Ultra Long Compact Polymer-Based Waveguide Circuits for Multi-link Optical True-Time-Delay Lines Using WDM Technique

Photonic phased array antenna (PPA) represents one of the most critical technologies for both ballistic missile defense and civilian wireless communications. In this program, Radiant Research, Inc. (RRI) proposes a novel high packaging density true-time-delay (TTD) module for a wideband phased array antenna up to 100 GHz. The proposed photolithographically defined ultra-low-loss polymeric waveguides provide us the only solution for achieving ultra long delay time over tens of nsec with ultra fine resolution of less than 1 ps. Such a monolithic integrated module not only reduces the cost associated with optoelectronic packaging, but also reduces the system payload with an improved reliability. The two-dimensionally distributed polymer waveguide holograms tap the optically-encoded microwave signal with an appropriate delay time equal to the time of flight along the waveguide. Multiple simultaneous communication links can be simply provided by employing multiple directly modulated laser diodes in the same waveguide delay line based on wavelength-division-multiplexing (WDM) technique. The proposed TTD module is expected to have an significantly improved performance at a reduced cost, weight, payload and power consumption in a compact integrated structure, which is highly desired for airborne and space-borne applications. All these unique features will be demonstrated by the end of Phase I.