New Differential Phase Shift Networks Combining All-Pass and Band-Pass Elements

Networks capable of producing differential phase shifts of any value up to 180/spl deg/ with bandwidths as large as 3:1 have been investigated by using computer optimization techniques. A new class of networks that combine band-pass (lines and stubs in ladder form) and all-pass (C-sections) has evolved with performance comparable to that of the cascaded C-section networks described by Schiffman and others. In most cases the new networks are more easily realized, more easily adjusted or tuned, and require less reference-line length.