R&D Activities of Radio-Over-Fiber Technology in NICT

R&D activities of radio-over-fiber technology in NICT

Toshiaki Kuri National Institute of Information and Communications Technology (NICT)

IMT-2020/5G Workshop and Demo Day (Geneva, Switzerland, July 11, 2017) 1 Acknowledgement

I would like to thank

Dr. Atsushi Kanno (NICT), Dr. Pham Tien Dat (NICT), Dr. Naokatsu Yamamoto (NICT), Dr. Toshimasa Umezawa (NICT), and Prof. Tetsuya Kawanishi (Waseda Univ./NICT).

Some resultants of the “Research and Development to Expand Radio Frequency Resources” project supported by the Ministry of Internal Affairs and Communications (MIC), Japan are included in this presentation.

1. What is Radio-over-Fiber (RoF)

2. R&D Examples of RoF technologies

3. Standardization activities of RoF

technologies at ITU-T SG15

4. Summary

[Ref.] A. Kanno, T. Kuri, and T. Kawanishi, “Radio wave transmission via an optical link,” NICT NEWS, no.432, pp.5-6, Sept. 2013. (http://nict.go.jp/en/data/nict-news/NICT_NEWS_1309_E.pdf) [Figure is modified.]

• Two features Applicable to Ø Preservation of waveform IMT-2020/5G Ø Tolerance to electro-magnetic interference systems the same waveform

RF signal Lightwave modulated by RF signal RF signal

Optical fiber

RF signal source E/O conversion O/E conversion

RF: radio frequency No interference from radio signal E/O: electrical-to-optical outside of fiber O/E: optical-to-electrical

[Ref.] ITU-T G-series Recommendations – Supplement 55 (07/2015), Radio-over-fibre (RoF) technologies and their applications (http://www.itu.int/rec/T-REC-G.Sup55-201507-I).

Copyright © National Institute of Information and Communications Technology All Rights Reserved. 5 R&D examples RoF transmission of an LTE signal over a typical optical distribution network (ODN) used in PON systems SNI S/R R/S UNI OLT ODN ONU E/O converter O/E converter f : 2.68 GHz RF λc: 1549.5 nm 25+5+10 km BW: 20 MHz BW: ≤3 GHz 0-30 dB BW: 1 nm BW: ≤3 GHz LTE VSG RoF Tx VOA EDFA OBPF RoF Rx LTE SA 3 cascaded LTE band #7 SMFs Splitting loss Auto-current EVM emulation control measurement Interconnection with RoF technology Radio signal 20 Remote radio generator head 10 0 Strong -10 0 dB candidate of -20 10 dB front-haul -30 No reach extender 20dB (No optical amplifier) 30 dB technologies Measured optical power [dBm] -40 [Ref.] ITU-T G-series Recommendations – Supplement 55 (07/2015), Radio-over-fibre (RoF) technologies and their applications (http://www.itu.int/rec/T-REC-G.Sup55-201507-I).

80 After 40-km SMF 20-MHz bandwidth QPSK 70 20-MHz bandwidth 16QAM 60 20-MHz bandwidth 64QAM N1 class 50 Also useful for ODN N2 class 40 classes E1 class microwave-band IMT-2020/5G 30 E2 class

EVM [%rms] systems 20 Required EVM for QPSK (17.5 [%rms]) Required EVM for 16QAM (12.5 [%rms]) 10 Required EVM for 64QAM (8 [%rms]) defined in the EVM for back-to-back: < 1 ITU-T G-series 0 Recs. of PON 0 10 20 30 40 50 60 systems Optical path loss [dB] [Ref.] ITU-T G-series Recommendations – Supplement 55 (07/2015), Radio-over-fibre (RoF) technologies and their applications (http://www.itu.int/rec/T-REC-G.Sup55-201507-I).

Optical technology Millimeter-wave-band Digital signal radio signal(s)

≥ 40 Gbit/s

Millimeter-wave Optical Direct optical- signal generator multi-level to-millimeter- Radio receiver w/ optical technol. modulator wave converter with digital signal processing ~ 100GHz High-speed digital signal processing

Optical frequency 16-QAM signal RoF technology

V-pol. H-pol. RF shield room

10 Gbaud

20 Gbaud 90-GHz wireless link Transceiver 20-Gbaud QPSK RoF signal generator Useful for future millimeter- wave-band and Optical fiber high-bit-rate Receiver 5G/B5G systems

Copyright © National Institute of Information and Communications Technology All Rights Reserved. 9 R&D examples Advanced wireless network for IMT-2020/5G systems ●High data rate : > 10 Gbps ●High capacity ●Low latency ●Low cost Macro-cell Small-cell Fibers Fiber BBU BBUs

RRH

Our developed key component for O/E conversion

●High O/E efficiency ●High output power

Over 100GHz responsivity with no bias

[Ref.] T. Umezawa, K. Kashima, A. Kanno, A. Matsumoto, K. Akahane, N. Yamamoto, and T. Kawanishi “100-GHz Fiber-Fed Optical-to-Radio Converter for Radio- and Power-Over-Fiber Transmission,” IEEE J. Selected Topics in Quantum Elec., vol.23, no.3, May/June 2017.

Copyright © National Institute of Information and Communications Technology All Rights Reserved. 10 R&D examples High-precision imaging technology using 90-GHz-band linear cells (Collaborative R&D project: FY2011- FY2015) Foreign object debris (FOD) detection system by using millimeter-wave-band frequency-modulated continuous-wave (FM-CW) signal Debris (FOD) Alert

Optical distribution network Millimeter-wave-band FM-CW signal RoF technology

Copyright © National Institute of Information and Communications Technology All Rights Reserved. 11 Standardization activities at ITU-T SG15 ITU-T G-series Recommendations – Supplement 55 (07/2015) Radio-over-fibre (RoF) technologies and their applications

Table of contents 1. Scope 2. References 3. Definitions 4. Abbreviations and acronyms 5. General concept 6. System architectures 7. Fundamental technologies 8. Network models 9. System design for supporting radio access system over optical access network Bibliography

[Ref.] ITU-T G-series Recommendations – Supplement 55 (07/2015), Radio-over-fibre (RoF) technologies and their applications (http://www.itu.int/rec/T-REC-G.Sup55-201507-I).

Copyright © National Institute of Information and Communications Technology All Rights Reserved. 12 Standardization activities at ITU-T SG15 Draft ITU-T G-series Recommendations Radio over fiber systems（G.RoF）（from July 2015） l Abstract（from draft version.0.6 (June 27, 2017)） This recommendation specifies radio over fiber transmission systems suitable for access network applications. l Scope（from draft version.0.6） This recommendation develops a new type of optical access network based on radio-over-fiber (RoF) technologies. In general, RoF technologies can be classified into two groups, analog RoF and digital RoF. The digital RoF requirements may be satisfied by elements of the G.989 series with necessary enhancements. The analog RoF system is currently unspecified in any other recommendation. The recommendation will include consideration of the common applications, the requirements that stem from these, the specification of the analog optical link and/or the necessary functions to digitally carry the radio signals over various optical access systems, the associated signal processing, and the management aspects of the systems. l Co-editors (Q2/15: SG15 Question 2 “optical systems for fibre access network”) Seung-Hyun CHO (ETRI), Toshiaki KURI (NICT), Yuanqiu LUO (Futurewei Tech. Inc.)

[Ref.] ITU-T SG15 (http://www.itu.int/ITU-T/workprog/wp_item.aspx?isn=10590)

• Overview of RoF technologies

• Introduction of some R&D examples ü RoF transmission of LTE signal over PON ODN ü RoF transmission of W-band signal ü Communication system application ü FM-CW radar system application

• Introduction of standardization activities at ITU-T SG15 ü G Suppl.55 “RoF technologies and their applications” ü G.RoF “RoF systems”