Abstract: A car radar duplexing arrangement for permitting a ingle antenna to transmit and receive electromagnetic radiation, comprising a circular waveguide, a waveguide coupling arrangement for coupling energy between two conductive lines and said circular waveguide, wherein said two conductive lines comprise mutually orthogonal conductors disposed normally with respect to the waveguide axis, and each extending through a respective aperture in the wall of said waveguide, a polariser disposed within the waveguide for conversion of linear waves into circular waves and vice-versa, and an antenna feed in communication with the polariser to transmit and receive circular waves.

Abstract: In order for it to be possible to manufacture a transition with a cost-effective stamping or diecasting or cold-molding process or with a plastic injection-molding process with subsequent metal plating, at least one ridge situated in the waveguide, which reduces the waveguide cross section in the direction of the stripline, has a cross section which tapers conically in the direction of the stripline.

Abstract: According to the invention, a monostatic FMCW radar sensor for a vehicle for detecting objects is proposed in which at least one antenna feed in combination with a dielectric lens is embodied for both transmitting and receiving a corresponding echo signal. At least one antenna feed is connected to a ring mixer via a ratrace ring or double ratrace ring, so that an expensive circulator can be dispensed with. The high-frequency structure is advantageously embodied in planar microstrip form. A plurality of transmission and reception antennas are focused via one common lens.

Abstract: A radar transmitter/receiver arrangement for use, for example, in automotive vehicle control in which R.F. energy from a frequency modulated oscillator is applied to an antenna for transmission and to one input of a mixer by way of a rat-race device, and RF energy reflected from a target and received at the antenna is applied to another input of the mixer by way of the rat-race device.

Abstract: A polariser particularly suitable for use in receiving satellite television signals includes a ferrite rod located within a waveguide, a yoke co-extensive with the ferrite member and a coil wound around the yoke. The yoke preferably is "U" shaped and includes an arm which projects into the waveguide at the end of the ferrite rod remote from the input of the waveguide.