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This work proposes an analytical model to investigate the behavior of a radio link control (RLC) protocol on the forward link of a mobile radio system and to relate its performance to transmission design. As a reference case, a multicarrier DS-CDMA architecture employing Walsh and quasi-orthogonal channelization codes, similar to the current cdma2000 system, is considered. Jointly modelling the features of the data link layer and of the underlying physical channels, it is possible to identify the interaction between transmission parameters and the RLC protocol behavior. The latter is assessed by analysis, determining the RLC protocol goodput and the average delivery time suffered by a data unit transferred over the radio channel, when two different coding approaches are adopted: namely, rate compatible punctured convolutional codes and code combining [ABSTRACT FROM PUBLISHER]

This paper proposes some novel techniques to accommodate users with different rate requirements in a wideband code-division multiple-access system employing orthogonal variable spreading factor codes. Two simple static code assignment strategies are first considered, and an improvement based on multicode assignment. Then the new idea of tree partitioning is introduced and used to devise a dynamic code reassignment algorithm. The behavior of these different techniques is experimentally investigated, in terms of call blocking probability and number of required reassignments. The tree partitioning method exhibits very good performances. [ABSTRACT FROM PUBLISHER]

Abstract-Alternative code assignment policies for the forward link of a multicarrier DS-CDMA system employing the recently proposed quasi-orthogonal sequences are put forth in this letter. It is demonstrated how different allocation strategies of quasi-orthogonal codes alter the interference level suffered by active units; it is also shown how to shape the rate of interference growth as a function of the number of active users within the reference cell, implementing some specific code allocation patterns. The performance achieved by various schemes is assessed in a frequency selective fading environment, in terms of average bit error probability. [ABSTRACT FROM PUBLISHER]

In this letter, an accurate analytic model to predict the send rate of the SQRT binomial congestion control protocol is derived, under the assumption that the protocol operates in an environment where the packet loss rate is relatively high. Based on this model, a study of its TCP-friendliness is performed, remarking the nonnegligible effects on fairness that different queue managements have. [ABSTRACT FROM PUBLISHER]