LTE-Advanced and Next Generation Wireless Networks: Channel Modelling and Propagation

Chapter 11

Finite-Difference Modeling

Guillaume la Roche

Mindspeed Technologies, France

Finite-Difference Time-Domain (FDTD) methods and similar approaches have been used for decades for radio wave simulation and field computation in small areas due to their high computational requirements. Furthermore, due to the increasing performance of personal computers, such approaches are more and more popular for the purpose of deterministic simulation of radio wave propagation. Therefore this chapter presents Finite Difference (FD) methods as an alternative to the popular ray tracing model presented in the previous chapter. We will demonstrate in this chapter that these techniques have interesting properties, mainly due to their simple implementations and high accuracy, that is why it is believed they can open the way towards very accurate simulations for LTE-advanced and beyond wireless networks. However there are also some technical challenges that will need to be addressed and will be discussed at the end of this chapter.

11.1 Introduction

FD methods, also referred to as Electromagnetic Model (EM) or full-wave equations, are aimed at solving Maxwell's equations, or other sets of equations derived from them, on a computer using some sort of domain-discretization.

With Long Term Evolution (LTE)-advanced and as detailed in Chapter 1 future wireless networks are expected to be more complex with higher numbers of cells. Therefore, software tools that aid in network optimization are necessary. ...