Green Circular Economy Design Aspects for 6G Wireless Millimeter-Wave Transceivers

Application specific integrated circuits (ASICs) operating at millimeter-wave (MW) frequencies (30 to 300 GHz) are of key importance for future wireless communications. At present, MW transceivers are mainly optimized for high performance leading to a large DC power $\left(P_{D C}\right)$. In this paper, we propose a holistic design paradigm for wireless MW transceivers taking into account a wide range of green circular economy aspects. We discuss concepts to decrease $P_{D C}$ in operation and resource consumption in fabrication. We further discuss how to avoid toxicity and allow for a longer lifetime, DC supply via energy harvesting, batteryless operation and recycling. To demonstrate the feasibility of several of these concepts, we present the first selfsufficient supply of a 60 GHz CMOS on/off keying (OOK) data transmitter (TX) ASIC with highly-adaptive dutycycling. Since the required active solar cell area is only $4.5 \mathrm{mm}^{2}$, the way is paved for significantly advanced levels of miniaturization and resource saving for self-supplying MW-TX.