Phase shift controlled broadcast switching system

摘要

A broadcast switching system includes at least two sources, such as power amplifiers or transmitters; a waste or dummy load; and an antenna. A non-contacting switching arrangement for such a system includes directional or hybrid couplers for suitably cross-coupling portions of the signals from each of the sources. The present system is such that at least two couplers of nominally identical value may be employed regardless of input power ratios and yet, required power levels can be obtained at the outputs by reason of the deployment of phase shifters providing controlled phase delays over the entire range, which phase delays are precisely selectable for a full range of input power ratios. Although a nominal coupling value of -3 dB for the couplers may be utilized, the invention is not necessarily restricted to this value.