Abstract: A wideband microwave detector includes: a first local oscillator outputting a first local oscillation output containing a basic wave component, a secondary high harmonic component and a tertiary high harmonic component and being swept within a predetermined frequency range; a first mixer performing frequency mixing of the first local oscillation output and an antenna input input through an antenna and outputting a first mixing output; a second local oscillator outputting a second local oscillation output; a second mixer performing frequency mixing of the first mixing output and the second local oscillation output for generating a second mixing output, a single frequency discriminator for detecting a specific frequency in a discrimination input, and mode selector switch alternately switching a single super heterodyne reception mode, in which the first mixing output of the first mixer is introduced into the frequency discriminator as the discrimination input and a double super heterodyne reception mode, in whic

Abstract: A microwave detector comprises a one side opened hollow member having a first portion and a second portion, a printed circuit board, on which a metal layer is formed on one side, the metal layer on the printed circuit board cooperating with the hollow member for forming a horn antenna at a position corresponding to the first portion and an oscillation cavity for housing a first local oscillator at a position corresponding to the second portion, the horn antenna including a throat portion communicated with the oscillation cavity, a first mixing circuit disposed in the throat portion, an intermediate frequency processing circuit formed on the other side of the printed circuit board and including a first intermediate frequency filter, a second mixing circuit and a second local oscillator, and means for establishing electrical connection between the first mixing circuit and the intermediate frequency processing circuit across the printed circuit board.

Abstract: A structure of a reception frequency converting portion of a multi-band microwave detector, and including a microwave circuit comprises a horn antenna, two-port cavity integrally formed with the horn antenna and having one port communicated with a throat portion of the horn antenna, one-port cavity integrally formed with the two-port cavity and communicated with the other port of the two-port cavity, a mixer diode located at the throat portion of the horn antenna, a first local oscillator arranged within the two-port cavity, and a second local oscillator arranged within the one-port cavity.

Abstract: A microwave detector arranged in such a manner that a horn antenna element is fastened to the surface of a microstrip plate having a ground plate on its reverse side. The horn antenna element and the ground plate constitute a microwave receiving antenna so that the height of the microstrip plate is lowered. As a result, a compact microwave detector can be constituted.

Abstract: A multi-band microwave detector is designed for detecting microwaves of a plurality of target bands from a specific source and a reference band, which target band includes a specific target band.