antenna according to a preferred embodiment of the invention.

Figure 2 illustrates a method of producing multiple beams according to a preferred embodiment of the invention.

Figure 3 illustrates an antenna according to another preferred embodiment of the invention.

Figure 4 illustrates an antenna according to yet another preferred embodiment of the invention. Figure 5 illustrates radiation pattern according to a preferred embodiment of the invention.

Figure 6 illustrates another radiation pattern according to a preferred embodiment of the invention.

Figure 7 illustrates a measurement graph of radiation patterns. DETAILED DESCRIPTION OF THE INVENTION

The invention and its various embodiments are better understood by reading the description along with the accompanying drawings which appear herein for purpose of illustration only and do not limit the invention in any way.

Figure 1 illustrates configuration of an apparatus according to a preferred embodiment of the invention. The apparatus is a dual beam printed antenna (102) including a dielectric substrate having a first and a second surface. The first surface includes plurality of antenna elements (108, 1 10, 1 12, 1 14) whereas the second surface includes a ground plane. The plurality of antenna elements (108, 1 10, 1 12, 1 14) are preferably arranged in a MxN configuration wherein M > 1 and N≥ 2. M represents number of column arranging plurality of antenna elements (108, 1 10, 1 12, 1 14) whereas N represents number of rows arranging the plurality of antenna elements (108, 1 10, 1 12, 1 14). The plurality of antenna elements (108, 1 10, 1 12, 1 14) are separated by a predetermined distance wherein the distance is at least half the wavelength of operating wireless signal frequency. The plurality of antenna elements (108, 1 10, 112, 1 14) are preferably rectangular in shape but may also be circular or of any other shapes.

Figure 2 illustrates a method of producing diverse beams according to a preferred embodiment of the invention. A wireless signal is simultaneously inputted through a first input port (104) and the second input port (106) of the antenna (102) (2.1 ). The wireless signal is divided and simultaneously fed to the plurality of antenna elements (108, 1 10, 1 12, 1 14) from a predetermined location along the peripheral of the plurality of antenna elements (108, 1 10, 1 12, 1 14). The wireless signal inputted through the first input port (104) which has been divided is fed to the plurality of antenna elements (108, 1 10, 1 12, 1 14) simultaneously at parallel locations (120, 122, 124, 126) along the peripheral of the plurality of antenna elements (108, 1 10, 1 12, 1 14) (2.3). The signal is added wherein a single beam (21 1 ) in perpendicular direction is produced (2.4).

The wireless signal inputted through the second input port (106) which has been divided is fed to the plurality of antenna elements (108, 110, 1 12, 1 14) at parallel locations (130, 132) along the peripheral of the plurality of antenna elements (108, 110) and fed to the plurality of antenna elements (1 12, 1 14) at locations (134, 136) opposing to the locations (130, 132) of wireless signal fed to the plurality of antenna elements (108, 1 10) (2.5). The wireless signal is added wherein a dual beam (212) is produced (2.6). The dual beam (212) is produced in the broadside with a null in the perpendicular direction.

Figure 3 illustrates another configuration of plurality of antenna elements (108, 1 12) according to an embodiment of the invention. The wireless signal is simultaneously inputted through the first input port (104) and the second input port (106) of the antenna ( 02) (2.1 ). The wireless signal is divided (2.2) and simultaneously fed to the plurality of antenna elements (108, 1 12) from a predetermined location along the peripheral of the plurality of antenna elements (108, 112). The wireless signal inputted through the first input port (104) which has been divided is fed to the plurality of antenna elements (108, 1 12) simultaneously at parallel locations (120, 122) along the peripheral of the plurality of antenna elements (108, 1 12) (2.3). The signal is added wherein a single beam (21 1 ) in perpendicular direction is produced (2.4).

The wireless signal inputted through the second input port (106) is fed to the antenna element (108) at parallel location (130) along the peripheral of the antenna element (108) and fed to antenna element (1 12) at location (134) opposing to the location (130) of wireless signal fed to the antenna element (108) (2.5). The wireless signal is added wherein a dual beam (212) is produced (2.6). The dual beam (212) is produced in the broadside with a null in the perpendicular direction. Figure 4 illustrates another of plurality of antenna elements (108, 1 10, 1 12, 1 14, 140, 142) according to another embodiment- of the invention. The wireless signal inputted through the first input port (104) which has been divided is fed to the plurality of antenna elements (108, 1 10, 1 12, 1 14, 140, 142) simultaneously at parallel locations along the peripheral of the plurality of antenna elements (108, 110, 1 12, 1 14, 140, 142) (2.3). The signal is added wherein a single beam (21 1) in perpendicular direction is produced (2.4).

The wireless signal inputted through the second input port (106) is fed to the antenna elements (1 12, 1 14, 140, 142) at parallel location along the peripheral of the plurality of antenna elements (1 12, 1 14, 140, 142) and fed to the plurality of antenna elements (108, 1 10) at locations opposing to the location of wireless signal fed to the plurality of antenna elements (1 12, 1 14, 140, 142) (2.5). The wireless signal is added wherein a dual beam (212) is produced (2.6). The dual beam (212) is produced in the broadside with a null in the perpendicular direction.

Figure 5 illustrates radiation pattern produced by inputting the wireless signal through the first input port (104) wherein a single beam (21 1) in perpendicular direction is produced.

Figure 6 illustrates radiation pattern produced by inputting wireless signal through the second input port (106) a dual beam (2 2) is produced in the broadside with a null in the perpendicular direction.

Figure 7 illustrates a measurement graph of the radiation patterns produced by a preferred embodiment of the invention. The main beam is illustrated as (501 ) whereas the split beam is illustrated as (502).