Each RF-DAC in a tile has a number of optimized DSP features that can be used to implement Digital Up Conversion (DUC) and transmit signal filtering. These features are:
- Gen 1/Gen 2: Signal interpolation functionality—interpolation by 1 (bypass), 2, 4, or 8 is supported.
- Gen 3/DFE: Signal interpolation functionality—interpolation by 1 (bypass), 2, 3, 4, 5, 6, 8, 10, 12, 16, 20, 24, and 40 is supported. Enabling IMR mode will introduce an additional interpolation by 2 after the mixer.
- Coarse mixing (quarter and half rate) or fine mixing with a 48-bit frequency resolution numerically controlled oscillator (NCO).
- Compensation functionality containing a quadrature modulator correction (QMC) block with coarse delay adjustment block.
- Signal conditioning containing an inverse sinc FIR filter.
Single, multiple, or all DSP functions can be used or bypassed, using the Vivado IDE.
The following figure shows the available functions in an RF-DAC. Each function is described in the following sections.
Figure 1. Signal Treatment of the RF-DAC Peripherals