Lower power consumption and up to 80% reduction in PCB size compared to IF
Supports high-density systems such as MIMO, beamforming, and radar array

As data rates and bandwidth requirements to satisfy high-bandwidth communication systems increase, interest in fast RF sampling is also increasing.

The problem is that there are many obstacles to overcome for fast and distortion-free RF sampling. For example, in a typical RF receiver, the RF frequency must be down-converted to the IF band through a mixer stage and a quadrature demodulator must be used, which inevitably causes unnecessary time and space as well as signal distortion.

Accordingly, there is a trend toward RF sampling receivers that eliminate quadrature modulators and synthesizers and replace them with RF ADCs that sample at high frequencies and sampling rates. Above all, it has the advantage of supporting high signal bandwidth and being able to directly sample the RF band.

Regarding the RF sampling structure, ARROW Korea’s Manager Sang-hyeok Han said, “By eliminating the RF mixer and synthesizer and the baseband components, the product size can be reduced, which in turn improves power loss.” He also said, “Bandwidth flexibility can be improved, which can support high-density systems such as MIMO, beamforming, and radar array.”

TI's ADC32RF45 is a 14-bit resolution ADC that uses RF sampling, providing faster and more flexible functions than conventional IF sampling. This ADC has 14-bit resolution and a sampling rate of 3 gigabits per second on dual channels, and supports bypass mode and full DDC mode. Also, the ADC32RF80 has 14-bit resolution and 3 gigabit-per-second sampling rate in dual channels, the same as the ADC32RF45, but the difference is that it only supports DDC mode.

In particular, TI's RF ADC, which applies the interleaving method, utilizes ADC cores with excellent SNR and SFDR performance and combines each ADC core to achieve high sampling speed and high bandwidth performance.

Regarding the problems that can occur due to interleaving, Manager Han explained, “Offset errors, amplitude errors, or phase errors can occur, but errors and noise can be reduced by performing continuous digital interleave correction in the digital correction block.”

The ADC 32RF45 has low power consumption and can reduce PCB size by up to 80% compared to the IF.