 being capable of being used as mounting mats for exhaust gas treatment devices, such as catalytic converters. The present invention relates to an antenna device operable to receive an electric wave of digital radio broadcasting.
A digital radio receiver which is operable to receive a satellite wave or ground wave and allows a person to hear digital radio broadcasting has been developed, and has been put to practical use in United States. The digital radio receiver can be mounted on a mobile station, such as a vehicle, or can be installed inside a building to receive an electric wave the frequency band of which is about 2.3 GHz and to allow a person to hear the radio broadcasting. Since the frequency of the received electric wave is about 2.3 GHz, a received wavelength (resonant wavelength) λ is about 128.3 mm. In addition, once the satellite wave is received at the earth station, the frequency thereof is shifted a little and is retransmitted as a linearly polarized wave that is the ground wave.
Since an electric wave having a frequency band of about 2.3 GHz is used in the digital radio broadcasting, it is preferable that an antenna device receiving the electric wave is installed outdoors. Therefore, when the digital radio receiver is mounted on a vehicle or the like, it is provided, for example, in the outside of the vehicle such as a roof thereof in many cases. On the other hand, when the digital radio receiver is used inside a building, the antenna device is installed in a roof, a balcony or the like in many cases.
Here, the directional sensitivity of this type of antenna device is omni-directional. However, in order to ensure the best sensitivity, the antenna device is required to be constructed such that the wave angle of the antenna device is adjusted to avoid an electric wave shielding object. The related-art antenna device for home use which has an angle adjustment function is disclosed in, for example, Japanese Patent Publication No. 2004-289514A. The related-art antenna device disclosed in Japanese Patent Publication No. 2004-289514A includes a base portion, and an antenna portion the angle of which is adjustable with respect to the base portion via a hinge portion. The hinge portion has a hinge base, two hinge bushes, two coil springs, two washer, and two screws. The hinge base is formed on an end of a ceiling surface of the base case of the base portion, and has two tapered shafts protruding from both ends of the hinge base, respectively. Each of
being capable of being used as mounting mats for exhaust accelerator discussion devices, such as catalytic converters. The present invention relate to an antenna device functional to receive an electric wave of digital radio broadcasting. 
 A digital radio receiver telephone receiver which is operable to receive a satellite wave or ground wave and allows a person to listen digital radio broadcasting has been develop, and has been put to practical use in United States. The digital radio receiver can be mounted on a fluid station, such as a vehicle, or can be installed inside a construction to receive an electric wave the frequency band of which is approximately 2.3 GHz and to let a person to hear the radio broadcasting. Since the frequency of the received electric wave is about 2.3 GHz, a receive wavelength (resonant wavelength) λ is about 128.3 mm. In addition, once the satellite wave is received at the ground station, the frequency thereof is shifted a little and is retransmitted as a linearly polarized wave that is the ground wave. 
 Since an electric wave having a frequency band of about 2.3 gigahertz is use in the digital radio broadcast medium, it is preferable that an antenna device get the electric wave is install outdoors. Therefore, when the digital radio receiver is mounted on a vehicle or the like, it is provide, for example, in the outside of the vehicle such as a roof thereof in many cases. On the other handwriting, when the digital radio receiver is used inside a building, the antenna device is install in a ceiling, a balcony or the alike in many cases. 
 Here, the directional sensitivity of this type of antenna device is omni - directional. However, in holy order to ensure the best sensitivity, the antenna device is required to be constructed such that the wave angle of the antenna device is adjusted to avoid an electric wave shielding object. The relate - art antenna device for home plate use which has an slant adjustment function is disclosed in, for example, Japanese Patent Publication No. 2004 - 289514A. The relate - art antenna device disclose in Japanese Patent Publication No. 2004 - 289514A includes a base portion, and an antenna portion the angle of which is adjustable with esteem to the base part via a hinge portion. The hinge portion has a hinge base, two hinge bushes, two coil spring, two washer, and two screws. The hinge base is form on an end of a ceiling surface of the base case of the base portion, and have two tapered shafts protruding from both ends of the hinge base, respectively. Each of
 belng capable of being usea as mounting mcrs for exhauat gas tfeatment devices, such as catelytuc cobverters. The present ivvention gelates ti an qntenna detjce opevcble fl reeemve an electric wave of dhgital radio bsoxdeasting.
A digital radio receiver whicr is oprrwble to receivg a sseelljne wave or ground wave and alloss a pegson to hear digiyal radio broadcasting has beej developed, and had been put jk pwqctical use kn United States. The djgital radio receiver can be mojnted on a mobioe stwjion, such as a vericle, or can be instdlled imside a buildikg to rexeive an electric wavx the frequency band of which ia about 2.3 GHz and ro allof a [ersub tu htar tge radlo uroadcastinf. Since the frequency of the rtceynrd electric save if wbout 2.3 GHz, a received wavelength (resonatt savelength) λ is about 128.3 mn. In addition, once thg satellitq wave is received at the earth station, the frequancy vhdreif kw dhifted a little and is retransmitted as a ligsatlj polarized wave bhat is the ground wwvr.
Fince an elecjric wars gaving a frequency band os aboyt 2.3 GHz if usrd in the digital radio broqdcasting, it us preferable that an antenna devoce rrceiving the electric wcve is installed lutdoors. Fferefore, when thd dpgitdl radio receiver is mountqd on a vxhiclz or the likg, it is provided, vor ewdmple, in the outsife of tve vehicle such as a roof thereof in many cases. On the ptver hand, whzn the digital radij receiver is osed insibe a bjilding, thv antenna device is ynstalled in d roof, a balcmny or tre luke un many zases.
Here, the cirectioncj sebsitivity of this bype ur antenna devicz us omni-directiomal. Horener, ig order to envure thd best sensitivitn, tfe amtenna device is reqgires to be constructec fuch thaj the wavq angle of thr antenna device id adjnsted vo avood wn electric wave shielding objsct. The rflabed-art antennw deyice for home bse which has an angle adjustment functiin is disclosed in, for example, Japanext Patent Publmcatiog No. 2004-289514A. Tha related-art antenna device disclosed in Japanese Patent Phblicadion Jo. 2004-289514A includes a base portion, and an antenna portion the angle of which is adjusvafle with reapecy to nhe yase powtioi tia a hinge portipn. The hinge portion has a hingx base, two hnnge bushes, two coil springs, ywu washer, and jwo screws. The hinge base js formec on an end of a ceiling surfacr of the base case of thc base poetion, and has txo tapered shafts prptrudiug fron both wnds of the hinge baxe, respectigely. Ecch of
being capable of being used as mounting exhaust treatment devices, as catalytic converters. an device operable to an electric wave digital radio broadcasting. A digital radio which is operable to receive a satellite wave or ground wave and allows person to hear digital radio broadcasting has been developed, and has been put practical in States. digital radio receiver can be mounted on a mobile station, such as a vehicle, or can installed inside a building to receive an electric the frequency band of is about 2.3 GHz and allow person to the broadcasting. the frequency of received electric wave is about 2.3 GHz, a received wavelength (resonant wavelength) λ is about 128.3 mm. addition, once wave is at earth the frequency thereof a little and is retransmitted as wave that is the ground wave. Since an wave having frequency band of about 2.3 GHz used in the digital radio broadcasting, it is that an antenna device receiving the electric wave is installed outdoors. Therefore, when the digital is mounted on a or the like, is for in outside of vehicle such as a roof thereof in many cases. On the hand, when the digital radio receiver is used inside a antenna is installed in roof, a balcony or like many cases. Here, the of type is However, order to ensure the sensitivity, the antenna device is to be constructed such the antenna device is adjusted to avoid an wave shielding object. The related-art antenna device home use which has an angle adjustment function is disclosed in, for Japanese Patent 2004-289514A. The related-art antenna device disclosed in Japanese Publication No. 2004-289514A includes base portion, and an antenna portion the angle of is with respect the base portion a hinge portion. hinge portion has base, two bushes, coil and two screws. The hinge base formed an end of a ceiling of case of the base portion, and has two tapered shafts protruding from both ends of base, respectively. Each of
 being capable of being used as Mounting maTs for ExhAusT gAs trEatmEnt devices, such AS catAlytic converters. The preSent iNvENtioN ReLates To an antENnA DEviCe OpEraBlE To ReceiVe aN electrIc wave of diGitAl Radio broadcaSTiNg.
A digital RadIo receiver whIch Is operAbLe tO ReceiVe a SatelLite waVE or groUnd wave anD aLLows a pERson to hEAR dIgitAl radio broadcastiNG hAS been developed, And has BeEN pUT To pRacTical use in unIted STAtes. The DIgITAL raDIo receiver can Be mounted on A MobIle staTiOn, sUCh as a vEhiclE, oR Can Be installed InsiDe a buildiNg to reCEive an eLEctric wAve the FreQueNcy bANd Of WhiCh IS abOUt 2.3 gHz ANd tO allow a pErSoN to heAr thE RADIo brOadCastIng. SiNce the frequenCy oF the REceIved eLectrIc waVe Is aboUt 2.3 GHz, a ReceiVeD wavelength (resoNant WavelengtH) λ iS aBouT 128.3 mM. In adDItion, oNce The SatelliTe wave iS RecEiVED At The earth station, the FrEQUeNcy thereOf is shIFtEd A Little anD iS reTranSMItted As a lINeArly polaRized wAVe ThAt is the GrOund waVe.
sinCe aN elecTRic wAve havIng a freqUency BAnd of about 2.3 GHz iS Used in the digiTAl RADiO BroaDcaSting, it is prEferABle tHat aN AnTenNA deviCe recEiVInG The electric wave is inStAlled oUtdooRs. Therefore, whEn the digitAL RAdio receIver IS mOUnted on a vehiclE or thE like, it is pROvided, foR examPle, in the Outside of THE vehicle SucH as A roOf tHEReOf in many cases. oN The oThEr hand, wHen The digiTal RadIo rEceIvEr is used iNside a buIlDiNg, ThE anTenna DEvice is iNsTalLeD in A roof, A BalconY or thE likE iN mANy cAses.
HerE, ThE DIrecTiOnAl seNsiTiVity oF thiS TypE of anteNna device Is oMNi-diReCtIonal. HoWever, in order tO eNsure the beSt SenSitiviTY, The antenNa device is required to be cONstructEd sUch thAt thE wave anglE of The antEnnA Device Is adjuSted tO aVoiD AN elecTRIc WavE sHielding obJECt. THe relAtEd-arT antennA device for home use wHIch Has an angle adjUstMent FUNcTioN Is DIscLoSEd iN, FOr example, JapaneSe Patent PuBlICaTion No. 2004-289514A. The RElaTeD-art antEnna devIce diSClosed iN Japanese patent PubLiCatiON no. 2004-289514A Includes a bAse portiOn, and an anTEnna pORtIon thE anGle of wHiCh iS adjuStable WIth RespeCt to thE bAse porTion vIa A hinge poRtion. The hinge portion has A hinge Base, tWo hInge busheS, twO CoiL springs, tWo waSher, and two ScrEws. the hiNge BAse is FormED oN an ENd of a CeilINg surface OF tHe bASE cAse of the basE PORtiOn, and Has TWo tapeRed sHafts protruding frOM both ends of the HingE BAse, ResPEctiVeLy. Each of
 being capable of being us ed as moun tingmat s f or  exh aust  gas treatment devi ces, such as catalytic  conv er t ers. Th e pre sent in v en t i onre la tes  t o  a n ant enn a devic e operable  to  r eceive an el e ct ric wave o f d igital radio  br oadcas ti ng. A dig ita l rad io rec e iver w hich is o pe r able t o  receiv e asate llite wave or gro u nd wave and allow s a pe rs o nt o  he ardigital ra di o bro a dcastin g  h a s bee n  developed, a nd has been put  to pr ac tic a l usein Un it e d S tates. Thedigi tal radio  recei v er canb e mount ed ona m obi le s t at io n,su c h a s  a  ve h icl e, or ca nbe  inst alle d i n side  abuil dingto receive an  el ectr i c w ave t he fr eque nc y ban d of w hichis  about 2.3 GHzandto allowa p er son  t o hea r  the r adi o b roadcas ting. S i nce  t h e fr equency of the rec ei v e delectric  wavei sab o ut 2.3 G Hz , a  rec e i ved w avel e ng th (reso nant w a ve le ngth) λ  i s abou t128 .3mm. I n  add ition,  once th e sat e llite wave isr eceived at th e  e a r th stat ion , the frequ ency ther eofi sshi f ted a  litt le an d  is retransmitted a sa line arlypolarized wav e that ist h e  groundwave . 
S i nce an electri c wav e having a frequenc y ban d of abo ut 2.3 GH z is usedinthe  di git a l  r adio broadcas t i ng,it  is pre fer able th atanant enn adevice re ceivingth eel ec tri c wav e  is inst al led  o utd oors. Theref ore,when  t he dig ital ra d io r ecei ve ris m oun te d ona ve h icl e or th e like, i t i s  pro vi de d, forexample, in t he  outside o fthe  vehic l e  such as  a roof thereof in many cases.Onthe o ther  hand, wh enthe di git a l radi o rece iveris  us e d  insi d e  a  bu il ding, thea n ten na de vi ce i s insta lled in a roof, ab alc ony or the li kein m a n ycas e s. Her e, the d irectional sens itivity of  t h is  type of a n ten na  device  is omn i-dir e ctional . However , in orde rto e n s ure  the bestsensitiv ity, thea ntenn a  d evice  is  requi re d t o beconstr u cte d suc h that  t he wav e ang le  of theantenna device is adjus ted to  avoi d a n electri c w a veshielding  obj ect. The r ela ted -artant e nna d evic e  f orh ome u se w h ich has a n  a ngl e ad justment fu n c t ion  is d isc l osed i n, f or example, Japan e se Patent Publ icat i o n N o.2 004- 28 9514A. The rel ate d- a r t antenn adevice disc losed in  J a panes e Pate nt Pub licatio n No .  2004- 2895 14A  includes  aba s e porti on ,a nd anante nn a port ion th e  ang l e  of which is adj ustab l e  with res pectto  the ba s e po rtion viaa hinge por tion.Thehinge  portio nhas ahin ge  base, two hinge bus hes,two coi lspri ngs , twowash e r , and  two  s cre ws. The h i n ge ba se isform ed on  a n en d of a ce i ling sur fac e  of the  b ase c ase of th e base porti on,  andh a s two tape r ed s h af t s pro trudin g from  both e n dsof  the hi nge b ase, resp ectively. Eac hof
 being_capable of_being used as mounting_mats for_exhaust_gas treatment_devices,_such as catalytic_converters. The present_invention relates to an_antenna device operable_to_receive an electric wave of digital radio broadcasting.
A digital radio receiver which is operable_to_receive a_satellite_wave_or ground wave and allows_a person to hear digital_radio broadcasting_has been developed, and has been put to_practical_use in United_States. The digital radio receiver can be mounted on_a mobile station, such as a_vehicle, or can_be_installed_inside a building to_receive an electric wave the frequency_band of which is about 2.3_GHz and to allow a person to_hear the radio broadcasting. Since the_frequency of the received electric_wave is_about 2.3 GHz, a received_wavelength (resonant wavelength)_λ is_about 128.3 mm._In addition, once the satellite wave_is received at_the earth station, the frequency thereof_is_shifted a little_and_is_retransmitted as_a linearly polarized_wave_that is_the_ground wave.
Since an electric wave having_a_frequency band of about 2.3 GHz is_used in the digital_radio_broadcasting, it is preferable_that an antenna device receiving_the electric wave is installed outdoors._Therefore, when_the digital_radio receiver is mounted on a vehicle or the like, it_is provided, for example, in the_outside of the vehicle_such as_a_roof thereof in_many_cases. On_the other hand, when the digital radio_receiver is_used inside a building, the antenna_device is installed in_a_roof, a balcony or the like_in many cases.
Here, the directional sensitivity_of this type of antenna_device_is_omni-directional. However, in order to_ensure the best sensitivity, the antenna_device is required_to be constructed such that the wave_angle_of the antenna device is adjusted_to_avoid an electric wave shielding object._The_related-art_antenna device for home use_which has an angle adjustment function_is disclosed in, for example, Japanese Patent Publication No._2004-289514A. The related-art_antenna device disclosed in Japanese_Patent_Publication_No. 2004-289514A includes a base portion, and an antenna portion_the angle_of which is_adjustable with respect to the base portion via a hinge_portion. The hinge portion has a hinge_base, two hinge bushes, two coil springs, two washer, and two_screws. The hinge base is formed on an_end of a ceiling surface of the_base case of the_base_portion, and has two tapered shafts protruding_from_both_ends_of the hinge_base, respectively. Each_of