Robust Multicasting in Micro Base Station Aided Wireless Cellular Networks

Efficient multicasting of critical messages is of essential importance in public safety and commercial multimedia cellular networks. We study the effectiveness of using the aid of micro base stations (mBSs) to enhance the spectral efficiency of multicast distribution in a wireless cellular network. Coloring oriented adaptive rate scheduling algorithms are considered, including such that temporally employ TDMA schedules with reuse levels of 1, 3, 4 and 7 over a cellular arrangement. These schemes are used to regulate multicast transmissions executed by macro base stations (MBSs) and to jointly schedule macro and micro base stations (mBSs). We examine the utility of using the aid of mBSs in potentially improving multicasting performance. We also examine a cellular system that has experienced the failure of some MBSs, and identify the adaptive rate coloring-based scheduling mechanism that should be used when a failover operation is pursued. For both pre-failure and post-failure scenarios, we show the schemes with that are aided by mBSs to achieve higher system throughput levels. We also show that when the inter site distance (ISD), identifying the range between MBSs, is lower than a threshold level, reuse-3 scheduling schemes (with or without employing mBSs) yield better performance than reuse-1 schemes. In turn, under longer ISD ranges (e.g., as employed in less dense cellular layouts), the spectral efficiency of the system can be significantly enhanced by using a joint scheduling and routing scheme that makes use of reuse-1 scheme with the aid of mBSs.