Abstract: In a read-in area on the ROM disc, there are two control-data areas, and the Disc Information recorded in each control-data area comprises a error correction code (ECC (Error Correcting Code) block that has the same contents times, and the control-data area where reproduction-control data is recorded is separated from the other control-data area by a distance greater than the width than the width in the radial direction of the largest black dot.

Abstract: A marker for positioning near a buried object wherein the marker can be detected to locate the buried object. The marker includes a passive resonant type antenna which becomes inoperative when the initial position for the buried marker is changed. A lead wire and/or a mercury switch that is a part of the antenna serve to make the antenna inoperative due to such change in the initial position of the marker.

Abstract: An antenna system for use in an automotive vehicle comprises a housing mounted on a body of the automotive vehicle and having at least a portion of an upper surface thereof made of a dielectric material which transmits radio waves, at least one planar antenna disposed rotatably within the housing to receive radio waves transmitted through the portion of the upper surface of the housing made of the dielectric material, and driving means for driving the planar antenna to effect scanning of a radio wave receiving direction to search for the radio wave receiving direction of higher sensitivity. The housing protects the antenna system and maintains the fine appearance of the automotive vehicle. Further, the housing has a shape like that of an air spoiler, which makes it possible to maintain the satisfactory aerodynamic characteristic of the automotive vehicle.

Abstract: When a portable communication equipment such as a cellular telephone is carried inside an automotive vehicle, there is a need for its antenna to be supported exterior to the vehicle frame but at the same time be easily detachable from the vehicle.The invention provides a mounting clamp assembly for removably supporting an antenna on the exterior side of a vehicle window, and includes circuit means extending over the top of the window for sending signals between the antenna and the equipment. The mounting clamp assembly is easily attached to or removed from the window and its operation does not interfere with either the operation of the electrical circuit or the opening or closing of the window.

Abstract: A wideband antenna with reduced diameter and volume compared to prior art tennas and having non-critical dimensions resulting in ease of manufacture and tolerance to damage in portable applications and during installation. In one embodiment the antenna is comprised of a vertical element, a number of equally spaced, equal length horizontal elements in the form of a disc and a number of equally spaced, equal length round plane elements in the form of a cone. The vertical and horizontal elements are connected to the inner conductor of a coaxial transmission line and the conical elements are connected to the outer conductor transmission line. In a second embodiment of the present invention, the vertical element is deleted and a parallel inductor is connected between the transmission line outer and inner conductors.

Abstract: A first planar printed circuit board and a second planar printed circuit board are assembled to intersect each other at right angles to each other. Each board includes a microstrip realization of a drooping dipole antenna. The realization comprises, for each planar board, two vertical parallel feed lines with a radiating element extending from each feed line. Each of the feed lines is fed 90.degree. out of phase with the other feed line on the same board.

Abstract: A primary radiator for circularly polarized wave in accordance with the present invention is equipped with conductor projections along the inner wall of the horn antenna in order to convert linearly polarized wave to circularly polarized wave within the horn antenna, without adapting the prior art generator of circularly polarized wave. Consequently, it becomes possible to reduce the axial length and the overall size of the radiator. Moreover, the conductor projections are constructed with their edge sections on the aperture end side of the horn antenna sloping down along the inner wall of the horn antenna, so that generation of higher order modes can be suppressed and a satisfactory directivity can be obtained.

Abstract: A polarized signal receiver waveguide assembly, or feedhorn, for receiving a selected one of linearly polarized electromagnetic signals in one waveguide of circular cross-section and for launching or transmitting the selected signal into a second waveguide, the axes of the waveguides being disposed at a right angle. The first waveguide has a closed end wall, formed as a hemispherical cavity having a hemispherical concave surface. A probe comprising a signal receiver portion disposed in a plane perpendicular to the axis of the first waveguide and a launch or transmitter portion having its axis perpendicular to the axis of the second waveguide has its launch or transmitter portion mounted in a controllably rotatable dielectric rod, such that rotation of the rod causes rotation of the signal receiver portion for alignment with a selected one of the polarized signals.

Abstract: A multilayer antenna aperture polarizer comprises a single continuous electrically conductive trace on a flexible thin dielectric strip, the trace being formed into a plurality of arrays of grid lines with adjacent arrays interconnected by shorting leads and with a ground lead connected to the last or end array. The strip and shorting leads are folded at the locations of the shorting leads to form a stack of plane parallel polarizer panels, each comprising an array on the strip, adjacent panels in the stack being spaced apart in a direction transversely of the planes of the panels by insulator spacers, respectively. The polarizer is inserted in front of the aperture of the antenna and the ground lead is electrically connected to the antenna frame for grounding the several arrays. The shorting and ground leads are located at the corners of the stack in the neutral or minimum field zone of the antenna.