Demonstration of an all-digital 7-bit 33-channel photonic delay line for phased-array radars
Abbreviated Journal Title
TRUE-TIME-DELAY; ANTENNA; SYSTEM; Optics
A 7-bit multichannel photonic delay line for phased-array antenna control is demonstrated. Multichannel (33-pixel) ferroelectric liquid-crystal (FLC) devices are used as polarization rotation elements, and polarization beam-splitter cubes are used as polarization elements that route the optical signals to different paths. The controller is remotely fed by a unique fiber-optic-array design that uses gradient-index lens collimators for the input single-mode polarization-maintaining fibers. The optical signal is collected by a similar fiber array that uses multimode fibers for improved coupling efficiency. Photonic delay-line (PDL) design issues such as multiport assemblies, multipixel FLC designs, and delay-line architectures are discussed. Furthermore, various PDL parameters are examined. High electrical isolation numbers are obtained for both the within-channel leakage noise (e.g., less than -70 dB) and the interchannel cross talk (e.g., less than -90 dB). Optical and electrical insertion loss is examined for the PDL as well as for the overall system. A high-compression dynamic range of 149 dB . Hz and a spurious free dynamic range of 105 dB . Hz(2/3) are presented. (C) 2000 Optical Society of America. OCIS codes: 280.5110, 160.3710, 060.2300.
"Demonstration of an all-digital 7-bit 33-channel photonic delay line for phased-array radars" (2000). Faculty Bibliography 2000s. 2684.