Patent ID: 8300813
Filing Date: 2012-10-30
Classification: G01S

Abstract:
1. A method executed by a first unit having a first antenna located at a first location, which antenna is constructed to receive a signal comprising a sum of constituent signal, each from a different source of a plurality of sources, and each of the constituent signals containing a component that is modulated by a known code and a component that is modulated by a code that is not publicly known and not known to said method (secret code), for communicating a data signal of said first unit to a second unit having a second antenna at a second location that is known to said method, which is associated with a second unit, comprising the steps of: processing said signal to remove a Doppler frequency shift that said signal experiences in arriving at said first antenna, thereby creating a signal A; processing signal A with said data signal expressed through time delay, frequency shift, or both, to form signal A′ creating a signal B that corresponds to a signal that is expected to have been received at said second antenna in response to a signal transmitted by a particular one of said sources, and processing said signal B with said data signal expressed through time delay, frequency shift, or both, to form signal B′; creating a signal C that is a function of signal A′ multiplied by signal B′; and sending signal C to said second unit.