Ph.D. Thesis Defense

By

Pierre Valdez

(Advisor: Prof. Dimitri N. Mavris)

9:00 AM, Thursday, March 23, 2017

Weber Space Science and Technology Building (SST-II)

Collaborative Visualization Environment (CoVE)

A Methodology for the Optimization of Robust Unmanned Vehicle Communications in Maritime Environments

ABSTRACT:

As the military moves towards using more unmanned vehicles in the operational environment, accounting for communications during the mission planning phases is critical to meet the mission objectives. The quality of radio frequency (RF) and acoustic communications in maritime environments are highly dependent on the environmental conditions. Maritime atmospheric and underwater environments provide a complex medium for RF and acoustic communications that need to be accounted for to meet the robust and reliable communication requirements for unmanned vehicles.

This thesis proposes a methodology for predicting the communications network between unmanned vehicles using the Advanced Propagation Model to model the physics of RF electromagnetic wave propagation and probabilistic approaches to make the transmission channel robust to environmental conditions. In particular, a Nakagami-m transmission channel model is suggested for its ability to model a wide range of fluctuation intensities caused by environmental conditions. The stability of the network is assessed using the Finite State Markov Channel model through the use of state transition probabilities that lead to unstable transmission channel states. Network topologies composed of state-of-the-art unmanned vehicles with enhanced communications-based course of actions (COAs) to relay communications and guarantee connectivity and reliability are investigated. The methodology follows the Navy Planning Process closely to provide COAs and schedules that lead to optimal communication measures of performance of the mission.

The proposed methodology is demonstrated using the mine survey mission scenario. Results show the benefit of the proposed methodology over conventional approaches to survey target areas in a sea-base operational environment. The methodology is not a final product, but will be upgraded and integrated into the UV-Core environment to provide valuable information during mission planning phases to make crucial decisions and trade-offs.

Committee Members:

Prof. Dimitri Mavris (Advisor)

Prof. Eric Feron (AE)

Prof. Daniel P. Schrage (AE)

Dr. Kelly Griendling (AE)

Dr. Ayodeji Coker (Space and Naval Warfare Systems SPAWAR, San Diego CA)

Dr. Matthew Bays (Naval Surface Warfare Center, Panama City FL)