摘要:
A glass antenna has a rectangular loop antenna element which is extended on the upper region of a windshield glass where no heating wires of a defogger are arranged, and is capacitively coupled to the uppermost heating wire of the defogger at a predetermined capacitance, and a T-shaped second antenna element which is arranged on a region where the defogger is arranged, and is capacitively coupled to the uppermost heating wire of the defogger.
摘要:
An antenna array is disclosed in which a central vertical mast supports four radially extending struts. One loop of conducting elements, the director, is supported on the mast above the struts, on the mast below the struts and at the centrifugal end of two adjacent struts. A second loop of conducting elements, the reflector, is also supported on the mast above the struts and on the mast below the struts, and at the centrifugal end of the other two remaining struts. When the length of the director loop is smaller than the reflector loop and the reflector and director are both driven 180.degree. out-of-phase of each other, the antenna functions similarly to a Swiss Quad antenna, but has structural and weather-resistant advantages over the Swiss Quad.
摘要:
Multi-beam antennas with relatively large effective apertures for high antenna gain are provided for tower or pole mounting for cellular and other uses. Low wind resistance is achieved by use of thin cylindrical radiating units and thin cylindrical tuned reflector units. Each radiating unit includes separately excited upper and lower radiators, each including a microstrip pattern of a phase reversed series of half-wave transmission line sections on a substrate enclosed in a fiberglass tube radome. Each tuned reflector unit includes a resonant stack of electrically isolated metal rods enclosed in a fiberglass radome. In one embodiment, four cylindrical radiating units, each including upper and lower radiators, are laterally spaced in front of upper and lower reflector configurations, each including seven laterally spaced tuned reflector units. Four beams are provided by a beam forming network arranged to couple antenna element signal feeds to the four upper radiators and corresponding reverse phase signal feeds to the four lower radiators.
摘要:
The present invention relates to an antenna apparatus emitting or receiving high frequency waves and comprising four parasitic vertical rod elements disposed symmetrically to a central vertical rod element and switching elements controlled by a control circuit so that the parasitic rod elements are applied successively and periodically to the ground potential by the control circuit.
摘要:
An omnidirectional circularly polarized transmitting antenna employing a single row of slot antennas mounted on a metal support tube and a single row of dipole antennas mounted between the slots and a narrow vertical metal member parallel to the dipoles, the slot and dipole antennas each excite parasitic end-fire directors to control radiation patterns and phase centers.
摘要:
A transmitting antenna assembly comprises elementary driven antenna elements and generally radially extending fins mounted on a conventional supporting structure to obtain an omnidirectional or other desired antenna pattern, even for supporting structures of relatively large transverse dimensions.
摘要:
There is disclosed an antenna structure utilizing a loop having an annular ring coupled thereto and lying in a substantially horizontal plane transverse to the plane of the loop. The ring has reflector and director elements mounted thereon, and on opposite sides of the ring to offer increased directivity to the structure. A pair of dipoles are also utilized in the antenna structure. The dipoles are mounted on a first rotatable base assembly and the loop is mounted on a second rotatable base assembly. These base assemblies are rotatable with respect to a fixed base member and are controlled in rotation by means of a knob to permit azimuth orientation of the antennas.
摘要:
IN A TACAN BEACON ANTENNA, A MONOPOLE RADIATOR SURROUNDED BY TWO OR MORE CONCENTIC CIRCULAR ARRAYS OF PARASITIC ELEMENTS, WHICH ELEMENTS ARE DIGITALLY INHIBITED IN SEQUENCE IN A PREDETERMINED MANNER, IS USED TO PRODUCE A ROTATING RADIATION PATTERN CAPABLE OF PRODUCING 15 AND 135 CYCLE-PER-SECOND SIGNALS AT A RECEIVER. PARASITIC ELEMENTS ARE INHIBITED BY BEING OPEN CIRCUITED BY DIGITALLY CONTROLLED SWITCHING DIODES. RECIRCULATING SHIFT REGISTERS ARE USED TO INHIBIT PARASITIC ELEMENTS IN THE CIRCULAR ARRAYS TO PRODUCE THE REQUIRED MODULATION RADIATION PATTERN. A COMMON CLOCK IS USED TO STEP SAID REGISTER ALONG TO PRODUCE THE DESIRED ROTATING PATTERN.