umber of active transmitter units and is independent of Ncells [5]. Some NR features require the BS to transmit from two or more antennas, for example, transmit diversity and multi-antenna transmission modes. For carrier aggregation, the car- riers may also be transmitted from different antennas. In order for the device to properly receive the signals from multiple antennas, the timing relationship between any two trans- mitter branches is specified in terms of the maximum time-alignment error between trans- mitter branches. The maximum allowed error depends on the feature or combination of features in the transmitter branches. In general, there is no maximum output power requirement for wide area base stations. As mentioned earlier, there is the maximum output power limit of 38 dBm for the medium range and 24 dBm for the local area base stations. In addition, 3GPP RF specifications spec- ify a tolerance, which defines the extent to which the actual maximum power may deviate from the power level declared by the BS manufacturer. Power control is used to limit the interference level. A total power control dynamic range per resource element is specified for a BS, which is the difference between the power of a resource element and the average resource element power for a BS at maximum output power (Pmax,c,TABC) for a specified ref- erence condition (Table 5.7). There is also a dynamic range requirement for the total BS power. The BS total power dynamic range is the difference between the maximum and the minimum transmit power of an OFDM symbol for a specified reference condition (Table 5.8). For TDD operation, a power mask is defined for the BS output power, defining the OFF power level during the uplink subframes and the maximum time for the transmitter transition time between the transmitter ON and OFF states [5]. Transmit OFF power requirements only apply to TDD mode of operation of an NR BS. The transmitter OFF power is defined as the mean power measured over 70/N(us) filtered with New Radio Access RF and Transce