## 5 Verification by Field Measurements  
In order to verify the core functionality of the proposed QoS-SP-IM concept, a measurement campaign was carried out. Verifying the full concept requires extensive measuring trials across a large region so our measurement results focus on the femto coverage area and uplink noise rise contribution from HUEs _versus_ power settings, as well as interference scenario. We have performed co-channel measurements with a femtocell and a macrocell in the same frequency band (2132.4 MHz) and have ensured a very wide dynamic range of interference level from macro in our measurements, by performing the measurements at macrocell edge and macrocell center. The measurement campaign was carried out at the campus area of Tampere University of Technology (TUT). A Nokia Test Network (NTN) macrocell base station (3 GPP Release 6) provided macro coverage to the entire TUT  
Figure 10: HUE interference at nearest macro site _versus_ achieved uplink throughput. campus area. As the NTN is only used for test purposes, the network is considered empty after office hours and is ideal for simulation verification. The sector antenna of the macrocell base station was mounted on top of a nearby four-storey office building. For the measurement campaign, the HNB was deployed in offices, lecture rooms, or hallways at TUT and the chosen locations of the MNB and the HNB are shown in Figure 11.  
There are no buildings between the MNB and HNB location 4, hence LOS propagation, while a four-storey building is located in between the macro site and femto location 1, 2, and 3. Moreover, the distance between the MNB and the HNB locations varies between 250 m (Location 4) and 600 m (Location 1), while the MNB to HNB path loss was measured to 120 dB and 100 dB, for HNB location 1 and 4, respectively. Throughout the measurement campaign, a single HNB was deployed at the measurement location and the backhaul was public internet via TUT network. Most measurements were performed after office hours to minimize the possibility of having other active UEs in the network, _i.e._, minimize the uplink noise rise error. The HNBs, measurement UEs, and the measurement software were all 3 GPP Release 8 compliant [17, 18, 19, 20]. A key element for verification is the ability to predict the femtocell coverage zone accurately as function of set pilot and data power ratios. The CPICH power of the HNB was set to \(-10\) dBm. Next, the femto indoor coverage was measured at all four HNB locations with very different macro interference levels. The measurement UE was placed close to the HNB and connected to the HNB. The femto coverage was measured by walking away from the HNB while the UE was kept in connected mode. The distance was measured to the location where the measurement UE lost femto coverage or handed over to the surrounding macrocell. This procedure was repeated three times and the femto coverage was determined by averaging the three measurements. Figure 12 shows the measured femto coverage and the simulated femto coverage for similar RF conditions. Figure 11: HNB locations and MNB sector direction. Despite the small differences the simulation results are considered verified by the measurement results. For example, in the simulations, the femto antenna patterns are assumed to be omnidirectional, though, in reality, this is not true. Due to practical implementation imperfections, the actual antenna pattern varied up to \(\pm\)10 dB when measured in an anechoic radio chamber--the antenna pattern measurements are not presented in the paper. Consequently, the femto coverage area varies accordingly to the actual rotation of the HNB. Therefore, from Figure 12, the measurement and simulation results show a good match given the expected accuracy, with some underestimation happening when HNB is near to the macro center. Next, it was verified whether uplink noise rise from HUE is effectively predicted by the algorithm (9). The uplink noise rise caused by a single HUE was measured at locations 1 and 4.