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Developments of ultra wideband phased array antenna transceivers

This paper summarizes and compares two ultra wideband phased array antenna transceivers developed by the authors. The first system has four communication channels operating from 10 to 21 GHz and consists of a phased array of stripline-feed Vivaldi antennas and four wideband transmit/receive modules (T/R modules). The second has one T/R module, a phased array of antipodal Vivaldi antennas, and much wider operation bandwidth of 10 to 35 GHz with six communication channels. Among many types of wideband antennas, the Vivalid antenna is chosen as an antenna element of the array, because of its relatively high gain for a given cross section. Both transceivers use multiline microstrip configuration controlled by a piezoelectric transducer (PET) as a phase shifting device. The up-down movement of a perturber attached at the end of PET causes the variation of the effective dielectric constant of the multiline, which in turn creates a progressive phase shift due to the triangular shape of the perturber