 offered per area element differs from the capacity requested by the users. © 2009 by Taylor & Francis Group, LLC Long Term Evolution: 3GPP LTE Radio and Cellular Technology One brute-force solution to this problem is to place more BSs per area, but this comes with much higher deployment costs because every base station needs its own access to the fiber backbone network. Future base stations cannot reuse the simple wired access that the global system for mobile communications (GSM)[5] over UMTS (universal mobile telecommunications system) BSs had due to their high access rate beyond 100 Mb/s. Investing these costs is economically feasible only if the number of subscribers increases at the same rate. This is unlikely because the penetration of mobile phones is already very high in modern societies. The same number of subscribers will demand more and more transmission rates, which makes the aggregate data rate of a cell the bottleneck in future wireless systems. Assuming that customers are not willing to pay more for the increasing demand, increasing the density of base stations does not seem economically reasonable. This discussion leads to the conclusion that more fundamental enhancements are necessary to meet the future requirements. Overcoming the Shannon bound with multiple antennas will raise the data rate in certain circumstances. In addition, the wireless network architecture itself can be modified. A radio cell can then con- tain a number of relay nodes (RNs), also called fixed relay stations (FRSs), that do not need any fiber access. This proposal has existed for quite a long time [16,30]. Both "multihop" and "relaying" in the following discussion refer to layer-2 store-and-forward relays [32] rather than to amplify-and-forward relays or coopera- tive relays [12]. Relays like these allow planning of radio cells and enable deploy- ment schemes for either coverage or capacity extension of a classical one-hop cell. In this method, the BS coordinates the partitioning of radio resources within the relay-enhanc