A passive, power-efficient double-quadrature down converter for sliding IF-architectures.

现代无线收发器的变频过程是制约整个系统性能和功耗的瓶颈。特别是对于传感器网络、医疗应用和其他网络物理系统等短距离无线通信，功耗要求严格。滑动中频结构对频率合成器和混频器所用高频驱动器的要求较低，在降低收发器功耗和提高系统性能方面具有很好的前景。此外，滑动中频结构也经常用于商用无线局域网收发器。本文提出了两种新型的无源混频器。在复域中进行频率转换。由于复域频率混合仅在第二混频器级中执行，第一种变型有利于低功耗。另一方面，这种变体的转换损失相对较高。第二种变体提供了完全复杂的频率转换，这意味着第一和第二混频器阶段都在复杂域中操作，导致完全的图像抑制。因此，与先进的无源正交滑动中频混频器相比，新型无源正交滑动中频混频器可以提供更小的转换损耗和低噪声系数。

The frequency conversion process of modern wireless transceivers is the bottleneck of the overall system performance and power consumption. Especially, for short range wireless communications such as sensor networks, medical applications and other cyber physical systems, power consumption requirements are strict. The sliding-IF architecture provides a very promising ability of reducing the transceiver power consumption and enhancing the system performance due to its relaxed requirement for frequency synthesizer and the high frequency drivers used for the mixer. Also the sliding- IF architecture is very often used in commercial WLAN transceivers. In this propose, two novel variants of passive mixers are presented. The frequency conversion is performed in the complex-domain. The first variant is advantageous for low power consumption due to the complex-domain frequency mixing being only executed in the second mixer stage. On the other hand, the conversion losses of this variant is relatively high. The second variant provides a fully complex frequency conversion which means both first and second mixer stages are operating in complex-domain, resulting in a completely image rejection. Therefore, compared to state of the art technology the novel passive quadrature sliding-IF mixer can offer significantly less conversion losses and low noise figure.