Energy Efficient Small-Cell Discovery Using Received Signal Strength Based Radio Maps

We consider the use of received signal strength based radio fingerprints to discover small cells in heterogeneous networks, deployed in a different carrier frequency as compared to a macro-cell network. We propose using a flexible fingerprint matching region around fingerprint reference locations in order to provide energy efficient small-cell discovery. We evaluate the scheme using extensive simulations in a heterogeneous network scenario, concentrating on the tradeoff between the energy consumed for discovering inter-frequency small cells and the offloading opportunity i.e. the fraction of time spent in the small-cell layer. Results show that we can save significant amount of battery power using fingerprint scheme with acceptable compromise in offloading opportunity.