Graduation Year
2011
Document Type
Dissertation
Degree
Ph.D.
Degree Granting Department
Electrical Engineering
Major Professor
Wilfrido , Ph.D. Moreno
Keywords
communication, Processing, signal
Abstract
Wireless connectivity is becoming an integral part of our society. A new paradigm for
aeronautical data services is beginning to take shape. The advances in signal processing,
rapid prototyping, an insatiable consumer demand for Internet services, increase in aircraft
traffic, aircraft safety, etc., are driving the demand for high speed data services. Programs
led by the National Aeronautics and Space Administration (NASA), the Federal Aviation
Administration (FAA), EUROCONTROL and Networking the Sky for Civil Aeronautical
Communications (NEWSKY) are all looking into aeronautical platforms as part of their
Aeronautical Data Network (ADN). The desire is to provide low delay, cost effective and
high speed data connectivity for aeronautical platforms. The platforms can also be used
as a relay for ground and airborne nodes. Such a capability could potentially provide data
connectivity to remote areas. Most of the current high altitude platforms, i.e., aircraft,
provide data connectivity through a satellite. However, satellite resources are limited and
expensive, and they offer limited data throughput as compared to a terrestrial network. A
potential solution is connectivity to ground stations that can provide high speed physical
layers. Since the frequency spectrum is a valuable estate and needs to be used efficiently,
the use of spectrum efficient techniques are evaluated. This dissertation discusses issues
and challenges for developing a high speed ground based physical layer for aircraft and
proposes a novel solution. A detailed analytical analysis is presented to show the issues
related to aeronautical channel and its impacts to aeronautical communication system.
Specifically, the impact of Doppler shifts that limit the use of efficient modulation schemes,
such as Orthogonal Frequency Division Multiplexing (OFDM), is presented. OFDM is
sensitive to Doppler shifts. In addition, Doppler spread and shifts in aeronautical channels
depict different characteristics compared to terrestrial networks, i.e., multiple Doppler shifts
xi
and delays. Parametric techniques are investigated to accurately estimate the Doppler
shifts. The results of parametric methods for estimating the Doppler shifts are presented.
The simulation results of MUltiple Signal Classification (MUSIC), Eigenvector (EV) and
Minimum norm methods are considered for an aeronautical channel and their performances
is presented.
Scholar Commons Citation
Haque, Jamal, "An OFDM Based Aeronautical Communication System" (2011). Graduate Theses and Dissertations.
https://scholarcommons.usf.edu/etd/3143