AG Kommunikationstheorie
Thema:
End-user Benefits of LTE Dual Connectivity in Heterogeneous Networks.Abstract:
New LTE features such as Dual Connectivity (DC) standardized in 3GPP Release 12 offer new ways for end user devices (UE) to aggregate radio resources from two distinct network nodes in order to achieve a higher throughput. For a radio network operator, these features offer new ways of traffic offloading and load balancing among multiple cells provided by multiple nodes. Thus, in order to achieve an optimum end user experience with the feature of DC, it is important to carefully distribute the internet traffic among both nodes and their radio resources. One typical internet traffic type today is webpage loading, based on HTTP and TCP/IP. Since these protocols depend on both RTT and achievable throughput, also the webpage load time, which is seen as a KPI for the end user experience depends on these metrics. The focus of this study is to analyze and optimize algorithms for traffic offloading from a primary to a secondary radio access in LTE Rel-12 Dual Connectivity (DC). Thereby, a realistic webpage traffic model is developed and considered, i.e. the end user experience (webpage load KPI) is the optimization target. Different offloading/load balancing/traffic routing options are identified, analyzed and developed, i.e. methods how a common packet data queue buffer (on PDCP layer) in the node providing the primary radio access can be split among primary radio access or the secondary access. The evaluation is conducted in one of Ericsson’s system level simulator capable of explicitly modeling all involved protocols. The final evaluation is done on system level, i.e. based on a realistic deployment scenario of a heterogeneous network with multiple macro and low-power nodes providing the primary and secondary radio access to the UE respectively.
Internship Seminar Presentation:
This short presentation is intended to describe shortly some tasks and procedures carried out as an intern in Qualcomm CDMA Technologies GmbH. The main goal of the internship was to get familiar with the Qualcomm GSM/GPRS/EDGE, UMTS/HSPA, LTE and its evolution solutions, as well as the associated protocol stacks (layers 1-3). Likewise, to learn how to analyze/debug problems which were found whilst testing.