JP3798386B2

JP3798386B2 - Radio axis adjustment device

Info

Publication number: JP3798386B2
Application number: JP2003124001A
Authority: JP
Inventors: 才中川
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2003-04-28
Filing date: 2003-04-28
Publication date: 2006-07-19
Anticipated expiration: 2023-04-28
Also published as: JP2004325400A

Description

【０００１】
【発明の属する技術分野】
この発明は、送信した電波の測定対象で反射した電波を受信することによって測定対象を検出し、測定対象までの距離、相対速度、角度を算出する車載用レーダ装置の電波軸調整装置に関する。
【０００２】
【従来の技術】
従来の車載用レーダ装置では、それに備えられている送受信手段の放射パターンにおいて電界強度の最も強い方向（以下、電波軸と称す。）と車両の進行していく方向（以下、目標軸と称す。）とがずれて固定されていると、検出された測定対象の角度に誤差が生じ、隣接車線を走行している車両を先行車と判断したり、先行車を先行車ではないと誤った判断をする可能性がある。
そこで、電波軸と目標軸とを一致させるために、目標軸上に被検出物を設置し、この被検出物による反射電波の受信電界強度を測定し、この受信電界強度が最大にするように電波軸を調整する方法がある（例えば、特許文献１参照。）。
【０００３】
【特許文献１】
特開平７−８１４９０号公報
【０００４】
【発明が解決しようとする課題】
しかし、車載用レーダ装置に使用される送受信手段として一般的なアンテナ(指向性を有するアンテナ)の放射パターンでは、電波軸の近傍、つまり電界強度最大点付近における、角度の変化に対する受信電界強度の変化が僅かである。そのため、電界強度が最大になったか否かの判断が難しく、電波軸を精度良く調整することは困難である。
【０００５】
この発明の目的は、電波軸を精度良く目標軸に調整する車載用レーダ装置の電波軸調整装置を提供することである。
【０００６】
【課題を解決するための手段】
この発明に係わる電波軸調整装置は、電波軸および上記電波軸とナル角度をなすナル軸を有し、電波を送受信する送受信手段と、上記送受信手段を上記送受信手段の中心点を中心に電波基準面内に回転させる軸調整機構と、上記送受信手段の放射パターンの電波軸が車両の目標軸上にあるときの放射パターンの左右のナル軸上に配設された電波反射手段と、上記送受信手段から送信された電波の上記電波反射手段での反射波の電界強度を計測する電界強度計測手段と、上記電界強度に基づいて、上記送受信手段の電波軸を上記目標軸に一致させるように上記軸調整機構を制御し上記送受信手段を回転させる電波軸調整手段とを有する。
【０００７】
【発明の実施の形態】
実施の形態１．
図１は、この発明の実施の形態１の電波軸調整装置のブロック図である。図２は、送受信アンテナの電波軸を調整する手順のフローチャートである。図３は、図２のフローチャートを説明するための放射パターンと電波反射手段の位置関係図である。図４は、図１の送受信手段の指向性パターン図である。
【０００８】
この説明において、電波軸調整装置は、車両に搭載された車載レーダ装置の送受信手段の電波軸を調整する場合について説明する。車両の４輪を平らな地面に接地し、そのとき得られる車両の前輪の車軸を含み、地面に平行な平面を基準面とする。目標軸は、この基準面上にあり、前輪の車軸に垂直である。送受信手段である送受信アンテナの中心点は、基準面から所定の高さだけ離れ、基準面と平行な平面（以下、電波基準面と称す。）に含まれる。送受信アンテナから送信される電波の放射パターンは、この電波基準面上において極座標系で表現される。なお、説明を簡単にするため、基準面と電波基準面とは平行であるとして説明するが、平行でないときは２軸に渡って電波軸を調整することによって、電波軸を目標軸に合わせることができる。また、電波軸の回転方向は車両を上方から見下ろしたときの方向である。
【０００９】
電波軸調整装置は、電波を送受信する送受信手段１と、送受信手段１を支持し、電波基準面内で送受信手段１の中心点を中心として回転自在に車両２によって支持された軸調整機構３と、送受信手段１の中心点から所定の距離ＲＬだけ離間し、車両２によって支持された電波反射手段４Ｌと、これらを制御する制御手段５とを備えている。
【００１０】
制御手段５は、送受信手段１に向けて送信信号を送出する発振手段６と、送受信手段１で受信された電波の電界強度を検出する電界強度計測手段７と、電界強度に基づいて軸調整機構３の回転角を算出して軸調整機構３へ指示する電波軸調整手段８とを備えている。
【００１１】
送受信手段１は、通常送受信アンテナなどからなっている。送受信手段１は、車両２の前グリルの近傍に、軸調整機構３により支持されている。
【００１２】
軸調整機構３は、送受信手段１の中心点を中心に送受信手段１の電波軸の角度を電波基準面内で調整できるように、アクチュエータを備えている。アクチュエータは、モータなどからなっている。
【００１３】
電波反射手段４Ｌは、コーナーリフレクタなどからなっている。電波反射手段４Ｌは、車両２に一端を支持され、長さＲＬのアーム９Ｌによって支持されている。車両２に取り付ける前に電波暗室内で送受信手段１の指向性を示す放射パターンを計測し、その放射パターンから、送受信手段１の電波軸１１およびナル点を求める。図４に計測された放射パターンの一例を示す。送受信手段１の電波軸１１は、送受信手段１の中心点を通過し、電界強度が最大である方向を示す軸である。さらに、ナル点（ＮＵＬＬ）は、放射パターンにおけるメインローブとメインローブに隣接したサイドローブとの間の電界強度が雑音レベルに近い状態を示す方向である。ナル点は、図４に示すように電波軸１１からナル角度（θＬ）だけ反時計方向および時計方向に回転した方向である。送受信手段１のナル軸１２Ｌは、電波軸１１からナル角度（θＬ）だけ車両の進行方向に向かって反時計方向に回転した軸である。
【００１４】
電波反射手段４Ｌで反射された反射波の電界強度がナル点の近傍の値以下になったかどうかを判断するために、ノイズレベルに対して余裕を考慮してスレショルド値ＴＨＬをあらかじめ設定している。
【００１５】
ナル軸１２Ｌ上にある電波反射手段４Ｌは、１辺１１０ｍｍの三角錐コーナレフレクタからなっている。電波反射手段４Ｌは、アーム９Ｌの先端部に電波反射手段４Ｌの反射軸が送受信手段１の中心点に概略向くように固定される。
【００１６】
発振手段６は、７６．５ＧＨｚ帯のミリ波を送信する発振器からなっている。電界強度計測手段７は、受信した７６．５ＧＨｚ帯のミリ波から電界成分を抽出し、その強度を計測する電界強度計測器からなっている。電波軸調整手段８は、後述した手順に基づき電界強度の変化とあらかじめ設定したスレショルド値ＴＨＬとを用いて、軸調整機構３の回転方向および回転角度の値を出力する。電波軸調整手段８は、コンピュータによって構成され、電界強度、角度などの値は記憶手段（特に図示せず。）に記憶されている。
また、制御手段５は、受信電界強度ＬＭを表示する表示手段１０を備えている。なお、このときの表示形式としては、数字によるディジタル表示又は指針の振れによるアナログ表示の何れでも良い。
【００１７】
次に、図２を参照して送受信手段１の電波軸１１を調整する手順について説明する。この説明において、図３に示すように送受信手段１の電波軸１１は、電波基準面上で目標軸１３に対して車両進行方向に向かって反時計方向にθだけ回転している。
ステップ（以下、Ｓと略す。）１０で、発振手段６は所定の信号を励起し、送受信手段１から電波を車両２の進行方向へ送信する。Ｓ１１で、電波反射手段４Ｌにて反射された反射電波を送受信手段１は受信し、電界強度計測手段７へ受信信号を伝送する。Ｓ１２で、電界強度計測手段７は、受信信号の電界強度ＬＭを計測する。Ｓ１３で、電波軸調整手段８は、電界強度ＬＭを受信電界強度ＬＭ１として記憶する。Ｓ１４で、電波軸調整手段８は、軸調整機構３を制御し、角度０．１°だけ反時計方向へ送受信手段１を回転する。Ｓ１５で、発振手段６は所定の信号を励起し、送受信手段１から電波を車両２の進行方向へ送信する。Ｓ１６で、電波反射手段４Ｌにて反射された反射電波を送受信手段１は受信し、電界強度計測手段７へ受信信号を伝送する。Ｓ１７で、電界強度計測手段７は、受信信号の電界強度ＬＭを計測する。Ｓ１８で、電波軸調整手段８は、電界強度ＬＭを受信電界強度ＬＭ２として記憶する。Ｓ１９で、記憶された受信電界強度ＬＭ１とＬＭ２とを比較し、ＬＭ１＞ＬＭ２であれば、電波軸の回転がまだ足りないことを意味するので、Ｓ２０へ進み、ＬＭ１＜ＬＭ２であれば、電波軸の回転方向が逆であることを意味するので、Ｓ２５に進む。Ｓ２０で、電波軸調整手段８は、軸調整機構３を制御し、角度０．１°だけ反時計方向へ送受信手段１を回転する。Ｓ２１で、発振手段６は所定の信号を励起し、送受信手段１から電波を車両２の進行方向へ送信する。Ｓ２２で、電波反射手段４Ｌにて反射された反射電波を送受信手段１は受信し、電界強度計測手段７へ受信信号を伝送する。Ｓ２３で、電界強度計測手段７は、受信信号の電界強度ＬＭを計測する。Ｓ２４で、計測した電界強度ＬＭとあらかじめ設定したスレショルドＴＨＬ（例えば、電界強度ゼロである。）と比較し、ＬＭ＞ＴＨＬであれば、Ｓ２０へ戻り、ＬＭ≦ＴＨＬであれば、送受信手段の電波軸と目標軸が一致したと判断し、軸調整手順は完了する。Ｓ２５で、電波軸調整手段８は、軸調整機構３を制御し、角度０．１°だけ時計方向へ送受信手段１を回転する。Ｓ２６で、発振手段６は所定の信号を励起し、送受信手段１から電波を車両２の進行方向へ送信する。Ｓ２７で、電波反射手段４Ｌにて反射された反射電波を送受信手段１は受信し、電界強度計測手段７へ受信信号を伝送する。Ｓ２８で、電界強度計測手段７は、受信信号の電界強度ＬＭを計測する。Ｓ２９で、計測した電界強度ＬＭとあらかじめ設定したスレショルドＴＨＬ（例えば、電界強度ゼロである。）と比較し、ＬＭ＞ＴＨＬであれば、Ｓ２５へ戻り、ＬＭ≦ＴＨであれば、送受信手段の電波軸と目標軸が一致したと判断し、軸調整手順は完了する。
【００１８】
このような電波軸調整装置は、電波軸の回転角度に対する電波反射手段からの反射波の電界強度の変化が大きいので、高い精度で容易に送受信手段の電波軸と目標軸とを一致させることができる。
【００１９】
さらに、スレショルド値をあらかじめ設定してあるので、電波軸１１と目標軸１３とが一致したことを容易に判断できる。
【００２０】
さらに、スレショルド値をゼロと設定されているので、確実に放射パターンのナル点が電波反射手段に対向していることが分かる。
【００２１】
なお、送受信手段の電波軸が、目標軸に対して時計方向にずれていたとしても、実施の形態１と同じ方法で送受信手段の電波軸１１と目標軸１３とを一致させることができる。
【００２２】
さらに、目標軸上に被検出物である電波反射手段４Ｌを配置しないため、製造中の車両をそのまま発進させることが出来、製造ラインのラインタクトを悪化させない。
【００２３】
さらに、電波反射手段４Ｌとして、通常散乱断面積１０ｍ^２程度の標準ターゲットが必要であるが、製造ラインでは大きな構造物を配置できないので、電波反射手段４Ｌをコーナーリフレクタとすると構造物を小型化できる。
【００２４】
実施の形態２．
図５は、この発明の実施の形態２の電波軸調整装置の構成図である。図６は、図５の軸調整手順を示すフローチャートである。図７は、放射パターンと目標軸との関係図である。図８は、放射パターンである。図５の電波軸調整装置と図１の電波軸調整装置との異なる点は、電波反射手段が１個からさらに１個追加して２個になった点であり、その他は同様である。なお、アームは省略してある。同様な部分の説明は省略する。電波反射手段４Ｒは、送受信手段１の中心点から距離ＲＲだけ離れた位置にアームで支持されている。さらに、電波反射手段４Ｒは、目標軸１３からＮＵＬＬ角度（θＲ）だけ車両進行方向に向かって時計方向に回転したナル軸１２Ｒ上に配設されている。
また、実施の形態２では、電波反射手段４Ｌ、４Ｒの一方を電波吸収体で覆い、電波の反射を減少している。この電波吸収体は、磁性金属微粉末とゴムとを一体化した電波吸収膜と、その電波吸収膜の裏面に接着された金属箔とからなっている。
また、スレショルドＴＨＲは、ＴＨＬと同様にノイズレベルに余裕分を加えた値としている。
【００２５】
次に、この実施の形態２における送受信手段１の電波軸１１を調整する手順について図６を参照して説明する。この説明において、送受信手段１の電波軸１１は、図７に示すように電波基準面上で目標軸に対して車両進行方向に向かって反時計方向にθだけ回転している。
Ｓ１１０で、右電波反射手段４Ｒを電波吸収体で覆う。Ｓ１１１で、発振手段６は所定の信号を励起し、送受信手段１から電波を車両２の進行方向へ送信する。Ｓ１１２で、左電波反射手段４Ｌにて反射された反射電波を送受信手段１は受信し、電界強度計測手段７へ受信信号を伝送する。Ｓ１１３で、電界強度計測手段７は、受信信号の電界強度ＬＭを計測する。Ｓ１１４で、電波軸調整手段８は、電界強度ＬＭを受信電界強度ＬＭ１として記憶する。Ｓ１１５で、左電波反射手段４Ｌを電波吸収体で覆う。Ｓ１１６で、発振手段６は所定の信号を励起し、送受信手段１から電波を車両２の進行方向へ送信する。Ｓ１１７で、右電波反射手段４Ｒにて反射された反射電波を送受信手段１は受信し、電界強度計測手段７へ受信信号を伝送する。Ｓ１１８で、電界強度計測手段７は、受信信号の電界強度ＲＭを計測する。Ｓ１１９で、電波軸調整手段８は、電界強度ＲＭを受信電界強度ＲＭ１として記憶する。Ｓ１２０で、電波軸調整手段８は、軸調整機構３を制御し、角度０．１°だけ反時計方向へ送受信手段１を回転する。Ｓ１２１で、右電波反射手段４Ｒを電波吸収体で覆う。Ｓ１２２で、発振手段６は所定の信号を励起し、送受信手段１から電波を車両２の進行方向へ送信する。Ｓ１２３で、左電波反射手段４Ｌにて反射された反射電波を送受信手段１は受信し、電界強度計測手段７へ受信信号を伝送する。Ｓ１２４で、電界強度計測手段７は、受信信号の電界強度ＬＭを計測する。Ｓ１２５で、電波軸調整手段８は、電界強度ＬＭを受信電界強度ＬＭ２として記憶する。Ｓ１２６で、左電波反射手段４Ｌを電波吸収体で覆う。Ｓ１２７で、発振手段６は所定の信号を励起し、送受信手段１から電波を車両２の進行方向へ送信する。Ｓ１２８で、右電波反射手段４Ｒにて反射された反射電波を送受信手段１は受信し、電界強度計測手段７へ受信信号を伝送する。Ｓ１２９で、電界強度計測手段７は、受信信号の電界強度ＲＭを計測する。Ｓ１３０で、電波軸調整手段８は、電界強度ＲＭを受信電界強度ＲＭ２として記憶する。Ｓ１３１で、記憶された受信電界強度ＬＭ１とＬＭ２とを比較し、さらにＲＭ１とＲＭ２とを比較する。ＬＭ１＞ＬＭ２かつＲＭ１＞ＲＭ２であれば、電波軸の回転がまだ足りないことを意味するので、Ｓ１３２へ進み、ＬＭ１＜ＬＭ２かつＲＭ１＜ＲＭ２であれば、電波軸の回転方向が逆であることを意味するので、Ｓ１４３に進む。Ｓ１３２で、電波軸調整手段８は、軸調整機構３を制御し、角度０．１°だけ反時計方向へ送受信手段１を回転する。Ｓ１３３で、右電波反射手段４Ｒを電波吸収体で覆う。Ｓ１３４で、発振手段６は所定の信号を励起し、送受信手段１から電波を車両２の進行方向へ送信する。Ｓ１３５で、左電波反射手段４Ｌにて反射された反射電波を送受信手段１は受信し、電界強度計測手段７へ受信信号を伝送する。Ｓ１３６で、電界強度計測手段７は、受信信号の電界強度ＬＭを計測する。Ｓ１３７で、左電波反射手段４Ｌを電波吸収体で覆う。Ｓ１３８で、発振手段６は所定の信号を励起し、送受信手段１から電波を車両２の進行方向へ送信する。Ｓ１３９で、右電波反射手段４Ｒにて反射された反射電波を送受信手段１は受信し、電界強度計測手段７へ受信信号を伝送する。Ｓ１４０で、電界強度計測手段７は、受信信号の電界強度ＲＭを計測する。Ｓ１４１で、計測した電界強度ＬＭ、ＲＭとあらかじめ設定したスレショルドＴＨＬ、ＴＨＲとをそれぞれ比較する。ＬＭ＞ＴＨＬかつＲＭ＞ＴＨＲであれば、Ｓ１３２へ戻り、ＬＭ≦ＴＨＬかつＲＭ≦ＴＨＲであれば、送受信手段１の電波軸と目標軸が一致したと判断し、軸調整手順は完了する。Ｓ１４２で、電波軸調整手段８は、軸調整機構３を制御し、角度０．１°だけ時計方向へ送受信手段１を回転する。Ｓ１４３で、右電波反射手段４Ｒを電波吸収体で覆う。Ｓ１４４で、発振手段６は所定の信号を励起し、送受信手段１から電波を車両２の進行方向へ送信する。Ｓ１４５で、左電波反射手段４Ｌにて反射された反射電波を送受信手段１は受信し、電界強度計測手段７へ受信信号を伝送する。Ｓ１４６で、電界強度計測手段７は、受信信号の電界強度ＬＭを計測する。Ｓ１４７で、左電波反射手段４Ｌを電波吸収体で覆う。Ｓ１４８で、発振手段６は所定の信号を励起し、送受信手段１から電波を車両２の進行方向へ送信する。Ｓ１４９で、右電波反射手段４Ｒにて反射された反射電波を送受信手段１は受信し、電界強度計測手段７へ受信信号を伝送する。Ｓ１５０で、電界強度計測手段７は、受信信号の電界強度ＲＭを計測する。Ｓ１５１で、計測した電界強度ＬＭ、ＲＭとあらかじめ設定したスレショルドＴＨＬ、ＴＨＲとをそれぞれ比較する。ＬＭ＞ＴＨＬかつＲＭ＞ＴＨＲであれば、Ｓ１３２へ戻り、ＬＭ≦ＴＨＬかつＲＭ≦ＴＨＲであれば、送受信手段１の電波軸と目標軸が一致したと判断し、軸調整手順は完了する。
【００２６】
なお、他の電波反射体から電界強度を受信しないように、電波吸収体で電波反射手段を隠したが、電波反射手段を取り換えて計測してもよい。
【００２７】
なお、放射パターンの電波軸１１が、目標軸１３に対して右にずれていたとしても、同じ方法でレーダ装置の電波軸１１と目標軸１３を一致させることができる。
【００２８】
この電波軸調整装置は、左右のナル軸上に電波反射手段を備えてあるので、一方の電波反射手段だけのときは変化が少ないときでも、両方の反射波のうちどちらかでは変化が見られるので実施の形態１より高い精度でレーダ装置の電波軸１１と目標軸１３を一致させることができる。
【００２９】
さらに、左右の電界強度にそれぞれスレショルド値を設定してあるので、左右のバランス良く調整することができる。
【００３０】
実施の形態３．
図９は、この発明の実施の形態３の電波軸調整装置の軸調整手順のフローチャートである。なお、Ｓ１５１までは図６と同様であり、Ｓ１８１とＳ１８２だけが異なっているので同様な部分の説明は省略する。Ｓ１４２で、電界強度ＬＭおよびＲＭがそれぞれスレショルドＴＨＬとＴＨＲに比較して小さくなったとき、Ｓ１８１でさらに、ＬＭとＲＭの差分の絶対値を求め、その値があらかじめ設定した閾値ΔＢと比較し、絶対値が閾値より小さいとき軸調整が完了したと判断する。閾値より絶対値が大きいときはさらにＳ１３２に戻って軸を回転する。Ｓ１８２もＳ１８１と同様の操作が行われ、ＬＭとＲＭの差分の絶対値が閾値ΔＢより大きいときはＳ１４２に戻って軸調整を継続する。
【００３１】
このような電波軸調整装置は、左右の反射波の電界強度の差分をも小さくする調整をおこなうので、実施の形態２よりもさらに左右のバランス良くレーダ装置の電波軸１１と目標軸１３とを一致させることができる。
【００３２】
実施の形態４．
図１０は、この発明の実施の形態４の電波軸調整装置の構成図である。図１１、図１２は、図１０の軸調整手順を示すフローチャートである。図１３は、この実施の形態４の説明のための放射パターンと目標軸との関係図である。図１４は、放射パターンである。図１０の電波軸調整装置と図５の電波軸調整装置との異なる点は、電波反射手段が２個からさらに１個追加して３個になった点であり、その他は同様である。同様な部分の説明は省略する。また図１２のフローチャートのＳ２３１からＳ２４０は図６のＳ１３２からＳ１４１と、Ｓ２４１からＳ２５０はＳ１４２からＳ１５１と同様であるので説明は省略する。電波反射手段４Ｃは、送受信手段１の中心点から距離ＲＣだけ離れた位置にアームで支持されている。さらに、電波反射手段４Ｃは、目標軸１３上に支持されている。
なお、第一のスレショルド値として、目標軸上に配設した電波反射手段４Ｃで反射された反射波の電界強度ＣＭに対応した値ＴＨＣとし、ＴＨＣはあらかじめ計測した放射パターンの電波軸上の電界強度から求めた値とする。このＴＨＣはおおよそ目標軸の近傍に電波軸が近づいたことを判断するために設定されている。さらに、第二のスレショルド値として、実施の形態２のスレショルド値ＴＨＬおよびＴＨＲをゼロに設定してある。
【００３３】
以下、図１１、図１２を参照してこの実施の形態４の軸調整手順を説明する。この説明において、送受信手段１の電波軸１１は、図１３に示すように電波基準面上で目標軸に対して車両進行方向に向かって反時計方向にθだけ回転している。
【００３４】
Ｓ２１０で、左右電波反射手段４Ｌ、４Ｒを電波吸収体で覆う。Ｓ２１１で、発振手段６は所定の信号を励起し、送受信手段１から電波を車両２の進行方向へ送信する。Ｓ２１２で、中央電波反射手段４Ｃにて反射された反射電波を送受信手段１は受信し、電界強度計測手段７へ受信信号を伝送する。Ｓ２１３で、電界強度計測手段７は、受信信号の電界強度ＣＭを計測する。Ｓ２１４で、電波軸調整手段８は、電界強度ＣＭを受信電界強度ＣＭ１として記憶する。Ｓ２１５で、電波軸調整手段８は、軸調整機構３を制御し、角度０．１°だけ反時計方向へ送受信手段１を回転する。Ｓ２１６で、発振手段６は所定の信号を励起し、送受信手段１から電波を車両２の進行方向へ送信する。Ｓ２１７で、中央電波反射手段４Ｃにて反射された反射電波を送受信手段１は受信し、電界強度計測手段７へ受信信号を伝送する。Ｓ２１８で、電界強度計測手段７は、受信信号の電界強度ＣＭを計測する。Ｓ２１９で、電波軸調整手段８は、電界強度ＣＭを受信電界強度ＣＭ２として記憶する。Ｓ２２０で、記憶された受信電界強度ＣＭ１とＣＭ２とを比較する。ＣＭ１＜ＣＭ２であれば、電波軸の回転がまだ足りないことを意味するので、Ｓ２２１へ進み、ＣＭ１＞ＣＭ２であれば、電波軸の回転方向が逆であることを意味するので、Ｓ２２６に進む。Ｓ２２１で、電波軸調整手段８は、軸調整機構３を制御し、角度０．１°だけ反時計方向へ送受信手段１を回転する。Ｓ２２２で、発振手段６は所定の信号を励起し、送受信手段１から電波を車両２の進行方向へ送信する。Ｓ２２３で、中央電波反射手段４Ｃにて反射された反射電波を送受信手段１は受信し、電界強度計測手段７へ受信信号を伝送する。Ｓ２２４で、電界強度計測手段７は、受信信号の電界強度ＣＭを計測する。Ｓ２２５で、計測した電界強度ＣＭとあらかじめ設定したスレショルドＴＨＣと比較し、ＣＭ＜ＴＨＣであれば、Ｓ２２１へ戻り、ＣＭ≧ＴＨＣであれば、送受信手段１の電波軸が目標軸と大まかに一致したと判断し、Ｓ２３１へ進む。Ｓ２２６で、電波軸調整手段８は、軸調整機構３を制御し、角度０．１°だけ時計方向へ送受信手段１を回転する。Ｓ２２７で、発振手段６は所定の信号を励起し、送受信手段１から電波を車両２の進行方向へ送信する。Ｓ２２８で、中央電波反射手段４Ｃにて反射された反射電波を送受信手段１は受信し、電界強度計測手段７へ受信信号を伝送する。Ｓ２２９で、電界強度計測手段７は、受信信号の電界強度ＣＭを計測する。Ｓ２３０で、計測した電界強度ＣＭとあらかじめ設定したスレショルドＴＨＣと比較し、ＣＭ＜ＴＨＣであれば、Ｓ２２６へ戻り、ＣＭ≧ＴＨＣであれば、送受信手段１の電波軸と目標軸が大まかに一致したと判断し、Ｓ２４１へ進む。Ｓ２３１からＳ２４０とＳ２４１からＳ２５０とは中央電波反射手段４Ｃを電波吸収体で覆い、左右の電波吸収手段４Ｌ、４Ｒを用いてさらに微細に軸調整を進める。
【００３５】
なお、放射パターンＡＰの電波軸１１が、目標軸１３に対して右にずれていたとしても、上記実施例と同じ方法でレーダ装置の電波軸１１と目標軸１３を一致させることができる。
【００３６】
この電波軸調整装置は、中央電波反射手段４Ｃを目標軸１３上に追加配置し、受信電界強度ＣＭがスレッショルドＴＨＣ以上になるように電波軸１１を回転するので、電波軸１１が大きくずれている場合でも、電波軸１１と目標軸１３を一致させることができる。
【００３７】
さらに、目標軸１３上の電波反射手段４Ｃから反射された反射波の電界強度に対してスレショルド値が設定されているので、ナル軸の近傍に近づいたことを判断することができ、すみやかに左右の電波反射手段４Ｌ、４Ｒを用いた調整に移行することができる。
【００３８】
さらに、スレショルド値として、あらかじめ計測された放射パターンの電波軸上の電界強度から求めているので、電波軸が目標軸に大まかに近づいたことが分かる。
【００３９】
また、左右の電波反射手段４Ｌ、４Ｒから反射された反射波の電界強度がスレショルド以下になったとき、さらに実施の形態３のようにしてもよい。このようにすると、実施の形態４よりもさらに左右のバランス良く調整することができる。
【００４０】
実施の形態５．
図１５は、この発明の実施の形態５の電波軸調整装置の構成図である。図１５の電波軸調整装置は、図１の電波軸調整装置と電波反射手段４Ｌの替わりに電界強度計測部１４Ｌをアームの先端部に支持していることが異なっている。電界強度計測部１４Ｌは、電界強度計測アンテナ、ホーン、ダイポールなど空間の電界強度を計測できるものであればなんでもよい。その他の構成は同様であるので説明は省略する。さらに電波軸の軸調整の手順も図２のＳ１２、Ｓ２２、Ｓ２７において、送受信手段１で受信された反射電波の電界を計測する替わりに電界強度計測部で計測された電界強度を電界強度計測手段に入力することで調整を行うことができる。
【００４１】
この電波軸調整装置は、電界強度計測部１４Ｌで計測した電界強度が反射波の電界強度に比べて大きいので、高い精度で送受信手段の電波軸１１と目標軸１３とを一致させることができる。
【００４２】
さらに、スレショルド値を設定してあるので、調整終了の判断が容易にできる。
【００４３】
さらに、スレショルド値として、あらかじめ計測した放射パターンの値から決めてあるので、スレショルド値以下になったと判断することによって調整の確実さが向上する。
【００４４】
実施の形態６．
図１６は、この発明の実施の形態６の電波軸調整装置の構成図である。図１６の電波軸調整装置と図５の電波軸調整装置との違いは、電波反射手段４Ｌ、４Ｒの替わりに電界強度計測部１４Ｌ、１４Ｒをアームの先端部に支持していることが異なっている。アームの図示は省略している。その他の構成は同様であるので説明は省略する。さらに電波軸の軸調整の手順も図６のＳ１１２、Ｓ１１７、Ｓ１２３、Ｓ１２８、Ｓ１３５、Ｓ１３９、Ｓ１４５、Ｓ１４９において、送受信手段１で受信された反射電波の電界を計測する替わりに電界強度計測部１４Ｌ、１４Ｒで計測された電界強度を電界強度計測手段に入力することで調整を行うことができる。なお、図５の電波軸調整装置では、電界強度の計測に際し、電波反射手段４Ｌ、４Ｒを電波吸収体で覆うこと必要であった。しかし、図１６の電波軸調整装置では、同時に電界強度計測部１４Ｌ、１４Ｒで計測できるので、図６のＳ１１０、Ｓ１１５、Ｓ１２１、Ｓ１２６、Ｓ１３３、Ｓ１３７、Ｓ１４３、Ｓ１４７の操作は必要ない。
【００４５】
この電波軸調整装置は、左右の電界強度計測部を用いるので、電波反射手段のように計測に際して覆うような煩雑な作業が必要なく、実施の形態５より精度よく送受信手段の電波軸１１と目標軸１３を一致させることができる。
【００４６】
さらに、左右の電界強度計測部で計測された電界強度をスレショルド値以下になるように調整するので、左右のバランス良く調整することができる。
実施の形態７．
この発明の実施の形態７の電波軸調整装置の軸調整手順は、実施の形態６に対して、さらに電界強度ＬＭとＲＭの差分の絶対値をあらかじめ設定した閾値と比較することである。この部分のフローチャートは、図９と同様である。但し、Ｓ１３３、Ｓ１３７、Ｓ１４３、Ｓ１４７は行わない。また電波の受信とその受信した電波の電界強度を求める手順は、電界強度計測部での測定に代替される。
【００４７】
このような電波軸調整装置は、送信波の左右の電界強度の差分をも小さくする調整をおこなうので、実施の形態６よりもさらに左右のバランス良くレーダ装置の電波軸１１と目標軸１３とを一致させることができる。
【００４８】
実施の形態８．
図１７は、この発明の実施の形態８の電波軸調整装置の構成図である。図１７の電波軸調整装置と図１０の電波軸調整装置との違いは、電波反射手段４Ｌ、４Ｒ、４Ｃの替わりに電界強度計測部１４Ｌ、１４Ｒ、１４Ｃをアームの先端部に支持していることが異なっている。アームの図示は省略している。その他の構成は同様であるので説明は省略する。さらに電波軸の軸調整の手順も図１１、図１２のＳ２１２、Ｓ２１７、Ｓ２２３、Ｓ２２８、Ｓ２３４、Ｓ２３８、Ｓ２４４、Ｓ２４８において、送受信手段１で受信された反射電波の電界を計測する替わりに電界強度計測部１４Ｌ、１４Ｒ、１４Ｃで計測された電界強度を電界強度計測手段に入力することで調整を行うことができる。なお、図１０の電波軸調整装置では、電界強度の計測に際し、電波反射手段４Ｌ、４Ｒ、４Ｃを電波吸収体で覆うこと必要であった。しかし、図１７の電波軸調整装置では、同時に電界強度計測部１４Ｌ、１４Ｒ、１４Ｃで計測できるので、図１１、図１２のＳ２１０、Ｓ２３２、Ｓ２３６、Ｓ２４２、Ｓ２４６の操作は必要ない。
【００４９】
このような電波軸調整装置は、送受信手段の車両への取付のずれが大きいときでも、電波軸１１と目標軸１３とを大まかに近づけることができる。その後、左右の電界強度計測部を用いて高い精度でレーダ装置の電波軸１１と目標軸１３を一致させることができる。
【００５０】
さらに、目標軸上に配設された電界強度計測部の電界強度をあらかじめ設定されたスレショルド値と比較することで、大まかに近づいたことを判断することができる。
【００５１】
さらに、スレショルド値として、あらかじめ計測された放射パターンの電波軸上の電界強度から求めているので、電波軸が目標軸に大まかに近づいたことが分かる。
なお、実施の形態１から８において車両に搭載された車載用レーダの電波軸を車両進行軸に一致させる電波軸調整装置について説明してきたが、構内など近距離通信用マイクロ波通信におけるマイクロ波アンテナの電波軸を送受信相互で合わせる際も同様な効果が得られる。
【００５２】
【発明の効果】
電波軸および上記電波軸とナル角度をなすナル軸を有し、電波を送受信する送受信手段と、上記送受信手段を上記送受信手段の中心点を中心に電波基準面内に回転させる軸調整機構と、上記送受信手段の放射パターンの電波軸が車両の目標軸上にあるときの放射パターンの左右のナル軸上に配設された電波反射手段と、上記送受信手段から送信された電波の上記電波反射手段での反射波の電界強度を計測する電界強度計測手段と、上記電界強度に基づいて、上記送受信手段の電波軸を上記目標軸に一致させるように上記軸調整機構を制御し上記送受信手段を回転させる電波軸調整手段とを有するので、電波軸の回転に対する電波反射手段で反射された反射波の電界強度の変化が極めて大きく、高い精度で容易にレーダ装置の電波軸と目標軸とを一致させることができる。
【図面の簡単な説明】
【図１】この発明の実施の形態１の電波軸調整装置のブロック図である。
【図２】図１の電波軸を調整する手順のフローチャートである。
【図３】図２のフローチャートを説明するための放射パターンと電波反射手段の位置関係図である。
【図４】図１の送受信手段の指向性パターン図である。
【図５】この発明の実施の形態２の電波軸調整装置のブロック図である。
【図６】図５の電波軸を調整する手順のフローチャートである。
【図７】図６のフローチャートを説明するための放射パターンと電波反射手段の位置関係図である。
【図８】図５の送受信手段の指向性パターン図である。
【図９】この発明の実施の形態３の電波軸調整装置の電波軸を調整する手順のフローチャートである。
【図１０】この発明の実施の形態４の電波軸調整装置のブロック図である。
【図１１】図１０の電波軸を調整する手順のフローチャートである。
【図１２】図１０の電波軸を調整する手順のフローチャートのつづきである。
【図１３】図１１のフローチャートを説明するための放射パターンと電波反射手段の位置関係図である。
【図１４】図１０の送受信手段の指向性パターン図である。
【図１５】この発明の実施の形態５の電波軸調整装置のブロック図である。
【図１６】この発明の実施の形態６の電波軸調整装置のブロック図である。
【図１７】この発明の実施の形態８の電波軸調整装置のブロック図である。
【符号の説明】
１送受信手段、２車両、３軸調整機構、４Ｃ、４Ｌ、４Ｒ電波反射手段、５制御手段、６発振手段、７電界強度計測手段、８電波軸調整手段、９Ｌアーム、１０表示手段、１１電波軸、１２Ｌ、１２Ｒナル軸、１３目標軸、１４Ｃ、１４Ｌ、１４Ｒ電界強度計測部。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a radio wave axis adjustment device for an in-vehicle radar device that detects a measurement target by receiving a radio wave reflected by the measurement target of a transmitted radio wave and calculates a distance, a relative speed, and an angle to the measurement target.
[0002]
[Prior art]
In a conventional on-vehicle radar device, the direction in which the electric field strength is strongest (hereinafter referred to as a radio wave axis) and the direction in which the vehicle travels (hereinafter referred to as a target axis) in the radiation pattern of the transmission / reception means provided therein. ), The detected angle of the object to be measured has an error, and the vehicle traveling in the adjacent lane is judged as the preceding vehicle, or the preceding vehicle is not judged as the preceding vehicle. There is a possibility of doing.
Therefore, in order to make the radio axis coincide with the target axis, an object to be detected is placed on the target axis, and the received electric field strength of the reflected radio wave from the detected object is measured, so that the received electric field intensity is maximized. There is a method for adjusting the radio wave axis (for example, see Patent Document 1).
[0003]
[Patent Document 1]
JP 7-81490 A
[0004]
[Problems to be solved by the invention]
However, in the radiation pattern of a general antenna (directive antenna) as a transmission / reception means used in an on-vehicle radar device, the received electric field strength with respect to a change in angle near the radio wave axis, that is, near the maximum point of electric field strength. The change is slight. For this reason, it is difficult to determine whether or not the electric field strength is maximized, and it is difficult to adjust the radio wave axis with high accuracy.
[0005]
An object of the present invention is to provide an on-vehicle radar device radio wave axis adjusting device that accurately adjusts a radio wave axis to a target axis.
[0006]
[Means for Solving the Problems]
A radio wave axis adjusting apparatus according to the present invention has a radio wave axis and a null axis that forms a null angle with the radio wave axis, and transmits / receives radio waves, and the radio wave reference centering on a center point of the transmit / receive means. A shaft adjusting mechanism that rotates in-plane; and Of the radiation pattern of the transmitting and receiving means Radio wave axis Vehicle When on the target axis Radiation pattern A radio wave reflecting means disposed on the left and right null axes; an electric field intensity measuring means for measuring the electric field intensity of the reflected wave at the radio wave reflecting means of the radio wave transmitted from the transmitting / receiving means; and ,the above Of sending and receiving means Radio wave axis adjusting means for controlling the axis adjusting mechanism to rotate the transmitting / receiving means so that the radio wave axis coincides with the target axis.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
1 is a block diagram of a radio wave axis adjusting apparatus according to Embodiment 1 of the present invention. FIG. 2 is a flowchart of a procedure for adjusting the radio wave axis of the transmission / reception antenna. FIG. 3 is a positional relationship diagram of the radiation pattern and the radio wave reflection means for explaining the flowchart of FIG. FIG. 4 is a directivity pattern diagram of the transmission / reception means of FIG.
[0008]
In this description, the radio wave axis adjustment device will be described for a case where the radio wave axis of a transmission / reception means of an in-vehicle radar device mounted on a vehicle is adjusted. The four wheels of the vehicle are brought into contact with the flat ground, and a plane parallel to the ground including the axle of the front wheel of the vehicle obtained at that time is used as a reference plane. The target axis is on this reference plane and is perpendicular to the front wheel axle. The center point of the transmission / reception antenna as the transmission / reception means is included in a plane (hereinafter referred to as a radio wave reference plane) that is separated from the reference plane by a predetermined height and parallel to the reference plane. The radiation pattern of the radio wave transmitted from the transmission / reception antenna is expressed in a polar coordinate system on the radio wave reference plane. In order to simplify the explanation, the reference plane and the radio wave reference plane are assumed to be parallel. However, when they are not parallel, the radio wave axis is adjusted to the target axis by adjusting the radio wave axis over two axes. Can do. The rotation direction of the radio wave axis is the direction when the vehicle is looked down from above.
[0009]
The radio wave axis adjusting device includes a transmission / reception unit 1 that transmits / receives radio waves, a shaft adjustment mechanism 3 that supports the transmission / reception unit 1 and is supported by a vehicle 2 so as to be rotatable around a center point of the transmission / reception unit 1 within a radio wave reference plane. The radio wave reflecting means 4L, which is separated from the center point of the transmission / reception means 1 by a predetermined distance RL and supported by the vehicle 2, and the control means 5 for controlling them are provided.
[0010]
The control means 5 includes an oscillating means 6 for sending a transmission signal toward the transmitting / receiving means 1, an electric field strength measuring means 7 for detecting the electric field strength of the radio wave received by the transmitting / receiving means 1, and an axis adjusting mechanism based on the electric field strength. And a radio wave axis adjusting means 8 for calculating the rotation angle 3 and instructing the axis adjusting mechanism 3.
[0011]
The transmission / reception means 1 is usually composed of a transmission / reception antenna or the like. The transmission / reception means 1 is supported by a shaft adjustment mechanism 3 in the vicinity of the front grill of the vehicle 2.
[0012]
The axis adjustment mechanism 3 includes an actuator so that the angle of the radio wave axis of the transmission / reception unit 1 can be adjusted within the radio wave reference plane with the center point of the transmission / reception unit 1 as the center. The actuator is composed of a motor or the like.
[0013]
The radio wave reflecting means 4L includes a corner reflector or the like. The radio wave reflecting means 4L is supported at one end by the vehicle 2 and supported by an arm 9L having a length RL. Before being attached to the vehicle 2, a radiation pattern indicating the directivity of the transmission / reception means 1 is measured in the anechoic chamber, and the radio wave axis 11 and the null point of the transmission / reception means 1 are obtained from the radiation pattern. FIG. 4 shows an example of the measured radiation pattern. The radio wave axis 11 of the transmission / reception means 1 is an axis that passes through the center point of the transmission / reception means 1 and indicates the direction in which the electric field strength is maximum. Further, the null point (NULL) is a direction indicating a state in which the electric field strength between the main lobe and the side lobe adjacent to the main lobe in the radiation pattern is close to the noise level. The null point is a direction rotated counterclockwise and clockwise from the radio wave axis 11 by a null angle (θL) as shown in FIG. The null axis 12L of the transmission / reception means 1 is an axis rotated counterclockwise from the radio wave axis 11 by a null angle (θL) toward the traveling direction of the vehicle.
[0014]
In order to determine whether or not the electric field intensity of the reflected wave reflected by the radio wave reflecting means 4L has become equal to or less than the value near the null point, the threshold value THL is set in advance in consideration of a margin with respect to the noise level. .
[0015]
The radio wave reflecting means 4L on the null axis 12L is a triangular pyramid corner reflector having a side of 110 mm. The radio wave reflecting means 4L is fixed to the tip of the arm 9L so that the reflection axis of the radio wave reflecting means 4L is substantially directed to the center point of the transmitting / receiving means 1.
[0016]
The oscillation means 6 is composed of an oscillator that transmits a millimeter wave in the 76.5 GHz band. The electric field strength measuring means 7 is composed of an electric field strength measuring device for extracting electric field components from the received 76.5 GHz band millimeter wave and measuring the strength. The radio wave axis adjusting means 8 outputs values of the rotation direction and the rotation angle of the axis adjustment mechanism 3 using a change in electric field strength and a preset threshold value THL based on a procedure described later. The radio wave axis adjusting means 8 is constituted by a computer, and values such as electric field intensity and angle are stored in a storage means (not shown in particular).
Further, the control unit 5 includes a display unit 10 that displays the received electric field strength LM. In addition, as a display format at this time, either digital display by numbers or analog display by swinging the pointer may be used.
[0017]
Next, a procedure for adjusting the radio wave axis 11 of the transmission / reception means 1 will be described with reference to FIG. In this description, as shown in FIG. 3, the radio wave axis 11 of the transmission / reception means 1 is rotated by θ in the counterclockwise direction toward the vehicle traveling direction with respect to the target axis 13 on the radio wave reference plane.
In step (hereinafter abbreviated as S) 10, the oscillating means 6 excites a predetermined signal and transmits radio waves from the transmitting / receiving means 1 in the traveling direction of the vehicle 2. In S 11, the transmission / reception unit 1 receives the reflected radio wave reflected by the radio wave reflection unit 4 L and transmits a reception signal to the electric field strength measurement unit 7. In S12, the electric field strength measuring means 7 measures the electric field strength LM of the received signal. In S13, the radio wave axis adjusting means 8 stores the electric field strength LM as the received electric field strength LM1. In S14, the radio wave axis adjusting means 8 controls the axis adjusting mechanism 3 and rotates the transmitting / receiving means 1 counterclockwise by an angle of 0.1 °. In S 15, the oscillating means 6 excites a predetermined signal and transmits radio waves from the transmitting / receiving means 1 in the traveling direction of the vehicle 2. In S 16, the transmission / reception unit 1 receives the reflected radio wave reflected by the radio wave reflection unit 4 L, and transmits a reception signal to the electric field strength measurement unit 7. In S17, the electric field strength measuring unit 7 measures the electric field strength LM of the received signal. In S18, the radio wave axis adjusting unit 8 stores the electric field strength LM as the received electric field strength LM2. In S19, the stored received electric field strengths LM1 and LM2 are compared. If LM1> LM2, it means that the rotation of the radio wave axis is still insufficient, so that the process proceeds to S20, and if LM1 <LM2, Since it means that the rotation direction of the shaft is opposite, the process proceeds to S25. In S20, the radio wave axis adjusting means 8 controls the axis adjusting mechanism 3 and rotates the transmitting / receiving means 1 counterclockwise by an angle of 0.1 °. In S 21, the oscillating means 6 excites a predetermined signal and transmits radio waves from the transmitting / receiving means 1 in the traveling direction of the vehicle 2. In S 22, the transmission / reception unit 1 receives the reflected radio wave reflected by the radio wave reflection unit 4 L and transmits a reception signal to the electric field strength measurement unit 7. In S23, the electric field strength measuring means 7 measures the electric field strength LM of the received signal. In S24, the measured electric field strength LM is compared with a preset threshold THL (for example, the electric field strength is zero). If LM> THL, the process returns to S20, and if LM ≦ THL, the radio wave of the transmitting / receiving means is transmitted. It is determined that the axis matches the target axis, and the axis adjustment procedure is completed. In S25, the radio wave axis adjusting means 8 controls the axis adjusting mechanism 3 to rotate the transmitting / receiving means 1 clockwise by an angle of 0.1 °. In S 26, the oscillating means 6 excites a predetermined signal and transmits radio waves from the transmitting / receiving means 1 in the traveling direction of the vehicle 2. In S 27, the transmission / reception unit 1 receives the reflected radio wave reflected by the radio wave reflection unit 4 L, and transmits the received signal to the electric field strength measurement unit 7. In S28, the electric field strength measuring means 7 measures the electric field strength LM of the received signal. In S29, the measured electric field strength LM is compared with a preset threshold THL (for example, the electric field strength is zero). If LM> THL, the process returns to S25. It is determined that the axis matches the target axis, and the axis adjustment procedure is completed.
[0018]
In such a radio wave axis adjusting device, the change in the electric field intensity of the reflected wave from the radio wave reflecting means with respect to the rotation angle of the radio wave axis is large, so that the radio wave axis of the transmitting / receiving means and the target axis can be easily matched with high accuracy. it can.
[0019]
Furthermore, since the threshold value is set in advance, it can be easily determined that the radio wave axis 11 and the target axis 13 coincide.
[0020]
Furthermore, since the threshold value is set to zero, it can be seen that the null point of the radiation pattern is surely facing the radio wave reflecting means.
[0021]
Even if the radio wave axis of the transmission / reception unit is shifted in the clockwise direction with respect to the target axis, the radio wave axis 11 of the transmission / reception unit and the target axis 13 can be made to coincide with each other by the same method as in the first embodiment.
[0022]
Furthermore, since the radio wave reflecting means 4L that is an object to be detected is not arranged on the target axis, the vehicle being manufactured can be started as it is, and the line tact of the manufacturing line is not deteriorated.
[0023]
Further, as the radio wave reflecting means 4L, a normal scattering cross section of 10 m ² However, since a large structure cannot be arranged in the production line, the structure can be reduced in size by using the radio wave reflecting means 4L as a corner reflector.
[0024]
Embodiment 2. FIG.
FIG. 5 is a block diagram of a radio wave axis adjusting apparatus according to Embodiment 2 of the present invention. FIG. 6 is a flowchart showing the axis adjustment procedure of FIG. FIG. 7 is a relationship diagram between a radiation pattern and a target axis. FIG. 8 shows a radiation pattern. The radio wave axis adjusting device of FIG. 5 is different from the radio wave axis adjusting device of FIG. 1 in that the radio wave reflecting means is further increased from one to two, and the other is the same. The arm is omitted. Description of similar parts is omitted. The radio wave reflecting means 4R is supported by an arm at a position away from the center point of the transmitting / receiving means 1 by a distance RR. Further, the radio wave reflecting means 4R has a null shaft 12 rotated clockwise from the target shaft 13 toward the vehicle traveling direction by a NULL angle (θR). R It is arranged on the top.
In the second embodiment, one of the radio wave reflecting means 4L and 4R is covered with a radio wave absorber to reduce radio wave reflection. This radio wave absorber comprises a radio wave absorption film in which magnetic metal fine powder and rubber are integrated, and a metal foil adhered to the back surface of the radio wave absorption film.
The threshold value THR is a value obtained by adding a margin to the noise level, similar to THL.
[0025]
Next, the procedure for adjusting the radio wave axis 11 of the transmission / reception means 1 in the second embodiment will be described with reference to FIG. In this description, the radio wave axis 11 of the transmitting / receiving means 1 is rotated by θ in the counterclockwise direction toward the vehicle traveling direction with respect to the target axis on the radio wave reference plane as shown in FIG.
In S110, the right radio wave reflecting means 4R is covered with a radio wave absorber. In S 111, the oscillating means 6 excites a predetermined signal and transmits radio waves from the transmitting / receiving means 1 in the traveling direction of the vehicle 2. In S 112, the transmission / reception unit 1 receives the reflected radio wave reflected by the left radio wave reflection unit 4 L and transmits a reception signal to the electric field strength measurement unit 7. In S113, the electric field strength measuring means 7 measures the electric field strength LM of the received signal. In S114, the radio wave axis adjusting unit 8 stores the electric field strength LM as the received electric field strength LM1. In S115, the left radio wave reflecting means 4L is covered with a radio wave absorber. In S 116, the oscillating means 6 excites a predetermined signal and transmits radio waves from the transmitting / receiving means 1 in the traveling direction of the vehicle 2. In S 117, the transmission / reception unit 1 receives the reflected radio wave reflected by the right radio wave reflection unit 4 R and transmits the received signal to the electric field strength measurement unit 7. In S118, the electric field strength measuring unit 7 measures the electric field strength RM of the received signal. In S119, the radio wave axis adjusting unit 8 stores the electric field strength RM as the received electric field strength RM1. In S120, the radio wave axis adjusting means 8 controls the axis adjusting mechanism 3 to rotate the transmitting / receiving means 1 counterclockwise by an angle of 0.1 °. In S121, the right radio wave reflecting means 4R is covered with a radio wave absorber. In S122, the oscillating means 6 excites a predetermined signal and transmits radio waves from the transmitting / receiving means 1 in the traveling direction of the vehicle 2. In S123, the transmission / reception means 1 receives the reflected radio wave reflected by the left radio wave reflection means 4L, and transmits the received signal to the electric field strength measurement means 7. In S124, the electric field strength measuring means 7 measures the electric field strength LM of the received signal. In S125, the radio wave axis adjusting unit 8 stores the electric field strength LM as the received electric field strength LM2. In S126, the left radio wave reflecting means 4L is covered with a radio wave absorber. In S127, the oscillating means 6 excites a predetermined signal and transmits radio waves from the transmitting / receiving means 1 in the traveling direction of the vehicle 2. In S128, the transmission / reception means 1 receives the reflected radio wave reflected by the right radio wave reflection means 4R and transmits the received signal to the electric field strength measurement means 7. In S129, the electric field strength measuring unit 7 measures the electric field strength RM of the received signal. In S130, the radio wave axis adjusting means 8 stores the electric field strength RM as the received electric field strength RM2. In S131, the received reception field strengths LM1 and LM2 are compared, and RM1 and RM2 are further compared. If LM1> LM2 and RM1> RM2, this means that the rotation of the radio wave axis is still insufficient, so the process proceeds to S132, and if LM1 <LM2 and RM1 <RM2, the rotation direction of the radio wave axis is reversed. The process proceeds to S143. In S132, the radio wave axis adjusting means 8 controls the axis adjusting mechanism 3 to rotate the transmitting / receiving means 1 counterclockwise by an angle of 0.1 °. In S133, the right radio wave reflecting means 4R is covered with a radio wave absorber. In S 134, the oscillating means 6 excites a predetermined signal and transmits radio waves from the transmitting / receiving means 1 in the traveling direction of the vehicle 2. In S 135, the transmission / reception means 1 receives the reflected radio wave reflected by the left radio wave reflection means 4 L, and transmits the received signal to the electric field strength measurement means 7. In S136, the electric field strength measuring means 7 measures the electric field strength LM of the received signal. In S137, the left radio wave reflecting means 4L is covered with a radio wave absorber. In S 138, the oscillation unit 6 excites a predetermined signal and transmits a radio wave from the transmission / reception unit 1 in the traveling direction of the vehicle 2. In S 139, the transmission / reception means 1 receives the reflected radio wave reflected by the right radio wave reflection means 4 R and transmits the received signal to the electric field strength measurement means 7. In S140, the electric field strength measuring unit 7 measures the electric field strength RM of the received signal. In S141, the measured electric field strengths LM and RM are compared with preset thresholds THL and THR, respectively. If LM> THL and RM> THR, the process returns to S132, and if LM ≦ THL and RM ≦ THR, it is determined that the radio wave axis of the transmission / reception means 1 matches the target axis, and the axis adjustment procedure is completed. In S142, the radio wave axis adjusting means 8 controls the axis adjusting mechanism 3 to rotate the transmitting / receiving means 1 clockwise by an angle of 0.1 °. In S143, the right radio wave reflecting means 4R is covered with a radio wave absorber. In S 144, the oscillation unit 6 excites a predetermined signal and transmits a radio wave from the transmission / reception unit 1 in the traveling direction of the vehicle 2. In S 145, the transmission / reception unit 1 receives the reflected radio wave reflected by the left radio wave reflection unit 4 L, and transmits the received signal to the electric field strength measurement unit 7. In S146, the electric field strength measuring unit 7 measures the electric field strength LM of the received signal. In S147, the left radio wave reflecting means 4L is covered with a radio wave absorber. In S 148, the oscillating means 6 excites a predetermined signal and transmits radio waves from the transmitting / receiving means 1 in the traveling direction of the vehicle 2. In S 149, the transmission / reception means 1 receives the reflected radio wave reflected by the right radio wave reflection means 4 R, and transmits the received signal to the electric field strength measurement means 7. In S150, the electric field strength measuring unit 7 measures the electric field strength RM of the received signal. In S151, the measured electric field strengths LM and RM are compared with preset thresholds THL and THR, respectively. If LM> THL and RM> THR, the process returns to S132, and if LM ≦ THL and RM ≦ THR, it is determined that the radio wave axis of the transmission / reception means 1 matches the target axis, and the axis adjustment procedure is completed.
[0026]
The radio wave reflection means is hidden by the radio wave absorber so that the electric field strength is not received from other radio wave reflectors, but the radio wave reflection means may be replaced and measured.
[0027]
Even if the radio wave axis 11 of the radiation pattern is shifted to the right with respect to the target axis 13, the radio wave axis 11 of the radar apparatus and the target axis 13 can be made to coincide with each other by the same method.
[0028]
Since this radio wave axis adjusting device is provided with radio wave reflection means on the left and right null axes, even when only one radio wave reflection means is used, a change is seen in either of the reflected waves even when there is little change. Therefore, the radio wave axis 11 and the target axis 13 of the radar apparatus can be made to coincide with each other with higher accuracy than in the first embodiment.
[0029]
Furthermore, since threshold values are set for the left and right electric field strengths, the left and right electric field strengths can be adjusted with a good balance.
[0030]
Embodiment 3 FIG.
FIG. 9 is a flowchart of the axis adjustment procedure of the radio wave axis adjustment apparatus according to Embodiment 3 of the present invention. Note that the steps up to S151 are the same as those in FIG. 6, and only S181 and S182 are different. In S142, when the electric field strengths LM and RM are smaller than the thresholds THL and THR, respectively, in S181, an absolute value of the difference between LM and RM is further obtained, and the value is compared with a preset threshold value ΔB. When the absolute value is smaller than the threshold value, it is determined that the axis adjustment has been completed. When the absolute value is larger than the threshold value, the process returns to S132 to rotate the shaft. In S182, the same operation as in S181 is performed. When the absolute value of the difference between LM and RM is larger than the threshold value ΔB, the process returns to S142 and the axis adjustment is continued.
[0031]
Such a radio wave axis adjusting device performs adjustment to reduce the difference between the electric field intensities of the left and right reflected waves, so that the radio wave axis 11 and the target axis 13 of the radar device are more balanced in the left and right directions than in the second embodiment. Can be matched.
[0032]
Embodiment 4 FIG.
FIG. 10 is a block diagram of a radio wave axis adjusting apparatus according to Embodiment 4 of the present invention. 11 and 12 are flowcharts showing the axis adjustment procedure of FIG. FIG. 13 is a relationship diagram between a radiation pattern and a target axis for explaining the fourth embodiment. FIG. 14 shows a radiation pattern. The radio wave axis adjusting device of FIG. 10 is different from the radio wave axis adjusting device of FIG. 5 in that the radio wave reflecting means is further increased from two to three, and the other is the same. Description of similar parts is omitted. In the flowchart of FIG. 12, S231 to S240 are the same as S132 to S141 and S241 to S250 are the same as S142 to S151 in FIG. The radio wave reflecting means 4C is supported by an arm at a position separated from the center point of the transmitting / receiving means 1 by a distance RC. Further, the radio wave reflecting means 4C is supported on the target axis 13.
The first threshold value is a value THC corresponding to the electric field strength CM of the reflected wave reflected by the radio wave reflecting means 4C arranged on the target axis, and THC is the electric field on the radio axis of the radiation pattern measured in advance. The value obtained from the strength. This THC is set in order to determine that the radio wave axis is close to the target axis. Furthermore, as the second threshold value, the threshold values THL and THR of the second embodiment are set to zero.
[0033]
Hereinafter, the shaft adjusting procedure of the fourth embodiment will be described with reference to FIGS. In this description, the radio wave axis 11 of the transmitting / receiving means 1 is rotated by θ in the counterclockwise direction toward the vehicle traveling direction with respect to the target axis on the radio wave reference plane as shown in FIG.
[0034]
In S210, the left and right radio wave reflecting means 4L, 4R are covered with a radio wave absorber. In S 211, the oscillating means 6 excites a predetermined signal and transmits radio waves from the transmitting / receiving means 1 in the traveling direction of the vehicle 2. In S212, the transmission / reception means 1 receives the reflected radio wave reflected by the central radio wave reflection means 4C, and transmits the received signal to the electric field strength measurement means 7. In S213, the electric field strength measuring means 7 measures the electric field strength CM of the received signal. In S214, the radio wave axis adjusting unit 8 stores the electric field strength CM as the received electric field strength CM1. In S215, the radio wave axis adjusting means 8 controls the axis adjusting mechanism 3 to rotate the transmitting / receiving means 1 counterclockwise by an angle of 0.1 °. In S 216, the oscillating means 6 excites a predetermined signal and transmits radio waves from the transmitting / receiving means 1 in the traveling direction of the vehicle 2. In S217, the transmission / reception means 1 receives the reflected radio wave reflected by the central radio wave reflection means 4C, and transmits the received signal to the electric field strength measurement means 7. In S218, the electric field strength measuring means 7 measures the electric field strength CM of the received signal. In S219, the radio wave axis adjusting unit 8 stores the electric field strength CM as the received electric field strength CM2. In S220, the received reception field strengths CM1 and CM2 are compared. If CM1 <CM2, it means that the rotation of the radio wave axis is still insufficient, so the process proceeds to S221. If CM1> CM2, it means that the rotation direction of the radio wave axis is opposite, and therefore, the process proceeds to S226. . In S221, the radio wave axis adjusting unit 8 controls the axis adjusting mechanism 3 to rotate the transmitting / receiving unit 1 counterclockwise by an angle of 0.1 °. In S222, the oscillating means 6 excites a predetermined signal and transmits radio waves from the transmitting / receiving means 1 in the traveling direction of the vehicle 2. In S223, the transmission / reception means 1 receives the reflected radio wave reflected by the central radio wave reflection means 4C, and transmits the received signal to the electric field strength measurement means 7. In S224, the electric field strength measuring means 7 measures the electric field strength CM of the received signal. In S225, the measured electric field strength CM is compared with a preset threshold THC. If CM <THC, the process returns to S221. If CM ≧ THC, the radio wave axis of the transmission / reception means 1 roughly matches the target axis. The process proceeds to S231. In S226, the radio wave axis adjusting unit 8 controls the axis adjusting mechanism 3 to rotate the transmitting / receiving unit 1 clockwise by an angle of 0.1 °. In S227, the oscillating means 6 excites a predetermined signal and transmits radio waves from the transmitting / receiving means 1 in the traveling direction of the vehicle 2. In S228, the transmission / reception means 1 receives the reflected radio wave reflected by the central radio wave reflection means 4C, and transmits the received signal to the electric field strength measurement means 7. In S229, the electric field strength measuring means 7 measures the electric field strength CM of the received signal. In S230, the measured electric field strength CM is compared with a preset threshold THC. If CM <THC, the process returns to S226. If CM ≧ THC, the radio wave axis of the transmission / reception means 1 and the target axis roughly match. And proceed to S241. In S231 to S240 and S241 to S250, the central radio wave reflecting means 4C is covered with a radio wave absorber, and the axis adjustment is further finely performed using the left and right radio wave absorbing means 4L and 4R.
[0035]
Even if the radio wave axis 11 of the radiation pattern AP is shifted to the right with respect to the target axis 13, the radio wave axis 11 of the radar apparatus and the target axis 13 can be made to coincide with each other by the same method as in the above embodiment.
[0036]
In this radio wave axis adjusting device, the central radio wave reflecting means 4C is additionally arranged on the target axis 13, and the radio wave axis 11 is rotated so that the received electric field strength CM becomes equal to or higher than the threshold THC. Even in this case, the radio wave axis 11 and the target axis 13 can be matched.
[0037]
Further, since a threshold value is set for the electric field intensity of the reflected wave reflected from the radio wave reflecting means 4C on the target axis 13, it can be determined that the vicinity of the null axis has been approached, and It is possible to shift to adjustment using the radio wave reflecting means 4L, 4R.
[0038]
Furthermore, since the threshold value is obtained from the electric field strength on the radio wave axis of the radiation pattern measured in advance, it can be seen that the radio wave axis is roughly approaching the target axis.
[0039]
Further, when the electric field intensity of the reflected wave reflected from the left and right radio wave reflecting means 4L, 4R is equal to or lower than the threshold, it may be further configured as in the third embodiment. In this way, the left and right balance can be adjusted with a better balance than in the fourth embodiment.
[0040]
Embodiment 5. FIG.
FIG. 15 is a block diagram of a radio wave axis adjusting apparatus according to Embodiment 5 of the present invention. The radio wave axis adjusting device of FIG. 15 is different from the radio wave axis adjusting device of FIG. 1 in that an electric field strength measuring unit 14L is supported at the tip of the arm instead of the radio wave reflecting means 4L. The electric field intensity measuring unit 14L may be anything that can measure the electric field intensity in a space, such as an electric field intensity measuring antenna, a horn, or a dipole. Since other configurations are the same, description thereof is omitted. In addition, the procedure for adjusting the axis of the radio wave axis is not limited to measuring the electric field of the reflected radio wave received by the transmission / reception means 1 in S12, S22, and S27 of FIG. You can make adjustments by entering
[0041]
In this radio wave axis adjusting device, since the electric field intensity measured by the electric field intensity measuring unit 14L is larger than the electric field intensity of the reflected wave, the radio wave axis 11 and the target axis 13 of the transmitting / receiving means can be matched with high accuracy.
[0042]
Furthermore, since the threshold value is set, it is possible to easily determine the end of the adjustment.
[0043]
Further, since the threshold value is determined from the value of the radiation pattern measured in advance, the certainty of adjustment is improved by determining that the threshold value is equal to or less than the threshold value.
[0044]
Embodiment 6 FIG.
FIG. 16 is a block diagram of a radio wave axis adjusting apparatus according to Embodiment 6 of the present invention. The difference between the radio wave axis adjusting device of FIG. 16 and the radio wave axis adjusting device of FIG. 5 is that the electric field intensity measuring units 14L and 14R are supported at the tip of the arm instead of the radio wave reflecting means 4L and 4R. Yes. The illustration of the arm is omitted. Since other configurations are the same, description thereof is omitted. Furthermore, the procedure for adjusting the axis of the radio wave axis is not limited to the measurement of the electric field of the reflected radio wave received by the transmitting / receiving means 1 in S112, S117, S123, S128, S135, S139, S145, and S149 in FIG. , 14R can be adjusted by inputting the electric field strength measured by 14R to the electric field strength measuring means. In the radio wave axis adjusting apparatus of FIG. 5, it is necessary to cover the radio wave reflecting means 4L, 4R with a radio wave absorber when measuring the electric field strength. However, since the radio field axis adjusting device of FIG. 16 can be measured simultaneously by the electric field intensity measuring units 14L and 14R, the operations of S110, S115, S121, S126, S133, S137, S143, and S147 of FIG. 6 are not necessary.
[0045]
Since this radio wave axis adjusting device uses the left and right electric field strength measuring units, there is no need for a complicated operation to cover the measurement as in the radio wave reflecting means, and the radio wave axis 11 and the target of the transmitting / receiving means are more accurate than in the fifth embodiment. The axis 13 can be matched.
[0046]
Furthermore, since the electric field intensity measured by the left and right electric field intensity measuring units is adjusted to be equal to or lower than the threshold value, it is possible to adjust with a good balance between the left and right.
Embodiment 7 FIG.
The axis adjustment procedure of the radio wave axis adjusting apparatus according to the seventh embodiment of the present invention is to compare the absolute value of the difference between the electric field strengths LM and RM with a preset threshold value as compared with the sixth embodiment. The flowchart of this part is the same as FIG. However, S133, S137, S143, and S147 are not performed. In addition, the procedure for receiving the radio wave and obtaining the electric field strength of the received radio wave is replaced with the measurement by the electric field strength measuring unit.
[0047]
Since such a radio wave axis adjusting device performs adjustment to reduce the difference between the left and right electric field strengths of the transmission wave, the radio wave axis 11 and the target axis 13 of the radar device are more balanced in the left and right directions than in the sixth embodiment. Can be matched.
[0048]
Embodiment 8 FIG.
FIG. 17 is a block diagram of a radio wave axis adjusting apparatus according to Embodiment 8 of the present invention. The radio wave axis adjusting device of FIG. 17 is different from the radio wave axis adjusting device of FIG. 10 in that the electric field intensity measuring units 14L, 14R, and 14C are supported at the tip of the arm instead of the radio wave reflecting means 4L, 4R, and 4C. Is different. The illustration of the arm is omitted. Since other configurations are the same, description thereof is omitted. Further, the procedure for adjusting the axis of the radio wave axis is not limited to measuring the electric field of the reflected radio wave received by the transmission / reception means 1 in S212, S217, S223, S228, S234, S238, S244, and S248 in FIGS. Adjustment can be performed by inputting the electric field strength measured by the measuring units 14L, 14R, and 14C to the electric field strength measuring means. In the radio wave axis adjusting apparatus of FIG. 10, it is necessary to cover the radio wave reflecting means 4L, 4R, 4C with a radio wave absorber when measuring the electric field strength. However, since the radio field axis adjusting device of FIG. 17 can simultaneously measure with the electric field intensity measuring units 14L, 14R, and 14C, the operations of S210, S232, S236, S242, and S246 of FIGS. 11 and 12 are not necessary.
[0049]
Such a radio wave axis adjusting device can bring the radio wave axis 11 and the target axis 13 closer to each other even when there is a large displacement of the transmission / reception means to the vehicle. Thereafter, the radio wave axis 11 and the target axis 13 of the radar apparatus can be matched with high accuracy using the left and right electric field intensity measuring units.
[0050]
Further, by comparing the electric field strength of the electric field strength measuring unit disposed on the target axis with a preset threshold value, it can be determined that the electric field strength has approached roughly.
[0051]
Furthermore, since the threshold value is obtained from the electric field strength on the radio wave axis of the radiation pattern measured in advance, it can be seen that the radio wave axis is roughly approaching the target axis.
In the first to eighth embodiments, the radio wave axis adjusting device that matches the radio wave axis of the in-vehicle radar mounted on the vehicle with the vehicle traveling axis has been described. However, the microwave antenna in the near field communication microwave communication such as a premises The same effect can be obtained when the radio wave axes are matched between transmission and reception.
[0052]
【The invention's effect】
A radio wave axis and a null axis that forms a null angle with the radio wave axis, a transmission / reception unit that transmits / receives radio waves, and an axis adjustment mechanism that rotates the transmission / reception unit around a center point of the transmission / reception unit within a radio wave reference plane; the above Of the radiation pattern of the transmitting and receiving means Radio wave axis Vehicle When on the target axis Radiation pattern A radio wave reflecting means disposed on the left and right null axes; an electric field intensity measuring means for measuring the electric field intensity of the reflected wave at the radio wave reflecting means of the radio wave transmitted from the transmitting / receiving means; and ,the above Of sending and receiving means And a radio wave axis adjusting means for controlling the axis adjusting mechanism to rotate the transmitting / receiving means so that the radio wave axis coincides with the target axis, so that the electric field intensity of the reflected wave reflected by the radio wave reflecting means with respect to the rotation of the radio wave axis Is extremely large, and the radio wave axis and the target axis of the radar apparatus can be easily matched with high accuracy.
[Brief description of the drawings]
FIG. 1 is a block diagram of a radio wave axis adjusting apparatus according to a first embodiment of the present invention.
FIG. 2 is a flowchart of a procedure for adjusting a radio wave axis in FIG. 1;
FIG. 3 is a positional relationship diagram between a radiation pattern and radio wave reflection means for explaining the flowchart of FIG. 2;
4 is a directivity pattern diagram of the transmission / reception means of FIG. 1. FIG.
FIG. 5 is a block diagram of a radio wave axis adjusting apparatus according to Embodiment 2 of the present invention.
6 is a flowchart of a procedure for adjusting the radio wave axis of FIG. 5;
7 is a positional relationship diagram between a radiation pattern and radio wave reflecting means for explaining the flowchart of FIG. 6; FIG.
FIG. 8 is a directivity pattern diagram of the transmission / reception means of FIG.
FIG. 9 is a flowchart of a procedure for adjusting the radio wave axis of the radio wave axis adjusting apparatus according to the third embodiment of the present invention.
FIG. 10 is a block diagram of a radio wave axis adjusting apparatus according to Embodiment 4 of the present invention.
11 is a flowchart of a procedure for adjusting the radio wave axis of FIG. 10;
FIG. 12 is a continuation of the flowchart of the procedure for adjusting the radio wave axis of FIG.
13 is a positional relationship diagram between a radiation pattern and radio wave reflection means for explaining the flowchart of FIG.
14 is a directivity pattern diagram of the transmission / reception means of FIG. 10. FIG.
FIG. 15 is a block diagram of a radio wave axis adjusting apparatus according to a fifth embodiment of the present invention.
FIG. 16 is a block diagram of a radio wave axis adjusting apparatus according to a sixth embodiment of the present invention.
FIG. 17 is a block diagram of a radio wave axis adjusting apparatus according to an eighth embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Transmission / reception means, 2 Vehicles, 3 axis adjustment mechanism, 4C, 4L, 4R Radio wave reflection means, 5 Control means, 6 Oscillation means, 7 Electric field strength measurement means, 8 Radio wave axis adjustment means, 9L arm, 10 Display means, 11 radio waves Axis, 12L, 12R Null axis, 13 Target axis, 14C, 14L, 14R Electric field intensity measurement unit.

Claims

A transmission / reception means having a radio wave axis and a null axis that forms a null angle with the radio wave axis;
An axis adjustment mechanism for rotating the transmission / reception means in a radio wave reference plane around the center point of the transmission / reception means;
Radio wave reflecting means disposed on the left and right null axes of the radiation pattern when the radio wave axis of the radiation pattern of the transmitting / receiving means is on the target axis of the vehicle ;
Electric field strength measuring means for measuring the electric field strength of the reflected wave at the radio wave reflecting means of the radio wave transmitted from the transmitting / receiving means;
Radio wave axis adjustment comprising: a radio wave axis adjusting means for controlling the axis adjusting mechanism so as to make the radio wave axis of the transmission / reception means coincide with the target axis based on the electric field strength and rotating the transmission / reception means. apparatus.

2. The radio wave axis adjusting apparatus according to claim 1, wherein the radio wave reflecting means is further disposed on the target axis.

The radio wave axis adjusting device according to claim 1 or 2, wherein the radio wave reflecting means comprises a corner reflector.

When the electric field intensity of the reflected wave reflected from the left and right radio wave reflecting means respectively disposed on the left and right null axes is smaller than a preset threshold value, the radio wave axis adjusting means is the transmitting / receiving means. The radio-wave axis adjusting apparatus according to claim 1, wherein the radio-wave axis is determined to be coincident with the target axis.

The radio wave axis adjusting means is configured such that the electric field strength of the reflected wave reflected from the radio wave reflecting means respectively disposed on the left and right null axes is smaller than a preset threshold value and the difference between the electric field strengths. 2. The radio-wave axis adjusting apparatus according to claim 1, wherein when the absolute value of is less than a preset threshold value, it is determined that the radio-wave axis of the transmission / reception means coincides with the target axis.

The radio axis adjusting means, when the electric field intensity of the reflected wave reflected from said radio wave reflecting means disposed on the target axis is greater than the first threshold value set beforehand, radio axis of the receiving means And the target axis substantially coincide with each other, and the electric field intensity of the reflected wave reflected from the radio wave reflecting means respectively disposed on the left and right null axes is set to a second threshold value set in advance. 3. The radio wave axis adjusting apparatus according to claim 2, wherein when both are smaller, it is determined that the radio wave axis of the transmission / reception means coincides with the target axis.

The radio axis adjusting means, when the electric field intensity of the reflected wave reflected from said radio wave reflecting means disposed on the target axis is greater than the first threshold value set beforehand, radio axis of the receiving means And the target axis substantially coincide with each other, and the electric field intensity of the reflected wave reflected from the radio wave reflecting means respectively disposed on the left and right null axes is set to a second threshold value set in advance. 3. The radio wave axis of the transmission / reception means and the target axis are determined to coincide with each other when both are smaller and the absolute value of the difference in electric field strength is smaller than a preset threshold value. Radio wave axis adjustment device.

A transmission / reception means having a radio wave axis and a null axis that forms a null angle with the radio wave axis;
An axis adjustment mechanism for rotating the transmission / reception means within a radio wave reference plane around the center point of the transmission / reception means;
An electric field strength measurement that is arranged on the left and right null axes of the radiation pattern when the radio wave axis of the radiation pattern of the transmission / reception means is on the target axis of the vehicle, and measures the electric field strength of the transmission wave transmitted from the transmission / reception means. And
A radio wave axis adjusting means for controlling the axis adjusting mechanism to rotate the transmitting / receiving means so that the radio wave axis of the transmitting / receiving means and the target axis coincide with each other based on the electric field intensity; Axis adjustment device.

9. The radio wave axis adjusting apparatus according to claim 8, wherein the electric field intensity measuring unit is further disposed on the target axis.

When the electric field intensity measured by the electric field intensity measuring unit respectively disposed on the left and right null axes is smaller than a preset threshold value, the radio wave axis adjusting means is connected to the radio wave axis of the transmitting / receiving means. 9. The radio wave axis adjusting apparatus according to claim 8, wherein it is determined that the target axis matches.

The radio wave axis adjusting means is configured such that the electric field intensity measured by the electric field intensity measuring unit provided on each of the left and right null axes is smaller than a preset threshold value and the absolute difference between the electric field intensity is absolute. 9. The radio wave axis adjusting apparatus according to claim 8, wherein when the value is smaller than a preset threshold value, it is determined that the radio wave axis of the transmission / reception means coincides with the target axis.

The radio wave axis adjustment means is configured to receive a radio wave of the transmission / reception means when the electric field intensity of the transmission wave measured by the electric field intensity measurement unit disposed on the target axis is greater than a preset first threshold value. It is determined that the axis and the target axis substantially coincide with each other, and the electric field intensity measured by the electric field intensity measuring unit provided on each of the left and right null axes is based on a preset second threshold value. 10. The radio wave axis adjusting apparatus according to claim 9, wherein when both are small, it is determined that the radio wave axis of the transmission / reception means coincides with the target axis.

The radio wave axis adjustment means is configured to receive a radio wave of the transmission / reception means when the electric field intensity of the transmission wave measured by the electric field intensity measurement unit disposed on the target axis is greater than a preset first threshold value. It is determined that the axis and the target axis substantially coincide with each other, and the electric field intensity measured by the electric field intensity measuring unit provided on each of the left and right null axes is based on a preset second threshold value. 10. The method according to claim 9, wherein when both are small and the absolute value of the difference between the electric field strengths is smaller than a preset threshold value, it is determined that the radio wave axis of the transmission / reception means matches the target axis. Radio wave axis adjustment device.

The radio wave axis adjusting device according to any one of claims 1 to 13, wherein the transmission / reception means is provided in an on-vehicle radar device, and the target axis is a vehicle traveling axis.