Visible to the public Biblio

Filters: Keyword is optical modulation  [Clear All Filters]
2021-01-25
Guri, M..  2020.  CD-LEAK: Leaking Secrets from Audioless Air-Gapped Computers Using Covert Acoustic Signals from CD/DVD Drives. 2020 IEEE 44th Annual Computers, Software, and Applications Conference (COMPSAC). :808—816.

Air-gapped networks are isolated from the Internet, since they store and process sensitive information. It has been shown that attackers can exfiltrate data from air-gapped networks by sending acoustic signals generated by computer speakers, however this type of covert channel relies on the existence of loudspeakers in the air-gapped environment. In this paper, we present CD-LEAK - a novel acoustic covert channel that works in constrained environments where loudspeakers are not available to the attacker. Malware installed on a compromised computer can maliciously generate acoustic signals via the optical CD/DVD drives. Binary information can then be modulated over the acoustic signals and be picked up by a nearby Internet connected receiver (e.g., a workstation, hidden microphone, smartphone, laptop, etc.). We examine CD/DVD drives and discuss their acoustical characteristics. We also present signal generation and detection, and data modulation and demodulation algorithms. Based on our proposed method, we developed a transmitter and receiver for PCs and smartphones, and provide the design and implementation details. We examine the channel and evaluate it on various optical drives. We also provide a set of countermeasures against this threat - which has been overlooked.

2020-07-13
Ge, Hong, Dai, Jianxin, Huang, Bo, Wang, Jin-Yuan.  2019.  Secrecy Rate Analysis for Visible Light Communications Using Spatial Modulation. 2019 IEEE 21st International Conference on High Performance Computing and Communications; IEEE 17th International Conference on Smart City; IEEE 5th International Conference on Data Science and Systems (HPCC/SmartCity/DSS). :1241–1248.
This paper mainly investigates the physical layer security for visible light communication (VLC) based on spatial modulation (SM). The indoor VLC system includes multiple transmitters, a legitimate receiver and an eavesdropper. In the system, we consider two constraints of the input signal: non-negative and dimmable average optical intensity constraints. According to the principle of information theory and the spatial modulation scheme of uniform selection (US), the upper and the lower bounds on the secrecy rate for SM based VLC are derived, respectively. Numerical results show that the performance gap between the upper and lower bounds of the secrecy rate is small and relatively close, which indicates that the derived secrecy rate bounds can be used to evaluate the system performance. Moreover, when the number of transmitters is set to be one, the spatial modulation disappears, and the secrecy rate bounds in this paper are consistent with the existing results. To further improve the secrecy performance, a channel adaptive selection (CAS) scheme is proposed for selecting the active transmitter. Numerical result indicates that the CAS scheme has better performance than the US scheme.
2020-06-19
Maeda, Hideki, Kawahara, Hiroki, Saito, Kohei, Seki, Takeshi, Kani, Junichi.  2019.  Performance Degradation of SD-FEC Due to XPM Phase Noise in WDM Transmission System with Low-Speed Optical Supervisory Channel. 2019 IEEE Photonics Conference (IPC). :1—2.

An experiment and numerical simulations analyze low-speed OSC derived XPM-induced phase noise penalty in 100-Gbps WDM systems. WDM transmission performance exhibits signal bit-pattern dependence on OSC, which is due to deterioration in SD-FEC performance.

Tanizawa, Ken, Futami, Fumio.  2019.  Digital Coherent 20-Gbit/s DP-PSK Y-00 Quantum Stream Cipher Transmission over 800-km SSMF. 2019 Optical Fiber Communications Conference and Exhibition (OFC). :1—3.

We demonstrate secure fiber-optic transmission utilizing quantum-noise signal masking by 217-level random phase modulation. Masking of 157 signal phase levels at a BER of HD-FEC threshold is achieved without significant impacts on the transmission performance.

2018-11-19
Yildiz, O., Gulbahar, B..  2018.  FoVLC: Foveation Based Data Hiding in Display Transmitters for Visible Light Communications. 2018 14th International Wireless Communications Mobile Computing Conference (IWCMC). :629–635.

Visible light communications is an emerging architecture with unlicensed and huge bandwidth resources, security, and experimental implementations and standardization efforts. Display based transmitter and camera based receiver architectures are alternatives for device-to-device (D2D) and home area networking (HAN) systems by utilizing widely available TV, tablet and mobile phone screens as transmitters while commercially available cameras as receivers. Current architectures utilizing data hiding and unobtrusive steganography methods promise data transmission without user distraction on the screen. however, current architectures have challenges with the limited capability of data hiding in translucency or color shift based methods of hiding by uniformly distributing modulation throughout the screen and keeping eye discomfort at an acceptable level. In this article, foveation property of human visual system is utilized to define a novel modulation method denoted by FoVLC which adaptively improves data hiding capability throughout the screen based on the current eye focus point of viewer. Theoretical modeling of modulation and demodulation mechanisms hiding data in color shifts of pixel blocks is provided while experiments are performed for both FoVLC method and uniform data hiding denoted as conventional method. Experimental tests for the simple design as a proof of concept decreases average bit error rate (BER) to approximately half of the value obtained with the conventional method without user distraction while promising future efforts for optimizing block sizes and utilizing error correction codes.

2018-08-23
Keeler, G. A., Campione, S., Wood, M. G., Serkland, D. K., Parameswaran, S., Ihlefeld, J., Luk, T. S., Wendt, J. R., Geib, K. M..  2017.  Reducing optical confinement losses for fast, efficient nanophotonic modulators. 2017 IEEE Photonics Society Summer Topical Meeting Series (SUM). :201–202.

We demonstrate high-speed operation of ultracompact electroabsorption modulators based on epsilon-near-zero confinement in indium oxide (In$_\textrm2$$_\textrm3$\$) on silicon using field-effect carrier density tuning. Additionally, we discuss strategies to enhance modulator performance and reduce confinement-related losses by introducing high-mobility conducting oxides such as cadmium oxide (CdO).

2017-02-21
Y. Y. Won, D. S. Seo, S. M. Yoon.  2015.  "Improvement of transmission capacity of visible light access link using Bayesian compressive sensing". 2015 21st Asia-Pacific Conference on Communications (APCC). :449-453.

A technical method regarding to the improvement of transmission capacity of an optical wireless orthogonal frequency division multiplexing (OFDM) link based on a visible light emitting diode (LED) is proposed in this paper. An original OFDM signal, which is encoded by various multilevel digital modulations such as quadrature phase shift keying (QPSK), and quadrature amplitude modulation (QAM), is converted into a sparse one and then compressed using an adaptive sampling with inverse discrete cosine transform, while its error-free reconstruction is implemented using a L1-minimization based on a Bayesian compressive sensing (CS). In case of QPSK symbols, the transmission capacity of the optical wireless OFDM link was increased from 31.12 Mb/s to 51.87 Mb/s at the compression ratio of 40 %, while It was improved from 62.5 Mb/s to 78.13 Mb/s at the compression ratio of 20 % under the 16-QAM symbols in the error free wireless transmission (forward error correction limit: bit error rate of 10-3).

2015-05-06
Xiang Zhou.  2014.  Efficient Clock and Carrier Recovery Algorithms for Single-Carrier Coherent Optical Systems: A systematic review on challenges and recent progress. Signal Processing Magazine, IEEE. 31:35-45.

This article presents a systematic review on the challenges and recent progress of timing and carrier synchronization techniques for high-speed optical transmission systems using single-carrier-based coherent optical modulation formats.