(US5787671-A)      The antenna has a pair of horizontal members (11,12) which are arranged parallel to each other. A vertical member (13) is connected to the horizontal members on both sides through a hinge. The connected vertical members and the horizontal members together form a quadrilateral structure.    An intermediate connection member (19) is connected to the horizontal members on the central position through the hinge. The intermediate connection member is arranged parallel to any of the vertical members.    ADVANTAGE -   Eases connection process. Improves design and mfg efficiency. Ensures smooth operation. Simplifies structure.    (US5992120-A)      The antenna has a pair of horizontal members (11,12) which are arranged parallel to each other. A vertical member (13) is connected to the horizontal members on both sides through a hinge. The connected vertical members and the horizontal members together form a quadrilateral structure.    An intermediate connection member (19) is connected to the horizontal members on the central position through the hinge. The intermediate connection member is arranged parallel to any of the vertical members.    ADVANTAGE -   Eases connection process. Improves design and mfg efficiency. Ensures smooth operation. Simplifies structure.    (US6202379-B1)      The antenna has a pair of horizontal members (11,12) which are arranged parallel to each other. A vertical member (13) is connected to the horizontal members on both sides through a hinge. The connected vertical members and the horizontal members together form a quadrilateral structure.    An intermediate connection member (19) is connected to the horizontal members on the central position through the hinge. The intermediate connection member is arranged parallel to any of the vertical members.    ADVANTAGE -   Eases connection process. Improves design and mfg efficiency. Ensures smooth operation. Simplifies structure.    (US2001005966-A1)      The antenna has a pair of horizontal members (11,12) which are arranged parallel to each other. A vertical member (13) is connected to the horizontal members on both sides through a hinge. The connected vertical members and the horizontal members together form a quadrilateral structure.    An intermediate connection member (19) is connected to the horizontal members on the central position through the hinge. The intermediate connection member is arranged parallel to any of the vertical members.    ADVANTAGE -   Eases connection process. Improves design and mfg efficiency. Ensures smooth operation. Simplifies structure.    (US2001005967-A1)      The antenna has a pair of horizontal members (11,12) which are arranged parallel to each other. A vertical member (13) is connected to the horizontal members on both sides through a hinge. The connected vertical members and the horizontal members together form a quadrilateral structure.    An intermediate connection member (19) is connected to the horizontal members on the central position through the hinge. The intermediate connection member is arranged parallel to any of the vertical members.    ADVANTAGE -   Eases connection process. Improves design and mfg efficiency. Ensures smooth operation. Simplifies structure.