2015-920 A Single-Shot Network Analysis Method for the Characterization of Opto-Electronic and Electrical Devices and Systems

SUMMARY

UCLA researchers in the Department of Electrical Engineering have developed a single-shot network analysis method that can perform both time and frequency domain measurements of non-linear behavior of various optical or electrical devices and systems within significantly reduced test time.

BACKGROUND

A network analyzer measures the network parameters of active and passive components of optical and electrical devices. The ability to measure the input characteristics of each port, as well as the transfer characteristics between different ports of each component gives designers the knowledge to configure a component as part of a larger system.

There are two basic types of network analyzer: scalar network analyzer (SNA), which measures only amplitude-related properties; and vector network analyzer (VNA), which measures both amplitude- and phase-related properties. The growing demand for higher data bandwidth requires increase of the operating frequency of components and systems. It is challenging for conventional SNA and VNA, as well as time domain reflectometer (TDR) to perform accurate instrumentation and measurements of the various characteristics of electronic and optical devices or systems at high data bandwidth.

There are two types of high-performance digital oscilloscopes to reconstruct incoming signal digitally: real time (RT) oscilloscope digitizes the full wideband signal with high throughput at the cost of reduced resolution, limited bandwidth, massive energy consumption, larger footprint, and higher price; and equivalent time (ET) oscilloscope samples incoming repetitive signals at a rate significantly lower than the Nyquist, but can reconstruct repetitive signals by accumulating samples over many periods. ET oscilloscopes have excellent resolution, jitter performance, and high bandwidth capabilities, but are limited to analyzing repetitive signals with low throughput. ET oscilloscopes also require a synchronized clock and long data acquisition and analyzing time. It is also difficult and time-consuming for these analyzers to perform certain measurements such as non-linear system transfer function analysis.

Therefore, we need real-time wideband network analyzers that can perform measurements and modeling with both amplitude and phase, as well as in time domain over a wide frequency range within reasonable test time.

INNOVATION

Researchers at UCLA have developed a single-shot network analysis (SiNA) method, which uses photonic time-stretch technique to compress the signal bandwidth to a more manageable rate before digitization. Combining its real-time burst sampling modality based on time-stretch enhanced recording (TiSER) oscilloscope, this method can be used to study non-linear behavior of various optical or electrical devices and systems, as well as high-speed dynamics of high-speed circuits and systems.

APPLICATIONS

• Characterizing RF, microwave, and optical devices or systems
• Wireless communication (i.e. base transceiver station, P2P communication, consumer electronics)
• Aerospace and defense (i.e. satellite ground station, radar, military communication)
• Medical and industrial process (i.e. diagnosis system)
• Science (i.e. particle accelerator, X-ray-free electron laser systems, time resolved fluorescence microscopy)

ADVANTAGES

• Boosts the performance of the analog-to-digital converter (ADC) and digital signal processing (DSP), and the time-stretch architecture scales with ADC and DSP technology
• Improves in resolution and speed as the electronic backend technology progresses

Table 1 lists several of the advantages of SiNA in comparison with a commercial vector network analyzer.

RELATED MATERIAL

• Buckley, B. W., Fard, A., & Jalali, B. (2011). Time-Stretch Analog-to-Digital Conversion Using Phase Modulation and Broadband Balanced Coherent Detection for Improving Resolution. In Optical Fiber Communication Conference/National Fiber Optic Engineers Conference 2011 (p. OThW4). Washington, D.C.: OSA. http://doi.org/10.1364/OFC.2011.OThW4.
• Motafakker-Fard, A., Gupta, S., & Jalali, B. (2010). Digital Equalization of Ultrafast Data Using Real-Time Burst Sampling. In Optical Fiber Communication Conference (p. OTuN3). Washington, D.C.: OSA. http://doi.org/10.1364/OFC.2010.OTuN3.
• Fard, A., Buckley, B., & Jalali, B. (2010). Doubling the Spectral Efficiency of Photonic Time-Stretch Analog-to-Digital Converter by Polarization Multiplexing. In Frontiers in Optics 2010/Laser Science XXVI (p. FThI3). Washington, D.C.: OSA. http://doi.org/10.1364/FIO.2010.FThI3.
• Fard, A., Yang, J.-Y., Buckley, B., Wang, J., Chitgarha, M. R., Zhang, L., … Jalali, B. (2011). 100-Gb/s RZ-DQPSK Signal Monitoring Using Time-stretch Enhanced Recording Oscilloscope. In CLEO:2011 - Laser Applications to Photonic Applications (p. CFP1). Washington, D.C.: OSA. http://doi.org/10.1364/CLEO_SI.2011.CFP1.

• Fard, A., Buckley, B., & Jalali, B. (2011). Spectral Efficiency Improvement in Photonic Time-Stretch Analog-to-Digital Converter via Polarization Multiplexing. IEEE Photonics Technology Letters, 23(14), 947–949. http://doi.org/10.1109/LPT.2011.2142414.
• Fard, A., Yang, J.-Y., Buckley, B., Wang, J., Chitgarha, M. R., Zhang, L., … Jalali, B. (2011). Time-stretch oscilloscope with dual-channel differential detection front end for monitoring of 100 Gb/s return-to-zero differential quadrature phase-shift keying data. Optics Letters, 36(19), 3804–6. http://doi.org/10.1364/OL.36.003804.
• Buckley, B. W., Madni, A. M., & Jalali, B. (2013). Coherent time-stretch transformation for real-time capture of wideband signals. Optics Express, 21(18), 21618–27. http://doi.org/10.1364/OE.21.021618.
• Fard, A. M., Buckley, B., Zlatanovic, S., Brès, C.-S., Radic, S., & Jalali, B. (2012). All-optical time-stretch digitizer. Applied Physics Letters, 101(5), 051113. http://doi.org/10.1063/1.4742173.
• Gupta, S., & Jalali, B. (2009). Time stretch enhanced recording oscilloscope. Applied Physics Letters, 94(4), 041105. http://doi.org/10.1063/1.3075057.
• Fard, A. M., Gupta, S., & Jalali, B. (2013). Photonic time-stretch digitizer and its extension to real-time spectroscopy and imaging. Laser & Photonics Reviews, 7(2), 207–263. http://doi.org/10.1002/lpor.201200015.

STATUS OF DEVELOPMENT

PUBLISHED INTERNATIONAL APPLICATION       WO2017223149       08/18/2020