A Frequency Triplexer for Ultra-Wideband Systems Utilizing Combined Broadside- and Edge-Coupled Filters

A fully integrated triplexer for multiband ultra-wideband radio is presented. The triplexer utilizes a microstrip network and three combined broadside- and edge-coupled filters. It is fully integrated in a printed circuit board with low requirements on the printed circuit board process tolerance. Three flat subbands in the frequency band 3.1-4.8 GHz have been achieved. The group delay variation within each 500-MHz subband was measured to be around 1 ns. A good agreement between simulation and measurement was obtained.