1. A method, comprising: receiving radar pulses from an unknown radar emitter at an input of a radar warning system; processing the received pulses using a weighted finite state machine implemented in the radar warning system to learn a model of the unknown radar emitter; storing the learned model in memory on the radar warning system; estimating, using a computer processor on the radar warning system, a state/function of the unknown radar emitter based on the received radar pulses using the stored learned model; and automatically building finite state machines using finite state transducers based on instructions stored in the memory.