Analysis of an Adaptive Switching Point for LTE TDD by Dynamic System-Level Simulations


  • Christian Backfrieder University of Applied Sciences Upper Austria
  • Gerald Ostermayer University of Applied Sciences Upper Austria


This paper introduces an LTE system level simulator
and presents investigations of scenarios with differently balanced
traffic emergence between uplink and downlink as well as
inhomogeneous distribution of link direction asymmetry. In the
TDD mode of LTE, duplexing is implemented via sharing the
time domain between uplink and downlink users. This is done by
different switching configurations, which offer varying capacity
distributions between downlink and uplink, from a downlinkheavy
configuration with 90 percent of the capacity in downlink
direction to uplink heavy configurations with 60 percent uplink.
We utilize the available capacity perfectly by adjusting the link
configuration appropriately to traffic emergence. Performance
gains when selecting a configuration appropriate to the arising
traffic compared to usage of a static configuration with equally
distributed capacity are investigated. In case of different configurations,
additional interference can occur in neighbored cells
due to distinct communication direction at the same time. We
clarify the differences between these scenarios and quantify the
gains and losses when the switching point between uplink and
downlink is variable.

Author Biographies

Christian Backfrieder, University of Applied Sciences Upper Austria

Research Group Networks and Mobility, Department
of Mobile Computing

Gerald Ostermayer, University of Applied Sciences Upper Austria

Department of Mobile Computing


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