AeroMancer Technologies proposes to develop a Dome Lidar system for hemispherical early warning detection and tracking of threats using a compact, eye-safe infrared active electro-optic sensor. Current early warning detection systems are radar-based and are too large to be deployed on the same platform where laser-based countermeasures are installed. Our proposed method for achieving hemispherical coverage is by using a narrow field-of-view multi-aperture lidar beam that is scanned along two axis to attain full coverage at the requested track rate of 10 Hz. In Phase I, we will analyze the measurement requirements in detail and translate them into the functional requirements of a compact sensor that can meet the SWaP requirements to be installed on a deployed platform. We will develop a lidar performance simulation tool using a numerical model of the lidar and use it to perform trade studies. Using the requirements analysis and performance simulations, we will develop a conceptual design of the proposed system. We will develop the preliminary design of a detection and tracking algorithm to extract position and velocity of the incoming target from lidar data.