Event Title

Electro-Optical Grid Reference System (EOGRS) Receiver Optimization

Location

Hager-Lubbers Exhibition Hall

Start Date

18-4-2017 3:30 PM

Description

PURPOSE: The EOGRS is defined as a relative navigation system. The system allows navigation with respect to the coordinates of a transmitter. The purpose of this project was to explore and implement optimizations to the existing prototype system. The goal of this overall system is to achieve one nautical mile (or ~6000 ft.). PROCEDURES: Examination of key components of the system were completed. Areas for improvement were chosen that had the potential for greatest impact on increasing the systems dynamic range. The chosen areas for optimization were Laser Modulation, Demodulation & Signal Processing, and Interface. Research, analysis, design, verification and demonstrations were then completed in each area. OUTCOME: First, the present modulation scheme was updated to M-PPM (P-2, M=12) to improve the pk to average optical power. Increasing the pk power by 4x would result in 2x distance improvement. M-PPM (P-2, M=12) is shown to increase the pk to average optical power from 2x to 6x while maintaining an acceptable BER and sub grid resolution. Second, the comparator demodulation was replaced with a discrete time signal processor, greatly improving receiver sensitivity, allowing for a dynamic demodulation threshold. This change improved the performance of the tested system from 1000’ to 2500’. Lastly, a new CAN Bus interface was chosen that allowed for a versatile plug-in-play architecture. IMPACT: The explored updates performed together, along with the added future project considerations, has the potential to push the system performance to beyond 5000’, approaching the goal of one nautical mile.

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Apr 18th, 3:30 PM

Electro-Optical Grid Reference System (EOGRS) Receiver Optimization

Hager-Lubbers Exhibition Hall

PURPOSE: The EOGRS is defined as a relative navigation system. The system allows navigation with respect to the coordinates of a transmitter. The purpose of this project was to explore and implement optimizations to the existing prototype system. The goal of this overall system is to achieve one nautical mile (or ~6000 ft.). PROCEDURES: Examination of key components of the system were completed. Areas for improvement were chosen that had the potential for greatest impact on increasing the systems dynamic range. The chosen areas for optimization were Laser Modulation, Demodulation & Signal Processing, and Interface. Research, analysis, design, verification and demonstrations were then completed in each area. OUTCOME: First, the present modulation scheme was updated to M-PPM (P-2, M=12) to improve the pk to average optical power. Increasing the pk power by 4x would result in 2x distance improvement. M-PPM (P-2, M=12) is shown to increase the pk to average optical power from 2x to 6x while maintaining an acceptable BER and sub grid resolution. Second, the comparator demodulation was replaced with a discrete time signal processor, greatly improving receiver sensitivity, allowing for a dynamic demodulation threshold. This change improved the performance of the tested system from 1000’ to 2500’. Lastly, a new CAN Bus interface was chosen that allowed for a versatile plug-in-play architecture. IMPACT: The explored updates performed together, along with the added future project considerations, has the potential to push the system performance to beyond 5000’, approaching the goal of one nautical mile.