Abstract In a distributed IMPATT structure, power is coupled out through a side contact. That is, in previously proposed distributed IMPATT structures, the gain medium (the active region of the IMPATT) operates as a transmission line. The prior art has attempted to couple output power from the gain medium through an end contact, i.e., through a contact which is perpendicular to the primary direction of energy propagation (and also to the direction of maximum elongation) of the active medium. In the present invention, a sidewall contact extends in a direction which is parallel to the principal direction of propagation of the energy in the active medium. Thus, the sidewall contact plus the active region together can be considered as a single transmission line. This extended transmission line is also connected to a second distributed semiconductor element which functions as a varactor. By changing the bias voltage on this varactor, the distributed capacitance of a transmission line is changed, and this change in transmission line loading causes a change in the propagation characteristic of the transmission line.
A voltage-controlled oscillator comprising: (a) a semiconductor diode active region interposed between frontside and backside contacts, said semiconductor active region defining a negative resistance diode between said frontside and backside contacts; (b) said semiconductor active region and said frontside and backside contacts being elongated in a first direction; (c) said frontside contact being extended beyond said active region in a direction normal to said first direction to form a transmission line having a principal direction of propagation substantially parallel to said first direction; and (d) a separate variable-capacitance element coupled to said frontside contact for controlling the propagation characteristic of said transmission line.
Claim 2
Dependent Claim
103 words
A voltage-controlled oscillator comprising: (a) a semiconductor diode active region interposed between frontside and backside contacts, said semiconductor active region defining a negative resistance diode between said frontside and backside contacts; (b) said semiconductor active region and said frontside and backside contacts being elongated in a first direction; (c) said frontside contact being extended beyond said active region in a direction normal to said first direction to form a transmission line having a principal direction of propagation substantially parallel to said first direction; and (d) a separate variable-capacitance element coupled to said frontside contact for controlling the propagation characteristic of said transmission line.
Claim 3
Dependent Claim
33 words
The oscillator of claim 1, wherein said frontside contact is capacitatively coupled to a microstrip line, said microstrip line extending beyond said active region in a direction substantially parallel to said first direction.
Claim 4
Dependent Claim
14 words
The oscillator of claim 1, wherein said negative resistance diode is an IMPATT diode.
Claim 5
Dependent Claim
14 words
The oscillator of claim 3, wherein said IMPATT diode is a double-drift IMPATT diode.
Claim 6
Dependent Claim
13 words
The oscillator of claim 2, wherein said microstrip is impedance-matched to said diode.
Claim 7
Dependent Claim
37 words
The oscillator of claim 5, wherein said microstrip line is impedance-matched to a plurality of said active diode regions, each said active diode region being defined by a width dimension, each said width having a unique dimension.