Tower overlay over LTE-Advanced+ (TOoL+): Results of a field trial in Paris

Abstract

The system “Tower Overlay over LTE-Advanced+ (TOoL+)” is a solution developed to support mobile access networks to cope with the exponentially growing data traffic by offloading popular data to an LTE-based broadcast carrier transmitted from a High Tower, High Power (HTHP) infrastructure. As LTE-Advanced is specified for Low Tower, Low Power cellular networks, the term LTE-A+ reflects proposed additional features to the LTE standard like longer cyclic prefixes that are necessary to support the HTHP broadcast environment. Cooperative spectrum use can be achieved by transmitting LTE-A+ within DVB-T2 Future Extension Frames, forming a hybrid time-division multiplexed carrier whose capacity can be flexibly allocated to DVB-T2 and LTE-A+, respectively. This paper presents a field trial deployed in Paris, France, to evaluate TOoL+ in a demanding environment. The physical layer performance of different LTE-A+ broadcast modes and time-division multiplexing configurations is compared to that of LTE-Advanced and DVB-T2. Results show that LTE-A+ is suitable for an HTHP broadcast application and that the coverage area of LTE-A+ is similar to that of DVB-T2 when similar modulation and coding schemes are applied.