%0 Journal Article %1 Miller2000 %A Miller, M. M. %A Corbell, P. M. %A Raquet, J. F. %D 2000 %J Proc. of the ION GPS Conf. %K softwareRadio, softwareReceiver %P 2362-2371 %T Design and Validation of Digitized Intermediate Frequency GPS Signal and Receiver Software Models for Developing and Comparing Advanced GPS Receiver Technologies %X Recent developments in advanced GPS receiver designs require lower-level observables than what are currently modeled by most commercial GPS software simulation packages. Kalman filtering based joint signal tracking algorithms, a subset of Direct Correlator Output Processing (DCOP) technologies, promise more robust tracking performance by jointly processing the demodulated I and Q signal components of each signal, thereby exploiting the geometrical correlations of the tracking loop errors and platform dynamics. Ultra-tightly integrated GPS/INS systems also require these I and Q signal components, which are scarcely available in today's commercial GPS simulation software packages. Of those commercial packages that do generate these measurements, few, if any, are driven by a receiver trajectory, satellite ephemeris, and other environmental parameters. All the models discussed in this paper are driven by the above mentioned truth environment. This is important for integration into inertial measurement simulators when evaluating GPS/INS coupled systems. A high-fidelity approach to generating these I and Q measurements was accomplished by designing a GPS signal generator at the output of the analog-to-digital (A/D) converter and a realistic GPS DSP Receiver model to process the GPS signal generator output. A faster analytical method was developed that generates the same I and Q measurements through a mathematical model of the tracking process. Each I and Q simulator (fed by the same trajectory, satellite position, and other environmental parameters) generated independent I and Q signal components which were compared for a first-level validity check. The analytical I and Q model followed the higher resolution truth model very well, especially at low dynamics and over short time periods. At higher dynamics, the increased fidelity of the signal and receiver simulators become apparent, and the I and Q analytical approximations exhibited less accuracy. Both the high fidelity and the analytical models provide the ability to design and test new signal tracking architectures, with access to the demodulated but unprocessed I and Q signal components. The analytical I and Q model operates as a self-contained I and Q signal generator, driven by the same truth environment components used to simulate an INS. It provides the typically unavailable I and Q signal components of a GPS signal, and has been used in the modeling and simulation of ultra-tightly integrated GPS/INS systems.

@article{Miller2000, abstract = {Recent developments in advanced GPS receiver designs require lower-level observables than what are currently modeled by most commercial GPS software simulation packages. Kalman filtering based joint signal tracking algorithms, a subset of Direct Correlator Output Processing (DCOP) technologies, promise more robust tracking performance by jointly processing the demodulated I and Q signal components of each signal, thereby exploiting the geometrical correlations of the tracking loop errors and platform dynamics. Ultra-tightly integrated GPS/INS systems also require these I and Q signal components, which are scarcely available in today's commercial GPS simulation software packages. Of those commercial packages that do generate these measurements, few, if any, are driven by a receiver trajectory, satellite ephemeris, and other environmental parameters. All the models discussed in this paper are driven by the above mentioned truth environment. This is important for integration into inertial measurement simulators when evaluating GPS/INS coupled systems. A high-fidelity approach to generating these I and Q measurements was accomplished by designing a GPS signal generator at the output of the analog-to-digital (A/D) converter and a realistic GPS DSP Receiver model to process the GPS signal generator output. A faster analytical method was developed that generates the same I and Q measurements through a mathematical model of the tracking process. Each I and Q simulator (fed by the same trajectory, satellite position, and other environmental parameters) generated independent I and Q signal components which were compared for a first-level validity check. The analytical I and Q model followed the higher resolution truth model very well, especially at low dynamics and over short time periods. At higher dynamics, the increased fidelity of the signal and receiver simulators become apparent, and the I and Q analytical approximations exhibited less accuracy. Both the high fidelity and the analytical models provide the ability to design and test new signal tracking architectures, with access to the demodulated but unprocessed I and Q signal components. The analytical I and Q model operates as a self-contained I and Q signal generator, driven by the same truth environment components used to simulate an INS. It provides the typically unavailable I and Q signal components of a GPS signal, and has been used in the modeling and simulation of ultra-tightly integrated GPS/INS systems.}, added-at = {2011-05-30T10:41:10.000+0200}, author = {Miller, M. M. and Corbell, P. M. and Raquet, J. F.}, biburl = {https://www.bibsonomy.org/bibtex/2024c371521609ff362beb3933f49c0c0/bmuth}, groups = {private}, interhash = {60b2e6ff7efee73ae57c8db5645ef9cd}, intrahash = {024c371521609ff362beb3933f49c0c0}, journal = {Proc. of the ION GPS Conf.}, keywords = {softwareRadio, softwareReceiver}, owner = {bmuth}, pages = {2362-2371}, timestamp = {2014-08-11T22:37:44.000+0200}, title = {{Design and Validation of Digitized Intermediate Frequency GPS Signal and Receiver Software Models for Developing and Comparing Advanced GPS Receiver Technologies}}, username = {bmuth}, year = 2000 }