A MILLIMETER-WAVE ULTRA-WIDEBAND FOUR-WAY SWITCH FILTER MODULE BASED ON NOVEL THREE-LINE MICROSTRIP STRUCTURE BAND-PASS FILTERS

This paper presents a millimeter-wave ultra-wideband four-way switch fllter module integrating six building blocks including four band-pass fllters and two switches. The switch fllter module works at whole Ka-band (26{40GHz) and consists of four wideband band- pass fllters and two monolithic microwave integrated circuit (MMIC) single pole four throw (SP4T) switches. The four wideband band-pass fllters are realized by a novel three-line microstrip structure band-pass fllter. Compared with the traditional three-line fllter, the proposed three-line fllter not only retains virtues of traditional three-line fllter, but also resolves drawbacks of it, which include discontinuities between adjacent sections, many parameters of design, and no efiective matching circuits at input/output ports. The proposed three-line fllter is validated by electromagnetic simulation. The developed switch fllter module is fabricated using hybrid integrated technology, which has a size of 64mm£44mm£7.5mm. The fabricated switch fllter module exhibits good performances: for four difierent states, the measured insertion loss and return loss are all better than 8.5dB and 10dB in each pass-band, respectively.