| 1. |
- Lyu, Zhidong, et al.
(author)
-
Multi-Channel Photonic THz-ISAC System Based on Integrated LFM-QAM Waveform
- 2024
-
In: Journal of Lightwave Technology. - : Institute of Electrical and Electronics Engineers (IEEE). - 0733-8724 .- 1558-2213. ; 42:11, s. 3981-3988
-
Journal article (peer-reviewed)abstract
- The integrated sensing and communication (ISAC) has been envisioned as a promising technology to simultaneously perform high-capacity communication and high-accuracy sensing with efficient resource utilization. Nevertheless, due to the severe mutual constraints between communication and sensing functions, the performance of previously reported ISAC demonstrations notably trails that of individual communication or sensing systems. In this work, an integrated LFM-QAM waveform is proposed and theoretically analyzed by combining linear frequency modulation (LFM) and quadrature amplitude modulation (QAM) formats. Employing the proposed waveform and optical wavelength division multiplexing (WDM) technique, we experimentally implement a multi-channel photonic terahertz (THz)-ISAC wireless system operating at 275 GHz band, simultaneously achieving a communication data rate up to 120 Gbps and a range resolution as high as 2.5 mm. To the best of our knowledge, this is the first time to demonstrate beyond 100 Gbps wireless data rate and mm-scale resolution based on an integrated waveform in the THz region, revealing the potential of THz-ISAC performance.
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| 2. |
- Yu, Xianbin, et al.
(author)
-
Terahertz Photonics in Radar and ISAC Applications
- 2023
-
In: 2023 Asia Communications and Photonics Conference/2023 International Photonics and Optoelectronics Meetings, ACP/POEM 2023. - : Institute of Electrical and Electronics Engineers (IEEE).
-
Conference paper (peer-reviewed)abstract
- This paper reviews our recent progress on photonic terahertz radar and integrated sensing and communication (ISAC) systems in the 300GHz band with distinguished sensing performance.
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| 3. |
- Kerrebrouck, Joris Van, et al.
(author)
-
726.7-Gb/s 1.5-μm single-mode VCSEL discrete multi-tone transmission over 2.5-km multicore fiber
- 2018
-
In: 2018 Optical Fiber Communications Conference and Exposition, OFC 2018 - Proceedings. - : Institute of Electrical and Electronics Engineers Inc.. - 9781943580385 ; , s. 1-3
-
Conference paper (peer-reviewed)abstract
- A 107Gb/s net-rate DMT optical signal was generated using a single-mode long-wavelength VCSEL with a modulation bandwidth of 23 GHz. We experimentally demonstrated a total net-rate up to 726.7Gb/s at 1.5μm over 2.5km 7-core dispersion-uncompensated MCF.
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| 4. |
- Li, Lianyi, et al.
(author)
-
THz-Over-Fiber System With Orthogonal Chirp Division Multiplexing for Integrated Sensing and Communication
- 2024
-
In: Journal of Lightwave Technology. - : Institute of Electrical and Electronics Engineers (IEEE). - 0733-8724 .- 1558-2213. ; 42:1, s. 176-183
-
Journal article (peer-reviewed)abstract
- To achieve integrated sensing and communication (ISAC) applications with high data rates and high resolution, the terahertz-over-fiber (ToF) system has been recognized as a promising solution. However, the frequency-selective fading would deteriorate the performance of the ToF-based ISAC systems. In this work, we propose the orthogonal chirp division multiplexing (OCDM) waveform-based ToF system for high-performance ISAC applications. The system encodes data with the phase of the sub-chirps and obtains radar images by processing echoes with the zero-padded matched filtering algorithm. We experimentally demonstrate a proof-of-concept OCDM-ToF system, which simultaneously achieves a 32 Gbit/s data rate and 1.875 cm range resolution after transmission over a 10 km optical fiber and a 3.14 m wireless link at the THz band, for the first time. The experimental results indicate that the OCDM-ToF system can enhance robustness against the frequency-selective fading issue, as a benefit improving communication performance with high data rates while preserving the high sensing resolution of OFDM in the THz ISAC applications.
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| 5. |
- Lyu, Zhidong, et al.
(author)
-
A Beam-Scannable Photonic THz-ISAC System Based on Risley Prisms
- 2023
-
In: 2023 Asia Communications and Photonics Conference/2023 International Photonics and Optoelectronics Meetings, ACP/POEM 2023. - : Institute of Electrical and Electronics Engineers (IEEE).
-
Conference paper (peer-reviewed)abstract
- We demonstrate a beam-scannable photonic terahertz-integrated sensing and communication (THz-ISAC) system using Risley prisms. 20 Gbps data rate and 1.5 cm resolution are simultaneously achieved at 300 GHz with 40 deg field of view (FoV).
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| 6. |
- Lyu, Zhidong, et al.
(author)
-
Multi-Channel Photonic THz-ISAC System Based on Integrated LFM-QAM Waveform
- 2024
-
In: Journal of Lightwave Technology. - : Institute of Electrical and Electronics Engineers Inc.. - 0733-8724 .- 1558-2213. ; 42:11, s. 3981-3988
-
Journal article (peer-reviewed)abstract
- The integrated sensing and communication (ISAC) has been envisioned as a promising technology to simultaneously perform high-capacity communication and high-accuracy sensing with efficient resource utilization. Nevertheless, due to the severe mutual constraints between communication and sensing functions, the performance of previously reported ISAC demonstrations notably trails that of individual communication or sensing systems. In this work, an integrated LFM-QAM waveform is proposed and theoretically analyzed by combining linear frequency modulation (LFM) and quadrature amplitude modulation (QAM) formats. Employing the proposed waveform and optical wavelength division multiplexing (WDM) technique, we experimentally implement a multi-channel photonic terahertz (THz)-ISAC wireless system operating at 275 GHz band, simultaneously achieving a communication data rate up to 120 Gbps and a range resolution as high as 2.5 mm. To the best of our knowledge, this is the first time to demonstrate beyond 100 Gbps wireless data rate and mm-scale resolution based on an integrated waveform in the THz region, revealing the potential of THz-ISAC performance.
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| 7. |
- Lyu, Z., et al.
(author)
-
Preamble-Free Synchronization Based on Dual-chirp Waveforms for Photonic THz-ISAC
- 2024
-
In: Journal of Lightwave Technology. - 0733-8724 .- 1558-2213. ; 42:8, s. 2657-
-
Journal article (peer-reviewed)abstract
- 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.
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| 8. |
- Lyu, Zhidong, et al.
(author)
-
Preamble-Free Synchronization Based on Dual-chirp Waveforms for Photonic THz-ISAC
- 2024
-
In: Journal of Lightwave Technology. - : Institute of Electrical and Electronics Engineers (IEEE). - 0733-8724 .- 1558-2213. ; 42:8, s. 2657-2665
-
Journal article (peer-reviewed)abstract
- 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.
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| 9. |
- Qiao, Mengyao, et al.
(author)
-
60 Gbit/s PAM-4 wireless transmission in the 310 GHz band with nonlinearity tolerant signal processing
- 2021
-
In: Optics Communications. - : Elsevier BV. - 0030-4018 .- 1873-0310. ; 492
-
Journal article (peer-reviewed)abstract
- We experimentally demonstrate a terahertz (THz) photonic wireless transmission system in the 310 GHz band with four-level pulse amplitude modulation (PAM-4) signals. A zero-bias diode is used as a simple direct detection receiver, which is cost-effective compared to a conventional coherent receiver. Moreover, we comprehensively investigate the system performance by applying linear and nonlinear equalization schemes. The experimental results show that Volterra nonlinear filtering can significantly improve the system capacity by around 90%, and transmissions of up to 60 Gbit/s PAM-4 signals over a 3 m wireless link are successfully achieved. The advantageous features of this make it promising for high-speed THz wireless communications.
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| 10. |
- Yu, Xianbin, et al.
(author)
-
Multi-dimensional Multiplexed Fiber-Wireless Transmission in the THz Band
- 2022
-
In: Proceedings of the 2022 Conference on Lasers and Electro-Optics Pacific Rim, CLEO/PR 2022. - : Optica Publishing Group.
-
Conference paper (peer-reviewed)abstract
- We propose and experimentally demonstrate multi-dimensional multiplexed THz photonic wireless communication systems, achieving wireless net data rates of up to 510 Gbit/s and 1.059 Tbit/s in the 350 GHz band.
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| 11. |
- Yu, Xianbin, et al.
(author)
-
Multi-dimensional Multiplexed Fiber-Wireless Transmission in the THz Band
- 2022
-
In: 2022 Conference on Lasers and Electro-Optics Pacific Rim, CLEO-PR 2022 - Proceedings. - : Institute of Electrical and Electronics Engineers (IEEE).
-
Conference paper (peer-reviewed)abstract
- We propose and experimentally demonstrate multi-dimensional multiplexed THz photonic wireless communication systems, achieving wireless net data rates of up to 510 Gbit/s and 1.059 Tbit/s in the 350 GHz band.
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| 12. |
- Yu, Xianbin, et al.
(author)
-
Photonic-wireless Communication and Sensing in the Terahertz Band
- 2023
-
In: 2023 OPTICAL FIBER COMMUNICATIONS CONFERENCE AND EXHIBITION, OFC. - : Institute of Electrical and Electronics Engineers (IEEE).
-
Conference paper (peer-reviewed)abstract
- This paper reviews the potential of THz photonics in communication and sensing by presenting our experimental results in the 300-500 GHz. Benefiting from the large available bandwidth in both THz and photonics, THz communications with high speed and THz imaging with high resolution have been achieved.
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| 13. |
- Zhang, Hongqi, et al.
(author)
-
300 GHz photonic-wireless transmission with aggregated 1.034 Tbit/s data rate over 100 m wireless distance
- 2024
-
In: 2024 Optical Fiber Communications Conference and Exhibition, OFC 2024 - Proceedings. - : Institute of Electrical and Electronics Engineers Inc..
-
Conference paper (peer-reviewed)abstract
- We present a long-distance ultrafast THz photonic-wireless communication system by combining frequency-, polarization- and spatial- division multiplexing techniques. An aggregated net rate of 1.034 Tbit/s over record 100 m at 300 GHz is successfully demonstrated.
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| 14. |
- Zhang, H., et al.
(author)
-
Aggregated 1.059 Tbit/s photonic-wireless transmission at 350 GHz over 10 meters
- 2021
-
In: 2021 Opto-Electronics and Communications Conference, OECC 2021. - : Institute of Electrical and Electronics Engineers Inc..
-
Conference paper (peer-reviewed)abstract
- We report on a multi-dimensional multiplexed THz photonic wireless communication system. A record aggregated net rate of 1.059 Tbit/s over a wireless distance of 10 m in the 350 GHz band is experimentally demonstrated.
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| 15. |
- Zhang, Hongqi, et al.
(author)
-
Broadband terahertz equivalent-Time sampling system based on a photoconductive antenna
- 2023
-
In: 2023 International Topical Meeting on Microwave Photonics, MWP 2023 - Proceedings. - : Institute of Electrical and Electronics Engineers (IEEE).
-
Conference paper (peer-reviewed)abstract
- In recent years, remarkable achievements have been witnessed in developing terahertz (THz) communication systems with high data rates. However, the analyzers/receivers of most THz communication systems still heavily rely on electronic circuits with limited bandwidth, obstructing the further exploration of THz resource. In this work, an equivalent-Time sampling (ETS) system based on a conventional photoconductive antenna (PCA) is proposed for capturing high-speed THz signals. The PCA is excited by ultrashort optical pulses from a low repetition-rate mode-locked laser (MLL) and hence alternates the sampling of high-speed THz signals into low-frequency domain. The proposed ETS system for THz signals is theoretically analyzed and experimentally demonstrated. In the proof-of-concept experiment, an on-off keying (OOK) signal with a baud rate of 15 Gbaud are successfully sampled and evaluated. The proposed THz ETS system can be easily accessible by low-speed electronics, which is expected to bring new opportunities for high-speed THz time-domain analyzer.
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| 16. |
- Zhang, Hongqi, et al.
(author)
-
Tbit/s Multi-Dimensional Multiplexing THz-Over-Fiber for 6G Wireless Communication
- 2021
-
In: Journal of Lightwave Technology. - : Institute of Electrical and Electronics Engineers (IEEE). - 0733-8724 .- 1558-2213. ; 39:18, s. 5783-5790
-
Journal article (peer-reviewed)abstract
- Photonics-aided terahertz (THz) wireless systems have been progressively developed to accommodate the forthcoming wireless communication with extremely high data rates in recent years. However, restrained by the obtainable signal-to-noise ratio (SNR) and the dimensions explored in THz photonic wireless systems, achieving data rates of Tbit/s and beyond is still challenging. In this paper, we present a multi-dimensional multiplexing Tbit/s THz-over-Fiber wireless communication system, by efficiently benefiting from the multiplexing gain in both optical wavelength and space domains. Enabled by a combined routine of an optical frequency comb, a low inter-core crosstalk (IC-XT) multi-core fiber and advanced digital signal processing, a line rate of up to 1176 Gbit/s over a wireless distance of 10 m in the 350 GHz band is experimentally demonstrated without any THz amplifiers, resulting in a net data rate of up to 1059 Gbit/s. To the best of our knowledge, this is the first time that beyond Tbit/s wireless data rate is successfully achieved in the THz region above 300 GHz, making a significant contribution to the development of THz-over-Fiber systems for the sixth generation (6G) wireless communication.
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| 17. |
- Zhang, Lu, et al.
(author)
-
Nonlinearity-aware optoelectronic terahertz discrete multitone signal transmission with a zero-bias diode
- 2020
-
In: Optics Letters. - : The Optical Society. - 0146-9592 .- 1539-4794. ; 45:18, s. 5045-5048
-
Journal article (peer-reviewed)abstract
- The terahertz band has been recognized as a promising candidate to support future rate-greedy applications such as 6G communications. Optoelectronic terahertz communications are beneficial for the realization of high-speed transmission. In this Letter, we propose and experimentally demonstrate an optoelectronic terahertz transmission system with intensity modulation and direct detection, where a discrete multitone (DMT) waveform with high-order quadrature amplitude modulation (QAM) is used. A zero-bias diode (ZBD) is used in the system as a simple, cost-effective direct detection terahertz receiver. A nonlinearity-aware digital signal reception routine is proposed to mitigate the nonlinear impairments induced by subcarrier-to-subcarrier beating interference from the ZBD. In this experiment, up to a 60 Gbit/s line rate 16QAM-DMT signal is successfully transmitted over a 3 m wireless link in the 310 GHz band, and the mean signal-to-noise ratio is improved by 3 dB with nonlinearity-aware signal processing routine. The advantageous features of such a scheme make it a promising solution for terahertz wireless communications.
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| 18. |
- Bai, Liga, et al.
(author)
-
Performance Analysis of Multicarrier Modulation Waveforms for Terahertz Wireless Communication
- 2023
-
In: 2023 21st International Conference on Optical Communications and Networks, ICOCN 2023. - : Institute of Electrical and Electronics Engineers (IEEE).
-
Conference paper (peer-reviewed)abstract
- This paper presents an experimental comparison among the orthogonal frequency division multiplexing (OFDM), filter bank multicarrier (FBMC) and orthogonal time frequency space (OTFS) waveforms in a terahertz photonic-wireless point-to-point communication system operating at 300GHz. Our results show that, all waveforms have similar peak-to-average power ratio (PAPR), the OTFS and OTFS waveforms can achieve comparable bit error rate (BER) performance, while the FBMC waveform outperforms in terms of the out-of-band decay at the cost of non-orthogonality between subcarriers, leading to the deterioration of BER performance at high signal-to-noise ratio (SNR) region.
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| 19. |
- Daniel, Quentin, et al.
(author)
-
Water Oxidation Initiated by In Situ Dimerization of the Molecular Ru(pdc) Catalyst
- 2018
-
In: ACS Catalysis. - : AMER CHEMICAL SOC. - 2155-5435. ; 8:5, s. 4375-4382
-
Journal article (peer-reviewed)abstract
- The mononuclear ruthenium complex [Ru(pdc)L-3] (H(2)pdc = 2,6-pyridinedicarboxylic acid, L = N-heterocycles such as 4-picoline) has previously shown promising catalytic efficiency toward water oxidation, both in homogeneous solutions and anchored on electrode surfaces. However, the detailed water oxidation mechanism catalyzed by this type of complex has remained unclear. In order to deepen understanding of this type of catalyst, in the present study, [Ru(pdc)(py)(3)] (py = pyridine) has been synthesized, and the detailed catalytic mechanism has been studied by electrochemistry, UV-vis, NMR, MS, and X-ray crystallography. Interestingly, it was found that once having reached the Ru-IV state, this complex promptly formed a stable ruthenium dimer [Ru-III(pdc)(py)(2)-O-Ru-IV(pdc)(py)(2)](+). Further investigations suggested that the present dimer, after one pyridine ligand exchange with water to form [Ru-III(pdc)(py)(2)-O-Ru-IV(pdc)(py)(H2O)](+), was the true active species to catalyze water oxidation in homogeneous solutions.
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| 20. |
- Deng, Qiuzhuo, et al.
(author)
-
Quantum Noise Secured Terahertz Communications
- 2023
-
In: 2023 OPTICAL FIBER COMMUNICATIONS CONFERENCE AND EXHIBITION, OFC. - : Optica Publishing Group.
-
Conference paper (peer-reviewed)abstract
- The quantum noise based terahertz signal encryption scheme is proposed, a 16 Gbits(-1) secure terahertz communication system at 300 GHz with the optical communication realms is demonstrated, taking a significant step toward high-security wireless communications.
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| 21. |
- Deng, Qiuzhuo, et al.
(author)
-
Quantum Noise Secured Terahertz Communications
- 2023
-
In: 2023 Optical Fiber Communications Conference and Exhibition (OFC).
-
Conference paper (peer-reviewed)abstract
- The quantum noise based terahertz signal encryption scheme is proposed, a 16 Gbits-1 secure terahertz communication system at 300 GHz with the optical communication realms is demonstrated, taking a significant step toward high-security wireless communications.
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| 22. |
- Jia, Shi, et al.
(author)
-
2 x 300 Gbit/s Line Rate PS-64QAM-OFDM THz Photonic-Wireless Transmission
- 2020
-
In: Journal of Lightwave Technology. - : Institute of Electrical and Electronics Engineers (IEEE). - 0733-8724 .- 1558-2213. ; 38:17, s. 4715-4721
-
Journal article (peer-reviewed)abstract
- The proliferation of wireless broadband services have significantly raised the demand for high data rates. Due to the limited bandwidth of radio frequency (RF) bands that are currently in use for communication purposes, the choice of the 'Terahertz (THz) frequency region' (0.3-10 THz) is getting favored thanks to its merits of bringing together wireless and optical communications with photonics technologies. We report on an experimental demonstration of a hybrid THz photonic-wireless transmission based on a THz orthogonal polarization dual-antenna scheme. Probabilistic shaped 64-ary quadrature amplitude modulation based orthogonal frequency division multiplexing (64QAM-OFDM) modulation format is used to realize high transmission rate. A potential total system throughput of 612.65 Gbit/s (around 2 x 300 Gbit/s line rate) with an average net spectral efficiency of 4.445 bit/s/Hz per antenna is successfully achieved.
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| 23. |
- Jia, S., et al.
(author)
-
A unified system with integrated generation of high-speed communication and high-resolution sensing signals based on THz photonics
- 2018
-
In: Journal of Lightwave Technology. - : Institute of Electrical and Electronics Engineers Inc.. - 0733-8724 .- 1558-2213. ; 36:19, s. 4549-4556
-
Journal article (peer-reviewed)abstract
- Multifunctional convergence is one of the key physical features in future generation networks and Internet of things architectures. In this paper, we propose and experimentally demonstrate a unified terahertz (THz) system operating in the 300 GHz band, with a potential of simultaneously enabling high-speed communication and high-resolution ranging over a common optical infrastructure. Both THz communication and THz sensing signals are generated based on THz photonics and cutting-edge terahertz transceiver technologies. In the experiment, 16-quadrature amplitude modulation modulated THz signal is generated by photo-mixing two free running lasers for the communication, and linear frequency modulated (LFM) THz pulses are generated based on optical interferometer-based frequency-to-time mapping (FTM) for sensing. The experimental results show that up to 56 Gbit/s net rate is successfully transmitted over a 2 m free-space line-of-sight link, and the THz LFM pulses with a time-bandwidth product of up to 207 are successfully generated, which is potentially able to enable a cm-scale range resolution. We also investigate the frequency multiplexing schemes for two signals by changing the channel gap at the transmitter side. To the best of our knowledge, such a system represents the first demonstration of integrated generation system in the THz region above 300 GHz, which has great potential in prospective applications of future converged networks.
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| 24. |
- Lyu, Zhidong, et al.
(author)
-
Radar-Centric Photonic Terahertz Integrated Sensing and Communication System Based on LFM-PSK Waveform
- 2023
-
In: IEEE transactions on microwave theory and techniques. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9480 .- 1557-9670. ; 71:11, s. 5019-
-
Journal article (peer-reviewed)abstract
- The radar-centric terahertz integrated sensing and communication (THz-ISAC) is identified as a significant application in future wireless access networks. Up to date, previously reported demonstrations regarding radar sensing performance lack sufficient support in a complex environment with a strong target masking effect. This work tacks this problem by proposing a radar-centric waveform combining linear frequency modulation (LFM) waveform and phase shift keying (PSK). We first derive sensing metrics of the LFM-PSK waveform through theoretical analysis, including range resolution, peak sidelobe ratio (PSLR), and Cramér-Rao lower bound (CRLB). Then a proof-of-concept experiment on a photonics-assisted integrated sensing and communication (ISAC) system operating at 330 with 18 GHz bandwidth is conducted to verify the performance of the proposed LFM-PSK waveform. In the experiment, the proposed waveform can reach a PSLR of up to 20.9 dB and a range resolution of 1.3 cm, simultaneously accommodating a data transmission of 6 Gbit/s. In addition, the effect of embedding symbols on sensing metrics is also discussed, and by comparing the range solution and PSLR with various data rates, around $\sim$ 6 dB gain in the PSLR without any deterioration of range resolution is observed.
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| 25. |
- Lyu, Zhidong, et al.
(author)
-
Radar-Centric Photonic Terahertz Integrated Sensing and Communication System Based on LFM-PSK Waveform
- 2023
-
In: IEEE transactions on microwave theory and techniques. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9480 .- 1557-9670. ; 71:11, s. 5019-5027
-
Journal article (peer-reviewed)abstract
- The radar-centric terahertz integrated sensing and communication (THz-ISAC) is identified as a significant application in future wireless access networks. Up to date, previously reported demonstrations regarding radar sensing performance lack sufficient support in a complex environment with a strong target masking effect. This work tacks this problem by proposing a radar-centric waveform combining linear frequency modulation (LFM) waveform and phase shift keying (PSK). We first derive sensing metrics of the LFM-PSK waveform through theoretical analysis, including range resolution, peak sidelobe ratio (PSLR), and Cramér-Rao lower bound (CRLB). Then a proof-of-concept experiment on a photonics-assisted integrated sensing and communication (ISAC) system operating at 330 with 18 GHz bandwidth is conducted to verify the performance of the proposed LFM-PSK waveform. In the experiment, the proposed waveform can reach a PSLR of up to 20.9 dB and a range resolution of 1.3 cm, simultaneously accommodating a data transmission of 6 Gbit/s. In addition, the effect of embedding symbols on sensing metrics is also discussed, and by comparing the range solution and PSLR with various data rates, around ∼ 6 dB gain in the PSLR without any deterioration of range resolution is observed.
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| 26. |
- Pang, Xiaodan, Dr., et al.
(author)
-
Key technologies to enable terabit-scale digital radio-over-fiber systems
- 2019
-
In: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE. - 9781510625327
-
Conference paper (peer-reviewed)abstract
- With the approach of the 5G era, stringent requirements are imposed on the data transport solutions, including both of the supported transmission reach and the capacity. Radio-over-fiber technologies are considered to be promising candidates to cope with both aspects, owing to the low-loss and broad-bandwidth nature of the optical fibers. Meanwhile with such optical transport solutions, signals can be collected from the distributed remote radio sites and processed in a centralized manner. In this report, we target on the digital radio-over-fiber systems, and discuss about several key technologies, focusing on the aspects of coding and transmission, which could potentially enable terabit-scale data transport.
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| 27. |
- Wang, Shiwei, et al.
(author)
-
26.8-m THz wireless transmission of probabilistic shaping 16-QAM-OFDM signals
- 2020
-
In: APL Photonics.. - : AIP Publishing. - 2378-0967. ; 5:5
-
Journal article (peer-reviewed)abstract
- Recently, remarkable efforts have been made in developing wireless communication systems at ultrahigh data rates, with radio frequency (RF) carriers in the millimeter wave (30-300 GHz) and/or in the terahertz (THz, >300 GHz) bands. Converged technologies combining both the electronics and the photonics show great potential to provide feasible solutions with superior performance compared to conventional RF technologies. However, technical challenges remain to be overcome in order to support high data rates with considerably feasible wireless distances for practical applications, particularly in the THz region. In this work, we present an experimental demonstration of a single-channel THz radio-over-fiber (RoF) system operating at 350 GHz, achieving beyond 100 Gbit/s data rate over a 10-km fiber plus a >20-m wireless link, without using any THz amplifiers. This achievement is enabled by using an orthogonal frequency division multiplexing signal with a probabilistic-shaped 16-ary quadrature amplitude modulation format, a pair of highly directive Cassegrain antennas, and advanced digital signal processing techniques. This work pushes the THz RoF technology one step closer to ultrahigh-speed indoor wireless applications and serves as an essential segment of the converged fiber-wireless access networks in the beyond 5G era.
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| 28. |
- Wu, Zhihong, et al.
(author)
-
Increased osteopontin expression is associated with progression from vulvar precancerous lesions to vulvar squamous cell carcinoma
- 2014
-
In: Archives of Gynecology and Obstetrics. - Berlin : Springer. - 0932-0067 .- 1432-0711. ; 289:3, s. 637-644
-
Journal article (peer-reviewed)abstract
- Vulvar squamous cell carcinoma (VSCC) contributes to about 3-5 % of all gynecological cancers. Vulvar intraepithelial neoplasia (VIN) and vulvar lichen sclerosus (VLS) are regarded as precancerous lesions. Early detection and treatment of precancerous lesions may prevent development of VSCC. Osteopontin (OPN) has been shown to be involved in many physiological and pathological processes, such as tumor progression, by promoting cancer cell invasion and metastasis. As a result of these findings, OPN has been described as a potential marker for tumor progression in some malignancies. In this study, we investigated the expression of OPN in vulvar tissue specimens and compared its expression between different histopathological grades. In the present study, the expression patterns of OPN in 80 paraffin-embedded tissue specimens, including 25 VSCC samples, 21 VIN lesions and 21 VLS, in addition to 13 normal vulvar samples, were examined by the immunohistochemical method and chromogenic in situ hybridization. The intensity of OPN expression steadily increased according to the pathological grades. In addition, OPN staining was found in the extracellular matrix in VSCC. Expression levels of OPN increased from VLS and VIN to VSCC, and steadily increased with the pathological stage of VSCC. Our results suggest that OPN may be associated with the progression of VSCC.
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| 29. |
- Yu, X., et al.
(author)
-
Photonics-Aided 300–500 GHz Wireless Communications Beyond 100 Gbps
- 2022
-
In: THz Communications. - Cham : Springer Science and Business Media Deutschland GmbH. ; , s. 467-472
-
Book chapter (peer-reviewed)abstract
- We experimentally demonstrated a series of photonics-wireless transmissions in the 300–500 GHz band at the Technical University of Denmark (DTU) and the Zhejiang University (ZJU), with special efforts to drive the data rates beyond 100 Gbps and to extend the THz wireless reach by combining the techniques of state-of-the-art optoelectronic THz devices, spectrally efficient modulation formats and advanced digital signal processing.
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| 30. |
- Zhang, Ben, et al.
(author)
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Rapid solidification for green-solvent-processed large-area organic solar modules with >16% efficiency
- 2024
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In: Energy & Environmental Science. - : ROYAL SOC CHEMISTRY. - 1754-5692 .- 1754-5706.
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Journal article (peer-reviewed)abstract
- Enabling green-solvent-processed large-area organic solar cells (OSCs) is of great significance to their industrialization. However, precisely controlling the temperature-dependent fluid mechanics and evaporation behavior of green solvents with high-boiling points is challenging. Controlling these parameters is essential to prevent the non-uniform distribution of active layer components and severe molecule aggregation, which collectively degrade the power conversion efficiency (PCE) of large-scale devices. In this study, we revealed that the temperature gradient distribution across a wet film is the root of the notorious Marangoni effect, which leads to the formation of a severely non-uniform active layer on a large scale. Thus, a rapid solidification strategy was proposed to accelerate the evaporation of toluene, a green solvent, at room temperature. This strategy simultaneously inhibits the Marangoni effect and suppresses molecular aggregation in the wet film, allowing the formation of a nano-scale phase separation active layer with uniform morphology. The resultant toluene-processed 15.64-cm2 large-area OSC module achieves an outstanding PCE of 16.03% (certified: 15.69%), which represents the highest reported PCE of green-solvent-processed OSC modules. Notably, this strategy also exhibits a weak scale dependence on the PCE, and we successfully achieved a state-of-the-art PCE of 14.45% for a 72.00-cm2 OSC module. A rapid solidification strategy was developed for simultaneously avoiding the Marangoni effect and suppressing molecular aggregation. The resultant 15.64 cm2 large-area OSC module exhibited a record power conversion efficiency of 16.03%.
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| 31. |
- Zhang, H., et al.
(author)
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30 m 64-QAM multicarrier photonic-wireless communication link in the 300 GHz band
- 2022
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In: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE. - 9781510661264
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Conference paper (peer-reviewed)abstract
- In recent years, terahertz communication has attracted extensive attentions due to its large bandwidth for supporting terabit-per-second capacity. Along with the rapid evolution of terahertz optoelectronic devices, remarkable achievements have been witnessed in developing photonic terahertz communication systems with large capacities. In fact, photonics-assisted terahertz communication systems have exhibited some advantages, for instance, bridging a seamless connection between the existing optical fiber network and wireless network, offering flexible carrier switching over a wide radio frequency range, as well as supporting easy implementation of high-order complex modulation formats and multicarrier multiplexing terahertz channels. However, due to high atmospheric propagation loss, limited terahertz component bandwidth and low terahertz emission power, achieving simultaneous transmission of single-lane data rates beyond 200 Gbps is still challenging based on a single pair of terahertz transceivers. In this work, by employing subcarrier (SC) multiplexing, high-order 64-ary quadrature amplitude modulation (64-QAM) format, well-defined digital signal processing (DSP) and wideband terahertz transceivers, a multicarrier terahertz photonic-wireless communication link operating in the 300 GHz band is proposed and experimentally demonstrated. At the transmitter side, a baseband pseudo-random binary sequence (PRBS-15) signal with a baud rate of 12 Gbaud is generated from an arbitrary waveform generator (AWG), and then modulated onto an optical carrier centered at 193.414 THz. The modulated optical signal is combined with three optical carriers centered at 193.7035 THz, 193.7165 THz, and 193.7295 THz, for multi-carrier THz generation at a uni-traveling carrier photodiode (UTC-PD) featuring large bandwidth (100 GHz), which consists of three SCs centered at 286.5 GHz, 299.5 GHz and 312.5 GHz, respectively. At the receiver side, we employ a Schottky diode mixer with high sensitivity to down-convert the three terahertz SCs into the intermediate frequency (IF) domain, with three IF signals cantered at 6.5 GHz, 19.5 GHz, and 32.5 GHz, respectively, which are then processed using home-made advanced DSP routine, including a linear adaptive equalizer, compensation algorithms of frequency offset and phase noise. In the experiment, a total line data rate of 216 Gbps (72 Gbps/SC ×3 SC) over a wireless distance of 30 m is successfully transmitted, and the performance of all three SCs can reach below the hard decision forward-error-correction (HD-FEC) with 6.25 % overhead, reaching an aggregated net transmission capacity of up to 202.5 Gbps. This achievement of single-lane simultaneous transmission of beyond 200 Gbps using a single pair of 300 GHz transceivers is considered a significant step towards next-generation wireless communications.
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| 32. |
- Zhang, H., et al.
(author)
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Single-lane 200 Gbit/s photonic wireless transmission of multicarrier 64-QAM signals at 300 GHz over 30 m
- 2023
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In: Chinese Optics Letters (COL). - : Optica Publishing Group (formerly OSA). - 1671-7694. ; 21:2
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Journal article (peer-reviewed)abstract
- Recently, wireless communication capacity has been witnessing unprecedented growth. Benefits from the optoelectronic components with large bandwidth, photonics-assisted terahertz (THz) communication links have been extensively developed to accommodate the upcoming wireless transmission with a high data rate. However, limited by the available signal-to-noise ratio and THz component bandwidth, single-lane transmission of beyond 100 Gbit/s data rate using a single pair of THz transceivers is still very challenging. In this study, a multicarrier THz photonic wireless communication link in the 300 GHz band is proposed and experimentally demonstrated. Enabled by subcarrier multiplexing, spectrally efficient modulation format, well-tailored digital signal processing routine, and broadband THz transceivers, a line rate of 72 Gbit/s over a wireless distance of 30 m is successfully demonstrated, resulting in a total net transmission capacity of up to 202.5 Gbit/s. The single-lane transmission of beyond 200 Gbit/s overall data rate with a single pair of transceivers at 300 GHz is considered a significant step toward a viable photonics-assisted solution for the next-generation information and communication technology (ICT) infrastructure.
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| 33. |
- Zhang, Jiahao, et al.
(author)
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Analysis and Compensation of Nonlinear Dynamics in Optical Fiber Transmission with the Optoelectronic Reservoir Computing
- 2023
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In: Photonics Global Conference, PGC 2023. - : Institute of Electrical and Electronics Engineers (IEEE). ; , s. 12-16
-
Conference paper (peer-reviewed)abstract
- Optical fiber communication systems play an important role in broadband signal transmissions, where the nonlinear dynamics in the long-haul optical fiber transmissions greatly degrade the transmission performance and limit the fiber capacity and reach. This paper analyzes and compensates for the nonlinear dynamics in the long-haul optical fiber transmission with the delay-based optoelectronic reservoir computing (RC) scheme, which provides benefits like time-adaptive tracking, low-complexity and hardware implementation potentials. The generalization of the analysis and compensation schemes from the traditional amplitude-modulated PAM signal to the amplitude-phase-modulated QAM signal is achieved by signal preprocessing. In the numerical study, the proposed RC-based fiber dynamics compensation scheme, with fiber reach from 1400km to 3000km, shows considerable performance with the digital backpropagation scheme, which is always used as the benchmark for nonlinear compensation of long-haul fiber transmissions. The realization complexity is much reduced with the RC-based schemes, which has provided a new dawn for optics-based nonlinear analysis and compensations.
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| 34. |
- Zhang, Lu, et al.
(author)
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Hybrid fiber–THz fronthaul supporting up to 16384-QAM-OFDM with the delta-sigma modulation
- 2022
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In: Optics Letters. - : Optica Publishing Group (formerly OSA). - 0146-9592 .- 1539-4794. ; 47:17, s. 4307-4310
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Journal article (peer-reviewed)abstract
- With the progress of high-capacity radio access networks, ultra-dense small cells are rapidly being deployed in urban areas. As a result, the deployment of a large number of optical fibers in urban areas becomes a severe issue. In this Letter, we propose a hybrid fiber–terahertz (THz) mobile fronthaul system supporting flexible and high-order wireless signal transmission with the delta-sigma modulation. The photonic THz transmission is used as the seamless extension of fiber-based fronthaul in small cells. A 20-Gbit/s digital fiber–THz fronthaul system is experimentally demonstrated to validate the proposed scheme, with 10-km optical fiber transmission and 300-GHz wireless relay. Carrier aggregation of up to 10 40-MHz and 60-MHz 5G-new radio (5G-NR) channels at the radio carrier frequency of 3.9 GHz is reported. The design of quantization noise suppressed delta-sigma modulation enables the system to transmit orthogonal frequency division multiplexing (OFDM) modulation up to 16384 order quadrate amplitude modulation (QAM) mapping with the error vector magnitude (EVM) below 0.5%.
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| 35. |
- Zhang, Lu, et al.
(author)
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Nonlinearity-aware 200 Gbit/s DMT transmission for C-band short-reach optical interconnects with a single packaged electro-absorption modulated laser
- 2018
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In: Optics Letters. - : OPTICAL SOC AMER. - 0146-9592 .- 1539-4794. ; 43:2, s. 182-185
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Journal article (peer-reviewed)abstract
- We experimentally demonstrate the transmission of a 200 Gbit/s discrete multitone (DMT) at the soft forward error correction limit in an intensity-modulation direct-detection system with a single C-band packaged distributed feedback laser and traveling-wave electro absorption modulator (DFB-TWEAM), digital-to-analog converter and photodiode. The bit-power loaded DMT signal is transmitted over 1.6 km standard single-mode fiber with a net rate of 166.7 Gbit/s, achieving an effective electrical spectrum efficiency of 4.93 bit/s/Hz. Meanwhile, net rates of 174.2 Gbit/s and 179.5 Gbit/s are also demonstrated over 0.8 km SSMF and in an optical back-to-back case, respectively. The feature of the packaged DFB-TWEAM is presented. The nonlinearity-aware digital signal processing algorithm for channel equalization is mathematically described, which improves the signal-to-noise ratio up to 3.5 dB.
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| 36. |
- Zhang, L., et al.
(author)
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Quantum Noise Secured Terahertz Communications
- 2023
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In: IEEE Journal of Selected Topics in Quantum Electronics. - : Institute of Electrical and Electronics Engineers Inc.. - 1077-260X .- 1558-4542. ; 29:5
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Journal article (peer-reviewed)abstract
- The terahertz communications display an important role in high-speed wireless communications, the security threat from the eavesdroppers in the terahertz communications has been gaining attention recently. The true randomness in the physical layer can ensure one-time-pad encryption for secured terahertz communications, however, physical layer security schemes like the quantum key distribution methods suffer from device imperfections that limit the desirable signal rate and link distance. Herein, we present the quantum noise secured terahertz wireless communications with photonic terahertz signal generation schemes. With the high-order diffusion algorithms, the signal is masked by the quantum noise ciphers to the eavesdroppers and cannot be detected because the inevitable randomness by quantum noise measurement will cause physical measurement errors. In the experiment, we demonstrate 16 Gbits-1 quantum noise secured terahertz wireless communications with the conventional optical communication realms and devices, operating at 300 GHz terahertz frequency. This quantum noise secured terahertz communication approach is a significant step toward high-security wireless communications.
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| 37. |
- Zhang, Yuan, et al.
(author)
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Quantitative Proteomics of TRAMP Mice Combined with Bioinformatics Analysis Reveals That PDGF-B Regulatory Network Plays a Key Role in Prostate Cancer Progression
- 2018
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In: Journal of Proteome Research. - : American Chemical Society (ACS). - 1535-3893 .- 1535-3907. ; 17:7, s. 2401-2411
-
Journal article (peer-reviewed)abstract
- Transgenic adenocarcinoma of the mouse prostate (TRAMP) mice is a widely used transgenic animal model of prostate cancer (PCa). We performed a label-free quantitative proteomics analysis combined with a bioinformatics analysis on the entire prostate protein extraction from TRAMP mice and compared it with WT littermates. From 2379 total identified proteins, we presented a modest mice prostate reference proteome containing 919 proteins. 61 proteins presented a significant expression difference between two groups. The integrative bioinformatics analysis predicted the overexpression of platelet-derived growth factor B (PDGF-B) in tumor tissues and supports the hypothesis of the PDGF-B signaling network as a key upstream regulator in PCa progression. Furthermore, we demonstrated that Crenolanib, a novel PDGF receptor inhibitor, inhibited PCa cell proliferation in a dose-dependent manner. Finally, we revealed the importance of PDGF-B regulatory network in PCa progression, which will assist us in understanding the role and mechanisms of PDGF-B in promoting cancer growth and provide valuable knowledge for future research on anti-PDGF therapy.
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| 38. |
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| 39. |
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| 40. |
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| 41. |
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| 42. |
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| 43. |
- Dimitrios, Nikas, et al.
(author)
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Evaluation of local strength via microstructural quantification in a pearlitic rail steel deformed by simultaneous compression and torsion
- 2018
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In: Materials Science & Engineering. - : Elsevier. - 0921-5093 .- 1873-4936. ; 737, s. 341-347
-
Journal article (peer-reviewed)abstract
- Pearlitic steels are commonly used for railway rails because they combine good strength and wear properties. During service, the passage of trains results in large accumulation of shear strains in the surface layer of the rail, sometimes leading to crack initiation. Knowledge of the material properties versus the shear strain in this layer is therefore important for fatigue life predictions. In this study, fully pearlitic R260 rail steel was deformed using a bi-axial torsion-compression machine to reach different shear strains. Microstructural parameters including interlamellar spacing, thickness of ferrite and cementite lamellae and dislocation density in the ferrite lamellae, as well as hardness were quantitatively characterized at different shear strain levels. Based on the microstructural observations and the quantification of the microstructural parameters, the local flow stresses were estimated based on boundary strengthening and dislocation strengthening models. A good agreement was found between the estimated flow stresses and the flow stresses determined from microhardness measurements. d
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| 44. |
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| 45. |
- Fan, Yuchuan, et al.
(author)
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A Comparison of Linear Regression and Deep Learning Model for EVM Estimation in Coherent Optical Systems
- 2022
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In: 2022 Conference on Lasers and Electro-Optics Pacific Rim, CLEO-PR 2022 - Proceedings. - : Institute of Electrical and Electronics Engineers (IEEE).
-
Conference paper (peer-reviewed)abstract
- We experimentally investigate EVM estimation approaches based on linear regression and deep learning for 28 Gbaud coherent optical systems. We show that the estimation performances are comparable when the modulation format is known.
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| 46. |
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| 47. |
- Fan, Yuchuan, et al.
(author)
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EVM Estimation for Performance Monitoring in Coherent Optical Systems : An Approach of Linear Regression
- 2022
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In: Optics InfoBase Conference Papers. - : Optica Publishing Group (formerly OSA). - 9781557528209
-
Conference paper (peer-reviewed)abstract
- We experimentally demonstrate the effectiveness of a simple linear regression scheme for optical performance monitoring when applied after modulation format identification. It outperforms the FFNN-based benchmark scheme providing 0.2% mean absolute error for EVM estimation., © 2022 The Author(s)
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| 48. |
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| 49. |
- Fan, Yuchuan, et al.
(author)
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Feedforward Neural Network-Based EVM Estimation : Impairment Tolerance in Coherent Optical Systems
- 2022
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In: IEEE Journal of Selected Topics in Quantum Electronics. - : Institute of Electrical and Electronics Engineers Inc.. - 1077-260X .- 1558-4542. ; 28:4
-
Journal article (peer-reviewed)abstract
- Error vector magnitude (EVM) is commonly used for evaluating the quality of m-ary quadrature amplitude modulation (mQAM) signals. Recently proposed deep learning techniques for EVM estimation extend the functionality of conventional optical performance monitoring (OPM). In this article, we evaluate the tolerance of our developed EVM estimation scheme against various impairments in coherent optical systems. In particular, we analyze the signal quality monitoring capabilities in the presence of residual in-phase/quadrature (IQ) imbalance, fiber nonlinearity, and laser phase noise. We use feedforward neural networks (FFNNs) to extract the EVM information from amplitude histograms of 100 symbols per IQ cluster signal sequence captured before carrier phase recovery. We perform simulations of the considered impairments, along with an experimental investigation of the impact of laser phase noise. To investigate the tolerance of the EVM estimation scheme to each impairment type, we compare the accuracy for three training methods: 1) training without impairment, 2) training one model for all impairments, and 3) training an independent model for each impairment. Results indicate a good generalization of the proposed EVM estimation scheme, thus providing a valuable reference for developing next-generation intelligent OPM systems.
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| 50. |
- Fan, Yuchuan, et al.
(author)
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Linear Regression vs. Deep Learning for Signal Quality Monitoring in Coherent Optical Systems
- 2022
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In: IEEE Photonics Journal. - : Institute of Electrical and Electronics Engineers Inc.. - 1943-0655. ; 14:4
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Journal article (peer-reviewed)abstract
- Error vector magnitude (EVM) is a metric for assessing the quality of m-ary quadrature amplitude modulation (mQAM) signals. Recently proposed deep learning techniques, e.g., feedforward neural networks (FFNNs) -based EVM estimation scheme leverage fast signal quality monitoring in coherent optical communication systems. Such a scheme estimates EVM from amplitude histograms (AHs) of short signal sequences captured before carrier phase recovery (CPR). In this work, we explore further complexity reduction by proposing a simple linear regression (LR) -based EVM monitoring method. We systematically compare the performance of the proposed method with the FFNN-based scheme and demonstrate its capability to infer EVM from an AH when the modulation format information is known in advance. We perform both simulation and experiment to show that the LR-based EVM estimation method achieves a comparable accuracy as the FFNN-based scheme. The technique can be embedded with modulation format identification modules to provide comprehensive signal information. Therefore, this work paves the way to design a fast-learning scheme with parsimony as a future intelligent OPM enabler.
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