Fig. 1.

Fig. 2.

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Fig. 4.

Fig. 5.

Fig. 6.
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Fig. 9.

Fig. 10.

Fig. 11.

Fig. 12.

Fig. 13.

Metrics of individual classes for the k-NN model
| Class | Recall | Precision | F1 |
|---|---|---|---|
| ‘East’ | 0.46 | 0.41 | 0.43 |
| ‘North’ | 0.34 | 0.43 | 0.38 |
| ‘South’ | 0.13 | 0.33 | 0.19 |
| ‘West’ | 0.64 | 0.50 | 0.56 |
Sample results of localization based on dual antenna RSSI readouts
| Classifier | MAE [m] | RMSE[m] | Stdev [m] |
|---|---|---|---|
| k-NN | 1.53 | 1.90 | 1.30 |
| MLP Classifier | 1.46 | 1.82 | 1.06 |
| Random Forest | 1.63 | 1.94 | 1.35 |
| SVM Classifier | 1.54 | 1.90 | 1.25 |
Quaternion mappings [17]
| BNO08X physical axis aligned | Mapping quaternion | |||||
|---|---|---|---|---|---|---|
| X | Y | Z | Qw | Qx | Qy | Qz |
| East | North | Up | 1 | 0 | 0 | 0 |
| North | West | Up | (√2)/2 | 0 | 0 | (√2)/2 |
| West | South | Up | 0 | 0 | 0 | 1 |
| South | East | Up | (√2)/2 | 0 | 0 | -(√2)/2 |
Class metrics for MLP Classifier
| Precision macro | Recall macro | F1 macro | Micro score | MCC |
|---|---|---|---|---|
| 0.37 | 0.37 | 0.36 | 0.41 | 0.18 |
Sample results of localization based on single antenna RSSI readouts
| Classifier | MAE [m] | RMSE[m] | Stdev [m] |
|---|---|---|---|
| k-NN | 1.61 | 2.00 | 1.38 |
| MLP Classifier | 1.64 | 1.99 | 1.10 |
| Random Forest | 1.65 | 1.97 | 1.47 |
| SVM Classifier | 1.55 | 1.98 | 1.43 |
Metrics of individual classes for the SVC model
| Class | Recall | Precision | F1 |
|---|---|---|---|
| ‘East’ | 0.46 | 0.42 | 0.44 |
| ‘North’ | 0.31 | 0.38 | 0.34 |
| ‘South’ | 0.27 | 0.22 | 0.24 |
| ‘West’ | 0.44 | 0.45 | 0.44 |
Class metrics for Random Forest Classifier
| Precision macro | Recall macro | F1 macro | Micro score | MCC |
|---|---|---|---|---|
| 0.31 | 0.34 | 0.31 | 0.41 | 0.16 |
Number of classes in the training set and their percentage share in the set
| West | East | North | South |
|---|---|---|---|
| 256 | 199 | 184 | 97 |
| 34,8% | 27,0% | 25,0% | 13,2% |
Number of classes in the test set and their percentage share in the set
| West | East | North | South |
|---|---|---|---|
| 39 | 28 | 29 | 15 |
| 35,1% | 25,2% | 26,1% | 13,5% |
Metrics for the SVC model
| Precision macro | Recall macro | F1 macro | Micro score | MCC |
|---|---|---|---|---|
| 0.37 | 0.37 | 0.37 | 0.39 | 0.16 |
Metrics for the k-NN model
| Precision macro | Recall macro | F1 macro | Micro score | MCC |
|---|---|---|---|---|
| 0.42 | 0.40 | 0.39 | 0.45 | 0.23 |