rate. When we sample at 245.76 MHz, the processing gain is calculated as 10*log10(245.75/100) =4 dB. Aggregate, it looks like we need a minimum of 12 + 2 + 15 + 10 + 25-4 = 60 dB or 10 Effective Number of Bits (ENOB). This is also enough precision to capture DPD feedback signals as we will be discussing later. The transmitter DAC dynamic performance requirements are dependent on the signal dynamic range which is calculated by doing an SNR budget analysis: Modulation Error Vector Magnitude (EVM). This is the EVM that is targeted by the system given a specific modulation type. EVM is standardized by 3GPP6,7 to 8% (64QAM) or 3.5% (256QAM). EVM can be converted from % to dB value SNR = -20log (EVM). Assuming 256QAM operation, assume an 29 dB EVM. SNR margin. Assume the transmitter DAC cannot degrade EVM by more than 0.25% (0.6 dB impact). Assuming the following equation for system SNR < System SNR = -20log (10-SNRA/10+10-SNRb/10 10-SNRn/101/2, this requires us to add 9 dB SNR margin. Headroom for Peak to Average Power Reduction (PAPR). Assume an 8 dB PAPR after applying Crest Factor Reduction (CFR). Gain/offset errors. Gain and offset errors as caused by inaccuracies in internal reference and amplifier offset voltages reduce the usable dynamic range. Assuming gain error and 162 Open Radio Access Network (O-RAN) Systems Architecture and Design offset errors to be 10% of full scale, then each contributes a 1 dB reduction in dynamic range. The DAC must be backed off 1 dB to prevent input clipping and another 1 dB to account for limited dynamic range. Add 2 dB dynamic range margin. Processing gain from oversampling-sampling above the minimum Nyquist requirement. Oversampling is good both because of the processing gain as well as because it simplifies the requirements on the external (analog) baseband reconstruction filter. Assuming a useful RF signal bandwidth of (say) 100 MHz which means a baseband signal rate of 50 MHz I and 50 MHz Q in a baseband ADC/DAC, implying a baseband sample rate of ~ 100 MHz to adhere to the N