Broadband frequency divider in waveguide

A microwave frequency divider, comprising

• an input rectangular waveguide including parallel broad-walls and parallel side-walls, said input waveguide being so-dimensioned as to propagate a band of input frequencies through an input port;
• an elongated slot substantially centered in one of said broad-walls, said slot substantially extending in parallel with a normal propagation direction of an input TE.sub.10 mode wave;
• a pair of nonlinear capacitive reactance elements symmetrically and operatively set one on each long side of said slot so as to form therewith a resonance loop at subharmonic frequencies of about half the microwave frequencies of said input band, said reactance elements being oriented in a like polarity direction;
• an elongated conductive bridge element interconnecting corresponding terminals of said pair of non-linear capacitive reactance elements, said bridge element being mounted orthogonally with respect to said normal propagation direction;
• a conductive post substantially connected to the center of said conductive bridge element and extending through the other of said broad-walls;
• means for preventing leakage of substantial microwave energy between said post and said other broad-wall and for applying a DC bias voltage across said pair of nonlinear capacitive reactance elements;
• an adjustable short circuit element provided at an extremity opposite to said input port of said input waveguide;
• an output rectangular waveguide including parallel broad-walls and parallel side-walls, said output waveguide being so-dimensioned as to propagate a band of said subharmonic frequencies and so-disposed about said input waveguide and said slot as to define an output wave propagation direction substantially perpendicular to the propagation direction of the input wave, said elongated slot being substantially centered in the cross-sectional area of said output waveguide.

A microwave frequency divider, comprising

• a primary reduced-height rectangular waveguide, having first and second elongated wall members and two reduced-height side-wall members, dimensioned to propagate a first band of input microwave frequencies and having an elongated slot substantially centered in said first elongated wall member, said slot extending in parallel with a normal TE.sub.10 mode propagation direction thereof;
• an asymmetrical homogeneous waveguide input transformer, consisting of a plurality of waveguide sections having successively graduated side-wall dimensions, being proportioned to effect an electrical match over said band of input frequencies, between said primary reduced-height waveguide and a full-height input waveguide;
• a pair of nonlinear capacitive reactance elements symmetrically set one on each side of said slot, a first electrode of each of said elements being electrically connected to said first elongated wall member, a second electrode of each of said elements being electrically connected directly to said second elongated wall member, the spacing between said elongated wall members being substantially equal to the height of said nonlinear capacitive reactance elements, said reactance elements forming with said slot a resonant loop tuned at subharmonic frequencies of about half said input frequencies;
• a reduced-height adjustable short circuit located at one end of said primary reduced-height waveguide;
• a secondary reduced-height rectangular waveguide having two elongated wall members and two reduced-height side-wall members, dimensioned to propagate a second band of output frequencies corresponding to said subharmonic frequencies in a propagation direction substantially orthogonal to said normal propagation direction of said primary waveguide, the elongated cross-sectional dimension thereof being parallel with said normal propagation direction of said primay waveguide, the junction thereof with said primary waveguide being substantially centered on said elongated slot;
• and
• a symmetrical waveguide output transformer, consisting of a plurality of waveguide sections having successively graduated side-wall dimensions, being proportioned to effect an electrical match over said band of output frequencies, between said secondary reduced-height waveguide and a full-height output waveguide.