Ultra-Wide Band On-Chip Circulators for Full-Duplex Communications

The thrust toward 5G communication has placed an increasing weight upon the performance bounds of current technologies. As the number of spectrum users continues to grow, the need for efficient use of spectral resources grows along with it. SSDL, which stands for Sequentially-Switched Delay Lines, provides a solution to this issue. The SSDL concept is a time-switching strategy, which uses a set of switches and transmission lines to simultaneously route transmitted and received waveforms to their respective ports over a broad bandwidth. SSDL does not incur a lower bound to its operating frequency, and experimental results of two different SSDL architectures demonstrate broadband non-reciprocity.