Patent GB-1319096-A (GB)
Title: High frequency coupling arrangements
IPC: H01P5/04
Filed: 1970-11-18
Abstract: 1319096 Hybrid couplers THOMSON CSF 18 Nov 1970 [20 Nov 1969] 54844/70 Heading H1W [Also in Division H4] An arrangement for coupling two or more R.F. power sources to one or more common utilization circuits comprises a hybrid coupler for each source, two cavity couplers each having as many inputs as there are sources, and a single output, a terminating load for each hybrid coupler, and connection means fed by the cavity couplers and supplying the utilization circuits. As described, two transmitters 1, 2, Fig. 2, are respectively connected to first ports 11, 21 of two hybrid couplers 10, 20. Said couplers may be 3 dB. directional couplers, or one and a half wavelengths ring couplers. In the first type there is a phase difference of #/2, and in the second type a phase difference of #, between the output port signals. Like phased third ports 13, 23 of the hybrid couplers 10, 20 are respectively connected to inputs 101, 102 of a first cavity coupler 100, and like phased fourth ports 14, 24 are similarly connected to inputs 201, 202 of a second cavity coupler 200. Second ports 12, 22 are terminated by matched loads 15, 25. The cavity couplers may be of the kind described in Specification 1,022,553, each comprising a cylindrical cavity with two transverse end walls. A central conductor extends from a coaxial cable at one end wall to the other end wall, where it is terminated. An appropriate number of rotatable coupling loops having their axes parallel to the central conductor are disposed around it. Each loop extends from a coaxial cable at the end wall where the central conductor is terminated, and is itself connected to the other end wall (Fig. 1, not shown). The output 105 of the cavity coupler 100 is connected through a phase shifter 5, which provides compensation for the phase shifts introduced by the hybrid couplers 10, 20, to a first input of a T-coupler 8. The output 205 of the cavity coupler 200 is directly connected to the second input of the T-coupler 8, output from which is taken to an aerial 6. Instead of the phaseshifter 5 and T-coupler 8, a hybrid coupler 50, Fig. 3, may be used which is similar to the hybrid couplers 10, 20, and which brings the two outputs from the cavity couplers 100, 200 into phase. In a second embodiment, four transmitters are associated with four hybrid couplers, which supply two cavity couplers each having four inputs (Fig. 4, not shown). In a third embodiment, in which two aerials are fed from a number of transmitters, the outputs of the two cavity couplers are respectively connected to the central conductors of two cavity distributers, which are two-loop cavity couplers used in reverse. First outputs of each distributer are connected to input ports of a first hybrid coupler, the other ports of which are respectively connected to a first aerial and to a matched terminating load. Second outputs of each distributer are similarly connected through a second hybrid coupler to feed a second aerial (Fig. 5, not shown). In a third embodiment, in which two transmitters are coupled, sampling means are inserted between the transmitters and the hybrid couplers, and supply a control circuit. Equivalent coupling loops of the cavity couplers are mechanically linked and are rotatable by electric motor means connected to the control circuit. This enables adjustments to be made automatically should, for example, one transmitter fail.