Middle-wave infrared (MWIR, 3-5 ¿¿m) photodetectors are of great importance in numerous NASA applications, including thermal remote sensing for carbon-based trace gases (CH4, CO2, and CO), heat capacity mapping for earth resource locating, environment and atmosphere monitoring, and IR spectroscopy. However, existing MWIR photodetectors are require a low operating temperature, below 77K to achieve high photodetectivity (D*). The requirement for cryogenic cooling systems adds cost, weight and reliability issues, thereby making it unsuitable for small satellite applications. This STTR project aims to develop a new photonic antenna coupled MWIR photodetector with a significantly enhanced quantum efficiency. In addition, the antenna technology would also allow a large-area signal collection with a small active area of the detector. Successfully developing the proposed innovation is expected to provide an enabling technology for ultra-compact high performance MWIR detection and imaging systems suitable for NASA's small satellite earth remote sensing applications. In phase I, the proposed photonic antenna enhanced MWIR photodetector technology will be evaluated and compared with existing technologies. The proposed photonic antenna structure will be simulated to generate an optimal design. A preliminary photonic antenna coupled MWIR photodetector will be developed for proof-of-concept demonstration. In Phase II, a prototype of the photonic antenna coupled MWIR photodetector will be developed and packaged with supporting electronics and software interfaces for laboratory demonstration.