Processed 5G Signals Mathematical Models for Positioning Considering a Non-Constant Propagation Channel
The objective of this paper is to determine the ranging performance of the upcoming fifth generation (5G) signal. In order to do so, it is required to define 5G correlator outputs mathematical models. 5G systems will use OFDM (Orthogonal Frequency Division Multiplexing) signals; in the literature, mathematical models of OFDM signals are developed at the different receiver signal processing stages. These models assumed that the propagation channel is constant over an OFDM symbol; nevertheless, an in-depth study of QuaDRiGa, a 5G compliant propagation channel simulator, invalidates this hypothesis. Therefore, in this paper, mathematical models are developed that take into account the channel evolution. The focus is given on correlator outputs and results are applied to the computation of 5G based pseudo range accuracy.
The challenge of new communication architectures is to offer QoS in Internet networks. This paper investigates the QoS aspects in the NGN (Next Generation Networks), and especially in the wireless networks. Voice and video multimedia applications will be developed and used when QoS mechanisms will exist. Therefore new functions must be developed to guarantee performance, offer security, avoid jitter and to allow the respect of real-time constraints.