Low cost system and method for making dual band GPS measurements

A System and Method wherein

• a continuously tracking C/A code carrier phase tracking GPS component is coherently coupled to a L1 and L2 band sampling component and digital signal processing component,
• where said sampling component generates L1 and L2 quadrature samples of the GPS signal,
• where a selection of data over a specified interval is collected for processing,
• where tracking parameters from the C/A code and carrier tracking over said specified interval are used to synthesize feedforward P code and carrier sequences for each of the L1 and L2 channels,
• where said L1 feedforward P code and carrier sequence is mixed with said quadrature L1 samples and filtered to form a baseband, intermediate, quasi-static sequence,
• where said baseband, intermediate, quasi-static sequence from L1 is mixed with the samples from said L2 channel and filtered to form a baseband quasi-static output whose phase is a measurement of the difference between said L1 and L2 quadrature components of the GPS signal.

A System and Method wherein

• a continuously tracking C/A code carrier phase tracking GPS component is coherently coupled to a L1 and L2 band sampling component and digital signal processing component,
• where said sampling component generates L1 and L2 quadrature samples of the GPS signal,
• where a selection of data over a specified interval is collected for processing,
• where tracking parameters from the C/A code and carrier tracking over said specified interval are used to synthesize feedforward P code and carrier sequences for each of the L1 and L2 channels,
• where said L1 and L2 feedforward P code and carrier sequences are mixed with said quadrature L1 and L2 samples, respectively, and filtered to form baseband, intermediate, quasi-static signals,
• where said baseband, intermediate, quasi-static signals are mixed together and filtered to form a baseband quasi-static output whose phase is a measurement of the difference between said L1 and L2 quadrature components of the GPS signal.

A System and Method wherein

• a continuously tracking C/A code carrier phase tracking GPS component is coherently coupled to a L2 band sampling component and digital signal processing component,
• where said sampling component generates L2 quadrature samples of the GPS signal,
• where a selection of data over a specified interval is collected for processing,
• where tracking parameters from the C/A code and carrier tracking over said specified interval are used to synthesize feedforward C/A code and carrier sequences for the L2 channel to form a baseband, intermediate quasi-static sequence,
• where said baseband, intermediate, quasi-static sequence from said L2 channel is filtered to form a baseband quasi-static output whose phase is a measurement of the difference between said L1 and L2 quadrature components of the GPS signal.

A Process wherein

• C/A code carrier phase tracking parameters and L1 and L2 quadrature samples of the GPS signal are provided to a digital signal processor over a specified interval,
• where tracking parameters from the C/A code and carrier tracking over said specified interval are used to synthesize feedforward P code and carrier sequences for each of the L1 and L2 channels,
• where said L1 feedforward P code and carrier sequence is mixed with said quadrature L1 samples and filtered to form a baseband, intermediate, quasi-static sequence,
• where said baseband, intermediate, quasi-static sequence from L1 is mixed with the samples from said L2 channel and filtered to form a baseband quasi-static output whose phase is a measurement of the difference between said L1 and L2 quadrature components of the GPS signal.

A System and Process wherein

• a C/A code carrier phase tracking GPS component is coherently coupled to a L1 and L2 band sampling component and an FPGA,
• where said sampling component generates L1 and L2 quadrature samples of the GPS signal,
• where said FPGA is coupled to a RAM,
• where said RAM collects a selection of L1 and L2 samples over a specified interval,
• where said FPGA uses tracking parameters from the C/A code and carrier tracking over said specified interval are used to synthesize feedforward P code and carrier sequences for each of the L1 and L2 channels,
• where said L1 feedforward P code and carrier sequence is mixed with said quadrature L1 samples and filtered to form a baseband, intermediate, quasi-static sequence,
• where said baseband, intermediate, quasi-static sequence from L1 is mixed with the samples from said L2 channel and filtered to form a baseband quasi-static output whose phase is a measurement of the difference between said L1 and L2 quadrature components of the GPS signal.