A teletraffic model for the Physical Downlink Control Channel in LTE

Recent advances in mobile handsets have led to new trends in mobile broadband data consumption, with a huge increase of signaling traffic generated by always-connected devices. Thus, a proper planning of control channels in mobile networks is necessary to avoid network capacity problems and provide an appropriate quality of service to the end user. A key issue in network planning is the availability of a complete and accurate system model. In this paper, an analytical performance model for the Long Term Evolution (LTE) Physical Downlink Control Channel (PDCCH) is constructed based on queuing theory. Unlike previous works, the proposed model considers important network features, such as link adaptation, and can be tuned with available network performance statistics. Model assessment is carried out by comparing performance estimates with request-level simulations and real performance measurements taken from a live LTE network. Results show that the proposed model can predict the PDCCH load distribution in a live network accurately.