Multiwavelength optically controlled phased-array antennas

A novel multiwavelength scheme is proposed and demonstrated for one-dimensional (1-D) and two dimensional (2-D) optically controlled phased-array antenna (OCPAA) systems with true time delay (TTD), This hardware-compressive architecture employs a multiwavelength laser source in conjunction with a programmable dispersion matrix (PDM) and switched optical delay lines (SODL's) to generate all the required time delays for beam steering in 2-D phased-array antenna systems, Independent control of elevation and azimuthal scan is achieved by combining wavelength-dependent and wavelength-independent time delays, An experimental prototype of 4 x 2 array with 2-b x 2-b resolution is constructed to demonstrate the feasibility of the multiwavelength OC:PPA (MWOCPAA). Broadband linear RF phase shift is measured in both elevation and azimuthal planes over the entire bandwidth of the electro-optic (EO) modulator, System issues such as insertion loss, array size, and channel isolation are discussed. Extension of the multiwavelength scheme to a common transmit/receive (T/R) module with TTD is also described.