Recently, the team led by Professor Zhou Linjie and Professor Lu Liangjun from the School of Integrated Circuits at Shanghai Jiao Tong University, in a collaborative effort with Huawei Technologies Co., Ltd.’s Wireless Technology Lab, put forward a fully connected microwave photonic multi-beamforming architecture. This architecture is based on silicon-based optical true-time delay line chips and is tailored to meet the demands of 5G/6G broadband wireless communications. The architecture has undergone experimental validation through outfield wireless communication tests.
With a fully connected design, this architecture ensures complete interconnection between every antenna element and all radio frequency chains. This not only optimizes the utilization of antenna elements but also enhances beamforming gain. Experiments reveal that, compared to partially connected schemes, the architecture achieves a 2.9 dB improvement in received signal amplitude gain at 13.1 GHz.
Moreover, by incorporating a 6-bit tunable silicon photonic true-time delay line, the issue of broadband wide-angle beam squint is effectively resolved. Within the 12.4-13.6 GHz frequency band, the beam direction remains frequency-independent. Furthermore, the architecture boasts a rapid beam switching speed of just 60 nanoseconds, aligning with the compatibility requirements of 5G/6G protocols and facilitating high-order modulation and high-quality broadband communications.