An Interactive Web-Based Tutor for Enhancing Adult Literacy

Not Available Vector waveform estimation theory implies that a GPS signal processor be constructed as a centralized estimator, in which inter-path statistical information is utilized in extracting state dynamics information from the spread spectrum signals. TISI has developed and implemented such a scheme, known as Integrated Demodulation Navigation (IDN), which addresses robust carrier phase tracking in high Dynamics and blockage. In extending this development to the tactical jamming environment, specific challenges must be surmounted including estimation of signal amplitudes and compensation for deleterious amplitude and phase effects introduced by front-end spatial nulling. In its Phase I effort an enhanced amplitude estimation scheme for IDN will be developed, which will be evaluated in non-linear tracking simulations. TISI's simulator environment will be extended to include antenna pattern and vehicle blockage effects, as well as multiple jammer sources. A simplified model of spatial nulling disturbances will also be introduced. In preparation for RF testing of a prototype receiver in Phase II, MacAulay-Brown will develop a virtual GPS receiver environment concept for capture and playback of actual jammer and spatial pre-filtering scenarios produced by the AWFS. Finally, TISI will identify and compare options for implementing IDN in the GRAM-SAASM framework.