Hybrid Orthomode Transducer for E-Band Point-to-Point Communication Systems

The paper presents a design of a hybrid orthomode transducer (OMT) for E-band point-to-point communication systems. The designed OMT is based on a combination of a waveguide turnstile with a WR12-based distribution system and two planar antiphase power combiners realized on Rogers RO4350B substrate. The common ports of the combiners are connected to an integrated transceiver MMIC forming a compact single-chip E-band front-end. Practically the OMT structure is realized within only two metal parts that facilitates the design and reduces manufacturing cost. An input interface of the OMT is based on a standard circular waveguide that allows integration with different antenna types. Characteristics of the designed OMT were first optimized for operation in the frequency band of 71–76 GHz using full-wave simulations and later confirmed by measurements of the fabricated samples. Measured OMT return loss is better than 10 dB in the wide frequency range 60.5-87 GHz and better than 18 dB in the target 71–76 GHz band. Measured insertion loss is only 1.2 dB that conforms with known mm-wave OMT designs.