Abstract:
An antenna apparatus having at least one radiating element. A second radiating element is located opposite a first radiating element. Earth is on the side opposite to the first radiating element with respect to the second radiating element thus opposite to the second radiating element. The second radiating element intervenes between the first radiating element and earth. Either the first or the second radiating element employs a feed terminal.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an antenna apparatus and a communication system. 
     2. Related Art of the Invention 
     First, the configuration of an antenna apparatus according to the prior art will be described with reference to FIG.  20  and FIG.  21 . FIG. 20 is a conceptual diagram providing comparative descriptions of a double-spiral antenna according to the prior art, a circular patch type antenna according to the prior art, and the composite antenna of the present invention. FIG. 21 is a conceptual diagram providing comparative descriptions of the performance characteristics of a double-spiral antenna according to the prior art and the composite antenna of the present invention. 
     First, the configuration of a double-spiral antenna according to the prior art will be described with reference to FIG.  20 . 
     A spiral radiating element  107  has a feed terminal  105  that is given common termination via a sharing unit (not shown) and is connected to a reception input terminal (not shown) and a transmission output terminal (not shown) of a communication apparatus (not shown). The limit of the length L 3  of the spiral radiating element  107  is about ¼ of an electric wave wavelength. Therefore, when 1454 MHz is a resonance frequency, for example, the spiral radiating element  107  is designed so that a length L 3  of the spiral radiating element  107  is approximately 51.6 mm. 
     A circular patch type radiating element  108  is located opposite the spiral radiating element  107 . A limit of the circumferential length L 4  of the circular patch type radiating element  108  is about ½ of the electric wave wavelength. Therefore, when the resonance frequency is 1513 MHz, for example, the circular patch type radiating element  108  is designed so that the circumferential length L 4  of the circular patch type radiating element  108  is approximately 99.1 mm. 
     An inductance  109  is a metal tab for connecting the spiral radiating element  107  and circular patch type radiating element  108 , and stabilizing a potential of the spiral radiating element  107 . 
     A spiral parasitic element  110  is a part that does not have a feed terminal and is fitted parallel to the spiral radiating element  107 . As shown in FIG. 21, the gain of an antenna that has a spiral parasitic element  110  (an antenna that has a double-spiral element), is better than the gain of an antenna that does not have a spiral parasitic element  110  (an antenna that has a single-spiral element). 
     The operation of a double-spiral antenna according to the prior art that has this kind of configuration will now be described with reference to FIG.  20 . As the reception operation of a double-spiral antenna according to the prior art is understood as virtually the opposite of the transmission operation described below, only the transmission operation will be described below. 
     The transmission output terminal (not shown) of a communication apparatus (not shown) performs signal output to the spiral radiating element  107  via the feed terminal  105 . 
     The electric field  155  generated between the spiral radiating element  107  and the circular patch type radiating element  108 , due to the above described signal output from the communication apparatus (not shown), is sent as a transmission electric wave. 
     Next, the configuration of a circular patch type antenna according to the prior art will be described with reference to FIG.  20 . 
     The circular patch type radiating element  108  has a feed terminal  105  that is given common termination via a sharing unit (not shown) and is connected to the reception input terminal (not shown) and transmission output terminal (not shown) of a communication apparatus (not shown). 
     An earth plate  104  is located opposite the circular patch type radiating element  108 . 
     The operation of a circular patch type antenna according to the prior art that has this kind of configuration will now be described with reference to FIG.  20 . As the reception operation of a circular patch type antenna is understood as virtually the opposite of the transmission operation described below, only the transmission operation will be described below. 
     The transmission output terminal (not shown) of the communication apparatus (not shown) performs signal output to the circular patch type radiating element  108  via the feed terminal  105 . 
     An electric field  156  generated between the circular patch type radiating element  108  and the earth plate  104 , due to the above described signal output from the communication apparatus (not shown), is sent as a transmission electric wave. 
     Incidentally, as shown in FIG. 20, a double-spiral antenna according to the prior art has good gain in the transmission band (1453 MHz to 1465 MHz), but does not have good gain in the reception band (1501 MHz to 1513 MHz). Also, as shown in FIG. 20, a circular patch type antenna according to the prior art has good gain in the reception band (1501 MHz to 1513 MHz), but does not have good gain in the transmission band (1453 MHz to 1465 MHz). 
     Summary of the Invention 
     The present invention has been achieved by taking into account the actual problems described above, and it is an objective of the present invention to provide an antenna apparatus and communication system that enable high gain and an increase in specific-bandwidth to be achieved. 
     An antenna apparatus of the present invention comprises: 
     a first radiating element; 
     a second radiating element located opposite the first radiating element; and 
     an earth on the opposite side to the first radiating element with respect to the second radiating element, and opposite the second radiating,element, 
     wherein the first radiating element or the second radiating element is equipped with a feed terminal, and 
     electric fields are generated at least between the first radiating element and the second radiating element, and between the second radiating element and the earth, and electric wave transmission and reception is performed. 
     An antenna apparatus of the present invention comprises: 
     a first radiating element; 
     a second radiating element located opposite the first radiating element; and 
     a third radiating element on the opposite side to the first radiating element with respect to the second radiating element, and opposite the second radiating element, 
     wherein the first radiating element and the third radiating element are equipped with a feed terminal, and 
     electric fields are generated at least between the first radiating element and the second radiating element, and between the second radiating element and the third radiating element, and electric wave transmission and reception is performed. 
     A communication system of the present invention comprises: 
     an antenna apparatus including: a first radiating element; a second radiating element located opposite the first radiating element; and an earth on the opposite side to the first radiating element with respect to the second radiating element, and opposite the second radiating element, 
     wherein the first radiating element or the second radiating element is equipped with a feed terminal, electric fields are generated at least between the first radiating element and the second radiating element, and between the second radiating element and the earth, and electric wave transmission and reception is performed; and 
     a distributor for connecting the feed terminal to a communication apparatus for linear polarization and/or a communication apparatus for circular polarization. 
     A communication system of the present invention comprises: 
     an antenna apparatus including: a first radiating element; a second radiating element located opposite the first radiating element; and a third radiating element on the opposite side to the first radiating element with respect to the second radiating element, and opposite the second radiating element, 
     wherein the first radiating element and the third radiating element are equipped with a feed terminal, electric fields are generated at least between the first radiating element and the second radiating element, and between the second radiating element and the third radiating element, and electric wave transmission and reception is performed; and 
     a distributor for connecting the feed terminal to a communication apparatus for linear polarization and/or a communication apparatus for circular polarization. 
     As shown in FIG.  20  and FIG. 21, the antenna apparatus of the present invention, for example, uses an electric field which is the composite sum of electric field  155  and electric field  156  as transmission and reception electric waves, and has good gain in both the reception band and the transmission band. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 includes an oblique drawing of an antenna apparatus with dielectric inserted described in embodiment 1 of the present invention (FIG.  1 A), and an oblique drawing of the antenna apparatus with no dielectric inserted (FIG.  1 B); 
     FIG. 2 is a type drawing for explaining a transmission operation of the antenna apparatus described in embodiment 1; 
     FIG. 3 includes an oblique drawing of the antenna apparatus with dielectric inserted described in embodiment 2 of the present invention (FIG.  3 A), and an oblique drawing of the antenna apparatus with no dielectric inserted (FIG.  3 B); 
     FIG. 4 includes an oblique drawing of the antenna apparatus with dielectric inserted described in embodiment 3 of the present invention (FIG.  4 A), and an oblique drawing of the antenna apparatus with no dielectric inserted (FIG.  4 B); 
     FIG. 5 includes an oblique drawing of the antenna apparatus with dielectric inserted described in embodiment 4 of the present invention (FIG.  5 A), and an oblique drawing of the antenna apparatus with no dielectric inserted (FIG.  5 B); 
     FIG. 6 is an oblique drawing of the antenna apparatus described in embodiment 1 of the present invention; 
     FIG. 7 is an oblique drawing of the antenna apparatus described in embodiment 2 of the present invention; 
     FIG. 8 is an oblique drawing of the antenna apparatus described in embodiment 3 of the present invention; 
     FIG. 9 is an oblique drawing of the antenna apparatus described in embodiment 4 of the present invention; 
     FIG. 10 is an oblique drawing of the antenna apparatus described in embodiment 1 of the present invention; 
     FIG. 11 is an oblique drawing of the antenna apparatus described in embodiment 2 of the present invention; 
     FIG. 12 is an oblique drawing of the antenna apparatus described in embodiment 3 of the present invention; 
     FIG. 13 is an oblique drawing of the antenna apparatus described in embodiment 4 of the present invention; 
     FIG. 14 includes an oblique drawing (FIG. 14A) and a front view (FIG. 14B) of the antenna apparatus described in embodiment 5 of the present invention; 
     FIG. 15 includes an oblique drawing (FIG. 15A) and a front view (FIG. 15B) of the antenna apparatus described in embodiment 5 of the present invention; 
     FIG. 16 includes an oblique drawing (FIG. 16A) and cross-sectional drawing (FIG. 16B) of the antenna apparatus described in embodiment 6 of the present invention; 
     FIG. 17 is an oblique drawing of the antenna apparatus described in embodiment 7 of the present invention; 
     FIG. 18 includes an oblique drawing (FIG. 18A) and cross-sectional drawing (FIG. 18B) of the antenna apparatus described in embodiment 8 of the present invention; 
     FIG. 19 includes an oblique drawing (FIG. 19A) and front view (FIG. 19B) of the antenna apparatus described in embodiment 9 of the present invention; 
     FIG. 20 is a conceptual diagram providing comparative descriptions of antennas according to the prior art and the antenna of the present invention; 
     FIG. 21 is a conceptual diagram providing comparative descriptions of the performance characteristics of antennas according to the prior art and the antenna of the present invention; 
     FIG. 22 includes an oblique drawing of the antenna apparatus with dielectric inserted described in embodiment 10 of the present invention (FIG.  22 A), and an oblique drawing of the antenna apparatus with no dielectric inserted (FIG.  22 B); 
     FIG. 23 includes an oblique drawing of the antenna apparatus with dielectric inserted described in embodiment 11 of the present invention (FIG.  23 A), and an oblique drawing of the antenna apparatus with no dielectric inserted (FIG.  23 B); 
     FIG. 24 includes an oblique drawing of the antenna apparatus with dielectric inserted described in embodiment 12 of the present invention (FIG.  24 A), and an oblique drawing of the antenna apparatus with no dielectric inserted (FIG.  24 B); 
     FIG. 25 includes an oblique drawing of the antenna apparatus with dielectric inserted described in embodiment 13 of the present invention (FIG.  25 A), and an oblique drawing of the antenna apparatus with no dielectric inserted (FIG.  25 B); 
     FIG. 26 includes an oblique drawing of the antenna apparatus with dielectric inserted described in embodiment 14 of the present invention (FIG.  26 A), and an oblique drawing of the antenna apparatus with no dielectric inserted (FIG.  26 B); 
     FIG. 27 is a type drawing for explaining the transmission operation of the antenna apparatus in embodiment 14 of the present invention; 
     FIG. 28 includes a schematic drawing for explaining the directivity of the antenna apparatus in embodiments 1 to 13 of the present invention (FIG.  28 A), and a schematic drawing for explaining the directivity of the antenna apparatus in embodiments 14 to 16 of the present invention (FIG.  28 B); 
     FIG. 29 includes an oblique drawing of the antenna apparatus with dielectric inserted described in embodiment 15 of the present invention (FIG.  29 A), and an oblique drawing the antenna apparatus with no dielectric inserted (FIG. 29B; 
     FIG. 30 includes an oblique drawing of the antenna apparatus with dielectric inserted described in embodiment 16 of the present invention (FIG.  30 A), and an oblique drawing of the antenna apparatus with no dielectric inserted (FIG. 30B; and 
     FIG. 31 is a configuration diagram of the communication system described in embodiment 17 of the present invention. 
    
    
     DESCRIPTION OF SYMBOLS 
       101  Linear radiating element 
       102  Dielectric 
       103  Patch type radiating element 
       104  Earth plate 
       105  Feed terminal 
       106  Linear parasitic element 
       107  Spiral radiating element 
       108  Circular patch type radiating element 
       109  Inductance 
       110  Spiral parasitic element 
       201  Earth plate (with finite area) 
       301  Printed circuit board 
       501  Linear radiating element supporting stand 
       502  Patch type radiating element supporting pillar 
       701  Case 
       702  Area above (of case  701 ) 
       703  Edge (of case  701 ) 
       801  Cable earth 
       802  Earth 
       901  Cover 
       1001  Linear radiating element 
       1101  Metal pedestal 
       1201  Feeder line 
       1301  Capacitor 
       2001  First spiral radiating element 
       2002  Second spiral radiating element 
       2003  Circular patch type element 
       2004 ,  2004 ′ Spiral parasitic element 
       2005  Feed terminal 
       2006 ,  2006 ′ Inductance 
       2007  Dielectric 
       2011  Electric field due to first spiral radiating element 
       2012  Electric field due to second spiral radiating element 
       2013  Directivity due to first spiral radiating element 
       2014  Directivity due to second spiral radiating element 
       2021 ,  2021 ′ Capacitor 
       2022 ,  2022 ′ Feed line 
       2031  Mixer 
       2041  Coaxial cable 
       2042  Distributor 
       2043  Communication apparatus for linear polarization 
       2044  Communication apparatus for circular polarization 
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     With reference to the attached drawings, the embodiments of the present invention will be described in detail below. 
     Embodiment 1 
     First, the configuration of the antenna apparatus in embodiment 1 will be described with reference to FIGS. 1A and 1B. As will be mentioned later, in the antenna apparatus shown in FIG. 1A, a dielectric  102  is inserted between a linear radiating element  101  that is rectilinear in shape and a patch type radiating element  103 , whereas a dielectric  102  is not inserted in the antenna apparatus shown in FIG. 1B; the antenna apparatus of the present embodiment below has a configuration in which a dielectric is inserted. 
     The linear radiating element  101  is made of metal, and has a feed terminal  105  that is given common termination via a sharing unit (not shown) and is connected to the reception input terminal (not shown) and transmission output terminal (not shown) of a communication apparatus (not shown). The linear radiating element  101  in embodiment 1 corresponds to the first radiating element of the present invention. 
     The patch type radiating element  103  is made of metal, and is located opposite the linear radiating element  101 . The patch type radiating element  103  in embodiment 1 corresponds to the second radiating element of the present invention. 
     The earth plate  104  is made of metal, and is located on the opposite side to the linear radiating element  101  with respect to the patch type radiating element  103 , and opposite the patch type radiating element  103 . The earth plate  104  is earthed and has an essentially infinite area. The earth plate  104  in embodiment 1 corresponds to the earth of the present invention. 
     The inductance  109  is a metal tab for connecting the linear radiating element  101  and the patch type radiating element  103 , and stabilizing the potential of the linear radiating element  101 . 
     The dielectric  102  is a part formed from ceramic material that is inserted between the linear radiating element  101  and patch type radiating element  103 , and has the function of a spacer. The dielectric  102  also supports the linear radiating element  101 . 
     In an antenna apparatus in which a dielectric  102  is not inserted (see FIG.  1 B), the design parameter standards when the transmission band frequency is 1453 MHz to 1465 MHz and the reception band frequency is 1501 MHz to 1513 MHz are as follows. 
     The limit of the height HI of the linear radiating element  101  with respect to the patch type radiating element  103  is about {fraction (1/20)} of the electric wave wavelength. The limit of the height H 2  of the patch type radiating element  103  with respect to the earth plate  104  is about {fraction (1/60)} of the electric wave wavelength. The limit of the length L 1  of the linear radiating element  101  is about ¼ of the electric wave wavelength. The limit of the circumferential length L 2  of the patch type radiating element  103  is about ½ of the electric wave wavelength. 
     The operation of the antenna apparatus in embodiment 1 that has this kind of configuration will now be described with reference to FIG.  2 . FIG. 2 is a schematic drawing for explaining the transmission operation of the antenna apparatus in embodiment 1. As the reception operation of the antenna apparatus in embodiment 1 is understood as virtually the opposite of the transmission operation described below, only the transmission operation will be described below. 
     The transmission output terminal (not shown) of the communication apparatus (not shown) performs signal output to the linear radiating element  101  via the feed terminal  105 . 
     Due to the above described signal output from the communication apparatus (not shown), an electric field  151  is generated between the linear radiating element  101  and the patch type radiating element  103 . Also, due to the above described signal output from the communication apparatus (not shown), an electric field  152  is generated between the patch type radiating element  103  and the earth plate  104 . 
     The electric field  150 , which is the composite sum of electric field  151  and electric field  152 , is sent as the transmission electric wave. 
     The earth plate  104  in embodiment 1 need not have an essentially infinite area, and as shown in FIG. 6, need only have an area roughly 3 times or more the area of the patch type radiating element  103 . FIG. 6 is an oblique drawing of an antenna apparatus that has an earth plate  201  with a finite area. 
     Also, a printed circuit board  301  such as that shown in FIG. 10 can also be installed between the linear radiating element  101  and the patch type radiating element  103  in embodiment 1, and the linear radiating element  101  can also be formed on the printed circuit board  301 . FIG. 10 is an oblique drawing of an antenna apparatus with a printed circuit board  301  installed. 
     Embodiment 2 
     First, the configuration of the antenna apparatus in embodiment 2 will be described with reference to FIGS. 3A and 3B. In the antenna apparatus shown in FIG. 3A, a dielectric  102  is inserted between a linear radiating element  101  and a patch type radiating element  103 , whereas such a dielectric is not inserted in the antenna apparatus shown in FIG. 3B; the antenna apparatus of the present embodiment below has a configuration in which a dielectric is inserted. 
     The antenna apparatus in embodiment 2 differs from the antenna apparatus in embodiment 1 in being equipped with a linear parasitic element  106  that is rectilinear in shape, described next. 
     The linear parasitic element  106  is a part made of metal that does not have a feed terminal and is fitted parallel to the linear radiating element  101 . As already explained, due to the presence of the linear parasitic element  106 , the gain of the antenna apparatus in embodiment 2 is better than the gain of the antenna apparatus in embodiment 1. 
     In an antenna apparatus in which a dielectric  102  is not inserted (see FIG.  3 B), when the transmission band frequency is 1453 MHz to 1465 MHz and the reception band frequency is 1501 MHz to 1513 MHz, the limit of the gap D 1  between the linear radiating element  101  and the linear parasitic element  106  is about {fraction (1/600)} of the electric wave wavelength. 
     The operation of the antenna apparatus in embodiment 2 that has this kind of configuration is the same as the operation of the antenna apparatus in embodiment 1. 
     The earth plate  104  in embodiment 2 need not have an essentially infinite area, and as shown in FIG. 7, need only have an area roughly 3 times or more the area of the patch type radiating element  103 . FIG. 7 is an oblique drawing of an antenna apparatus that has an earth plate  201  with a finite area. 
     Also, a printed circuit board  301  such as that shown in FIG. 11 can also be installed between the linear radiating element  101  and the patch type radiating element  103  in embodiment 2, and the linear radiating element  101  can also be formed on the printed circuit board  301 . FIG. 11 is an oblique drawing of an antenna apparatus with a printed circuit board  301  installed. 
     Embodiment 3 
     First, the configuration of the antenna apparatus in embodiment 3 will be described with reference to FIGS. 4A and 4B. As will be mentioned later, in the antenna apparatus shown in FIG. 4A, a dielectric  102  is inserted between a spiral radiating element  107  and a circular patch type radiating element  108 , whereas a dielectric  102  is not inserted in the antenna apparatus shown in FIG. 4B; the antenna apparatus of the present embodiment below has a configuration in which a dielectric is inserted. 
     The spiral radiating element  107  is made of metal, and has a feed terminal  105  that is given common termination via a sharing unit (not shown) and is connected to the reception input terminal (not shown) and transmission output terminal (not shown) of a communication apparatus (not shown). The spiral radiating element  107  in embodiment 3 corresponds to the first radiating element of the present invention. 
     The circular patch type radiating element  108  is made of metal, and is located opposite the spiral radiating element  107 . The circular patch type radiating element  108  in embodiment 3 corresponds to the second radiating element of the present invention. 
     The earth plate  104  is made of metal, and is located on the opposite side to the spiral radiating element  107  with respect to the circular patch type radiating element  108 , and opposite the circular patch type radiating element  108 . The earth plate  104  is earthed and has an essentially infinite area. The earth plate  104  in embodiment 3 corresponds to the earth of the present invention. 
     The inductance  109  is a metal tab for connecting the spiral radiating element  107  and the circular patch type radiating element  108 , and stabilizing the potential of the spiral radiating element  107 . 
     The dielectric  102  is a part formed from ceramic material that is inserted between the spiral radiating element  107  and circular patch type radiating element  108 , and has the function of a spacer. The dielectric  102  also supports the spiral radiating element  107 . 
     In an antenna apparatus in which a dielectric  102  is not inserted (see FIG.  4 B), the design parameter standards when the transmission band frequency is 1453 MHz to 1465 MHz and the reception band frequency is 1501 MHz to 1513 MHz are as follows. 
     The limit of the height H 3  of the spiral radiating element  107  with respect to the circular patch type radiating element  108  is about {fraction (1/20)} of the electric wave wavelength. The limit of the height H 4  of the circular patch type radiating element  108  with respect to the earth plate  104  is about {fraction (1/60)} of the electric wave wavelength. The limit of the length L 3  of the spiral radiating element  107  is about ¼ of the electric wave wavelength. The limit of the circumferential length L 4  of the circular patch type radiating element  108  is about ½ of the electric wave wavelength. 
     The operation of the antenna apparatus in embodiment 3 that has this kind of configuration is the same as the operation of the antenna apparatus in embodiment 1. 
     The earth plate  104  in embodiment 3 need not have an essentially infinite area, and as shown in FIG. 8, need only have an area roughly 3 times or more the area of the circular patch type radiating element  108 . FIG. 8 is an oblique drawing of an antenna apparatus that has an earth plate  201  with a finite area. 
     Also, a printed circuit board  301  such as that shown in FIG. 12 can also be installed between the spiral radiating element  107  and the circular patch type radiating element  108  in embodiment 3, and the spiral radiating element  107  can also be formed on the printed circuit board  301 . FIG. 12 is an oblique drawing of an antenna apparatus with a printed circuit board  301  installed. 
     Embodiment 4 
     First, the configuration of the antenna apparatus in embodiment 4 will be described with reference to FIGS. 5A and 5B. In the antenna apparatus shown in FIG. 5A, a dielectric  102  is inserted between a spiral radiating element  107  and a circular patch type radiating element  108 , whereas such a dielectric is not inserted in the antenna apparatus shown in FIG. 5B; the antenna apparatus of the present embodiment below has a configuration in which a dielectric is inserted. 
     The antenna apparatus in embodiment 4 differs from the antenna apparatus in embodiment 3 in being equipped with a spiral parasitic element  110 , described next. 
     The spiral parasitic element  110  is a part made of metal that does not have a feed terminal and is fitted parallel to the spiral radiating element  107 . As already explained, due to the presence of the spiral parasitic element  110 , the gain of the antenna apparatus in embodiment 4 is better than the gain of the antenna apparatus in embodiment 3. 
     In an antenna apparatus in which a dielectric  102  is not inserted (see FIG.  5 B), when the transmission band frequency is 1453 MHz to 1465 MHz and the reception band frequency is 1501 MHz to 1513 MHz, the limit of the gap D 2  between the spiral radiating element  107  and the spiral parasitic element  110  is about {fraction (1/600)} of the electric wave wavelength. 
     The operation of the antenna apparatus in embodiment 4 that has this kind of configuration is the same as the operation of the antenna apparatus in embodiment 3. 
     The earth plate  104  in embodiment 4 need not have an essentially infinite area, and as shown in FIG. 9, need only have an area roughly 3 times or more the area of the circular patch type radiating element  108 . FIG. 9 is an oblique drawing of an antenna apparatus that has an earth plate  201  with a finite area. 
     Also, a printed circuit board  301  such as that shown in FIG. 13 can also be installed between the spiral radiating element  107  and the circular patch type radiating element  108  in embodiment 4, and the spiral radiating element  107  can also be formed on the printed circuit board  301 . FIG. 13 is an oblique drawing of an antenna apparatus with a printed circuit board  301  installed. 
     Embodiment 5 
     First, the configuration of the antenna apparatus in embodiment 5 will be described with reference to FIGS. 14A and 14B. FIG. 14A is an oblique drawing of the antenna apparatus in embodiment 5, and FIG. 14B is a front view of the antenna apparatus in embodiment 5. 
     A linear radiating element supporting stand  501  is installed on a patch type radiating element  103 , and supports a linear radiating element  101 . To prevent the occurrence of disturbance of the electric field, the linear radiating element supporting stand  501  is installed outside the area of opposition  503  of the linear radiating element  101  and the patch type radiating element  103 . 
     A patch type radiating element supporting pillar  502  is installed on the earth plate  104 , and supports the linear radiating element  101 . 
     The linear radiating element supporting stand  501  and the patch type radiating element supporting pillar  502  in embodiment 5 corresponds to the supports of the present invention. 
     The operation of the antenna apparatus in embodiment 5 that has this kind of configuration is the same as the operation of the antenna apparatus in embodiment 1. 
     It is also possible for a linear parasitic element  106  to be mounted parallel to the linear radiating element  101  in embodiment 5, as shown in FIG.  15 . FIG. 15A is an oblique drawing of an antenna apparatus with a linear parasitic element  106  mounted in parallel, and FIG. 15B is a front view of an antenna apparatus with a linear parasitic element  106  mounted in parallel. 
     Embodiment 6 
     First, the configuration of the antenna apparatus in embodiment 6 will be described with reference to FIGS. 16A and 16B. FIG. 16A is an oblique drawing of the antenna apparatus in embodiment 6, and FIG. 16B is a cross-sectional drawing of the antenna apparatus in embodiment 6. The antenna apparatus in embodiment 6 differs from the antenna apparatus that has an earth plate  201  with a finite area in embodiment 1 in being equipped with a case  701 , described next. 
     The case  701  is integrated with the earth plate  201 , and houses the linear radiating element  101  and patch type radiating element  103 . The case  701  has an edge  703 , the area above which  702  is open. The height H 5  of the case  701 , as also shown in FIG. 16B, is virtually equal to the height H 6  of the linear radiating element  101  with respect to the earth plate  104 . 
     The operation of the antenna apparatus in embodiment 6 that has this kind of configuration is the same as the operation of the antenna apparatus in embodiment 1. 
     Embodiment 7 
     First, the configuration of the antenna apparatus in embodiment 7 will be described with reference to FIG.  17 . FIG. 17 is an oblique drawing of the antenna apparatus in embodiment 7. The antenna apparatus in embodiment 7 differs from the antenna apparatus in embodiment 1 in being equipped with a cable earth  801 , described next. 
     The cable earth  801  is a metal tab, earthed by an earth  802 , for stabilizing the potential of the patch type radiating element  103 . The cable earth  801  in embodiment 7 corresponds to the earth position determining tab of the present invention. It is sufficient for the length L 5  from the cable earth  801  to the front end of the linear radiating element  101  to be about ¼ of the electric wave wavelength. That is to say, as the cable earth  801  is fitted, it is sufficient simply to set the length from there to the front end of the linear radiating element  101  to about ¼ of the electric wave wavelength, thus simplifying the manufacture of an antenna apparatus. 
     The operation of the antenna apparatus in embodiment 7 that has this kind of configuration is the same as the operation of the antenna apparatus in embodiment 1. 
     Embodiment 8 
     First, the configuration of the antenna apparatus in embodiment 8 will be described with reference to FIGS. 18A and 18B. FIG. 18A is an oblique drawing of the antenna apparatus in embodiment 8, and FIG. 18B is a cross-sectional drawing of the antenna apparatus in embodiment 8. The antenna apparatus in embodiment 8 differs from the antenna apparatus in embodiment 5 in being equipped with a cover  901 , described next. 
     The cover  901  covers the linear radiating element  101 , patch type radiating element  103 , and earth plate  104 , and is formed from ABS. The size D 3  of the space between the cover  901  and the linear radiating element  101  should preferably be about {fraction (1/60)} of the electric wave wavelength or more; tuning frequency drift is avoided by this means. The cover  901  also protects the linear radiating element  101 , patch type radiating element  103 , and earth plate  104 . 
     The operation of the antenna apparatus in embodiment  8  that has this kind of configuration is the same as the operation of the antenna apparatus in embodiment 5. 
     Embodiment 9 
     First, the configuration of the antenna apparatus in embodiment 9 will be described with reference to FIGS. 19A and 19B. FIG. 19A is an oblique drawing of the antenna apparatus in embodiment 9, and FIG. 19B is a front view of the antenna apparatus in embodiment 9. The antenna apparatus in embodiment 9 differs from the antenna apparatus in embodiment 1 in being equipped with a linear radiating element  1001  that extends beyond the patch type radiating element  103 . 
     The linear radiating element  1001  extends beyond the patch type radiating element  103  as shown in FIG.  19 . For this reason, the electric field  154  described later can be used for electric wave transmission and reception. The linear radiating element  1001  in embodiment 9 corresponds to the first radiating element of the present invention. 
     The operation of the antenna apparatus in embodiment  9  that has this kind of configuration will now be described with reference to FIG.  19 . As the reception operation of the antenna apparatus in embodiment 9 is understood as virtually the opposite of the transmission operation described below, only the transmission operation will be described below. 
     The transmission output terminal (not shown) of the communication apparatus (not shown) performs signal output to the linear radiating element  1001  via the feed terminal  105   
     Due to the above described signal output from the communication apparatus (not shown), an electric field  151  is generated between the linear radiating element  1001  and the patch type radiating element  103 , and an electric field  152  is generated between the patch type radiating element  103  and the earth plate  104 . Also, an electric field  154  is generated between the linear radiating element  1001  and the earth plate  104 . Thus, in embodiment 9, an electric field  154  is also generated between the linear radiating element  1001  and the earth plate  104 . 
     The electric field  153  which is the composite sum of electric field  151 , electric field  152 , and electric field  154 , is sent as the transmission electric wave. 
     Embodiment 10 
     First, the configuration of the antenna apparatus in embodiment 10 will be described with reference to FIGS. 22A and 22B. In the antenna apparatus shown in FIG. 22A, a dielectric  102  is inserted between a spiral radiating element  107  and a circular patch type radiating element  108 , whereas such a dielectric is not inserted in the antenna apparatus shown in FIG. 22B; the antenna apparatus of the present embodiment below has a configuration in which a dielectric is inserted. 
     The antenna apparatus in embodiment 10 differs from the antenna apparatus in embodiment 4 in being equipped with a metal pedestal  1101 , described next. 
     The metal pedestal  1101  is located between the circular patch type radiating element  108  and the earth plate  104 , and is in contact with the earth plate  104  but is not in contact with the circular patch type radiating element  108 . The metal pedestal  101  contacts the earth plate  104  by means of a magnet, etc., and can easily be attached to and detached from the earth plate  104 . The spiral radiating element  107 , spiral parasitic element  110 , circular patch type radiating element  108 , and feed terminal  105  are integrated with the metal pedestal  1101 , and together with the metal pedestal  1101  configure an antenna apparatus that can easily be moved from place to place. (Also, by inserting insulating material between the circular patch type radiating element  108  and the metal pedestal  1101 , the circular patch type radiating element  108  can be kept essentially out of contact with the metal pedestal  1101 .) 
     The metal pedestal  1101  is an electric conductor. Therefore, through the contact between the metal pedestal  1101  and the earth plate  104 , the metal pedestal  1101  functions effectively as an earth for the spiral radiating element  107  and circular patch type radiating element  108 . 
     Here, the side of the dielectric  102  toward the spiral radiating element  107  is in contact with the spiral radiating element  107 , and the side of the dielectric  102  toward the circular patch type radiating element  108  is in contact with the circular patch type radiating element  108 . By inserting insulating material between the spiral radiating element  107  and the circular patch type radiating element  108  in this way, the height of the antenna apparatus is kept low, and the spiral radiating element  107  is conveniently supported. The spiral radiating element  107  and circular patch type radiating element  108  may also be contained within the dielectric  102 . 
     The operation of the antenna apparatus in embodiment 10 that has this kind of configuration is the same as the operation of the antenna apparatus in embodiment 4. 
     Embodiment 11 
     First, the configuration of the antenna apparatus in embodiment 11 will be described with reference to FIGS. 23A and 23B. In the antenna apparatus shown in FIG. 23A, a dielectric  102  is inserted between a spiral radiating element  107  and a circular patch type radiating element  108 , whereas such a dielectric is not inserted in the antenna apparatus shown in FIG. 23B; the antenna apparatus of the present embodiment below has a configuration in which a dielectric is inserted. 
     The antenna apparatus in embodiment 11 differs from the antenna apparatus in embodiment 7 in being equipped with a feeder line  1201 . 
     The feeder line  1201  is a line for extending the feed terminal  105  up to the vicinity of the cable earth  801 . Providing the feeder line  1201  enables the antenna apparatus to be easily connected to the communication apparatus (not shown). 
     When the antenna apparatus is connected to the communication apparatus (not shown) by means of a coaxial cable. (not shown), the cable ground of the coaxial cable is connected to the cable earth  801 , and the coaxial cable signal line is connected to the feed terminal  105 . 
     The operation of the antenna apparatus in embodiment 11 that has this kind of configuration is the same as the operation of the antenna apparatus in embodiment 7. 
     Embodiment 12 
     First, the configuration of the antenna apparatus in embodiment 12 will be described with reference to FIGS. 24A and  24 B. In the antenna apparatus shown in FIG. 24A, a dielectric  102  is inserted between a spiral radiating element  107  and a circular patch type radiating element  108 , whereas such a dielectric is not inserted in the antenna apparatus shown in FIG. 24B; the antenna apparatus of the present embodiment below has a configuration in which a dielectric is inserted. 
     The antenna apparatus in embodiment 12 differs from the antenna apparatus in embodiment 11 in being equipped with a capacitor  1301 . 
     The capacitor  1301  is connected between the feeder line  1201  and the coaxial cable signal line (as described in embodiment 11, the cable ground of the coaxial cable is connected to the cable earth, and the coaxial cable signal line is connected to the feed terminal). By connecting the capacitor, it is possible to cancel the reactance component generated by the feeder line and to measure only the actual impedance component, making it easy to achieve antenna impedance matching. 
     The operation of the antenna apparatus in embodiment 12 that has this kind of configuration is the same as the operation of the antenna apparatus in embodiment 1. 
     Embodiment 13 
     First, the configuration of the antenna apparatus in embodiment 13 will be described with reference to FIGS. 25A and  25 B. In the antenna apparatus shown in FIG. 25A, a dielectric  102  is inserted between a spiral radiating element  107  and a circular patch type radiating element  108 , whereas such a dielectric is not inserted in the antenna apparatus shown in FIG. 25B; the antenna apparatus of the present embodiment below has a configuration in which a dielectric is inserted. 
     The antenna apparatus in embodiment 13 differs from the antenna apparatus in embodiment 11 with respect to equipped position of a cable earth  801  described next. 
     By positioning the cable earth  801  at the same level as the spiral radiating element  107 , it is possible to position the feed section of the feeder line  1201  and the cable earth  801  at the same level. As a result, the part bent at a right angle between the spiral radiating element  107  and the cable earth is eliminated, enabling the current loss due to bending of the element to be made small. 
     The operation of the antenna apparatus in embodiment 13 that has this kind of configuration is the same as the operation of the antenna apparatus in embodiment 11. 
     Embodiment 14 
     First, the configuration of the antenna apparatus in embodiment 14 will be described with reference to FIGS. 26A and 26B. In the antenna apparatus shown in FIG. 26A, a dielectric  2007  is inserted between (1) a first spiral radiating element  2001  and a spiral parasitic element  2004  installed parallel to the first spiral radiating element  2001 , and (2) a second spiral radiating element  2002  and a spiral parasitic element  2004 ′ installed parallel to the second spiral radiating element  2002 , whereas such a dielectric is not inserted in the antenna apparatus shown in FIG. 26B; the antenna apparatus of the present embodiment below has a configuration in which a dielectric is inserted. 
     The first spiral radiating element  2001  and second spiral radiating element  2002  are both made of metal, and have a feed terminal  2005  that is given common termination via a sharing unit (not shown) and is connected to the reception input terminal (not shown) and transmission output terminal (not shown) of a communication apparatus (not shown). 
     Common feeding to the first spiral radiating element  2001  and second spiral radiating element  2002  is performed from the feed terminal  2005 . The second spiral radiating element  2002  is located on the opposite side to the first spiral radiating element  2001  with respect to a circular patch type element  2003  made of metal, and is located opposite the circular patch type element  2003 . 
     The first spiral radiating element  2001  corresponds to the first radiating element of the present invention, and the second spiral radiating element  2002  corresponds to the third radiating element of the present invention. The circular patch type element  2003  corresponds to the second radiating element of the present invention. 
     As in embodiment 1, an inductance  2006  connects the first spiral radiating element  2001  and the circular patch type element  2003 , and an inductance  2006 ′ connects the second spiral radiating element  2002  and the circular patch type element  2003 . These are metal tabs for stabilizing the potential of the first spiral radiating element  2001  and second spiral radiating element  2002 . 
     The dielectric  2007  is a part formed from ceramic material that is inserted between (1) the first spiral radiating element  2001  and the spiral parasitic element  2004  installed parallel to the first spiral radiating element  2001 , and (2) the second spiral radiating element  2002  and the spiral parasitic element  2004 ′ installed parallel to the second spiral radiating element  2002 , and has the function of a spacer. The dielectric  2007  also supports the first spiral radiating element  2001  and second spiral radiating element  2002 . 
     A first feeder line  2022  is connected to the first spiral radiating element  2001 , and a second feeder line  2022 ′ is connected to the second spiral radiating element  2002 ; common feeding to these is performed from the feed terminal  2005 . 
     The operation of the antenna apparatus in embodiment  14  that has this kind of configuration will now be described with reference to FIG.  27 . FIG. 27 is a type drawing for explaining the transmission operation of the antenna apparatus in embodiment 14. As the reception operation of the antenna apparatus in embodiment 14 is understood as virtually the opposite of the transmission operation described below, only the transmission operation will be described below. 
     The communication apparatus (not shown) performs the same kind of signal output as in embodiment 1 to the first spiral radiating element  2001  and the second spiral radiating element  2002  via the feed terminal  2005 . 
     Due to the above described signal output from the communication apparatus (not shown), an electric field  2011  is generated between the first spiral radiating element  2001  and the circular patch type element  2003 . Also, due to the above described signal output from the communication apparatus (not shown), an electric field  2012  is generated between the second spiral radiating element  2002  and the circular patch type element  2003 . However, as, unlike embodiment 1, there is no earth opposite the circular patch type element  2003 , there is no electric field radiated from the circular patch type element  2003 . 
     In this way the generated electric fields  2011  and  2012  are combined and sent as the transmission electric wave. 
     Here, the directivity of the antenna apparatus of embodiment 14 will be described using FIGS. 28A and 28B. FIG. 28A is a schematic drawing for explaining the directivity of the antenna apparatus in embodiments 1 to 13, and FIG. 28B is a schematic drawing for explaining the directivity of the antenna apparatus in embodiments 14 to 16. 
     Due to electric field  2011  (see FIG.  27 ), hemispherical directivity  2013  (see FIGS. 28A and 28B) is obtained, and, since the directivity  2014  (see FIG. 28B) obtained due to the electric field  2012  (see FIG. 27) between the second spiral radiating element  2002  and the circular patch type element  2003  is also hemispherical, the antenna directivity obtained as a combination of these consists of directivity  2013  together with directivity  2014 , forming a sphere as shown in FIG.  28 B. As a result, it is possible to realize an antenna apparatus that has high gain in all the directions from which electric waves arrive. 
     Embodiment 15 
     First, the configuration of the antenna apparatus in embodiment 15 will be described with reference to FIG.  29 . In the antenna apparatus shown in FIG. 29A, a dielectric  2007  is inserted between (1) a first spiral radiating element  2001  and a spiral parasitic element  2004  installed parallel to the first spiral radiating element  2001 , and (2) a second spiral radiating element  2002  and a spiral parasitic element  2004 ′ installed parallel to the second spiral radiating element  2002 , whereas such a dielectric is not inserted in the antenna apparatus shown in FIG. 29B; the antenna apparatus of the present embodiment below has a configuration in which a dielectric is inserted. 
     The antenna apparatus in embodiment 16 differs from the antenna apparatus in embodiment 14 in being equipped with capacitors  2021  and  2021 ′, described next. 
     Capacitor  2021  is connected to the first feeder line  2022  on the first spiral radiating element  2001  side, and capacitor  2021 ′ is connected to the second feeder line  2022 ′ on the second spiral radiating element  2002  side. By connecting the capacitors, it is possible to cancel the reactance component generated by the feeder line and to measure only the actual impedance component, making it easy to achieve antenna impedance matching. 
     The operation of the antenna apparatus in embodiment 16 that has this kind of configuration is the same as the operation of the antenna apparatus in embodiment 14. 
     Embodiment 16 
     First, the configuration of the antenna apparatus in embodiment 16 will be described with reference to FIG.  30 . In the antenna apparatus shown in FIG. 30A, a dielectric  2007  is inserted between (1) a first spiral radiating element  2001  and a spiral parasitic element  2004  installed parallel to the first spiral radiating element  2001 , and (2) a second spiral radiating element  2002  and a spiral parasitic element  2004 ′ installed parallel to the second spiral radiating element  2002 , whereas such a dielectric is not inserted in the antenna apparatus shown in FIG. 30B; the antenna apparatus of the present embodiment below has a configuration in which a dielectric is inserted. 
     The antenna apparatus in embodiment 16 differs from the antenna apparatus in embodiment 14 in being equipped with a mixer  2031 , described next. 
     The mixer  2031  is connected between a first feeder line  2032  on the first spiral radiating element  2001  side and a second feeder line  2033  on the second spiral radiating element  2002  side, and is means for performing feeding from the feed terminal  2005  via the mixer  2031 . By means of the mixer  2031 , the signal on the first spiral radiating element  2001  side and the signal on the second spiral radiating element  2002  side are separated, and the degree of separation of the first spiral radiating element  2001  and the second spiral radiating element  2002  is improved. By this means, it is possible to eliminate mutual influence between the first spiral radiating element  2001  and the second spiral radiating element  2002 . 
     The operation of the antenna apparatus in embodiment 16 that has this kind of configuration is the same as the operation of the antenna apparatus in embodiment 14. 
     Embodiment 17 
     First, the configuration of the communication system in embodiment 17 will be described with reference to FIG.  31 . 
     Here, a coaxial cable  2041  is connected to the antenna apparatus in embodiment 13. The coaxial cable  2041  connects the antenna apparatus to a communication apparatus for linear polarization  2043  and a communication apparatus for circular polarization  2044  via a distributor  2042 ; the antenna apparatus shown in FIG. 31 is the antenna apparatus in embodiment  13  (but with the dielectric not shown), and as described above, the cable ground of the coaxial cable is connected to the cable earth  801 , and the coaxial cable signal line is connected to the feed terminal  105 . 
     The antenna apparatus connected to the coaxial cable  2041  may be the antenna apparatus in any of the above described embodiments, and, as described above, is an antenna apparatus with hemispherical directivity in embodiments 1 to 13, or with spherical directivity in embodiments 14 to 16. 
     The possession of hemispherical or spherical directivity makes it possible to receive both electric waves from the ground and electric waves from an artificial satellite (the antenna apparatus in embodiment 13 that has hemispherical directivity is provided with transmission and reception capability for both the linear polarization used in ground communication and the circular polarization used in communication with an artificial satellite, and an antenna apparatus that has spherical directivity (such as the antenna apparatus in embodiment 14) is also provided with transmission and reception capability for both linear polarization and circular polarization). 
     By using the configuration shown in embodiment 17, both a communication apparatus that receives electric waves from the ground and a communication apparatus that receives electric waves from an artificial satellite can be used simultaneously with a single antenna apparatus, enabling the configuration of a communication system to be simplified. 
     The feed terminal in the present invention need not be provided on the first radiating element as in embodiments 1 to 13, but may instead be provided on the second radiating element. 
     Also, the inductance in the present invention is provided in the above described embodiments, but this is not a limitation, and it need not be provided. However, in a case where, for example, the inductance  109  is not provided, the limit of the length L 1  of the linear radiating element  101 , and the limit of the length L 3  of the spiral radiating element  107 , are both about ½ of the electric wave wavelength. 
     Also, the dielectric in the present invention need not be formed from ceramic material as in the above described embodiments, but may instead be formed from Dupont, Teflon, epoxy resin, ABS, etc. Further, the dielectric in the present invention is inserted, in the above described embodiments, only between the first radiating element and second radiating element of the present invention, but this is nota limitation, and, for example, it may instead (1) be inserted so that the first radiating element and second radiating element are contained therein, or (2) be inserted so that the first radiating element and third radiating element are contained therein, or (3) be inserted between the first radiating element and second radiating element and/or between the second radiating element and third radiating element, or (4) not be inserted. However, a lower antenna apparatus height is realized by inserting a dielectric with a high dielectric constant. 
     Also, the cover in the present invention need not be formed from ceramic material as in the above described embodiments, but may instead be formed from Dupont, Teflon, epoxy resin, ABS, etc. 
     Also, the first radiating element and third radiating element in the present invention are both spiral in shape in above described embodiments 14 to 16, but this is not a limitation, and instead, for example, (1) both may be linear in shape, or (2) the first radiating element may be linear in shape while the third radiating element is spiral in shape. 
     Also, the first radiating element and third radiating element in the present invention are each provided with a parallel spiral parasitic element in above described embodiments 14 to 16, but this is not a limitation, and instead, for example, (1) neither may be provided with a parallel spiral parasitic element, or (2) only the first radiating element may be provided with a parallel spiral parasitic element. 
     Also, in above described embodiments 14 to 16, a first feeder line is provided-for the first radiating element in the present invention, a second feeder line is provided for the second radiating element in the present invention, and common feeding is performed for the first feeder line and the second feeder line, but this is not a limitation, and instead, for example, it is possible (1) for the first feeder line and/or second feeder line not to be provided, and feeding to be performed directly, or (2) for feeding to be performed independently to the first feeder line and the second feeder line regardless of whether or not feeder lines are provided. 
     Also, the pedestal in the present invention is an electric conductor in above described embodiment 10, but this is not a limitation, and it need not be an electric conductor. 
     Also, the reactance element in the present invention is a capacitor in the above described embodiments, but this is not a limitation, and it may instead be a coil, etc. 
     As is clear from the above descriptions, a first present invention corresponding to claim  1  can provide an antenna apparatus characterized by realizing high gain and an increase in specific bandwidth. 
     A second present invention corresponding to claim  2  can provide an antenna apparatus characterized by having stable operation, in addition to the above described effects. 
     A third present invention corresponding to claim  3  can provide an antenna apparatus characterized by having a simple structure, in addition to the above described effects. 
     A fourth present invention corresponding to claim  4  can provide an antenna apparatus characterized by realizing high gain, in addition to the above described effects. 
     A fifth present invention corresponding to claim  5  can provide an antenna apparatus characterized by having a simple structure, in addition to the above described effects. 
     A sixth present invention corresponding to claim  6  can provide an antenna apparatus characterized by realizing high gain, in addition to the above described effects. 
     A seventh present invention corresponding to claim  7  can provide an antenna apparatus characterized by realizing a low apparatus height, in addition to the above described effects. 
     An eighth present invention corresponding to claim  8  can provide an antenna apparatus characterized by realizing a small apparatus size, in addition to the above described effects. 
     A ninth present invention corresponding to claim  9  can provide an antenna apparatus characterized by realizing compactness of the apparatus, in addition to the above described effects. 
     A tenth present invention corresponding to claim  10  can provide an antenna apparatus characterized by having a stable structure, in addition to the above described effects. 
     An eleventh present invention corresponding to claim  11  can provide an antenna apparatus characterized by not requiring a separate case, in addition to the above described effects. 
     A twelfth present invention corresponding to claim  12  can provide an antenna apparatus characterized by the fact that manufacture is simple, in addition to the above described effects. 
     A thirteenth present invention corresponding to claim  13  can provide an antenna apparatus characterized by little noise and by having good durability, in addition to the above described effects. 
     A fourteenth present invention corresponding to claim  14  can provide an antenna apparatus characterized by improving simplicity of setting the apparatus, in addition to the above described effects. 
     A fifteenth present invention corresponding to claim  15  can provide an antenna apparatus characterized by having stable operation, in addition to the above described effects. 
     A sixteenth present invention corresponding to claim  16  can provide an antenna apparatus characterized by greater simplicity of performance adjustment in manufacture, in addition to the above described effects. 
     A seventeenth present invention corresponding to claim  17  can provide an antenna apparatus characterized by realizing high gain, in addition to the above described effects. 
     An eighteenth present invention corresponding to claim  18  can provide an antenna apparatus characterized by having high gain in all directions three-dimensionally, in addition to the above described effects. 
     A nineteenth present invention corresponding to claim  19  can provide an antenna apparatus characterized by a small difference in gain according to direction, and stable high gain in all directions, in addition to the above described effects. 
     A twentieth present invention corresponding to claim  20  can provide an antenna apparatus characterized by realizing high gain, in addition to the above described effects. 
     A twenty-first present invention corresponding to claim  21  can provide an antenna apparatus characterized by realizing a low apparatus height, in addition to the above described effects. 
     A twenty-second present invention corresponding to claim  22  can provide an antenna apparatus characterized by having a simple structure, in addition to the above described effects. 
     A twenty-third present invention corresponding to claim  23  can provide an antenna apparatus characterized by greater simplicity of performance adjustment in manufacture, in addition to the above described effects. 
     A twenty-fourth present invention corresponding to claim  24  can provide an antenna apparatus characterized by having stable operation, in addition to the above described effects. 
     A twenty-fifth present invention corresponding to claim  25  can provide a communication system characterized by having a simple structure. 
     A twenty-sixth present invention corresponding to claim  26  can provide a communication system characterized by having a simple structure.