A network for combining radio systems at 4, 6 and 11 kmc

Development of the broadband horn reflector antenna has permitted the simultaneous radiation and reception of radio signals on different frequencies in the three common-carrier bands in which the Bell System has developed radio relay systems. A necessary adjunct to the antenna is a network to combine or separate the common carrier bands and also to combine or separate the two polarizations of any one band. The particular form of the network that is described was designed to meet strict system requirements on impedance match, insertion loss and cross-coupling between ports.