Type of Document Dissertation Author Wang, Ying Author's Email Address email@example.com URN etd-09302009-162117 Title Dynamic Cellular Cognitive System Degree PhD Department Electrical and Computer Engineering Advisory Committee
Advisor Name Title Bostian, Charles W. Committee Chair da Silva, Claudio R. C. M. Committee Member Hsiao, Michael S. Committee Member MacKenzie, Allen B. Committee Member Smith-Jackson, Tonya L. Committee Member Keywords
- Cognitive Radio
- Cognitive Radio Network
- Signal Classification and Synchronization
- Dynamic Spectrum Accessing
- Channel Allocation
- Software Defined Radio
Date of Defense 2009-09-25 Availability unrestricted AbstractDynamic Cellular Cognitive System (DCCS) serves as a cognitive network for white space
devices in TV white space. It is also designed to provide quality communications for first
responders in area with damaged wireless communication infrastructure. In DCCS network,
diverse types of communication devices interoperate, communicate, and cooperate with high
spectrum efficiency in a Dynamic Spectrum Access (DSA) scenario. DCCS can expand to a
broad geographical distribution via linking to existing infrastructure. DCCS can quickly form a
network to accommodate a diverse set of devices in natural disaster areas. It can also recover the
infrastructure in a blind spot, for example, a subway or mountain area. Its portability and low
cost make it feasible for commercial applications.
This dissertation starts with an overview of DCCS network. DCCS defines a cognitive radio
network and a set of protocols that each cognitive radio node inside the network must adopt to
function as a user within the group. Multiple secondary users cooperate based on a fair and
efficient scheme without losing the flexibility and self adaptation features. The basic unit of
DCCS is a cell. A set of protocols and algorithms are defined to meet the communication
requirement for intra-cell communications.
DCCS includes multiple layers and multiple protocols. This dissertation gives a comprehensive
description and analysis of building a DCCS network. It covers the network architecture,
physical and Medium Access Control (MAC) layers for data and command transmission,
spectrum management in DSA scenario, signal classification and synchronization and describes a
working prototype of DCCS.
Two key technologies of intra-cell communication are spectrum management and Universal
Classification and Synchronization (UCS). A channel allocation algorithm based on calculating
the throughput of an available is designed and the performance is analyzed. UCS is conceived as
a self-contained system which can detect, classify, and synchronize with a received signal and
extract all parameters needed for physical layer demodulation. It enables the accommodation of
non-cognitive devices and improves communication quality by allowing a cognitive receiver to
track physical layer changes at the transmitter.
Inter-cell communications are the backhaul connections of DCCS. This dissertation discusses
two approaches to obtaining spectrum for inter-cell communications. A temporary leasing
approach focuses on the policy aspects, and the other approach is based on using OFDMA to
combine separate narrowband channels into a wideband channel that can meet the inter-cell
communications throughput requirements.
A prototype of DCCS implemented on GNU radio and USRP platform is included in the
dissertation. It serves as the proof of concept of DCCS.
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