Receiver for GPS-Like Signals

Abstract

A module for receiving a plurality of signals that are modulated with a common carrier, where each of the signals includes information that enables a determination of a distance from said receiver to a source that transmits the signal, and outputs to outside the module a digital representation of a downshifted replica of the received signals or, alternatively, outputs a stored and delayed version of the downshifted replica of the received signals together with information about the delay.

1 . A method for use by a terrestrial supplicant system in conjunction with a system of earth-orbiting satellites in which each satellite transmits a global positioning systemsignal containing data that is encoded using a first code that is publicly known and that is also encoded using a second code that is not known to said supplicant system, the method comprising the steps of:
 acquiring, for a particular time interval, a received signal in which signals related to the signals transmitted by a plurality of the satellites are commingled;   developing a supplicant signal from the received signal, said supplicant signal being a frequency-shifted version of said received signal that contains said first codes and said second codes for the plurality of satellites; and   outputting said supplicant signal and a time indication of said particular time interval.   
     
     
         2 . The method of  claim 1  further comprising the step of:
 storing said supplicant signal in a memory, wherein said step of outputting obtains said supplicant signal from said memory. 
 
     
     
         3 . The method of  claim 2 , where
 said steps of acquiring, developing, and storing are executed for a plurality of time intervals,   said storing stores a time indication associated with each time interval of said plurality of time intervals; and   said step of outputting outputs one or more of the stored supplicant signals.   
     
     
         4 . The method of  claim 1  where further comprising outputting an assertion of global position of said supplicant system. 
     
     
         5 . The method of  claim 1  where said outputting is adapted to send said supplicant signal outside said supplicant system via a communications network. 
     
     
         6 . Apparatus for use in conjunction with a system of earth-orbiting satellites in which each satellite transmits a global positioning system signal containing data that is encoded using a first code that is publicly known and that is also encoded using a second code that is not known to said apparatus comprising
 receiver for acquiring, for one or more particular time intervals, a received signal in which signals related to the signals transmitted by a plurality of the satellites are commingled;   a processor for developing, from the received signal, a supplicant signal for each of said one or more particular time intervals, each supplicant signal of said one or more supplicant signals being a frequency-shifted version of said received signal that contains said first code and said second code for the plurality of satellites; and   a transmission element for outputting at least one of said one or more supplicant signals together corresponding identifications of the time intervals of the outputted supplicant signals.   
     
     
         7 . The apparatus of  claim 6  where said transmission element is a circuit adapted for communicating via a telecommunications network. 
     
     
         8 . The apparatus of  claim 6  further comprising a memory for storing said one or more supplicant signals. 
     
     
         9 . The apparatus of  claim 6  further comprising a user interface for specifying an assertion of global position of said apparatus. 
     
     
         10 . The apparatus of  claim 6  further comprising an article to which said apparatus is connected. 
     
     
         11 . The apparatus of  claim 10  where said device includes means for facilitating commercial or financial transactions. 
     
     
         12 . The apparatus of  claim 10  where said device is a portable computing device. 
     
     
         13 . The apparatus of  claim 12  where said portable computing device creates a file and employs said transmission element to output said file in association with the outputting of said at least one of said one or more supplicant signals. 
     
     
         14 . The method of  claim 1  further comprising an element for receiving information from a remote supplier subsequent to said outputting by said transmitting element.