GNSS long-code acquisition, ambiguity resolution, and signal validation

A method for providing direct acquisition of a spread spectrum RF emission, comprising:

• intercepting, by an interceptor, at least one spread spectrum RF emission within a transmission medium;
• processing, by a spectral compressor, the emission using spectral compression utilizing a non-linear operation to produce at least one of a chipping or a carrier-related observable;
• determining, by a physical state estimator, at least one member of a relative physical state between the interceptor and the at least one emitter based on the observable;
• determining, by the physical state estimator, a domain of code chips for at least one code assigned to the at least one emitter based on the at least one observable;
• and
• cross correlating, by a cross correlator, the spread spectrum sequence with the emission to produce a code phase of the emission where the spread spectrum sequence is configured as a function of the domain of code chips determined for at least one code assigned to the at least one emitter.