Cross-Layer Optimization for Wireless Communication Networks
Design (CLD) has been widely studied and developed to optimize resource allocation
decisions in wireless communication networks. Various design schemes have been proposed
for the purpose of enhancing performance of resource restricted, error-prone wireless
networks. This dissertation presents two CLDs for wireless networks; one promotes
network energy efficiency, the oth... read moreer provides less resource-intensive optimization and
maximizes system reward. The energy efficient routing algorithm keeps records of
wireless sensors' energy levels, utilizes this information to determine routing
decisions at an upper layer. With this algorithm, network power consumption is
distributed among all sensors, which in turn prolongs the lifetime of the network.
Simulations and comparisons shown in the paper of energy conserving routing algorithm
demonstrate that this algorithm gains more than 40% improvement on energy saving over
the energy-efficient m-coverage and n-connectivity routing algorithm. This algorithm is
a CLD in which the network layer gets information about the physical layer, including
remaining energy and transmission power, to make better routing decisions in real time.
By contrast, the autonomous CLD accumulates information from lower layers, passes it to
upper layers. And vice versa. Each layer only communicates with its neighbors. Each
layer has its own optimizer which can be run in real-time to determine the best
transmission parameters in order to maximize the wireless user's system utility. This
optimization accounts for different Quality of Service (QoS) requirements involving
different communication protocols. Comparing to centralized optimization, which uses a
centralized optimizer to gather the environment dynamics of all layers before
calculating best transmission strategies for each layer, this solution requires less
computation time on the resource constrained wireless devices and adapts to various data
sources quickly. This theoretical model describes many practical networks. Ns-3
simulations of this algorithm for a Wi-Fi network demonstrate improved network
performance, including maximizing network throughput, which is almost doubled over an
unmanaged solution, lowering transmission cost by more than one half and reducing
transmission delay. Comparing the improved autonomous CLD with the original design
proposed by F. Fu et al., the improved version has more robust performance with more
transmission cost tolerance and faster optimization
Thesis (Ph.D.)--Tufts University, 2016.
Submitted to the Dept. of Electrical Engineering.
Advisor: Chorng Hwa Chang.
Committee: Alva Couch, Joseph Noonan, and Byung Kim.
Keyword: Computer engineering.read less