This paper presents the Passive Receiver Framework (PRF), a unified theoretical system integrating IMF–GDD physics, its mathematical formulation, receiver-based interstellar interpretation, and the Passive Intelligence Receiver (PIR) model. The framework establishes a causal chain:Exotic Propulsion → IMF–GDD Residue → Signal Interaction → Passive Intelligence (Receiver-Based Systems). This work proposes a shift from emission-based detection to receiver-based intelligence recognition.