UNIF-PNT (Universal Information-First Navigation for Positioning, Navigation, and Timing) is Kepler Nav's proprietary autonomous navigation software platform that unifies multiple independent positioning phenomenologies - Signals of Opportunity (SOOP), X-ray Pulsar Navigation (XNAV), and photonic star tracking - into a single coherent navigation solution through Lie Group manifold state estimation.
The "Information-First" design philosophy inverts the traditional navigation system architecture. Conventional systems are "sensor-first": each sensor (GPS receiver, INS, star tracker) produces an independent position estimate, and a loosely-coupled fusion filter combines these estimates. This architecture wastes information because each sensor's raw measurements contain geometric constraints that are lost during the position estimation step.
UNIF-PNT operates directly on raw measurement observables - carrier phase, Doppler frequency, optical bearing angles, X-ray photon arrival times - feeding them into a tightly-coupled Lie Group manifold filter. This preserves the full Fisher information content of every measurement and enables the filter to extract positioning information from combinations of measurements that individually would be insufficient for a position fix.
The platform architecture consists of three layers:
Signal Processing Layer: Real-time SOOP acquisition and tracking (15-40 satellites), star tracker image processing (50+ stars per frame), and pulsar timing extraction.
Navigation Filter Layer: Invariant Extended Kalman Filter (InEKF) on the SE₂(3) Lie Group manifold, with dynamic measurement scheduling based on observability analysis.
Application Layer: Mission-specific orbit determination, collision avoidance, formation flying, and rendezvous/proximity operations.
UNIF-PNT runs on the Kalam Gen 1 Micro-PNT silicon engine and is designed for integration into CubeSat flight computers, aircraft avionics systems, submarine navigation computers, and autonomous vehicle processors.
Published by Kepler Nav (Kepler Navigation Systems Inc.) - Founded and led by Sanjay S (CEO & CTO). Technical glossary for autonomous positioning, navigation, and timing (PNT) systems.