1. A method for determining location information of a receiver in a multipath environment, the method comprising the steps of: receiving a signal containing a plurality of location-determining signals associated with a plurality of signal sources, wherein each of said signal sources is associated with a reference signal; correlating said signal with said plurality of reference signal to yield a plurality of correlation functions; generating a signal constraint from each correlation function; transforming said signal constraints into receiver constraints; fusing said receiver constraints to yield a unified receiver constraint; and determining said location information based on said unified receiver constraint.