Patent ID: 6744402
Filing Date: 2004-06-01
Classification: H03B

Abstract:
A millimeter-wave transmitting/receiving apparatus comprising:parallel plate conductors disposed at an interval equal to or less than one half of wavelength of a transmission millimeter-wave signal; and the following parts disposed between the parallel plate conductors: (a) a high-frequency diode oscillator for outputting millimeter-wave signals, including: a metal member on which a high-frequency diode for oscillating high-frequency signals, a choke-type bias supply strip for supplying a bias voltage to the high-frequency diode, the choke-type bias supply strip comprising wide strips and narrow strips which are alternately arranged, and a strip conductor for linearly connecting the choke-type bias supply strip and the high-frequency diode are disposed, and a dielectric strip disposed in a vicinity of the high-frequency diode, for receiving and propagating the millimeter-wave signals, lengths of the wide strips and narrow strips of the choke-type bias supply strip being set to approximately &lgr;/4 (&lgr; represents a wavelength of a high-frequency signal), respectively, a length of the strip conductor being set to approximately {(Â¾)+}&lgr; (n represents an integer of 0 or more); (b) a first dielectric strip having one end where the high-frequency diode is disposed, for propagating a millimeter-wave signal outputted from the high-frequency diode oscillator; (c) a variable capacitance diode disposed so that a bias voltage applying direction coincides with an electric field direction of the millimeter-wave signal, for periodically controlling a bias voltage and thereby outputting the millimeter-wave signal as a frequency-modulated transmission millimeter-wave signal; (d) a second dielectric strip having one end which is disposed in proximity to or joined to a portion of the first dielectric strip on a downstream side from the variable capacitance diode in a transmitting direction of the transmission millimeter-wave signal, so as to be electromagnetically coupled with the portion; (e) a circulator having an input end, an input/output end and an output end, the other end of the first dielectric strip being coupled with the input end, a transmission millimeter-wave signal inputted to the input end being outputted to the input/output end, a reception signal inputted to the input/output end being outputted to the output end; (f) a third dielectric strip having one end which is coupled to the input/output end of the circulator, and another end where a transmission/reception antenna is disposed; (g) a fourth dielectric strip having one end which is coupled with the output end of the circulator; and (h) a mixer for mixing signals transmitted to the second and fourth dielectric strips, and generating intermediate-frequency signals by disposing in proximity to each other or joining a mid-portion of the second dielectric strip and a mid-portion of the fourth dielectric strip so as to be electromagnetically coupled to each other.