Flexible and efficient use of free non-contiguous spectrum leveraging heterogeneous mobile network deployment scenarios is key to deploy 5G.  To maximize spectrum efficiency, Leti developed a 5G air interface technology that is both flexible and capable of mapping various services that ensures the best combinations of radio resources. This work has been performed in the framework of the Horizon 2020 project "FANTASTIC-5G", receiving funds from the European Union. 

Leti's paper "Block-Filtered OFDM: A new Promising Waveform for Multi-service Scenarios" introduced at ICC 2017 a new quasi-orthogonal multi-carrier waveform called Block-Filtered OFDM (BF-OFDM). Leti's BF-OFDM is an advanced post-OFDM waveform for 5G transmission, which overcomes the shortcomings inherent in conventional LTE waveforms. It also combines most of the advantages of classical waveforms such as CP-OFDM and FBMC. In fact, a performance comparison was conducted. Results showed that Leti's Block-Filtered OFDM offers the best compromise in terms of spectral efficiency, power spectral density, performance against multipath channel and performance in multi-user asynchronous scenarios… And last but not least, the highest flexibility.  

This 5G flexible waveform will be tested in Scotland by end of 2017 in a maritime broadband scenario at 690MHz. Leti already started working on 5G field trials early this year in Grenoble (Minatec Campus), leveraging a 3.5 GHz TDD band with 40MHz bandwidth.