Title :
A planar orthomode transducer
Author :
Jackson, Robert W.
Author_Institution :
Dept. of Electr. & Comput. Eng., Massachusetts Univ., Amherst, MA, USA
Abstract :
The planar orthomode transducer (OMT) described in this paper couples two microstrip inputs to two orthogonal modes in a square waveguide. One microstripline feeds a 180/spl deg/ hybrid that in turn excites two waveguide probes. A second microstrip directly feeds a third waveguide probe. Mode symmetry provides isolation between the two feeds. All circuitry and probes are fabricated on a single substrate to minimize fabrication cost. An experimental prototype has 30 to 40 dB isolation at millimeter wave frequencies. The low cost and small size of this structure make it appropriate for use in commercial communications applications.
Keywords :
S-parameters; circuit simulation; microstrip couplers; microstrip transitions; millimetre wave couplers; mode matching; multiport networks; transceivers; 0.2 to 1 dB; balance output; capacitive coupling; finite element simulator; five-port S parameters; insertion losses; isolation between feeds; low cost; matching circuit; microstrip inputs; millimeter wave frequencies; mode symmetry; orthogonal modes; planar orthomode transducer; rat race coupler; rat race hybrid; single substrate; small size; square waveguide; waveguide probes; waveguide to microstrip transitions; Costs; Coupling circuits; Fabrication; Feeds; Microstrip; Millimeter wave circuits; Planar waveguides; Probes; Prototypes; Transducers;
Journal_Title :
Microwave and Wireless Components Letters, IEEE
DOI :
10.1109/7260.974553
