## 5 Feasibility Study Through System Simulations
### Scenario for Simulations, Area Intended for Positioning, and Positioning Area  
A scenario with an LOS radio propagation channel model is selected because it is a challenging scenario for fingerprinting-based positioning. Such a scenario is suitable for benchmarking positioning with spatial side information. Fingerprinting-based positioning exploiting RSS fingerprints benefits from abrupt changes in the RSS. For example, in [221], the abrupt change in the radio signal's strength through a wall is exploited to distinguish between different rooms. In [222], a physical arrangement consisting of an air-gap between attenuating surfaces is used to create a distinctive radiation pattern for the radio signal, which results in an abrupt change in the RSS. This abrupt change is tested for fingerprinting-based positioning against the signal strength that would be produced by an omnidirectional antenna without any object attenuating the radio signal. It is concluded that with such an abrupt change in the RSS, the positioning error is reduced. In [82], a reconfigurable intelligent surface is used to produce distinctive differences in the RSS in adjacent locations. Contrary to these research works, in our study, we intend to avoid such abrupt changes in the RSS so that the observed performance results are solely based on the gains produced by the spatial side information attained through the 2D sensor array. Therefore, we will assume an omnidirectional radiation pattern for the antennas of the transmitters and an LOS radio propagation channel model. To evaluate the proposed pattern-matching methods, the following scenario is proposed for the simulations. The scenario consists of an open area available for positioning with a maximum size of 13 m by 5 m. This open area is free of objects to allow the LOS propagation of the radio signal. Hereafter, this area is referred to as the _area intended for positioning_. The area intended for positioning spans from position 1 m to 14 m in the \(x\) coordinates and from position 1 m to 6 m in the \(y\) coordinates in the scenario. Positioning takes place within an area referred to as the _positioning area_ and which is inscribed in the area intended for positioning. So, in other words, the positioning area is a rectangle inscribed within the area intended for positioning, where the former can be smaller or equal to the latter. The positioning area is the actual area in which we study the different pattern-matching methods using simulations. It is noted that the positioning area can vary in size as a function of the selected tile sizes; however, it is constrained to a maximum size of \(13\times 5\) m\({}^{2}\) (the area intended for positioning in the scenario). Actually, we set a constraint on not allowing the use of fractions of a tile to cover the area intended for positioning. So, for some tile sizes, the positioning area will be equal to the area intended for positioning, and for other tile sizes, the positioning area will be slightly smaller than the area intended for positioning. The use of different tile sizes, border conditions, and the resulting positioning areas is discussed in Section 5.3. In the example that follows (Figure 12), the example in Section 5.2.4, as well as in the explanation of one of the results obtained (first example in Section 6.8.3), the area intended for positioning and the positioning area coincide. In contrast, in the second example presented in Section 6.8.3, the area intended for positioning and the positioning area differ. The difference between these areas can be observed in the figure of the second example in the cited section. The scenario is shown in Figure 12. In the figure, as an example, the area intended for positioning (13 m by 5 m) is fully covered by the positioning area with the selection of tiles with side lengths of 500 mm. In this case, the dimensions of the area intended for positioning, 13,000 mm \(\times\) 5000 mm, are multiples of the dimensions of the tile, and thus an exact number of tiles fits into the area intended for positioning.