Introduction
With the commercialization of the fifth generation (5G) wireless network and the exploration and development of its applications in vertical industries, the vision of the sixth generation (6G) wireless network has gradually attracted wide attentions. 6G wireless networks introduce new application scenarios while proposing higher performance indicators, such as seamless global connectivity, higher spectral- and energy-efficient, ultra-reliable communications, security, etc. In conventional networks, the transceiver module is a symmetrical architecture with independent radio frequency (RF) chains with high energy consumption components, such as power amplifiers. Nevertheless, a large number of accessed devices in 6G networks will inevitably lead to a sharp increase in power consumption. Therefore, the realization of high data rate with significantly reduced energy consumption and implementation cost for 6G wireless networks is still imperative.