Unequally Error Protected Wireless Data Transmission Using Channel State Information and Adaptive Encoders
Yaseen H. Tahir, Chee Kyun Ng, N. K. Noordin, B. A. Ali and S. Khatun
DOI : 10.3844/jcssp.2009.1095.1100
Journal of Computer Science
Volume 5, Issue 12
Problem statement: Higher data transmission rate with Quality of Services (QoS) guarantee is an important objective for wireless broadband communication systems. Unlike other communication system, real-time transmission requires high data rate and good error performance to ensure good quality of service. This study describes the design problem of real-time wireless data transmission which provides higher achievable data rate with Unequal Error Protection (UEP). Approach: Real-time data stream was divided equally into two streams, High Priority (HP) and Low Priority (LP) streams depending on their requirements. We considered these two bit streams as being encoded separately by two adaptive encoders. Feedback of Channel State Information (CSI) was used in adaptive physical layer channel for efficient use of the current available bandwidth by controlling the encoders. High code rate were used in both encoders when the channel is good while low code rate is otherwise. The two coded data streams were superimposed together with two different adjustable levels of power to achieve the UEP at the receiver end. Results: In this proposed scheme, same design metrics, namely, time, bandwidth and power were used to increase the transmission efficiency. Conclusion/Recommendations: Results showed that our scheme provided higher error performance for HP stream compared with other schemes that transmit using one power level data stream. The finding can be modified for studying the effects of fading on this system in future research.
© 2009 Yaseen H. Tahir, Chee Kyun Ng, N. K. Noordin, B. A. Ali and S. Khatun. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.