Recently demonstrated non-magnetic circulators rely on the interference between a linear periodically time-varying nonreciprocal gyrator and reciprocal passive microwave circuits, which limits their form factor and tunability. In this work, a new class of widely tunable non-magnetic inductorless nonreciprocal circulators based on harmonic engineering is introduced. LPTV circuits rely on modulating the input signal with a square-wave clock that contains multiple harmonics. The introduced harmonic engineering concept controls the response of the circuit to various harmonics of the clock waveform, the superposition of which results in the desired functionality. Two miniaturized $N$ -path Shekel circulators have been implemented in 65-nm CMOS. The first prototype, which uses a four-path structure operating in the large- $RC$ -regime, can be reconfigured for operation across 0.1–1.1 GHz with losses ranging from 2.5 to 3.4 dB. It has a form factor of $({\lambda ^{2}}/({2\times 10^{6}}))$ at 500 MHz, with a power consumption of 3–21 mW. The second prototype uses an eight-path structure and operates in the low- $RC$ -regime with a tuning range of 0.28–1.15 GHz and losses of 2.3–3.3 dB and achieves more than 20-dB isolation across a 233-MHz BW (38%) within a $({\lambda ^{2}}/({1.5\times 10^{6}}))$ form factor at 600 MHz consuming 26–67 mW of power. To date, this work has the smallest form factor reported among the state of the art.

中文翻译：

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无电感器，可调范围广 ñ谐波工程的多径谢克尔环行器

最近证明的非磁性环行器依赖于线性周期性时变的不可逆回旋器和可逆无源微波电路之间的干扰，这限制了它们的形状因数和可调性。在这项工作中，介绍了一种基于谐波工程的新型可广泛调谐的无磁无电感无可逆环行器。LPTV电路依靠包含多个谐波的方波时钟来调制输入信号。引入的谐波工程概念控制电路对时钟波形的各种谐波的响应，其叠加导致所需的功能。两个小型化 $ N $ 路径Shekel循环器已在65 nm CMOS中实现。第一个原型使用了四路径结构，该结构在大型， $ RC $ -regime，可以重新配置以在0.1–1.1 GHz范围内工作，损耗范围为2.5至3.4 dB。它的外形尺寸为 $（{\ lambda ^ {2}} /（{2 \ times 10 ^ {6}}））$ 在500 MHz时，功耗为3–21 mW。第二个原型使用八路径结构，并在低 $ RC $ 系统的调谐范围为0.28–1.15 GHz，损耗为2.3–3.3 dB，并且在233 MHz BW（38％）范围内实现了20 dB以上的隔离 $（{\ lambda ^ {2}} /（{1.5 \ times 10 ^ {6}}））$ 600 MHz时的外形尺寸消耗26-67 mW的功率。迄今为止，这项工作在现有技术中具有最小的外形尺寸。