Cognitive pilot channel: A radio enabler for spectrum awareness and optimized radio resource management

Today's wireless communications landscape is characterized by the coexistence of a plethora of disparate radio access technologies (RATs), which exhibit varying features in terms of capacity and coverage capabilities, mobility support etc. and also offer a great number of applications and services to different types of devices. In such a miscellaneous environment, mobile terminals are provided with a great set of options while setting up the parameters of their operation including among others the RAT, carrier frequency, and must also take into account the latest trend towards a flexible spectrum framework in heterogeneous radio access networks (RANs). As a result, in order to implement the optimal action, a mobile terminal needs to be enabled to acquire knowledge of its environment and established policies. Apart from mobilizing a rather time- and power-consuming operation such as spectrum sensing, the Cognitive Pilot Channel (CPC) concept has been proposed as a solution for providing the terminal with the necessary radio awareness at a given time and place, in a possible flexible spectrum management context. Framed within the above, this paper, developed within the E 3 project, aims at describing the CPC concept by showcasing its twofold role. First, as an enabler of the switch-on process for assisting the mobile terminal to camp onto the network side and second, as an enabler of an efficient decentralized and network-assisted radio resource management during the on-going communication phase.