Low cost Diplexer for High performance phased array antenna

ABSTRACT: High performance, low cost diplexers in compact form factors are a crucial element in the Geodesic Dome Phase Array Antenna (GDPAA), now at TRL6. One diplexer for SGLS transmit/receive and one for USB transmit/receive are used in each Transmit/Receive module. The current coaxial ceramic diplexers are a major cost and size driver with an impact on the physical configuration of the GDPAA. In quantity the proposed Bulk Acoustic Wave (BAW) diplexers would be about 6 times less expensive and have a volume and weight of about 1/50 that of the coaxial ceramic diplexers. BAW filters have grown from research to recent commercialization in millions of units in the PCS market. The commercial frequencies do not align with the GDPAA, however, and COTS solutions are not available. We propose designing BAW filters and combining circuits for the specific GDPAA bands and rejection needs with a process that can be replicated for other challenges in the increasingly crowded 1-10 GHz spectrum. BENEFIT: The frequencies associated with the GDPAA fall within the total spectrum of cell phone technology. In fact the fabrication of the Transmit/Receive Module developed to TRL6 was dependent on the active components that were associated with this sector of frequency spectrum. Since the spectrum is getting very crowded, bandpass filters using BAW technology will find direct use in some of the current phone systems, especially where high dynamic range, low distortion and high rejections are required. The proposed process of designing BAW filters for transmission and for interference rejection can be replicated for commercial applications as well as military applications