Design of Intelligent Cross-Layer Routing Protocols for Airborne Wireless Networks Under Dynamic Spectrum Access Paradigm
Abstract
The airborne military assets need to share the time-sensitive battlefield information among themselves, exchange the information with the ground troops for situational awareness purpose, and transfer it to the remotely located command and control center. The challenge in airborne networks (AN) is to organize a low-delay, reliable, infrastructure-less wireless network in the presence of highly dynamic network topology, heterogeneous air assets, intermittent transmission links and dynamic spectrum allocation. The QoS-aware cross-layer protocols are key enablers in effectively deploying the airborne infrastructure. This report considers the problem of designing cross-layer protocols for robust video transmission in mobile wireless networks, such as AN and wireless ad hoc networks (MANET). The cross-layer protocols need to consider the QoS issues in an end-to-end fashion and collaboratively design protocols at different network layers. First, a real-time and H.264 compliant video packet priority assignment scheme is discussed for error-prone wireless links in this report which can be deployed during H.264 encoding process with very small additional computational overhead. This packet priority assignment is used in an unequal error protection scheme by using the prioritized forward error correcting codes at the physical layer. In this scheme, low FEC code rates are used for higher priority packets and vice versa. Additionally a priority-aware MAC layer fragmentation scheme is designed for video packets in bit-rate limited error-prone wireless links. Specifically, the optimal fragment size is derived for each priority level which achieves the maximum expected weighted goodput at different encoded video bit rates and slice sizes. Packet fragmentation scheme also uses slice discard in the buffer due to the channel bit rate constraints. Both the cross-layer schemes demonstrate that the use of packet priority achieves considerable PSNR gain in the presence of channel errors.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 2011
- Accession Number
- ADA543607
Entities
People
- S. Kumar
Organizations
- San Diego State University