Method of enhancing signal tracking in global positioning system receivers

A global positioning system receiver having enhanced signal tracking after signal acquisition, the global positioning system receiver comprising:

• signal separation circuitry configured to separate an acquired continuous time global positioning signal into in-phase and quadrature signals I and Q;
• signal processing circuitry coupled to the signal separation circuitry and configured to sample the signals I and Q over a predetection interval (PDI) to provide discrete time signals and to generate from the discrete time signals a component in-phase measurement and a component quadrature measurement for each of a plurality of PDI segments of one PDI;
• tracking circuitry coupled to the signal processing circuitry and configured to generate, for each of a plurality of different frequency bins and for a time corresponding to the PDI, a composite in-phase measurement and a composite quadrature measurement by combining component in-phase measurements and component quadrature measurements from the PDI;
• and
• power detecting circuitry configured to detect power in each of the plurality of different frequency bins for the PDI using the corresponding composite in-phase measurement and the corresponding composite quadrature measurement generated for the frequency bin, wherein the power detection circuitry is configured to determine which one of the plurality of different frequency bins contains the highest detected power.

A method of enhancing signal tracking in a global positioning system receiver utilizing a multiple segment multiple frequency banked filter, the method comprising:

• acquiring a continuous time global positioning signal;
• separating the continuous time global positioning signal into in-phase and quadrature signals I and Q;
• sampling the signals I and Q over a predetection interval (PDI) to provide discrete time signals;
• generating from the discrete time signals a component in-phase measurement and a component quadrature measurement for each of a plurality of PDI segments of one PDI;
• for each of a plurality of different frequency bins, generating a composite in-phase measurement by combining component in-phase measurements and component quadrature measurements from the PDI, and generating a composite quadrature measurement by combining component in-phase measurements and component quadrature measurements from the PDI;
• generating for the PDI prompt versions of a composite in-phase measurement Xp(0) and a quadrature in-phase measurement Yp(0) corresponding to a frequency bin having an estimated carrier frequency error of approximately zero;
• determining an arctangent of Yp(0)/Xp(0) to obtain a current carrier phase Θ;
• subtracting a delayed version of the carrier phase Θ from the current carrier phase Θ to obtain a value ΔΘ;
• providing a carrier feedback output as a function of the value ΔΘ;
• performing the step of separating the continuous time global positioning signal into the in-phase and quadrature signals I and Q as a function of the carrier feedback output;
• and
• detecting power in each of the plurality of different frequency bins for the PDI using the corresponding composite in-phase measurement and the corresponding composite quadrature measurement generated for the frequency bin.