The proposed photonic antenna coupled MWIR photodetector technology enables ultra-compact high performance MWIR sensing with high quantum efficiency. This technology avoids the bulky and heavy cryogenic cooling system and enables ultra-compact carbon-based trace gases (CH4, CO2, and CO) sensing with substantially reduced device size, weight and power consumption and improved system reliability for small satellite applications. It forms a key building block in IR cameras for numerous NASA's earth remote applications, including space telescope and high-sensitive space object imaging, high definition acquisition of radiation characteristics of Earth and its environments, monitoring of atmospheric variables such as temperature, winds, and trace constituents for understanding and predicting the earth's climate and potential hazards as well as topographical profiling of Earth for mineral identification and vegetation mapping. The high-performance ultra-compact MWIR detector technology is particularly useful in detecting ultra-weak signals for many critical military and homeland security applications such as night vision, missile early launch detection and remote chemical sensing and detection for biological/chemical warfare. Commercial markets include leak detection, chemical process control, remote chemical sensing for atmospheric pollution and drug monitoring, IR spectroscopy, and medical diagnoses. The technology developed herein should considerably accelerate the commercialization of IR camera technologies to meet the potential needs of the huge defense and commercial market.