Towards 5G wireless systems: A modified Rake receiver for UWB indoor multipath channels

Abstract This paper presents a modified receiver based on the conventional Rake receiver for Ultra-Wide Band (UWB) indoor channels of femtocell systems and aims to propose a new solution to mitigate the multipath phenomenon. Furthermore, this work proposes an upgrade for the conventional Rake receiver to fulfill the needs of 5G wireless systems through a new concept named “hybrid femtocell” that joins UWB with millimeter wave (mmWave) signals. The modified receiver is considered to be a part of the UWB/mmWave hybrid femtocell system, where it is developed for confronting the indoor multipath channels and to ensure a flexible transmission based on an Intelligent Controlling System (ICS). Hence, we seek to exploit the circumstances when the channel is less complex to switch the transmission to a higher data rate through higher M-ary Pulse Position Modulation (PPM). Furthermore, an ICS algorithm is proposed and an analytical model is developed followed by performance studies through simulation results. The results show that using the UWB technology through the modified receiver in femtocells could aid in mitigating the multipath effects and ensuring high throughputs. Thus, the UWB based system promotes Internet of Things (IoT) devices in indoor multipath channels of future 5G.