## 3 TVWS-DTV Coexistence: Field Measurements
### Field Tests Considering Long Distances
#### 3.2.1 Base Station and the Mobile Unit Setup  
A TVWS BS was strategically installed, and an MS was constructed to facilitate the measurement of the TVWS link's quality and its coexistence with DTV in different locations. The TVWS system used in the tests was the 5G-RANGE transceiver [43]. The installation site for the TVWS BS was the _Serra do Paredao_, also known as _\"Morro das 3 Torres\"_, on the border of the cities of Santa Rita do Sapucai and Sao Sebastao da Bela Vista, both in the state of Minas Gerais. The location features a masonry shelter and a tower where the antennas \begin{table}
\begin{tabular}{c l c c c c c c} \hline \hline
**DTV** & **Set-Top Box** & **1** & **2** & **3** & **1** & **2** & **3** \\ \cline{2-8}
**Channel** & **Link Length [m]** & & **15** & & & **50** & \\ \hline \multirow{4}{*}{26} & \(\text{P}_{\text{TX}}\) TVWS (CH28) [Wp] & \(0.040\) & \(3.55\) & \(3.55\) & \(0.79\) & \(7.94\) & \(3.98\) \\ \cline{2-8}  & \(\text{P}_{\text{RX}}\) DTV (CH26) [dBm] & \(-76.8\) & \(-76.7\) & \(-76.7\) & \(-76.8\) & \(-76.8\) & \(-76.8\) \\ \cline{2-8}  & \(\text{P}_{\text{RX}}\) TVWS (CH28) [dBm] & \(-31.6\) & \(-22.1\) & \(-22.1\) & \(-29.9\) & \(-19.8\) & \(-22.7\) \\ \cline{2-8} Interf. & \(\text{PR}_{n+2}\) [dB] & \(-45.2\) & \(-54.6\) & \(-54.6\) & \(-46.9\) & \(-57.0\) & \(-54.1\) \\ \cline{2-8} \(n+2\) & \(\text{ACPR}_{\text{UPPER}}\) [dB] & \(-6.0\) & \(1.0\) & \(1.0\) & \(-6.5\) & \(8.3\) & \(1.6\) \\ \cline{2-8}  & \(\text{ACPRlower}\) [dB] & \(-16.1\) & \(-16.1\) & \(-16.1\) & \(-16.2\) & \(-15.7\) & \(-16.0\) \\ \hline \multirow{2}{*}{30} & \(1\)-\(8\) & \(\text{P}_{\text{TX}}\) TVWS (CH28) [Wp] & \(0.32\) & \(3.55\) & \(3.55\) & \(0.40\) & \(7.94\) & \(3.98\) \\ \cline{2-8}  & \(\text{P}_{\text{RX}}\) DTV (CH30) [dBm] & \(-77.2\) & \(-77.1\) & \(-77.1\) & \(-77.1\) & \(-77.6\) & \(-77.0\) \\ \cline{2-8}  & \(\text{P}_{\text{RX}}\) TVWS (CH28) [dBm] & \(-32.2\) & \(-22.2\) & \(-22.2\) & \(-31.9\) & \(-20.3\) & \(-22.6\) \\ \cline{2-8} Interf. & \(\text{PR}_{n-2}\) [dB] & \(-45.0\) & \(-54.9\) & \(-54.9\) & \(-45.2\) & \(-56.4\) & \(-54.4\) \\ \cline{2-8} \(n-2\) & \(\text{ACPR}_{\text{UPPER}}\) [dB] & \(-15.8\) & \(-15.5\) & \(-15.5\) & \(-16.0\) & \(-14.2\) & \(-15.9\) \\ \cline{2-8}  & \(\text{ACPRlower}\) [dB] & \(-6.6\) & \(-0.2\) & \(-0.2\) & \(-6.6\) & \(8.2\) & \(0.1\) \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Test results with interference \(n-2\) and \(n+2\) at distances of \(15\) m and \(50\) m.  
were installed. Figure 9 presents photos of the shelter and tower on the left (Figure 9a), as well as the 5G-RANGE BS installed inside the shelter on the right (Figure 9b). The 5G-RANGE BS was again configured to employ GFDM with a BW of 5.571 MHz on channel 28 of the UHF band and with an initial power of 1 Wp in total (\(P_{\mathrm{TX}}\) TVWS). As 5G-RANGE employs a MIMO 2x2 technique, each antenna must transmit half of the total power allowed by the current regulation. Figure 10 shows the RF signal delivered to one of the BS transmission antennas. Figure 10: Spectrum of the GFDM signal transmitted by one of the antennas of the BS. Figure 9: BS installed in _Serra do Paredão_. (**a**) Shelter selected for installation. (**b**) 5G-RANGE BS installed and activated. Additionally, an MS is proposed to be installed in different locations. Figure 11a illustrates the block diagram that constitutes the MS. The setup includes a station for receiving the TVWS signal to investigate the communication link conditions of the 5G-RANGE system. This is the only block added compared to the setup presented for tests considering short distances. In other words, in addition to the TVWS Reception Station, the MS consists of a DTV Generation Station, consisting of a BTS player to generate the same BTS stream used in laboratory tests at the DTV modulator input, a Signal Combination Stage, a DTV Reception Station, and an isolated Spectrum Analyzer block.