CMOS-integrated in-band full-duplex (IBFD) operation in wireless links and cryogenic quantum platforms was previously enabled by magnetic-free circulators using the phase non-reciprocity from spatial-temporal modulation. In this article, we present an alternative and simple integrated circuit scheme, which not only realizes non-reciprocal signal flows required for IBFD operations but also improves the isolation performance by completely eliminating any chip-level transmit (TX)-to-receive (RX) coupling. The above functions are enabled by performing a direction/frequency-independent, single-sideband down-conversion to the counter-propagating TX and RX signals, which creates opposite deviations of on-chip TX and RX frequencies with respect to the antenna (ANT) frequency. Such a principle also broadens the isolation bandwidth and enables integrated receiver down-mixing function. As a proof-of-concept, a 3.4–4.6-GHz (30% fractional bandwidth) IBFD interface is implemented using a 65-nm bulk CMOS technology. The measured TX-to-RX isolation of the circuit is 32–51 dB at 300 K, and 14–29 dB at 4.2 K. The measured TX-to-ANT and ANT-to-RX insertion losses are 3.0 and 3.2 dB at 300 K, and 1.9 and 2.0 dB at 4.2 K. At 300 K, the measured TX-to-ANT and ANT-to-RX IIP3 are 29.5 and 27.6 dBm, respectively. The IBFD core of the chip occupies an area of 0.27 mm ² and has a dc power (nominally consumed in an on-chip modulation clock generator) of 48 mW at 300 K and 42.6 mW at 4.2 K.

中文翻译：

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使用双边单边带频率转换在300和4.2 K下实现带内全双工操作

无线链路和超低温量子平台中的CMOS集成带内全双工（IBFD）操作以前是由无磁环行器使用时空调制实现的相位互易性启用的。在本文中，我们提出了一种替代且简单的集成电路方案，该方案不仅可以实现IBFD操作所需的不可逆信号流，而且还可以通过完全消除任何芯片级发射（TX）-to-receive（RX）来提高隔离性能。 ）耦合。通过对反向传播的TX和RX信号执行与方向/频率无关的单边带下变频，可以实现上述功能，这会导致片上TX和RX频率相对于天线（ANT）产生相反的偏差频率。这样的原理还拓宽了隔离带宽，并实现了集成的接收机缩混功能。作为概念验证，使用65nm批量CMOS技术实现了3.4–4.6 GHz（分数带宽的30％）IBFD接口。在300 K时，测得的电路TX-RX隔离度为32-51 dB，在4.2 K时为14-29 dB。测得的TX-ANT和ANT-RX插入损耗分别为3.0和3.2 dB。 300 K，在4.2 K时为1.9和2.0 dB。在300 K时，测得的TX-to-ANT和ANT-RX-IIP3分别为29.5和27.6 dBm。芯片的IBFD核心占用0.27毫米的面积 在300 K时，测得的TX至ANT和ANT至RX的插入损耗分别为3.0和3.2 dB，在4.2 K时为1.9和2.0 dB。在300 K时，测得的TX至ANT和ANT至RX的插入损耗IIP3分别为29.5和27.6 dBm。芯片的IBFD核心占用0.27毫米的面积 在300 K时，测得的TX至ANT和ANT至RX的插入损耗分别为3.0和3.2 dB，在4.2 K时为1.9和2.0 dB。在300 K时，测得的TX至ANT和ANT至RX的插入损耗IIP3分别为29.5和27.6 dBm。芯片的IBFD核心占用0.27毫米的面积 ²的直流功率（在片上调制时钟发生器中标称消耗）在300 K时为48 mW，在4.2 K时为42.6 mW。