Photonic Integrated Circuits for Communication Systems

RADIOENGINEERING, VOL. 27, NO. 2, JUNE 2018 357 Photonic Integrated Circuits for Communication Systems Jozef CHOVAN 1, 3, František UHEREK 1, 2 1 2 International Laser Centre, Ilkovičova 3, 841 04 Bratislava, Slovakia Faculty of Electrical Engineering and Information Technology, Slovak University of Technology, Ilkovičova 3, 812 19 Bratislava, Slovakia 3 OptoNet Slovakia, s.r.o., Detvianska Huta 215, 96205 Hriňová , Submitted April 30, 2018 / Accepted April 30, 2018 Abstract. Photonic Integrated Circuits allow to meet the increasing demand of communication systems for internet which is growing at about 40% per year. This growth is driven mainly by increasing video traffic in the internet network. This growth is now further accelerated by mobile access, with video clients shipping on all smart phones and tablets, enabling video to be consumed more conveniently via network connections anywhere and anytime. This paper reviews several material platform of photonic integrated circuits and compares their performance. This paper also describes the new approaches in the design and fabrication of optical transceivers based on photonic integrated circuits for next terabit era. Keywords Integrated photonics, photonics integrated circuit, optoelectronics, optical transport network 1. Introduction The development of optical transport network technology is stimulated by the emerging services such as data center cloud interconnection services, ultra-bandwidth video services, and 5G mobile network services will drive future optical communications industry development and architecture transformation. crease to 48 GB by the end of 2023. Western Europe has the second highest usage, with traffic set to reach 4.1 GB by the end of 2017 and 28 GB by the end of 2023. Western Europe will be the region with the highest growth rate in monthly mobile data traffic per smartphone during the forecast period. The high average usage in India – estimated to reach 3.9 GB per month per smartphone at the end of 2017 – is mainly due to an introductory LTE offer by an operator during the latter half of 2016, which included free voice and data traffic. Data traffic is expected to continue to grow, reaching 18 GB per month per smartphone in 2023 [1]. Factors that will drive higher usage in general include an increase in the number of LTE subscriptions, improved device capabilities and more affordable data plans, as well as an increase in data-intensive content. As virtual reality and augmented reality technologies are more widely adopted, content will become even more data-intensive. Total mobile data traffic is expected to rise at a compound annual growth rate of 42 percent. Total mobile data traffic for all devices is anticipated to increase by 8 times during the forecast period, reaching around 110 EB per month by the end of 2023. At close to 85 percent, data traffic generated by smartphones is already accounting for the largest proportion of mobile data traffic. Going forward, smartphone data traffic will become even more dominant, and is expected to increase by 9 times during the forecast period to account for close to 95 percent of the total mobile data traffic by the end of 2023 [1]. A number of different industry surveys indicate that total internet demand is growing at about 40% per year. This growth is driven mainly by increasing video traffic in the network—Netflix now takes up to 30% of the internet’s bandwidth at peak hours and new competitors like Amazon, Hulu, Youku, and the BBC iPlayer are growing rapidly. This growth is now further accelerated by mobile access, with video clients shipping on all smart phones and tablets, enabling video to be consumed more conveniently via network connections anywhere, anytime. Monthly mobile data traffic per smartphone continues to increase in all regions. North America has the highest usage, and traffic is expected to reach 7.1 GigaBytes (GB) per month per smartphone by the end of 2017 and to in- DOI: 10.13164/re.2018.0357 Fig. 1. Data traffic pre active smartphones in Gigabytes per month [1]. FEATURE ARTICLE 358 J. CHOVAN, F. UHEREK, PHOTONIC INTEGRATED CIRCUITS FOR COMMUNICATION SYSTEMS Fig. 2. The 2018 Ethernet Roadmap made by The Ethernet Alliance [2]. and interoperability and the bandwidth demand of connected cards could be the next big driver for Ethernet to go beyond 400 GbE [2]. Enterprise and campus applications drive the bulk of Ethernet port shipments with hundreds of millions of ports shipping per year. Ethernet's roots are in enterprise local area networks (LANs) where the entire Ethernet family, including the BASE-T products, can be found, LANs are rich in copper where over 70 Billion meters of cable have been deployed over the past 15 years. Enterprise data centers are very cost sensitive and most servers deploy GbE and 10 GbE [2]. Fig. 3. The past, present and future of Ethernet speeds [2]. The Ethernet Alliance’s new roadmap traces Ethernet’s path from 10 Mb/s through present-day speeds of 1 to 400 gigabit Ethernet (GbE), and looks ahead to future speeds achieving up to 1.6 terabits (TbE) and beyond (Fig. 2). Fig. 3 shows the evolution of the Ethernet speeds and possible future speeds [2]. The forward-looking map also provides guidance into key underlying technologies, current and future interfaces, and the numerous application spaces where Ethernet plays a fundamental role [2]. Building and industrial applications highlight the need for lower speed Ethernet solutions in harsh environments The Ethernet community is working to define a single standard for 10 Mb/s operation plus power delivery over a single twisted pair. This will consolidate a landscape of multiple legacy protocols, driving the promise of Ethernet's mufti-level interoperability to new heights for these spaces, as 2019 forecasts point to 165 million ports per year [2]. Automotive Ethernet is one of Ethernet's latest success stones. Forecasts predict up to 500 million ports of Ethernet will ship in 119 million vehicles by 2019. Ethernet links within cars provide data and power to reduce the cost and weight in vehicles while providing economies of scale Cloud providers were the first to adopt 10 GbE servers on a large scale in 2010 for hyperscale data centers. With voracious appetites for east-west traffic, hyperscale servers have moved to 25 GbE today and will move to 50 GbE by the end of 2018. Unique networking architectures within these warehouse scale data centers have driven multiple multimode and single-mode fiber solutions at 100, 200 and 400 GbE. The bandwidth demands of hyperscale data centers and service providers continue to grow exponentially and in a similar direction that blurs the lines between the two [2]. Service providers have driven higher speed Ethernet solutions for decades. Router connections, client side optics for optical transport networks (OTN) equipment, and wireless backhaul have continually pushed Ethernet to higher rates and dis (...truncated)