Welkin Sciences proposes to develop a comprehensive capability to formulate, analyze, simulate, prototype, and test scintillation-hardened receiver designs, including those enabled with built-in Matched Channel Filter (MCF) functionality. During Phase I, several MCF design architectures will be analyzed using CommLink, our high-fidelity computer simulation framework. Emulation of the type of down-links used by the Iridium user network will be implemented in the CommLink code. These are of particular interest because they employ differentially-encoded PSK modulation, thereby allowing an MCF to be adapted using blind equalization (without the need for training sequences). MCF-enabled Iridium down-links will be included in the CommLink-aided analyses. The various MCF designs will be compared on the basis of mitigation effectiveness and implementation complexity. We anticipate that many (if not all) of the analytical issues addressed in the solicitation will be resolved during Phase I. The full capability will be developed and delivered at the end of Phase II, including a further upgraded version of the CommLink code supporting simulation-aided analysis of a much wider range of mitigation techniques. Also, a hardware platform called the Scintillation-Hardened Prototype Terminal (SHaPT) will be developed and delivered. Like our CoLTS-AD platform, it will employ several high-speed processor boards interconnected by PCI Express (PCIe) 4.0 interfaces. These processor types will include one or two multi-core central processing units (CPUs), two or three data-center-class general-purpose graphical processing units (GPGPUs), and an RF System-on-Chip (RFSoC) board. SHaPT will support multiple RF input and output signal ports allowing the configuration of prototype terminals employing multiple antennae. Prototypes of communication terminals using Multiple-In/Multiple-Out (MIMO) techniques can be prototyped and tested in a laboratory setting. The RF output signal ports will be compatible with MIL-STD-188-164 so SHaPT can support over-the-air SATCOM testing.