This work demonstrates the first non-reciprocal network based on switched low-loss acoustic delay lines. A 21 dB non-reciprocal contrast between insertion loss (IL=6.7 dB) and isolation (28.3 dB) has been achieved over a fractional bandwidth of 8.8% at a center frequency 155MHz, using a record low switching frequency of 877.22 kHz. The 4-port circulator is built upon a newly reported framework by the authors, but using two in-house fabricated low-loss, wide-band lithium niobate (LiNbO3) delay lines with single-phase unidirectional transducers (SPUDT) and commercial available switches. Such a system can potentially lead to future wide-band, low-loss chip-scale nonreciprocal RF systems with unprecedented programmability.
@article{arxiv.1801.03814,
title = {A Radio Frequency Non-reciprocal Network Based on Switched Low-loss Acoustic Delay Lines},
author = {Ruochen Lu and Tomas Manzaneque and Yansong Yang and Anming Gao and Liuqing Gao and Songbin Gong},
journal= {arXiv preprint arXiv:1801.03814},
year = {2019}
}