## 5 Feasibility Study Through System Simulations
### Consistency in the Comparison of the Results Among Scenarios with Different Tile Sizes  
To obtain a consistent comparison among scenarios with different tile sizes, we need to look at the consequences resulting from varying the 2D sensor array's size and, correspondingly, the tile size. The challenge is how to make consistent comparisons of the results among scenarios using different tile sizes. From one perspective, the tiling process produces, in some cases, for some tile sizes, an untiled stripe adjacent to the top and/or the right borders of the area intended for positioning. We recall that the tiling is carried out by starting to tile the scenario from one border to the opposite border using entire tiles. An untiled stripe occurs in cases in which the dimensions of the area intended for positioning (13,000 mm \(\times\) 5000 mm) are not a multiple of the side length of the tile. So, for some tile sizes, it is not possible to entirely fill the area intended for positioning from one border to the opposite border using entire tiles, as explained in Section 5.3. We recall that the actual area of the scenario used for positioning is determined by the grid of fixed tiles constructed in the tiling process, through the execution of the function \(FTileCenters()\) (Pseudocode 1). As a consequence, the tested scenarios do not all have exactly the same positioning area and do not all have the same density of samples close to the borders. In this regard, it is unclear at this point whether the distribution of the positioning errors for these cases will be slightly different to what could be obtained if an exact number of tiles fitted into the dimensions of the area intended for positioning (or, in other words, to the case in which the tiles cover the area intended for positioning entirely). From another perspective, the size of the 2D sensor array, and hence the tile, limits the useful area in which positioning can be performed. A position is associated with one point of the 2D sensor array--for example, the center of the tile. Bigger tile sizes do not have the resolution for performing positioning as close to the borders as smaller tiles do. In this context, smaller 2D sensor arrays, and correspondingly the tiles associated with them, will delimit a positioning area of a bigger size than the area delimited by bigger 2D sensor arrays. All in all, changing the size of the tile causes variations in the useful area of the scenario for performing the positioning, and this causes inconsistencies in the comparison of scenarios with different tile sizes. These inconsistencies are in the sense that we are not strictly using the same positioning area among different tile arrangements to compare the results, and that the density of samples close to the borders is different for different tile sizes. While it would be possible to make corrections to theoretically normalize all of the cases for a consistent comparison, in the sense of keeping a constant distance to the borders of the scenario for any tile arrangement, we instead adopt a pragmatic approach that represents the case of selecting a 2D sensor array of a given size in a real scenario. In this context, these inconsistencies are regarded as consequences resulting from the use of different tile sizes in the discretization of the positioning area. These consequences are proper to the arrangement considered. Then, certainly, the size of the 2D sensor array will affect how close to the borders we can perform the positioning, affect the size of the positioning area, and result in an uncovered area close to the borders in some cases. For the purpose of determining whether the use of spatial side information helps to reduce the positioning error, these inconsistencies are negligible. This observation is based on the results obtained, comparing the operating regions of the positioning errors for the different pattern-matching methods, and considering the effect of the samples close to the borders, as discussed in Section 6.