Patent Publication Number: US-2022231410-A1

Title: Anti-Interference Microwave Antenna

Description:
CROSS REFERENCE OF RELATED APPLICATION 
     This is a Continuation-In-Part application that claims the benefit of priority under 35 U.S.C.§ 120 to a non-provisional application, application Ser. No. 16/862,592, filed Apr. 30, 2020, which is a Continuation application that claims the benefit of priority under 35 U.S.C.§ 120 to a non-provisional application, application Ser. No. 16/244,116, filed Jan. 10, 2019, which is a Continuation application that claims the benefit of priority under 35 U.S.C.§ 120 to a non-provisional application, patent Ser. No. 10,263,327, issued Apr. 16, 2019, which is Continuation application that claims the benefit of priority under 35 U.S.C.§ 120 to a non-provisional application, application Ser. No. 16/035,689, filed Jul. 15, 2018, which is a non-provisional that claims which claims priority under 35 U.S.C. 119(a-d) to Chinese application number 201810595979.X, filed Jun. 11, 2018. The afore-mentioned patent applications are hereby incorporated by reference in their entireties. 
    
    
     BACKGROUND OF THE PRESENT INVENTION 
     Field of Invention 
     The present invention relates to an antenna, and more particularly to an antenna with an anti-interference arrangement, wherein the anti-interference arrangement prevents electromagnetic wave signals received or generated by the antenna from being interfered by the nearby electromagnetic radiation frequency or the stray radiation frequency, so as to enhance the anti-interference ability of the antenna. 
     Description of Related Arts 
     Industrial Scientific and Medical (ISM) Bands are designated by ITU-R (ITU Radio-communication Sector) and are unlicensed radio bands reserved internationally for the use of radio frequency (RF) telecommunications by institutions such as industry, science, and medicine institutions. During the use of these bands, the transmission power thereof must be restricted (usually lower than 1W) and must not be interfere with other frequency bands. Nowadays, these ITU-R opened frequency bands being used for microwave detection are mainly set at 2.4 GHz, 5.8 GHz, 10.52 GHz, and 24.125 GHz. In recent years, new frequency bands are frequently utilized for the application of microwave detection. For example, the application of 5G technology will cause a new frequency band being used for microwave detection in addition to the existing frequency bands being already used for microwave detection. It is known that there will be a mutual interference when two or more frequency bands are used closely. For the microwave detection as an example, when the 5.8 GHz of frequency band is used for human or object motion detection, such 5.8 GHz of frequency band will be inevitably interfered by the application of 5 G technology. As a result, the interference of the application of 5 G technology will cause the inaccuracy of the detection result from the 5.8 GHz of frequency band. As the 5 G technology is rapidly well-developed recently, the 5 G system will be more open and the application thereof will be widely used. It can be foreseen that the large-scale application of 5 G technology will inevitably form a high speed based on 5 G data network and will continuously expand more frequency bands in the future. In other words, the possibility of interference of the frequency bands for the microwave detection will be highly increased by the application of 5 G technology. Therefore, it is urgent to improve the antennas with anti-interfering ability for the microwave detection. Accordingly, a conventional method for enhancing the anti-interfering ability for the microwave detection antenna is the suppression method by shielding external wireless signals, signal filtering, and software algorithm processing to suppress the interference. However, such conventional method can only provide limited anti-interfering ability for limited frequency bands. Therefore, a need exists for an antenna that enhances the anti-interfering ability to different frequency bands. It is to the provision of such an antenna that the present disclosure is primarily directed. 
     SUMMARY OF THE PRESENT INVENTION 
     The invention is advantageous in that it provides an antenna with an anti-interference arrangement and method, wherein the anti-interference arrangement enhances the anti -interference ability of the antenna. 
     Another advantage of the invention is to an antenna with an anti-interference arrangement and method, wherein the anti-interference arrangement prevents electromagnetic wave signals received or generated by the antenna from being interfered by the nearby electromagnetic radiation frequency or the stray radiation frequency. 
     Another advantage of the invention is to an antenna with an anti-interference arrangement and method, wherein the impedance of the antenna is lowered to narrow the bandwidth thereof so as to prevent electromagnetic wave signals received or generated by the antenna from being interfered by the nearby electromagnetic radiation frequency or the stray radiation frequency. 
     Another advantage of the invention is to an antenna with an anti-interference arrangement and method, wherein the impedance of the antenna is lowered to enhance the radiating energy of the primary radiating wave within its radiating wave band, so as to reduce the harmonic radiation of the antenna. 
     Another advantage of the invention is to an antenna with an anti-interference arrangement and method, wherein the anti-interference circuit has a low impedance to match with the low impedance of the antenna in order to narrow the bandwidth of the antenna so as to prevent any interference of electromagnetic wave signals received or generated by the antenna of the present invention in response to the nearby electromagnetic radiation frequency. 
     Another advantage of the invention is to an antenna with an anti-interference arrangement and method, wherein the radiating source is grounded to reduce the impedance of the antenna. 
     Another advantage of the invention is to an antenna with an anti-interference arrangement and method, wherein the radiating source is electrically connected to the reference ground to ground the radiating source. 
     Another advantage of the invention is to an antenna with an anti-interference arrangement and method, wherein the anti-interference circuit provides a relatively large excitation current to the radiating source to ensure the stable operation of the antenna. 
     Another advantage of the invention is to an antenna with an anti-interference arrangement and method, wherein the radiating source has at least a radiating connection point electrically connected to the reference ground. A distance between the periphery of radiating source and the radiating connection point thereof is preset to generate an inductance therebetween under the excitation of the microwave excitation electrical signal. 
     Another advantage of the invention is to an antenna with an anti-interference arrangement and method, wherein a distance between at least one feed point and at least one radiating connection point is greater than or equal to 1/64λ to generate an inductance therebetween under the excitation of the micro wave excitation electrical signal. 
     Another advantage of the invention is to an antenna with an anti-interference arrangement and method, wherein by forming the radiating connection point of the radiating source at the physical center point thereof, the impedance of the antenna will be lowered under resonance state to enhance the anti-interference ability of the antenna. 
     Another advantage of the invention is to an antenna with an anti-interference arrangement and method, wherein the electrical connection element has two terminal ends electrically connecting with the radiating source and the reference ground respectively to reduce the internal impedance of the antenna under resonance state so as to enhance the anti-interference ability of the antenna. 
     Another advantage of the invention is to an antenna with an anti-interference arrangement and method, wherein the radiating connection point is overlapped with the feed point to electrically connect the feed point with the reference ground for reducing the internal impedance of the antenna under resonance state so as to enhance the anti-interference ability of the antenna. 
     Additional advantages and features of the invention will become apparent from the description as follows and may be realized by means of the instrumentalities and combinations particular point out in the appended claims. 
     According to the present invention, the foregoing and other objects and advantages are attained by an antenna, comprising: 
     a reference ground; and 
     at least one radiating source spacedly disposed at the reference ground to define a radiating clearance between the radiating source and the reference ground, wherein the radiating source is electrically connected to the reference ground to ground the radiating source so as to narrow a bandwidth of the antenna. 
     In one embodiment, the at least one radiating source has at least one feed point and at least one radiating connection point, wherein the at least one feed point deviates from a physical center point of the at least one radiation source. 
     In one embodiment, a same set of radiating connection points are respectively positioned at vertices of a regular polygon having a center point which is the physical center point of the at least one radiating source, wherein the radiating connection points of the same set of radiating connection points are arranged to each having an equal distance with respect to the physical center point of the corresponding radiating source and distributed around the physical center point of the corresponding radiating source with equal angle therebetween. 
     In one embodiment, the at least one radiating source is electrically connected to the reference ground at the radiating connection points of the at least one radiating source so as to feed in excitation signals at the at least one feed point of the at least one radiating source, wherein since the at least one radiating source is electrically connected with the reference ground at the radiating connection points, a zero potential point is formed at the physical center point of the at least one radiating source and an equivalent connection with the reference ground so as to narrowing a bandwidth of the antenna. 
     In one embodiment, a same pair of radiating connection points are symmetrically distributed at the at least one radiating source with respect to the physical center point of the at least one radiating source, wherein in correspondence to connection lines between the same pair of the radiating connection points and a center point which is the physical center point of the at least one radiating source, wherein the at least one radiating source is electrically connected with the reference ground at the radiating connection points, so as to receive excitation signals at the at least one feed point of the at least one radiating source, wherein since the at least one radiating source is electrically connected with the reference ground at the radiating connection points, a zero potential point is formed at the physical center point of the at least one radiating source and an equivalent connection with the reference ground so as to narrowing a bandwidth of the antenna. 
     In one embodiment, the antenna provides at least two feed points distributed at the at least one radiating source around the physical center point thereof evenly and symmetrically, wherein the radiating source is arranged in such a manner that the at least two feed points are connected for at least two excitation signals with opposite phases so as to enable the at least two feed points to be distributed in symmetrical form with respect to the physical center point to strengthen the zero potential characteristic of the physical center point of the at least one radiating source. 
     In one embodiment, the antenna provides at least two feed points distributed at the at least one radiating source, wherein each of the feed points can be fed with excitation signals and emit electromagnetic waves, or receive electromagnetic waves, including the reflecting waves generated and reflected from the object that the emitted electromagnetic waves encountered. 
     In one embodiment, the antenna provides at least two feed points distributed at the at least one radiating source, wherein a first feed point of the at least two feed points is configured to emit electromagnetic waves and a second feed point of the at least two feed points is configured to receive electromagnetic waves while the first and second feed points have a predetermined distance therebetween and are preferably arranged perpendicularly. 
     In one embodiment, the antenna provides at least two feed points distributed at the at least one radiating source, wherein each of the at least two feed points has a polarization direction (i.e. the direction from the feed point to the physical center point of the radiating source) arranged in perpendicular manner with respect to the physical center point of the radiating source, so as to respectively receive at least two excitation signals with a phase difference of 90 degrees to form an antenna with circular polarization, or alternatively, one of the at least two feed points is configured for receiving excitation signals and another one of the at least two feed points is configured for receiving the corresponding feedback signals so as to enable the antenna achieving a certain degree of isolation of transceiver separation. 
     In one embodiment, the antenna provides two feed points in a such a manner that connection lines between the two feed points to the physical center point of the at least one radiating source are perpendicular with each other. 
     In one embodiment, the antenna provides three feed points, wherein a first feed point and a second feed point of the three feed points are symmetrically distributed at the at least one radiating source with respect to the physical center point of the at least one radiating source, while a third feed point of the three feed points is arranged in such a manner that a connecting line between the third feed point and the physical center point of the radiating source is perpendicular to a connecting line between the first and the second feed points of the three feed points. 
     In one embodiment, the antenna provides four feed points, wherein each of the four feed points is distributed at an equal angle around the physical center point of the at least one radiating source while an equal distance is arranged between each of the four feed points with the physical center point of the at least one radiating source which is electrically connected to the reference ground. 
     In one embodiment, the radiating source is in the form of a metal patch spacedly and intervally arranged on one side of the reference ground. 
     In accordance with another aspect of the invention, the present invention comprises a method of manufacturing an antenna which comprises at least a radiating source and a reference ground, comprising the following steps. 
     (A) Spacedly dispose the radiating source at the reference ground to define a radiation clearance between the radiating source and the reference ground. 
     (B) Electrically connect the radiating source to the reference ground to ground the radiating source so as to narrow a bandwidth of the antenna. 
     In accordance with another aspect of the invention, the present invention comprises a method of enhancing an anti-interference ability of an antenna which comprises at least a radiating source and a reference ground, comprising the following steps. 
     (1) Form a radiating clearance between the radiating source and the reference ground. 
     (2) Ground the radiating source by electrically connecting the radiating source to the reference ground to reduce an internal impedance of the antenna, such that when an electromagnetic excitation signal is received at a feed point of the radiating source, a bandwidth of the antenna is narrowed down to prevent any interference of the electromagnetic wave signal received or generated by the antenna in response to nearby electromagnetic radiation frequency or stray radiation frequency of the adjacent frequency bands. 
     Still further objects and advantages will become apparent from a consideration of the ensuing description and drawings. 
     These and other objectives, features, and advantages of the present invention will become apparent from the following detailed description, the accompanying drawings, and the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an antenna with an anti-interference arrangement according to a first preferred embodiment of the present invention. 
         FIG. 2  is a sectional view of the antenna according to the above first preferred embodiment of the present invention. 
         FIG. 3  illustrates a first alternative mode of the antenna according to the above first preferred embodiment of the present invention. 
         FIG. 4  illustrates a second alternative mode of the antenna according to the above first preferred embodiment of the present invention. 
         FIG. 5  is a sectional view of the second alternative mode of the antenna according to the above first preferred embodiment of the present invention. 
         FIG. 6  illustrates a third alternative mode of the antenna according to the above first preferred embodiment of the present invention. 
         FIG. 7A  illustrates a fourth alternative mode of the antenna according to the above first preferred embodiment of the present invention. 
         FIG. 7B  is a sectional view of the fourth alternative mode of the antenna according to the above first preferred embodiment of the present invention. 
         FIG. 8  is an anti-interference circuit diagram of the antenna according to the above first preferred embodiment of the present invention. 
         FIG. 9  is a perspective view of an antenna with an anti-interference arrangement according to a second preferred embodiment of the present invention. 
         FIG. 10  is a sectional view of the antenna according to the above second preferred embodiment of the present invention. 
         FIG. 11  is a perspective view of an antenna with an anti-interference arrangement according to a third preferred embodiment of the present invention. 
         FIG. 12  is a sectional view of the antenna according to the above third preferred embodiment of the present invention. 
         FIG. 13  is a perspective view of an antenna with an anti-interference arrangement according to a fourth preferred embodiment of the present invention. 
         FIG. 14  is a sectional view of the antenna according to the above fourth preferred embodiment of the present invention. 
         FIG. 15  illustrates an alternative mode of the antenna according to the above fourth preferred embodiment of the present invention. 
         FIGS. 16A to 16E  are schematic views illustrating distributions of one or more feed points with respect to a physical center point of a radiating source of the antenna with anti-interference arrangement according to the above preferred embodiments of the present invention. 
         FIGS. 17A to 17H  are schematic views illustrating distribution of the radiating connection points with respect to the physical center point of the radiating source of the antenna with anti-interference arrangement according to the above preferred embodiments of the present invention. 
         FIG. 18  is a schematic view illustrating an example of distribution of the feed points and the radiating connection points with respect to the physical center point of the radiating source of the antenna with anti-interference arrangement according to the above preferred embodiments of the present invention. 
     
    
    
     The drawings, described above, are provided for purposes of illustration, and not of limitation, of the aspects and features of various examples of embodiments of the invention described herein. The drawings are not intended to limit the scope of the claimed invention in any aspect. For simplicity and clarity of illustration, elements shown in the drawings have not necessarily been drawn to scale and the dimensions of some of the elements may be exaggerated relative to other elements for clarity. 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The following description is disclosed to enable any person skilled in the art to make and use the present invention. Preferred embodiments are provided in the following description only as examples and modifications will be apparent to those skilled in the art. The general principles defined in the following description would be applied to other embodiments, alternatives, modifications, equivalents, and applications without departing from the spirit and scope of the present invention. 
     It is appreciated that the terms “longitudinal”, “transverse” , “upper”, “lower”, “front”, “rear” “left”, “right”, “vertical” , “horizontal” , “top”, “bottom”, “exterior”, and “interior” in the following description refer to the orientation or positioning relationship in the accompanying drawings for easy understanding of the present invention without limiting the actual location or orientation of the present invention. Therefore, the above terms should not be an actual location limitation of the elements of the present invention. 
     It is appreciated that the terms “one”, “a”, and “an” in the following description refer to “at least one” or “one or more” in the embodiment. In particular, the term “a” in one embodiment may refer to “one” while in another embodiment may refer to “more than one”. Therefore, the above terms should not be an actual numerical limitation of the elements of the present invention. 
     Referring to  FIGS. 1 and 2  of the drawings, an antenna according to a preferred embodiment of the present invention is illustrated, wherein the antenna comprises a reference ground  10  and at least a radiating source  20  spacedly disposed at the reference ground  10  on a first side  101  thereof to form an antenna body. Accordingly, the antenna further comprises an oscillating circuit electrically coupled to the antenna body. 
     It is worth mentioning that the radiating source  20  of the present invention is spaced apart from the reference ground  10  that there is not direct contact between the reference ground  10  and the radiating source  20 . In particular, a space is formed between the reference ground  10  and the radiating source  20  as a radiating clearance  30  therebetween. 
     Furthermore, the radiating clearance  30  defined between the reference ground  10  and the radiating source  20  refers a surface difference between a surface of the reference ground  10  and a surface of the radiating source  20 . In one embodiment, the radiating clearance  30  defined between the reference ground  10  and the radiating source  20  is a height difference between the first side  101  of the reference ground  10  and an outer surface of the radiating source  20 , as shown in  FIGS. 1 and 2 . In another embodiment, the radiating clearance  30  defined between the reference ground  10  and the radiating source  20  is a gap between the first side  101  of the reference ground  10  and a circumferential surface of the radiating source  20 , as shown in  FIGS. 7A and 7B . Therefore, the formation of the radiating clearance  30  between the reference ground  10  and the radiating source  20  should not be limited by only two designated surfaces thereof. 
     As shown in  FIGS. 1 and 2 , the radiating source  20  is electrically connected to the reference ground  10 , wherein the radiating source  20  is grounded. It is worth mentioning that the configuration of the conventional antenna is that the radiating source is not grounded and is not electrically connected to the reference ground. By grounding the radiating source  20 , an impedance of the antenna of the present invention can be substantially reduced to narrow down a bandwidth of the antenna, so as to avoid any interference of electromagnetic wave signals received or generated by the antenna of the present invention by electromagnetic radiation frequency or stray radiation frequency of the adjacent frequency bands. 
     As shown in  FIGS. 1 and 2 , the radiating source  20  has at least a radiating connection point  21  and a feed point  22 . The reference ground  10  further has at least a reference ground connection point  11 . The radiating connection point  21  of the radiating source  20  is electrically connected to the reference ground connection point  11  of the reference ground  10 , such that the radiating source  20  is grounded. In addition, the feed point  22  of the radiating source  20  is arranged to be connected to an excitation current. 
     Accordingly, the oscillating circuit is connected to the feed point  22  of the antenna body to generate the electromagnetic wave signal (microwave excitation electrical signal). Once the excitation current is received by the feed point  22  of the radiating source  20 , the antenna will initialize at a polarization direction that the radiating source  20  will generate radiate energy at a radial and outward direction. As it is mentioned, the radiating source  20  is electrically connected to the reference ground  10  to ground the radiating source  20 . Once the excitation current is received by the feed point  22  of the radiating source  20 , a predetermined impedance is generated between the radiating connection point  21  and the feed point  22  of the radiating source due to the inductance characteristics therebetween. As a result, the antenna will be excited and initialized at a polarization direction to generate radiate energy at the radiating source  20  at a radial and outward direction. At the same time, the impedance will be lowered between the radiating connection point  21  and the feed point  22  of the radiating source due to the inductance characteristics therebetween, so as to narrow down the bandwidth of the antenna. By narrowing the bandwidth of the antenna, any interference of electromagnetic wave signals received or generated by the antenna of the present invention will be substantially reduce in response to the electromagnetic radiation frequency or stray radiation frequency of the adjacent frequency bands. It is worth mentioning that the feed point  22  of the radiating source  20  must be deviated from a physical center point thereof, so that it is easily excited by the excitation current. In addition, there must be an impedance between the radiating source  20  and the reference ground  10  in order to excite the radiating source  20 . Even though the radiating connection point  21  of the radiating source  20  is grounded, the impedance will be generated between the radiating connection point  21  and the feed point  22  in response to the inductance characteristics therebetween under the high frequency excitation signal. It is worth mentioning that even the impedance is generated, such impedance is relatively low. 
     It is worth mentioning that the impedance of the antenna is lowered to enhance the radiating energy of the primary radiating wave within its radiating wave band, so as to reduce the harmonic radiation of the antenna. Accordingly, the antenna not only generates the electromagnetic waves in its radiation frequency band but also generates harmonic wave at frequency multiplication of its radiation frequency band, which is stray radiation. 
     Preferably, a distance between the radiating connection point  21  and the feed point  22  of the radiating source  20  is greater than or equal to 1/64λ, where λ, is the wavelength of the electromagnetic wave signal received or generated by the antenna. 
     Under the excitation of the excitation electrical signal, the electromagnetic wave signal will generate the inductance characteristics between the radiating connection point  21  and the feed point  22  of the radiating source  20 . Since the feed point  22  of the radiating source  20  is deviated from the physical center point thereof, the intensity required for the excitation current of the antenna to the electromagnetic wave signal will be substantially reduced. As a result, once the excitation current is received by the feed point  22  of the radiating source  20 , the antenna is easily initialized at a polarization direction. 
     As shown in  FIGS. 1 and 2 , the radiating connection point  21  of the radiating source  20  is preferably defined as the physical center point thereof. In other words, the physical center point of the radiating source  20  is electrically connected to the reference ground  10  to ground the radiating source  20 . Therefore, by forming the radiating connection point  21  of the radiating source  20  at the physical center point thereof, the antenna can evenly and stably generate the radiate energy via the radiating source  20  in a radial and outward direction after the initial polarization direction is generated. It should be understood by a person who skilled in the art that the inductance is generated between the periphery of the radiating source  20  and the feed point  22  thereof under the excitation of the excitation current, and the resonant circuit of the antenna with a distributed capacitance is generated between the radiating source  20  and the reference ground  10  for receiving or generating the electromagnetic wave signal. 
     As shown in  FIGS. 1 and 2 , there is one radiating connection point  21  of the radiating source  20 . In another embodiment as shown in  FIG. 3 , there are two or more radiating connection points  21  of the radiating source  20 , wherein the physical center point of the radiating source  20  is surrounded by the radiating connection points  21  of the radiating source  20 . In addition, a distance between the periphery of radiating source  20  and the radiating connection points  21  thereof is preset. Under the excitation of the electromagnetic wave signal, the inductance characteristics will be generated between the radiating connection point  21  and the feed point  22  of the radiating source  20 . Then, when the excitation current is received by the feed point  22  of the radiating source  20 , the impedance of the antenna is lowered to narrow down the bandwidth thereof. In addition, a distance between the feed point  22  and any one of the radiating connection points  21  is greater than or equal to 1/64λ, as shown in  FIG. 3 . 
     As shown in  FIGS. 1 and 2 , the antenna further comprises an electrical connection element  40  having two terminal ends electrically connecting with the radiating connection point  21  of the radiating source  20  and the reference ground connection point  11  of the reference ground  10  respectively. Therefore, the electrical connection element  40  forms an electrical connection media to electrically connect the radiating source  20  and the reference ground  10  with each other so as to ground the radiating source  20 . 
     As shown in  FIGS. 1 and 2 , the radiating connection point  21  of the radiating source  20  is preferably aligned with the reference ground connection point  11  of the reference ground  10 . In other words, the extension direction between the radiating connection point  21  of the radiating source  20  and the reference ground connection point  11  of the reference ground  10  is perpendicular to the first side of reference ground  10 . 
     It is worth mentioning that the electrical connection element  40  is preferably coupled between the radiating source  20  and the reference ground  10 , such that the terminal ends of the electrical connection element  40  can be electrically connected to the radiating connection point  21  of the radiating source  20  and the reference ground connection point  11  of the reference ground  10  respectively, so as to electrically connect the radiating source  20  with the reference ground  10 . According to the preferred embodiment as one of the examples, the radiating source  20  is initially retained adjacent to the first side  101  of the reference ground  10  to form the radiating clearance  30  between the reference ground  10  and the radiating source  20 . Then, a reference ground slot  12  is formed at an opposed second side  102  of the reference ground  10 , wherein the reference ground slot  12  is extended corresponding to the radiating source  20 . It should be understood that the radiating clearance  30  between the radiating source  20  and the reference ground  10  is a solid media, as shown in  FIGS. 1 and 2 . In other words, at the same time when the reference ground slot  12  is formed, a clearance slit  31  is also formed within the radiating clearance  30 , wherein the reference ground slot  12  of the reference ground  10  is communicated with and extended through the clearance slit  31  of the radiating clearance  30 . The radiating connection point  21  of the radiating source  20  is set corresponding to the reference ground slot  12  of the reference ground  10  and the clearance slit  31  of the radiating clearance  30 . Next, a molding element is sequentially extended to the reference ground slot  12  of the reference ground  10  and the clearance slit  31  of the radiating clearance  30  in order to connect the molding element to the radiating connection point  21  of the radiating source  20  and to connect the molding element to the reference ground  10 . Therefore, the molding element is configured as the electrical connection element  40  to electrically connect the radiating source  20  and the reference ground  10  with each other. In addition, the connection point between the molding element and the reference ground  10  becomes the reference ground connection point  11  thereof. 
     It is worth mentioning that the molding element can be, but not limited to, a gold wire, silver wire or other conducive wires according to the preferred embodiment. When the molding element is used as the connection wire, the connection wire is extended from the reference ground slot  12  of the reference ground  10  and the clearance slit  31  of the radiating clearance  30  to the radiating connection point  21  of the radiating source  20  and to connect to the reference ground  10 , so as to form the electrical connection element  40  to electrically connect the radiating source  20  and the reference ground  10  with each other. Alternatively, one end of the connection wire is initially connected to the radiating connection point  21  of the radiating source  20 . Then, the radiating source  20  is retained close to the first side  101  of the reference ground  10 , wherein the connection wire is extended through the reference ground slot  12  of the reference ground  10  to connect with the reference ground  10 , so as to form the electrical connection element  40  to electrically connect the radiating source  20  and the reference ground  10  with each other. In one embodiment, the molding element can be, but not limit to, fluid material, wherein the molding element is filled into the reference ground slot  12  of the reference ground  10  and the clearance slit  31  of the radiating clearance  30 . Once the molding element is solidified, the molding element forms the electrical connection element  40  to electrically connect the radiating source  20  and the reference ground  10  with each other. 
     As shown in  FIGS. 1 and 2 , the antenna further comprises a shield member  50  coupled at the reference ground  10  at the second side  102  thereof. 
     Accordingly, the shape of the radiating source  20  of the antenna should not be limited. For example, the radiating source  20  can be configured to have a rectangular shape as shown in  FIGS. 1 to 3 . It could be configured to have a square shape as well. Likewise, the radiating source  20  can be configured to have a circular shape or oval shape as shown in  FIGS. 4 and 5 . In other word, the extension direction of the radiating source  20  is the same as that of the reference ground  10 , i.e. the radiating source  20  is parallel to the reference ground  10 , to form a flat panel antenna. In other embodiment as shown in  FIGS. 7A and 7B , the extension direction of the radiating source  20  is the perpendicular to that of the reference ground  10 , i.e. the radiating source  20  is perpendicular to the reference ground  10 , to form a column type antenna. As shown in  FIGS. 7A and 7B , the antenna further comprises at least a supplement inductor  100 , wherein one end of the supplement inductor  100  is electrically connected to the radiating connection point  21  of the radiating source  20  while another end of the supplement inductor  100  is grounded. As shown in  FIG. 6 , the radiating source  20  is formed as part of the flat panel antenna with the supplement inductor  100 , wherein one end of the supplement inductor  100  is electrically connected to the radiating connection point  21  of the radiating source  20  while another end of the supplement inductor  100  is grounded. 
     As shown in  FIG. 8 , the antenna further comprises an anti-interference circuit  60  electrically connected to the feed point  22  of the radiating source  20  to enable the excitation current passing through the anti-interference circuit  60  to the feed point  22  of the radiating source  20 . The anti-interference circuit  60  has a low impedance to provide the excitation current to match with the low impedance of the antenna so as to enable the antenna generating the initial polarization direction. As a result, the impedance of the antenna will be reduced and the bandwidth of the antenna will be narrowed down such that any interference of electromagnetic wave signals received or generated by the antenna of the present invention will be substantially reduced in response to the nearby electromagnetic radiation frequency or stray radiation frequency of the adjacent frequency bands. 
     As shown in  FIG. 8 , the antenna further comprises an analog circuit  70  electrically connected with the radiating source  20  and the reference ground  10  for being excited by the excitation current. As shown in  FIG. 8 , the analog circuit  70  comprises a first analog point  71  analogously representing to the radiating connection point  21  of the radiating source  20  and a second analog point  72  analogously representing to the feed point  22  of the radiating source  20 . It is worth mentioning that the antenna body is excited by the excitation current from the oscillating circuit, it performs as the analog circuit  70  to be excited. 
     In particular, the anti-interference circuit  60  comprises an oscillation circuit module  61  (i.e. the oscillating circuit) and a mixing detection circuit module  62  electrically connected to the oscillation circuit module  61 . Accordingly, the second analog point  72  of the analog circuit  70  is electrically connected to the oscillation circuit module  61  of the anti-interference circuit  60 . The mixing detection circuit module  62  is located and retained between the oscillation circuit module  61  and the radiating source  20 . The mixing detection circuit module  62  adapts the low-impedance output of the oscillation circuit module  61  and the low impedance of the antenna to be grounded, so as to ensure the stability and reliability of the operation of the antenna. In other words, the feed point  22  f the radiating source  20  is electrically connected to the oscillation circuit module  61  of the anti-interference circuit  60 . 
     Accordingly, once the impedance of the antenna is lowered, its bandwidth will be narrowed to enhance the anti-interference ability. The impedance of the existing antenna can be configured as low as  50  ohms. However, the impedance of the existing antenna cannot be further lowered below  50  ohms because of the conventional oscillating circuit. On the other hand, the oscillation circuit module  61  of the present invention is configured to match with the low impedance antenna in order to further reduce the impedance of the antenna. In other words, the strength of the excitation current for the low impedance antenna will be greater. However, under the emission power regulation of the antenna, the conventional oscillating circuit cannot provide such great excitation current. Therefore, the oscillation circuit module  61  of the present invention must have a low impedance to match with the low impedance antenna. 
     Accordingly, the anti-interference circuit  60  can be set in the reference ground  10 . For example, the anti-interference circuit  60  can be printed or coated on the reference ground  10  or can be etched on the reference ground  10 . In other words, the method of forming the anti-interference circuit  60  on the reference ground  10  should not be limited in the present invention. 
     Preferably, the connection between the oscillation circuit module  61  and the mixing detection circuit module  62  of the anti-interference circuit  60 , and the connection between the mixing detection circuit module  62  and the feed point  22  of the radiating source  20  can be the capacitive coupling connections. So, the mixing detection circuit module  62  adapts the low-impedance output of the oscillation circuit module  61  and the low impedance of the antenna to be grounded, to effectively suppress the differential interference from coupling and the common interference from the reception of the antenna, so as to enhance the anti-interference ability of the antenna. It is worth mentioning that the antenna is used for human body movement detection. Due to the Doppler effect, there will be a difference in the wavelengths between the received and transmitted electromagnetic waves. Therefore, it is necessary to distinguish the received and transmitted electromagnetic waves by the mixing detection circuit module  62  to obtain a differential value for the calculation of the related movement data. In other words, the mixing detection circuit module  62  can be disabled when the antenna is used for data transmission. 
     As shown in  FIG. 8 , the anti-interference circuit  60  has a low impedance and a relatively large excitation current, that matches with the low impedance of the antenna, to the feed point  22  of the radiating source  20 . In particular, the oscillation circuit module  61  of the anti-interference circuit  60  comprises a triode circuit processor  611 , an inductor  612 , a first resistor  613 , a second resistor  614 , a first capacitor  615 , a second capacitor  616 , a third capacitor  617 , a fourth capacitor  618  and a fifth capacitor  619 . The triode circuit processor  611  comprises a first connection terminal  6111 , a second connection terminal  6112 , and a third connection terminal  6113 . One end of the inductor  612  is electrically connected to a power source VCC  63  while another end of the inductor  612  is electrically connected to the first connection terminal  6111  of the triode circuit processor  611 . In other words, the first connection terminal  6111  of the triode circuit processor  611  is electrically connected to a power source VCC  63  through the inductor  612 . One end of the first resistor  613  is electrically connected to the first connection terminal  6111  of the triode circuit processor  611  while another end of the first resistor  613  is electrically connected to the second connection terminal  6112  of the triode circuit processor  611 . One end of the first capacitor  615  is electrically connected to the second connection terminal  6112  of the triode circuit processor  611  while another end of the first capacitor  615  is electrically connected to one end of the second capacitor  616 . Another end of the second capacitor  616  is electrically connected to a ground point  64 , such that the second connection terminal  6112  is grounded. In other words, the second connection terminal  6112  of the triode circuit processor  611  is grounded. One end of the third capacitor  617 is electrically connected to the first connection terminal  6111  of the triode circuit processor  611  while another end of the third capacitor  617  is electrically connected to the third connection terminal  6113  of the triode circuit processor  611 . One end of the second resistor  614  is electrically connected to the third connection terminal  6113  of the triode circuit processor  611  while another end of the second resistor  614  is electrically connected to the ground point  64 . One end of the fourth capacitor  618  is electrically connected to the third connection terminal  6113  of the triode circuit processor  611  while another end of the fourth capacitor  618  is electrically connected to one end of the fifth capacitor  619 . Another end of the fifth capacitor  619  is electrically connected to the feed point  22  of the radiating source  20 . In other words, the feed point  22  of the radiating source  20  is directly and electrically connected to the third connection terminal  6113  of the triode circuit processor  611 . Accordingly, when the reference ground  10  is grounded (i.e. the oscillation circuit module  61  has the zero reference potential), and when the feed point  22  is electrically connected to the oscillation circuit module  61 , the antenna body can receive the excitation current to generate the electromagnetic wave signal. 
     Accordingly, comparing with the conventional oscillation circuit, the first terminal of the triode circuit provides the excitation electrical signal to the feed point  22  of the radiating source  20 . As the current is weak, it is difficult to match with the low impendence of the antenna, so that the conventional antenna cannot be excited. It is worth mentioning that the triode circuit processor  611  of the present invention can be a MOS transistor, wherein the third connection terminal  6113  of the triode circuit processor  611  can be the electrode source of the MOS transistor. In other words, the feed point  22  of the radiating source  20  is directly and electrically connected to the electrode source of the MOS transistor. Therefore, the anti-interference circuit  60  can provide a relatively large excitation current to the feed point  22  of the radiating source  20  and to lower the low impedance of the antenna. In another embodiment, the triode circuit processor  611  can be a triode, wherein the third connection terminal  6113  of the triode circuit processor  611  can be the emitter of the triode. In other words, the feed point  22  of the radiating source  20  is directly and electrically connected to the emitter of the triode. Therefore, the anti-interference circuit  60  can provide a relatively large excitation current to the feed point  22  of the radiating source  20  and to lower the low impedance of the antenna. 
     It should be understood that the present invention provides the excitation current to the radiating source  20  through the third connection terminal  6113  of the triode circuit processor  611 . The third connection terminal  6113  of the triode circuit processor  611  is the output terminal thereof. In other words, the current is output at the third connection terminal  6113  of the triode circuit processor  611  to lower the impedance of the oscillation circuit module  61 , so as to provide a relatively large excitation current to the feed point  22  of the radiating source  20  and to lower the low impedance of the antenna. Accordingly, the configuration of the anti-interference circuit  60  should not be limited in the present invention. 
     The mixing detection circuit module  62  comprises a first diode  621  and a second diode  622 , wherein one end of the first diode  621  and one end of the second diode  622  are connected to a signal output terminal  65 . Another end of the first diode  621  and another end of the second diode  622  are connected to the ground point  64 . 
     Accordingly, the connection among the anti-interference circuit  60 , the radiating source  20 , and the reference ground  10  prevents any mutual affect among the direct current potentials of the oscillation circuit module  61  of the anti-interference circuit  60  , the mixing detection circuit module  62  of the anti-interference circuit  60 , and the analog circuit  70 , so as to ensure the stability and reliability of the antenna. Thus, by configuring the anti-interference circuit  60  to configure the fifth capacitor  619  between the third capacitor  617  and the fourth capacitor  618  of the oscillation circuit module  61  and the feed point  22  of the radiating source  20 , the oscillation circuit module  61 , the mixing detection circuit module  62 , and the feed point  22  of the radiating source  20  can be capacitive coupling with each other. Therefore, the mixing detection circuit module  62  adapts the low impedance output of the oscillation circuit module  61  and the low impedance of the antenna with respect to the ground, so as to effective suppress the differential interference from the coupling and the common interference from the reception of the antenna. In other words, the anti-interference ability of the antenna will be enhanced. 
     In addition, according to the antenna of the present invention, the inductor  612  is provided between the first connection terminal  6111  of the triode circuit processor  611  and the power source VCC  63  to further reduce the interference of the oscillation circuit module  61 , so as to provide the suitable excitation current to match with the low impedance antenna. 
     According to the preferred embodiment, the radiating connection point  21  of the radiating source  20  is electrically connected to the reference ground connection point  11  of the reference ground  10  to electrically ground the radiating connection point  21  of the radiating source  20  at the ground point  64 . Through such connection, after the excitation current is received at the feed point  22  of the radiating source  20 , the inductance characteristics will be generated between the radiating connection point  21  and the feed point  22  of the radiating source  20  to provide a predetermined impedance, such that the antenna is easily initialized at a polarization direction to stably generate the radiate energy in a radial and outward direction. At the same time, the inductance characteristics will be generated between the radiating connection point  21  and the feed point  22  to have a relatively low impedance. Therefore, the bandwidth of the antenna will be narrowed down to prevent the electromagnetic wave signals received or generated by the antenna from being interfered by the nearby electromagnetic radiation frequency or the stray radiation frequency, so as to enhance the anti-interference ability of the antenna. 
     In other words, when the impedance of the antenna body is reduced, the corresponding bandwidth thereof will be narrowed, such that the frequency of the electromagnetic wave signal generated by the antenna body will be more concentrated within the bandwidth. As a result, the electromagnetic wave signal by the antenna body will prevent being interfered by the nearby electromagnetic radiation frequency or the stray radiation frequency, so as to enhance the anti-interference ability of the antenna. It is worth mentioning that when the impedance of the antenna body is reduced, the amount of the excitation current will be relatively increased. The impedance of the oscillation circuit module  61  will be further reduced to provide the excitation current to the antenna body. 
     Therefore, by grounding the radiating source  20  and by configuring the distance between the radiating connection point  21  and the feed point  22  of the radiating source  20  being greater than or equal to  1 / 64 k, the portion between the feed point  22  of the radiating source  20  and the reference ground connection point  11  will be inducted under high frequency excitation current, i.e. the element LOb of the analog circuit  70 . As a result, the impedance of the antenna body is reduced when the antenna body is excited by the excitation current to generate the electromagnetic wave signal, especially when the reference ground connection point  11  is provided at the physical center point of the radiating source  20 . 
     It is worth mentioning that an inductor can be provided for the antenna body, wherein one end of the inductor is connected to the reference ground connection point  11  and another end of the inductor is grounded. Therefore, the distance between the radiating connection point  21  and the feed point  22  of the radiating source  20  will not be limited. Since the reference ground  10  is grounded, the ground end of the inductor can be grounded by connecting to the reference ground  10 . 
       FIGS. 9 and 10  illustrate a second embodiment of the present invention as an alternative mode thereof, wherein the antenna comprises a reference ground  10 A, two radiating sources  20 A, and an elongated connector  60 A. The two radiating sources  20 A are located adjacent to each other and are electrically connected by the elongated connector  60 A. The elongated connector  60 A is embodied as a micro-connection strip. A radiating clearance  30 A is formed at each of the radiating sources  20 A and the reference ground  10 A. 
     Accordingly, the reference ground  10 A has a first side  101 A and an opposed second side  102 A, wherein the radiating sources  20 A are provided at the first side  101 A of the reference ground  10  A. 
     As shown in  FIGS. 9 and 10  , each of the radiating sources  20 A has at least a radiating connection point  21 A. The reference ground  10 A has at least two reference ground connection points  11  A. The radiating connection points  21 A of the radiating sources  20 A are electrically connected to the reference ground connection points  11 A of the reference ground  10 A respectively. One of the radiating sources  20 A has a feed point  22 A while another radiating source  20 A does not contain any feed point. For easy understanding, the radiating source  20 A with the feed point  22 A becomes a primary radiating source  201 A and the radiating source  20 A without the feed point  22 A becomes a secondary radiating source  202 A as shown in  FIGS. 9 and 10 . In other words, the primary radiating source  201 A and the secondary radiating source  202 A are located adjacent to each other. The radiating clearance  30 A is formed between the reference ground  10 A and each of the primary radiating source  201 A and the secondary radiating source  202 A. Two ends of the elongated connector  60 A are electrically connected to the primary radiating source  201 A and the secondary radiating source  202 A respectively. 
     The excitation current is received at the feed point  22 A of the primary radiating source  201 A. After the excitation current is received at the feed point  22 A of the primary radiating source  201 A, the excitation current passes through the elongated connector  60 A to the secondary radiating source  202 A. At this time, the antenna is initialized at polarization direction to stably generate the radiate energy in a radial and outward direction through the radiating clearance  30 A. Since the primary radiating source  201 A and the secondary radiating source  202 A are electrically connected with the radiating connection point  21  and the feed point  22  to provide a predetermined impedance after the excitation current is received at the feed point  22 A of the primary radiating source  201 A and is sent to the secondary radiating source  202 A through the elongated connector  60 A. Therefore, the bandwidth of the antenna will be narrowed down to prevent the electromagnetic wave signals received or generated by the antenna from being interfered by the nearby electromagnetic radiation frequency or the stray radiation frequency, so as to enhance the anti-interference ability of the antenna. 
     Preferably, a distance between the feed point  22 A and the radiating connection point  21 A of the primary radiating source  201 A is greater than or equal to 1/64λ, where λ is the wavelength of the electromagnetic wave signal received or generated by the antenna. Under the excitation of the electromagnetic wave signal, the electromagnetic wave signal will generate the inductance characteristics between the feed point  22 A and the radiating connection point  21 A of the primary radiating source  201 A. Since the feed point  22 A of the primary radiating source  201 A is deviated from the physical center point thereof, the intensity required for the excitation current of the antenna to the electromagnetic wave signal will be substantially reduced. As a result, once the excitation current is received by the feed point  22 A of the primary radiating source  201 A, the antenna is easily initialized at a polarization direction. 
     Preferably, the radiating connection point  21 A of the primary radiating source  201 A is defined as the physical center point thereof. In other words, the physical center point of the primary radiating source  201 A is electrically connected to the reference ground  10 A to ground the primary radiating source  201 A. Therefore, a distance between the periphery of primary radiating source  201 A and the radiating connection point  21 A thereof is preset. Correspondingly, the radiating connection point  21 A of the secondary radiating source  202 A is defined as the physical center point thereof, wherein the physical center point of the secondary radiating source  202 A is electrically connected to the reference ground  10 A, such that a distance between the periphery of secondary radiating source  202 A and the radiating connection point  21 A thereof is preset. Therefore, the antenna can evenly and stably generate the radiate energy via the primary radiating source  201 A and the secondary radiating source  202 A in a radial and outward direction after the initial polarization direction is generated. Under the excitation of the electromagnetic wave signal and through the electrical connection among the reference ground  10 A and the physical center points of the primary radiating source  201 A and the secondary radiating source  202 A, when the excitation current is received by the feed point  22 A of the primary radiating source  201 A to the secondary radiating source  202 A through the elongated connector  60 A, the antenna can evenly and stably generate the radiate energy via the primary radiating source  201 A and the secondary radiating source  202 A in a radial and outward direction. At the same time, the inductance characteristics will be generated between the feed point  22 A and the radiating connection point  21 A of the primary radiating source  201 A and the inductance characteristics will be generated between the elongated connector  60 A and the radiating connection point  21 A of the secondary radiating source  202 A to lower the impedance of the antenna. Therefore, the bandwidth of the antenna will be narrowed down to prevent the electromagnetic wave signals received or generated by the antenna from being interfered by the nearby electromagnetic radiation frequency or the stray radiation frequency, so as to enhance the anti-interference ability of the antenna. 
     As shown in  FIGS. 9 and 10 , the antenna further comprises at least two electrical connection elements  40 A, wherein one of the electrical connection elements  40 A has two terminal ends electrically connecting with the radiating connection point  21 A of the primary radiating source  201 A and one of the reference ground connection points  11 A of the reference ground  10 A respectively. Therefore, the electrical connection element  40 A forms an electrical connection media to electrically connect the primary radiating source  201 A and the reference ground  10 A with each other so as to ground the primary radiating source  201  A. Another electrical connection element  40 A has two terminal ends electrically connecting with the radiating connection point  21 A of the secondary radiating source  202 A and another reference ground connection point  11 A of the reference ground  10 A respectively. Therefore, the electrical connection element  40 A forms an electrical connection media to electrically connect the secondary radiating source  202 A and the reference ground  10 A with each other so as to ground the secondary radiating source  202 A. 
     Preferably, there are at least two radiating connection points  21 A provided by at least one of the primary radiating source  201 A and the secondary radiating source  202 A. In one embodiment, for example, the primary radiating source  201 A provides two or more radiating connection points  21 A while the secondary radiating source  202 A provides one radiating connection point  21 A. The physical center point of the primary radiating source  201 A is surrounded by the radiating connection points  21 A of the primary radiating source  201 A. The radiating connection point  21 A of the secondary radiating source  202 A is the physical center point thereof. In another embodiment, the primary radiating source  201 A provides one radiating connection point  21 A while the secondary radiating source  202 A provides two or more radiating connection point  21 A. The radiating connection point  21 A of the primary radiating source  201 A is the physical center point thereof. The physical center point of the secondary radiating source  202 A is surrounded by the radiating connection points  21 A of the secondary radiating source  202 A. In another further embodiment, the primary radiating source  201 A provides two or more radiating connection points  21 A while the secondary radiating source  202 A provides two or more radiating connection point  21 A. The physical center point of the primary radiating source  201 A is surrounded by the radiating connection points  21 A of the primary radiating source  201  A. The physical center point of the secondary radiating source  202 A is surrounded by the radiating connection points  21 A of the secondary radiating source  202 A. 
     As shown in  FIGS. 9 and 10 , the antenna further comprises a shield member  50 A coupled at the reference ground  10 A at the second side  102 A thereof. 
       FIGS. 11 and 12  illustrate a third embodiment of the present invention as another alternative mode thereof, wherein the antenna comprises a reference ground  10 B, four radiating sources  20 B, and three elongated connectors  60 B. The reference ground  10 B has a first side  101 B and an opposed second side  102 B. The four radiating sources  20 B are formed in pair and are located adjacent to each other on the first side  101 B of the reference ground  10 B. The elongated connector  60 A is embodied as a micro-connection strip. A radiating clearance  30 B is formed at each of the radiating sources  20 B and the reference ground  10 A. The first elongated connectors  60 B has two ends connecting to two adjacent radiating sources  20 B in pair. The second elongated connector  60 B has two ends connecting to two adjacent radiating sources  20 B in another pair. The third elongated connector  60 B has two ends connecting between the first and second elongated connectors  60 B. 
     According to the preferred embodiment, the four radiating sources  20 B are defined as a first radiating source  210 B, a second radiating source  220 B, a third radiating source  230 B, and a fourth radiating source  240 B. The first through fourth radiating sources  210 B,  220 B,  230 B,  240 B are orderly located in a clockwise direction. Therefore, the first radiating source  210 B is located adjacent to the second and fourth radiating sources  220 B,  240 B. The third radiating source  230 B is located adjacent to the second and fourth radiating sources  220 B,  240 B. The first radiating source  210 B is located opposite to the third radiating source  230 B. The second radiating source  220 B is located opposite to the fourth radiating source  240 B. In addition, the radiating clearance  30 B is formed between the first radiating source  210 B and the reference ground  10 B. The radiating clearance  30 B is also formed between the second radiating source  220 B and the reference ground  10 B. The radiating clearance  30 B is also formed between the third radiating source  230 B and the reference ground  10 B. The radiating clearance  30 B is also formed between the fourth radiating source  240 B and the reference ground  10 B. As it is mentioned above, the three elongated connectors  60 B are defined as the first elongated connector  61 B, the second elongated connector  62 B, and the third elongated connector  63 B. The two ends of the first elongated connector  61 B are electrically connected to the first and second radiating sources  210 B,  220 B respectively. The two ends of the second elongated connector  62 B are electrically connected to the third and fourth radiating sources  230 B,  240 B respectively. The two ends of the third elongated connector  63 B are electrically connected to the first and second elongated connectors  61 B,  62 B. 
     As shown in  FIGS. 11 and 12 , the first through fourth radiating sources  210 B,  220 B,  230 B,  240 B are correspondingly connected to the reference ground  10 B, wherein when the excitation current is received by the first through fourth radiating sources  210 B,  220 B,  230 B,  240 B, the antenna is initialized at a polarization direction to enable the electromagnetic wave signals received or generated by the antenna. 
     As shown in  FIGS. 11 and 12 , each of the first through fourth radiating sources  210 B,  220 B,  230 B,  240 B has at least a radiating connection point  21 B. The reference ground  10 B has at least four reference ground connection points  11 A electrically connected to the first through fourth radiating sources  210 B,  220 B,  230 B,  240 B respectively. 
     Each of the first through fourth radiating sources  210 B,  220 B,  230 B,  240 B has a feed point  22 B to receive the excitation current. Preferably, a distance between the feed point  22 B and the radiating connection point  21 B of any one of the first through fourth radiating sources  210 B,  220 B,  230 B,  240 B is greater than or equal to 1/64λ, where λ is the wavelength of the electromagnetic wave signal received or generated by the antenna. 
     Under the excitation of the electromagnetic wave signal, the electromagnetic wave signal will generate the inductance characteristics between the feed point  22 B and the radiating connection point  21 B of one of the first through fourth radiating sources  210 B,  220 B,  230 B,  240 B to provide a predetermine of impedance. The antenna is initialized at a polarization direction to stably generate the radiate energy in a radial and outward direction. At the same time, the inductance characteristics will be generated between the feed point  22 B and the radiating connection point  21 B and the inductance characteristics will be generated between the elongated connector  60 A to lower the impedance of the antenna. Therefore, the bandwidth of the antenna will be narrowed down to prevent the electromagnetic wave signals received or generated by the antenna from being interfered by the nearby electromagnetic radiation frequency or the stray radiation frequency, so as to enhance the anti-interference ability of the antenna. 
     Furthermore, the feed point  22 B of the corresponding radiating source  20 B is deviated from a physical center point thereof to lower the amount or intensity of the excitation current for the antenna. In addition, when the excitation current is received by the feed point  22 B of the first radiating source  210 B, the feed point  22 B of the second radiating source  220 B, the feed point  22 B of the third radiating source  230 B, and the feed point  22 B of the fourth radiating source  240 B, the antenna is easily initialized at a polarization direction. 
     Preferably, the feed point  22 B of the first radiating source  210 B is the connection point to connect to the first elongated connector  61 B. The feed point  22 B of the second radiating source  220 B is the connection point to connect to the first elongated connector  61 B. The feed point  22 B of the third radiating source  230 B is the connection point to connect to the second elongated connector  62 B. The feed point  22 B of the fourth radiating source  240 B is the connection point to connect to the second elongated connector  62 B. 
     Furthermore, the antenna further comprises an antenna feed point  70 B electrically connected to the third elongated connector  63 B. When the excitation current is received at the antenna feed point  70 B of the antenna, it passes through the third elongated connector  63 B to the feed points  22 B of the first through fourth radiating sources  210 B,  220 B,  230 B,  240 B via the first and second elongated connectors  61 B,  62 B. Therefore, the bandwidth of the antenna will be narrowed down to prevent the electromagnetic wave signals received or generated by the antenna from being interfered by the nearby electromagnetic radiation frequency or the stray radiation frequency, so as to enhance the anti-interference ability of the antenna. 
     In addition, when the first radiating source  210 B has one radiating connection point  21 B, the radiating connection point  21 B of the first radiating source  210 B is defined as the physical center point thereof. When the first radiating source  210 B has two or more radiating connection points  21 B, the physical center point of the first radiating source  210 B is surrounded by the radiating connection points  21 B thereof. When the second radiating source  220 B has one radiating connection point  21 B, the radiating connection point  21 B of the second radiating source  220 B is defined as the physical center point thereof. When the second radiating source  220 B has two or more radiating connection points  21 B, the physical center point of the second radiating source  220 B is surrounded by the radiating connection points  21 B thereof. When the third radiating source  230 B has one radiating connection point  21 B, the radiating connection point  21 B of the third radiating source  230 B is defined as the physical center point thereof. When the third radiating source  230 B has two or more radiating connection points  21 B, the physical center point of the third radiating source  230 B is surrounded by the radiating connection points  21 B thereof. When the fourth radiating source  240 B has one radiating connection point  21 B, the radiating connection point  21 B of the fourth radiating source  240 B is defined as the physical center point thereof When the fourth radiating source  240 B has two or more radiating connection points  21 B, the physical center point of the fourth radiating source  240 B is surrounded by the radiating connection points  21 B thereof. 
     As shown in  FIGS. 11 and 12 , the antenna further comprises at least four electrical connection elements  40 B, wherein at least one of the electrical connection elements  40 B has two terminal ends electrically connecting with the radiating connection point  21 B of the first radiating source  210 B and the reference ground connection point  11 B of the reference ground  10 B respectively, so as to electrically connect the first radiating source  210 B with the reference ground  10 B. At least one of the electrical connection elements  40 B has two terminal ends electrically connecting with the radiating connection point  21 B of the second radiating source  220 B and the reference ground connection point  11 B of the reference ground  10 B respectively, so as to electrically connect the second radiating source  220 B with the reference ground  10 B. At least one of the electrical connection elements  40 B has two terminal ends electrically connecting with the radiating connection point  21 B of the third radiating source  230 B and the reference ground connection point  11 B of the reference ground  10 B respectively, so as to electrically connect the third radiating source  230 B with the reference ground  10 B. At least one of the electrical connection elements  40 B has two terminal ends electrically connecting with the radiating connection point  21 B of the fourth radiating source  240 B and the reference ground connection point  11 B of the reference ground  10 B respectively, so as to electrically connect the fourth radiating source  240 B with the reference ground  10 B. 
     As shown in  FIGS. 11 and 12 , the antenna further comprises a shield member  50 B coupled at the reference ground  10 B at the second side  102 B thereof. 
     It is appreciated that different components (elements) as described in the above first, second, third and fourth naming elements should not have any distinguish between different parts, elements, and structures of the present invention. Unless it is specified otherwise, the order or the number of the component should not be limited. Specifically, in this specific example of the antenna shown in  FIGS. 11 and 12 , the first radiating source  210 B, the second radiating source  220 B, the third radiating source  230 B and the fourth radiating source  240 B are only used to describe different locations of the radiation source  20 B at different positions of the present invention, which does not refer to the order or the number of the radiation sources  20 B. 
       FIGS. 13 and 14  illustrate the fourth embodiment of the present invention as another alternative mode thereof, wherein the antenna comprises a reference ground  10 C and at least a radiating source  20 C. The radiating source  20 C is disposed adjacent to the reference ground  10 C to define a radiating clearance  30 C between the radiating source  20 C and the reference ground  10 C. Accordingly, at least one radiating source  20 C is electrically connected to the reference ground  10 C. 
     In particular, the reference ground  10 C has a first side  101 C and an opposed second side  102 C, wherein the radiating source  20 C is disposed at the first side  101 C of the radiating source  20 C. 
     As shown in  FIGS. 13 and 14  , the radiating source  20 C has one radiating connection point  21 C and a feed point  22 C, wherein the radiating connection point  21 C is overlapped with the feed point  22 C. The reference ground  10 C has at least one reference ground connection point  11 C. The antenna further comprises at least an electrical connection element  40 B, wherein the electrical connection element  40 B preferably is an inductor. The electrical connection element  40 C has two terminal ends electrically connecting with the radiating connection point  21 C of the radiating source  20 C and the reference ground connection point  11 C of the reference ground  10 C respectively, so as to electrically connect the radiating source  20 C with the reference ground  10 C via the electrical connection element  40 C. For example, the electrical connection element  40 C, can be, but not limited to, a curved connection type inductor or a threaded connection type inductor. After the excitation current is received at the feed point  22 C of the radiating source  20 C, the antenna is initialized at a polarization direction at the radiating source  20 C to stably generate the radiate energy in a radial and outward direction. Since the radiating source  20 C is electrically connected to the reference ground  10 C by the electrical connection element  40 C, the impedance of the antenna will be lowered after the excitation current is received at the feed point  22 C of the radiating source  20 C. Therefore, the bandwidth of the antenna will be narrowed down to prevent the electromagnetic wave signals received or generated by the antenna from being interfered by the nearby electromagnetic radiation frequency or the stray radiation frequency, so as to enhance the anti-interference ability of the antenna. 
     Alternatively, the radiating source  20 C and the reference ground  10 C are electrically connected with each other via the electrical connection element  40 D, wherein a slot is formed at the reference ground  10 C and a metal layer is formed at a wall of the slot to form a metallization slot as the electrical connection element  40 D to electrically connect the radiating source  20 C with the reference ground  10 C as shown in  FIG. 15 . It is worth mentioning that the feed point of the antenna is electrically connected to the oscillating circuit by the electrical connection element  40 D. 
     According to the preferred embodiment, the present invention further comprises a method of manufacturing the antenna, which comprises the following steps. 
     (a) Form the radiating clearance  30  between the radiating source  20  and the reference ground  10 , wherein the radiating source  20  is spacedly disposed at the first side  101  of the reference ground  10 . 
     (b) Ground the radiating source  20  to form the antenna. 
     Accordingly, in the step (b), the radiating source  20  is electrically connected to the reference ground  10 , such that the radiating source  20  is grounded. 
     It is worth mentioning that the step (b) can be performed prior to the step (a). In other words, the radiating source  20  is electrically connected to the reference ground  10  first and then the radiating source  20  is spacedly retain at the first side  101  of the reference ground  10 . 
     In the step (a), a solid media is placed on the first side  101  of the reference ground  10 , wherein the radiating source  20  is then disposed on the solid media to spacedly retain the radiating source  20  at the reference ground  10  so as to form the radiating clearance  30  between the radiating source  20  and the reference ground  10 . Alternatively, the solid media can be placed at the radiating source  20 , wherein the solid media is then disposed on the first side  101  of the reference ground  10  to spacedly retain the radiating source  20  at the reference ground  10  so as to form the radiating clearance  30  between the radiating source  20  and the reference ground  10 . 
     The present invention further provides an anti-interference method for the antenna which comprises the steps of: grounding the radiating source  20  to reduce an internal impedance of the antenna; and receiving the excitation current at the feed point  22  of the radiating source  20  to narrow the bandwidth of the antenna, such that any interference of electromagnetic wave signals received or generated by the antenna of the present invention will be substantially reduced in response to the nearby electromagnetic radiation frequency or stray radiation frequency of the adjacent frequency bands. 
     Referring to  FIGS. 16A to 18 , according to the above first to fourth preferred embodiments of the antenna with anti-interference arrangement, various embodying arrangements and distributions of the at least one radiating connection point  21  and the at least one feed point  22  are illustrated. 
     Referring to  FIG. 18 , the at least one radiating source  20  has at least one feed point  22  and at least one radiating connection point  21 , wherein the at least one feed point  22 , which is arranged to be connected to an excitation current and the oscillating circuit to generate the electromagnetic wave signal (microwave excitation electrical signal), deviates from a physical center point  201  of the at least one radiation source  20 . 
       FIGS. 16A to 16E  are schematic views of the radiating source  20  having a physical center point  201  and illustrating the distribution of one or more feed points  22 . As shown in  FIG. 16A , the feed point  22  is deviated from the physical center point  201  of the radiating source  20  for a predetermined distance. 
     As shown in  FIG. 16B , the antenna provides two feed points  22  arranged in a such a manner that connection lines between the two feed points  22  to the physical center point  201  of the at least one radiating source  20  are perpendicular with each other, i.e. one of the two feed points  22  is arranged on a top side or a bottom side of the physical center point  201  of the radiating source  20  with a predetermined distance therebetween while another one of the two feed points  22  is arranged on a left side or a right side of the physical center point  201  of the radiating source  20  with the same predetermined distance therebetween. 
     As shown in  FIG. 16C , the antenna provides two feed points  22  which are arranged in such a manner that two connection lines between the two feed points  22  to the physical center point  201  of the at least one radiating source  20  are aligned straightly, i.e. the two feed points  22  are arranged on a top side and a bottom side of the physical center point  201  respectively with the same predetermined distance therebetween. 
     As shown in  FIG. 16D , the antenna provides three feed points  22 ,  22 ′,  22 ″, namely a first feed point  22 , a second feed point  22 ′ and a third feed point  22 ″, wherein the first feed point  22  and the second feed point  22 ′ are symmetrically distributed at the radiating source  20  with respect to the physical center point  201  of the radiating source  20 , while a third feed point  22 ″ of the three feed points is arranged in such a manner that a connecting line between the third feed point  22 ″ and the physical center point  201  of the radiating source  20  is perpendicular to a connecting line between the first and the second feed points  22 ,  22 ′ of the three feed points. 
     As shown in  FIG. 16E , the antenna provides four feed points  22 , wherein each of the four feed points  22  is distributed at an equal angle around the physical center point  201  of the at least one radiating source  20  while an equal distance is arranged between each of the four feed points  22  with the physical center point  201  of the at least one radiating source  20  which is electrically connected to the reference ground  10 . 
     Accordingly, according to the present invention, the antenna provides at least two feed points  22  distributed at the at least one radiating source  20  around the physical center point  201  thereof evenly and symmetrically, wherein the radiating source  20  is arranged in such a manner that the at least two feed points  22  are connected for at least two excitation signals with opposite phases so as to enable the at least two feed points  22  to be distributed in symmetrical form with respect to the physical center point  201  to strengthen the zero potential characteristic of the physical center point  201  of the radiating source  20 . 
     Alternatively, the antenna provides at least two feed points  22  distributed at the at least one radiating source  20 , wherein each of the feed points  22  can be fed with excitation signals and emit electromagnetic waves, or receive electromagnetic waves, including the reflecting waves generated and reflected from the object that the emitted electromagnetic waves encountered. 
     In addition, according to the present invention, the at least two feed points  22  of the antenna distributed at the at least one radiating source  20  may include a first feed point  22  configured to emit electromagnetic waves and a second feed point  22  configured to receive electromagnetic waves while the first and second feed points  22  have a predetermined distance therebetween and are preferably arranged perpendicularly. 
     It is appreciated that each of the at least two feed points  22  distributed at the at least one radiating source  20  of the antenna according to the present invention has a polarization direction (i.e. the direction from the feed point  22  to the physical center point  201  of the radiating source  20 ) arranged in perpendicular manner with respect to the physical center point  201  of the radiating source  20 , so as to respectively receive at least two excitation signals with a phase difference of 90 degrees to form the antenna with circular polarization, or alternatively, one of the at least two feed points  22  is configured for receiving excitation signals and another one of the at least two feed points  22  is configured for receiving the corresponding feedback signals so as to enable the antenna achieving a certain degree of isolation of transceiver separation. 
     In view of the various distribution examples as described above and shown in  FIGS. 16A to 16E , the antenna of the present invention provides one or more feed points  22  arranged on the at least one radiating source  20  each having an equal angle around the physical center point  201  of the radiating source  20  and an equal distance from the physical center point  201  of the radiating source  20  and one or more radiating connection points  21  arranged on the radiating source  20  as illustrated in  FIGS. 17A to 17H . 
     Regarding the arrangement of the radiating connecting points  21  of the radiating source  20 , please referring to  FIGS. 17A to 17H , according to the present invention, a same set of radiating connection points  21  are respectively positioned at vertices of a regular polygon having a center point which is the physical center point  201  of the at least one radiating source  20 , wherein the radiating connection points  21  of the same set of radiating connection points are arranged to each having an equal distance with respect to the physical center point  201  of the corresponding radiating source  20  and distributed around the physical center point  201  of the corresponding radiating source  20  with equal angle therebetween. 
     As described in the above preferred embodiments, the at least one radiating source  20  is electrically connected to the reference ground  10  at the radiating connection points  21  of the at least one radiating source  20  so as to feed in excitation signals at the at least one feed point  22  of the at least one radiating source  20 , wherein since the at least one radiating source  20  is electrically connected with the reference ground  10  at the radiating connection points  21 , a zero potential point is formed at the physical center point  201  of the at least one radiating source  20  and an equivalent connection with the reference ground  10  so as to narrowing a bandwidth of the antenna. 
     As shown in  FIG. 17A , a same pair of radiating connection points  21  are symmetrically distributed at the at least one radiating source  20  with respect to the physical center point  201  of the at least one radiating source  20 , wherein in correspondence to connection lines between the same pair of the radiating connection points  21  and a center point which is the physical center point  201  of the at least one radiating source  20 , wherein two connection lines between the two radiating connection points  21  to the physical center point  201  of the at least one radiating source  20  are aligned straightly, i.e. the two radiating connection points  21  are arranged on a top side and a bottom side of the physical center point  201  respectively with the same predetermined distance therebetween. 
     As shown in  FIG. 17B , two pair of radiating connection points  21  are symmetrically distributed on two sides of the physical center point  201  of the at least one radiating source  20  symmetrically, wherein connection lines between the four radiating connection points  21  to the physical center point  201  of the at least one radiating source  20  are aligned straightly, i.e. two radiating connection points  21  are aligned at a top side and two radiating connection points  21  are aligned at a bottom side of the physical center point  201  respectively with the same predetermined distance therebetween. 
       FIGS. 17C to 17H  illustrates further various arrangement of the radiating connection points  21  with respect to the physical center point  201  of the at least one radiating source  20 , wherein the connecting lines between the radiating connection points  21  are merely for illustration purpose to show the equal distance between the two adjacent radiating connection points  21  but not an element actually provided on the radiating source  20 . 
     As shown in  FIG. 17C , the set of radiating connection points  21  has three radiating connection points  21  which are respectively positioned at vertices of a triangle which center point is positioned at the physical center point  201  of the radiating source  20 , wherein the radiating connection points  21  of the same set of three radiating connection points  21  are arranged to each having an equal distance with respect to the physical center point  201  of the corresponding radiating source  20  and distributed around the physical center point  201  of the corresponding radiating source  20  with equal angle therebetween. 
     As shown in  FIG. 17D , the set of radiating connection points  21  has four radiating connection points  21  which are respectively positioned at vertices of a square which center point is positioned at the physical center point  201  of the radiating source  20 , wherein the radiating connection points  21  of the same set of four radiating connection points  21  are arranged to each having an equal distance with respect to the physical center point  201  of the corresponding radiating source  20  and distributed around the physical center point  201  of the corresponding radiating source  20  with equal angle therebetween. 
     As shown in  FIG. 17E , two sets of radiating connection points  21  having eight radiating connection points  21  are respectively positioned at vertices of two squares which center points are positioned at the physical center point  201  of the radiating source  20 , wherein the four radiating connection points  21  of the same set of radiating connection points  21  are arranged to each having an equal distance with respect to the physical center point  201  of the corresponding radiating source  20  and distributed around the physical center point  201  of the corresponding radiating source  20  with equal angle therebetween. 
     As shown in  FIG. 17F , the set of radiating connection points  21  has five radiating connection points  21  which are respectively positioned at vertices of a pentagon which center point is positioned at the physical center point  201  of the radiating source  20 , wherein the radiating connection points  21  of the same set of five radiating connection points  21  are arranged to each having an equal distance with respect to the physical center point  201  of the corresponding radiating source  20  and distributed around the physical center point  201  of the corresponding radiating source  20  with equal angle therebetween. 
     As shown in  FIG. 17G , the set of radiating connection points  21  has six radiating connection points  21  which are respectively positioned at vertices of a hexagon which center point is positioned at the physical center point  201  of the radiating source  20 , wherein the radiating connection points  21  of the same set of six radiating connection points  21  are arranged to each having an equal distance with respect to the physical center point  201  of the corresponding radiating source  20  and distributed around the physical center point  201  of the corresponding radiating source  20  with equal angle therebetween. 
     As shown in  FIG. 17H , two sets of radiating connection points  21  each having three radiating connection points  21  which are respectively positioned at vertices of two triangles which center points are positioned at the physical center point  201  of the radiating source  20 , wherein the radiating connection points  21  of the same set of three radiating connection points  21  are arranged to each having an equal distance with respect to the physical center point  201  of the corresponding radiating source  20  and distributed around the physical center point  201  of the corresponding radiating source  20  with equal angle therebetween. 
     To configure the antenna of the present invention, various configurations of the at least one radiating connection point  21  and at least one feed point  22  can be achieved in combination of the arrangement of the one or more radiating connection points  21  as shown in  FIGS. 17A to 17H  and the one or more feed points  22  as shown in  FIGS. 16A to 16E . In other words, one of the arrangements of the one or more feed points  22  as shown in  FIGS. 16A to 16E  can be configured with one of the arrangements of the one or more radiating connection points  21  as shown in  FIGS. 17A to 17H  to form the desired antenna according to the present invention. For example, as shown in  FIG. 18 , the arrangement of the feed points  22  as shown in  FIG. 16B  is configured with the arrangement of the radiating connection points  21  as shown in  FIG. 17D  to form the radiating source  20  of the antenna, wherein at least one radiating source  20  has two feed point  22  and four radiating connection point  21 , wherein the two feed points  22 , which are arranged to be connected to an excitation current and the oscillating circuit to generate the electromagnetic wave signal (microwave excitation electrical signal), deviates from a physical center point  201  of the radiation source  20 . 
     One skilled in the art will understand that the embodiment of the present invention as shown in the drawings and described above is exemplary only and not intended to be limiting. 
     It will thus be seen that the objects of the present invention have been fully and effectively accomplished. The embodiments have been shown and described for the purposes of illustrating the functional and structural principles of the present invention and is subject to change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.