An Interleaving Structure for Guaranteed QoS in Real-Time Broadcasting Systems

Abstract

Abstract-Providing high-quality broadcast services for soft real-time applications over wireless networks such as CDMA2000, which have high bit error rates, requires the control of errors that occur during data transmission. Reed-Solomon (RS) forward error correction (FEC) in the medium access control (MAC) layer performs this role in 3G broadcast services. We propose new analytic models for predicting the performance of RS coding and its execution time, which take into account the memory property of a fading channel, different channel conditions, and a variable level of block interleaving. We identify RS decoding as a significant cause of variability in execution time, taking the form of jitter, which depends on the channel conditions. We analyze the size of buffer required to absorb the jitter under different channel conditions. We then formulate a trade-off between the performance of RS coding and the delay that it causes in transmitting a fixed amount of data with different levels of block interleaving. Finally, we show how to balance the quality with which content is presented against an acceptable buffering delay, which is very important to soft real-time applications, by using an adequate level of block interleaving. This study offers a guide for the provision of efficient broadcast services in real time with stochastically guaranteed quality.

Designing and predicting QoS of a wireless system for medical telemetry

“…This means that the expected execution time for decoding an ECB increases as the channel condition deteriorates, which is also true for the worst-case execution-time (WCET). We have also shown [18] that the WCET is relatively long in a slow fading environment when the steady-state PER is fixed. Thus, assuming that ε is in the range 0 to ε max , and that the mobility (V ) is in the range υ min to υ max , within the service area covered by a particular base station, the WCET occurs when the channel condition Φ is Φ W C , which corresponds to (ε max , υ min ).…”

“…2) Introduction of block interleaving: Block interleaving [18]- [20], in conjunction with an error-correcting code, is extensively used in wireless communication to protect transmitted data from bursts of errors. When errors occur in bursts, the majority of the codewords transmitted are either free of errors or contain a large number of successive errors.…”

The Impact of H.264 Non-Desynchronizing Bits on Visual Quality and its Application to Robust Video Decoding

“…For each QP, a random error (single-bit) is considered. In fact, there are several interleaving techniques that can combat the problem of burst errors in wireless communication channels by fully randomizing the errors [24], [25]. A single frame (between the 30th frame and the 60th frame) is randomly selected for error.…”

Predictable and Reliable ECG Monitoring over IEEE 802.11 WLANs Within a Hospital

“…The number of packets in each row of the buffer, M, determines the extent of data interleaving. 10 A high value of M disperses consecutive packets into different code words, which improves performance in the presence of time-varying shadowing. However, this comes at the cost of increased buffer requirements and buffering delays at the receiver.…”