Experimental study of orthomode couplers for use in power combining and distribution

It is pointed out that the number of practical applications for waveguide power combiners and power distributors is increasing. Such applications are related to communications, radar, electronic countermeasures, satellites, and industrial heating. The present investigation is concerned with the possible use of a variable coupler based upon orthomode couplers connected by a half-wave plate. The theoretical principles of operation for the device are discussed, and an experimental model at 3 GHz is designed and tested. The test results are very encouraging, and useful operation over a bandwidth of 200 MHz is demonstrated. Attention is given to the possibility to improve the match and to realize a bandwidth of 10 percent by increasing the separation of the waveguide ports.