Preamble-Free Synchronization Based on Dual-chirp Waveforms for Photonic THz-ISAC

Journal of Lightwave Technology 2023
Zhidong Lyu, Lu Zhang, Hongqi Zhang, Zuomin Yang, Hang Yang, Lianyi Li, Changming Zhang, Vjačeslavs Bobrovs, Oskars Ozoliņš, Xiaodan Pang, Xianbin Yu

The integrated sensing and communication (ISAC) systems based on the linear frequency modulation (LFM) waveforms have attracted substantial attention. However, existing routines suffer from additional synchronization preamble overhead, which limits both communication and sensing performance. This work, using the dual-chirp with opposite slopes, exploits a preamble-free synchronization scheme for the LFM-based ISAC. We first theoretically analyze the quasi-orthogonal property of the proposed dual-chirp LFM waveform and derive its achievable communication rate and range ambiguity function. A photonics-assisted proof-of-concept ISAC experiment is conducted in the 300 GHz frequency band, achieving a 20 Gbps data rate with a distinguished peak sidelobe ratio (PSLR) of up to 29.2 dB and 1.5 cm range resolution. More importantly, less than 0.5% synchronous power overhead is needed in our scheme. In addition, the performance trade-off induced by the data rate and amplitude ratio is validated in the experiment, which is in line with our theoretical analysis. Therefore, the proposed scheme provides a promising solution for synchronizing LFM-based future ISAC systems. IEEE

Keywords
Bandwidth; Chirp; Dual-chirp waveform; Integrated sensing and communication (ISAC); Interference; Peak sidelobe ratio (PSLR); Photonics; Quasi-orthogonal; Sensors; Signal to noise ratio; Synchronization; Terahertz photonics
DOI
10.1109/JLT.2023.3344788
Hyperlink
https://ieeexplore.ieee.org/document/10366811

Lyu, Z., Zhang, L., Zhang, H., Yang, Z., Yang, H., Li, L., Zhang, C., Bobrovs, V., Ozoliņš, O., Pang, X., Yu, X. Preamble-Free Synchronization Based on Dual-chirp Waveforms for Photonic THz-ISAC. Journal of Lightwave Technology, 2023, , pp.1-9. ISSN 0733-8724. e-ISSN 1558-2213. Available from: doi:10.1109/JLT.2023.3344788

Publication language
English (en)