Scheduling and Codeword Length Optimization in Time Varying Wireless Networks

Abstract-- In this paper, a downlink scenario in which a singleantenna base station communicates with K single antenna users, over a time-correlated fading channel, is considered. It is assumed that channel state information is perfectly known at each receiver, while the statistical characteristics of the fading process and the fading gain at the beginning of each frame are known to the transmitter. By evaluating the random coding error exponent of the time-correlated fading channel, we show that there is an optimal codeword length which maximizes the throughput. We examine the throughput of the conventional scheduling that transmits to the user with the maximum signal to noise ratio using both fixed length codewords and variable length codewords. Although optimizing the codeword length improves the performance, it is shown that using the conventional scheduling, a gap of ( log log log K) exists between the achievable throughput and the maximum possible throughput of the system. We pr...

• Type: Journal
• Year: 2006
• Where: CORR
• Authors: Mehdi Ansari Sadrabadi, Alireza Bayesteh, Amir K. Khandani
• Keywords: Codeword Length, CORR 2006, Education, Throughput, Time-correlated Fading Channel