Radio Communication with Hypersonic Aerial Vehicle

During the successful Phase I program, Systems & Processes Engineering Corporation (SPEC) demonstrated, through modeling, the potential to significantly increase transmission through a hypersonic plasma layer by utilizing a combination of novel approaches.  Current drones use large 24 to 30 inch high gain Ku band antennas, which cannot be used on hypersonic vehicles.  Instead, our proposed baseline antenna design uses a phased array composed of transmit and receive patch elements separated into rows along the outside of the vehicles body.  Plasma electrons are forced into “rivulets” with low electron concentrations along the antenna rows interspersed by rows of high electron/ion concentration.  The DC magnetic field and RF clearing field then form a resonate structure in the plasma, which is maintained along the flow direction length of the antenna. The proposed Phase II technical effort builds upon the comprehensive modeling, analysis and trades studies conducted in Phase I to experimentally demonstrate prototype performance in a high enthalpy hypersonic environment. The Phase II technical objectives are configured to demonstrate, through analysis and prototype fabrication, the S- band ponderomotive electron sweeper, permanent magnet electron stabilizer and phased array satellite communications antenna design. The prototype systems will then be experimentally tested in a relevant Mach 6.6 high-enthalpy environment: single patch first, row second and full phased array third to demonstrate innovative solutions for efficient radio communications with a hypersonic vehicle for both GPS and for a phased array satellite communication antenna array in the 7.25 to 8.4 GHz band. Hypersonic computational fluid dynamics (CFD) simulations of the near-wall boundary layer will be verified over the vehicle surface to support the evaluation of: antenna performance though the plasma layer, transmissivity through the plasma, and S-band Ponderomotive effectiveness in reducing electron density. The prototype antenna design, fabrication, integration, and test will be matured during the proposed Phase II effort. The prototypes will be exhaustively tested in a high enthalpy hypersonic facility wind tunnel at Texas A&M University (TAMU), under the direction of Dr. Tichenor. The Hypervelocity Expansion Tunnel (HXT) housed within the TAMU National Aerothermochemistry and Hypersonics Laboratory (NAL) will produce true Mach 6.6 flight enthalpies, enabling verification of the RF transmissivity through the hypersonic plasma layer. The proposed Phase II Program Plan focuses on the development of the antenna, ponderomotive-based plasma electron sweeper, and rare-earth magnet electron stabilizer assembly. The work plan is a logical, chronological progression, which will result in a verified and demonstrated design and delivery of operational phased array satellite communications system prototypes that can operate through plasma at Mach 6.6.