A 16b 12GS/s Single/Dual-Rate DAC with Successive Bandpass Delta-Sigma Modulator Achieving <-67dBc IM3 Within DC-to-6GHz Tunable Passbands

📋 论文概要

该论文提出了一种16位12GS/s的单/双速率DAC，采用逐次带通Delta-Sigma调制器架构，实现了在DC至6GHz频率范围内低于-67dBc的三阶互调失真（IM3）。解决了灵活无线/有线发射机中需要高带内频谱纯度（SFDR和NSD）以及信号频带敏捷分配的问题。

💡 主要创新点

• 提出了逐次带通Delta-Sigma调制器架构，实现单/双速率操作，扩展了DAC的灵活性和可用频率范围。
• 通过独特的调制器设计，在12GS/s高采样率下实现了优异的线性度（IM3<-67dBc），覆盖DC-6GHz带宽。

🏷 关键词

📄 原文摘要

The agile allocation of signal bands over RF frequencies and high in-band spectral purity (both SFDR and NSD) can enable higher-order modulation in highthroughput flexible wireless/wireline transmitters, where signals are often channelized at certain center frequencies. Using a Nyquist DAC to cover the entire signal spectrum is thus unnecessary, as this trades the achievable dynamic range with the bandwidth. For such applications, a narrowband Nyquist DAC followed by a mixer, RF mixing DAC [1], or exploiting higher Nyquist zones [2] are typically adopted; these are either limited by deliverable output power or nearby spectral images due to lower input data rates. A dual-rate hybrid DAC [3] uses a deltasigma modulated LSB path to compensate for the non-idealities of the Nyquist path, allowing high linearity and a low noise floor within the Nyquist band while limiting out-of-band quantization noise. Still, this only synthesizes the baseband

👥 作者与机构

Shiyu Su, Mike Shuo-Wei Chen

University of Southern California, Los Angeles, CA