The increasing demand for wireless data bandwidth and the rapid adoption of LTE and LTE Advanced standards push radio-frequency (RF) IC designers to develop devices with higher levels of integrated RF functions, meeting more and more stringent specification levels. The substrates on which those devices are manufactured play a major role in achieving that level of performance [1]. In this paper, Soitec and UCL explain the value of using RF-SOI substrates and more especially the new generation of Soitec widely adopted eSI™ (enhanced Signal Integrity) substrate to achieve the RF IC performance requested to address the LTE Advanced smart phone market.