Channel Allocation Method in CDMA Networks using Transmission Control Protocol

Abstract

As the Internet grows both in terms of users and available applications, one of the challenging issues is providing a fair and efficient allocation of the available network resources. The Transport Control Protocol (TCP), is the default transport layer protocol used on the Internet to provide reliable end-to-end communications. Modern digital communication technologies now allow wireless channel schedulers to rapidly change the allocated channel resources in response to channel conditions as well as user demands. This is achieved by changing parameters such as the coding rate, spreading factor, modulation scheme and link-layer retransmission rate. In current code division multiple access (CDMA) networks the high rate channels are achieved by reducing the spreading factor of the orthogonal Walsh codes. This essentially implies that only a few users can simultaneously share the high-rate channels at any time. Specifically, we propose a wireless channel scheduler that allocates different channel rates from a set of optimized rates to TCP sessions in response to their sending rates. In the context of a single TCP session, we develop a model to compute its long-term throughput under such a scheduler and use it for joint optimization of control variables to compute the set of optimal channel rates that are used by the scheduler. Therefore, the goal of this paper is to increase the TCP sending rate allocated in channel resources by viewing their performance and speed rate.