Direct Digital Synthesizer for JTRS-compliant Communication Systems

HYPRES is pleased to propose the development of an ultra-low spur, high-bandwidth, low-power direct digital synthesizer (DDS). The proposed fully digital DDS will directly synthesize RF signals with spectrally-pure center frequencies up to 2 GHz andmodulate them with instantaneous bandwidth exceeding 200 MHz with various modulations including FSK, PSK, QPSK, linear FM. The DDS will be compatible with an open-system architecture to ensure seamless integration into conventional electronics environmentusing a modular superconductor/semiconductor interface. We will analyze and optimize two possible DAC architectures based on segmented and sigma-delta approaches. Both of these approaches utilize unique features of ultra-fast, ultra-low power, andfundamentally-linear superconductive single flux quantum technology. Our designs will take advantage of already developed low-speed, quantum-accurate DAC for metrology applications. In this project, we will extend operation to a GHz-range while preservingexcellent linearity and noise performance. In Phase I program, we will perform the design, feasibility analysis, and parameter optimization for high-linearity DAC technology to ensure meeting the 2-2000 MHz objective with at least 16 effective bits and 100dBc spurious free dynamic range over 200 MHz instantaneous bandwidth. In Phase II, we will build the DAC, and then assemble and evaluate a complete DDS system. This project will lead to the development of ultra-high performance direct digital synthesizersenabling Joint Tactical Radio System (JTRS) communication, advanced radar systems, any communication systems for Homeland Security as well as commercial wireless communication systems.