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Unit IV. Programming light on a chip 1. Study the following words and expressions.

Postdoctoral fellow – постдокторант (постдокторантура – в странах Западной Европы, Америки и в Австралии научное исследование, выполняемое учёным, недавно получившим степень PhD);

Harvard-spawned – при участии Гарвардского университета; ubiquitous – широкораспространенный, повсеместный.

2. Read and translate the text.

Researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have developed a new integrated photonics platform that can store light and electrically control its frequency (or color) in an integrated circuit.

The platform draws inspiration from atomic systems and could have a wide range of applications including photonic quantum information processing, optical signal processing, and microwave photonics. "This is the first time that microwaves have been used to shift the frequency of light in a programmable manner on a chip," said Mian Zhang, a former postdoctoral fellow in Applied Physics at SEAS, now CEO of Harvard-spawned startup HyperLight Corporation and first author of the paper. "Many quantum photonic and classical optics applications require shifting of optical frequencies, which has been difficult. We show that not only can we change the frequency in a controllable manner, but using this new ability we can also store and retrieve light on demand, which has not been possible before." The research was published in Nature Photonics.

Microwave signals are ubiquitous in wireless communications, but researchers thought they interact too weakly with photons. That was before SEAS researchers, led by Marko Loncar, the Tiantsai Lin Professor of Electrical Engineering, developed a technique to fabricate high-performance optical microstructures using lithium niobate, a material with powerful electro-optic properties.

Loncar and his team previously demonstrated that they can propagate light through lithium niobate nanowaveguides with very little loss and control light intensity with on-chip lithium niobate modulators. In the latest research, they combined and further developed these technologies to build a molecule-like system and used this new platform to precisely control the frequency and phase of light on a chip. "The unique properties of lithium niobate, with its low optical loss and

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strong electro-optic nonlinearity, give us dynamic control of light in a programmable electro-optic system," said Cheng Wang, co-first author of the paper and now Assistant Professor at City University of Hong Kong. "This could lead to the development of programmable filters for optical and microwave signal processing and will find applications in radio astronomy, radar technology, and more."

Next, the researchers aim to develop even lower-loss optical waveguides and microwave circuits using the same architecture to enable even higher efficiencies and, ultimately, achieve a quantum link between microwave and optical photons. "The energies of microwave and optical photons differ by five orders of magnitude, but our system could possibly bridge this gap with almost 100 percent efficiency, one photon at a time," said Loncar, senior author of the paper. "This would enable the realization of a quantum cloud — a distributed network of quantum computers connected via secure optical communication channels."

3.Find the English equivalents of the following Russian expression in the text. Make up sentence of your own using them.

Хранить свет, черпать вдохновение в, обработка оптических сигналов, генерировать свет, по требованию, взаимодействовать, передавать свет, порядок возрастания, устранить пробел.

4.Answer the following questions.

1.What kind of a new integrated photonics platform have the researchers developed?

2.How do microwaves help to shift the frequency of light?

3.What do the researchers aim to develop in the future?

5.Retell the article using the phrases from Appendix.

6.Translate the following text into English.

Исследователи разработали новую интегрированную фотонную платформу, которая может сохранять свет и контролировать его частоту. Основу новой платформы составляют созданные ранее высокопроизводительные оптические нановолноводы из ниобата лития. Этот материал обладает высокой электро-оптической нелинейностью и низким коэффициентом оптических потерь, благодаря чему и стал возможен точный динамический контроль частоты и фазы света в экспериментальной программируемой системе на чипе. По мнению авторов, эта разработка приведёт к созданию программируемых фильтров для обработки оптических

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и микроволновых сигналов с приложениями в радиоастрономии, радиолокационных технологиях и во многих других областях.

Unit V. Manhole Covers Serve as Antennas Expanding Wireless Network Coverage

1. Study the following words and expressions.

Multiple-input multiple-output – многоканальный вход/ выход; manhole cover – крышка канализационного люка; deployment – размещение.

2. Read and translate the text.

Manhole antenna solution offers glimpse into 5G strategies for signal propagation. The inconvenient truth of future 5G networks is that their increased high-speed bandwidth, and the use of the millimeter wave spectrum (the radio spectrum above 30 gigahertz) to achieve it, comes at a price: Those radio signals

coverage. Small cell deployment will be so extensive that the Small Cell Forum predicts 5G small cell will overtake 4G small cells by 2024. The total installed base of 5G or multimode small cells will reach 13.1 million by 2025, constituting more than one-third of the total small cells in use.

So, how do you manage to get all of these small cells dispersed throughout a city landscape where buildings are everywhere and there’s little open space for signals to travel? Engineers at Vodafone, headquartered in the United Kingdom, have come up with an ingenious solution: make manhole covers do double duty as antennas for mobile communications. This clever solution manages to avoid all the troubling issues that had worried many observers about the proliferation of small cells. It eliminates traffic disruptions from street construction, and there are no antennas awkwardly placed on buildings, marring the appearance of a neighborhood.

This solution is currently being used for existing 4G networks, but Vodafone engineers believe this could be a solution for future 5G networks as well. “The manholes do provide an opportunity to deliver solutions in dense urban environments,” said James Grayling, senior network deployment manager, Vodafone UK.

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While there is a possibility that the manhole covers could be used for 5G networks — and Vodafone gives a fair amount of credence to the connection in their press release — a Vodafone spokesperson remained noncommittal as to whether this will indeed be a part of Vodafone’s overall 5G strategy. “We envisage that we may be able to use the manhole coverage solutions for 5G rollout going forward but this is still to be decided,” said Ally Stevens, a network media relations manager for Vodafone UK. Nonetheless, Grayling did reveal some of the manhole antennas’ impressive capabilities. “The antenna currently being used has a frequency range of 1695 megahertz to 2690 Mhz, and is being used with 4G where download speeds of up to 195 megabits per second can be achieved,” said Grayling.

While it may seem that the big metal manhole covers would interfere with signals, Grayling insists that is not the case. “The manhole does not interfere with the mobile signals, although there is a small level of power loss caused by the manhole,” said Grayling. “This is taken into account when designing where we want to deploy such solutions.”

It’s not yet clear how extensive the deployment of the special manhole covers will be. When asked whether there was any number of manhole antennas they were targeting to be put out into the field, Vodafone’s spokespeople demurred. “We are in the process of identifying assets in our fixed network that can be best utilized to meet the needs of the mobile network,” was all Grayling would say in response.

3.Find the English equivalents of the following Russian expression in the text. Make up sentence of your own using them.

Предложить ознакомиться, дорого обходиться, распространяться по городу, остроумное решение, портить вид, плотная городская застройка, уклониться от ответа, определить достоинства.

4.Answer the following questions:

1.What is the major setback to future 5G networks?

2.What solution for future 5G networks have the engineers offered?

3.What are the advantages of manhole antennas?

5.Retell the article using the phrases from Appendix.

6.Translate the following text into English.

Британская компания Vodafone предложила оригинальное и практичное решение проблемы: 5G антенна может быть вмонтирована в

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крышки канализационных люков. У такого предложения есть ряд весомых преимуществ: простота монтажа – не придется проводить строительные работы, устанавливать вышки, портить крыши домов; множество передатчиков, так как люки расположены на равном расстоянии и встречаются на всех улицах. К тому же они располагаются на открытом пространстве, поэтому препятствий для прохождения радиочастот немного; технология уже используется для 4G, остается заменить ретрансляторы на устройства нового поколения. Несмотря на радужные перспективы, существует и ряд недостатков: в первую очередь придется переделать люки, которые должны иметь высокую пропускную способность. Традиционные крышки изготавливаются из металла и блокируют радиочастоты.

Unit VI. How AI is Starting to Influence Wireless Communications 1. Study the following words and expressions.

End-to-end – комплексный;

machine learning algorithm – алгоритм машинного обучения; software development kit – комплект разработки ПО; non-line-of-sight communications – загоризонтная радиосвязь;

FPGA — field programmable gate array – программируемая логическая интегральная схема;

anti-jam capabilities – степень помехозащищенности;

SDR – software defined radio – программно-определяемая радиосистема; batch phase – порционная фаза.

2. Read and translate the text.

Machine learning and deep learning technologies are promising an end-to- end optimization of wireless networks while they commoditize PHY and signalprocessing designs and help overcome RF complexities. What happens when artificial intelligence (AI) technology arrives on wireless channels? For a start, AI promises to address the design complexity of radio frequency (RF) systems by employing powerful machine learning algorithms and significantly improving RF parameters such as channel bandwidth, antenna sensitivity and spectrum monitoring.

Combining deep learning-based sensing with active radio waveforms creates a new class of use cases that can intelligently operate in a variety of radio environments. The following section will present a couple of design case studies that demonstrate the potential of AI technologies in wireless communications.

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Two design case studies.

First, the OmniSIG software development kit (SDK) from DeepSig Inc. is based on deep learning technology and employs real-time signal processing to allow users to train signal detection and classification sensors. DeepSig claims that its OmniSIG sensor can detect Wi-Fi, Bluetooth, cellular and other radio signals up to 1,000 times faster than existing wireless technologies. Furthermore, it enables users to understand the spectrum environment and thus facilitate contextual analysis and decision making.

ENSCO, a U.S. government and defense supplier, is training the OmniSIG sensor to detect and classify wireless and radar signals. Here, ENSCO is aiming to deploy AI-based capabilities to overcome the performance limitations of conventionally designed RF systems for signal intelligence. What DeepSig’s OmniPHY software does is allow users to learn the communication system, and subsequently optimize channel conditions, hostile spectrum environments and hardware performance limitations. The applications include anti-jam capabilities, non-line-of-sight communications, multi-user systems in contested spectrums and mitigation of the effects of hardware distortion.

Another design case study showing how AI technologies like deep learning can impact future hardware architectures and designs is the passive Wi-Fi sensing system for monitoring health, activity and well-being in nursing homes. The continuous surveillance system developed at Coventry University employs gesture recognition libraries and machine learning systems for signal classification and creates a detailed analysis of the Wi-Fi signals that reflect off a patient, revealing patterns of body movements and vital signs. Residential healthcare systems usually employ wearable devices, camera-based vision systems and ambient sensors, but they entail drawbacks such as physical discomfort, privacy concerns and limited detection accuracy. On the other hand, a passive Wi-Fi sensing system, based on activity recognition and through-wall respiration sensing, is contactless, accurate and minimally invasive.

A passive Wi-Fi sensing system is a receive-only system that measures the dynamic Wi-Fi signal changes caused by moving indoor objectives across multiple path propagation. Here, AI technologies like machine learning allow engineers to use frequency to measure the phase changing rate during the measurement duration as well as Doppler shift to identify movements.

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Machine learning algorithms can establish the link between physical activities and the Doppler-time spectral map associated with gestures such as picking things up or sitting down. The phase of the data batches is accurate enough to discern the small body movements caused by respiration.

Coventry University built a prototype of a passive Wi-Fi sensing system using Universal Software Radio Peripheral (USRP) and LabVIEW software to capture, process and interpret the raw RF signal samples. LabVIEW, an intuitive graphical programming tool for both processors and FPGAs, enables engineers to manage complex system configurations and adjust signal processing parameters to meet the exact requirements.

On the other hand, USRP is an SDR-based tunable transceiver that works in tandem with LabVIEW for prototyping wireless communication systems. It has already been used in prototyping wireless applications such as FM radio, direction finding, RF record and playback, passive radar and GPS simulation.

Engineers at Coventry University have used USRP to capture the raw RF samples and deliver them to the LabVIEW application for speedy signal processing. They have also dynamically changed the data arrays and batch size of analysis routines to adapt the system to slow and fast movements. Engineers were able to interpret some captured signals and directly link the periodic change of batch phase with gestures and respiration rate. Next, they examined if the phase of the data batches was accurate enough to discern the small body movements caused by respiration.

The above design examples show the potential of AI technologies like machine learning and deep learning to revolutionize the RF design, addressing a broad array of RF design areas and creating new wireless use cases. These are still the early days of implementing AI in wireless networks. But the availability of commercial products such as USRP suggests that the AI revolution has reached the wireless doorstep.

3.Find the English equivalents of the following Russian expression in the text. Make up sentence of your own using them.

Преодолеть трудности, упростить анализ, неблагоприятная среда, смягчение последствий, показатели жизнедеятельности, содержать недостатки, установить связь, соответствовать требованиям.

4.Answer the following questions.

1.In what way can AI technologies influence wireless communications?

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2.What does deep-learning technology imply?

3.How can AI technologies impact future health monitoring?

5.Retell the article using the phrases from Appendix.

6.Translate the following text into English.

Машинное обучение является одним из направлений искусственного интеллекта. Основной принцип заключается в том, что машины получают данные и “обучаются” на них. В отличие от программ с закодированными вручную инструкциями для выполнения конкретных задач, машинное обучение позволяет системе научиться самостоятельно распознавать шаблоны и делать прогнозы. Глубокое обучение является подмножеством машинного обучения. Оно использует некоторые методы машинного обучения для решения реальных задач, используя нейронные сети, которые могут имитировать человеческое принятие решений.

Unit VII. New Spot-Beam Antennas Boost Communication Satellites’ Bandwidth

1.Study the following words and expressions.

Perch – положение; to hover – зависать;

throughput – работоспособность/ пропускная способность; spot-beam antenna – узконаправленная антенна;

struts – кронштейн; propulsion – движение, тяга;

graveyard orbit – орбита захоронения/ длительного существования.

2.Read and translate the text.

Over the past few months, the spacecraft manufacturing company SSL put the finishing touches on three massive communications satellites. Then it initiated its plan to have them launched, one after the other, into distinct geosynchronous orbits 36,000 kilometers above Earth — perches that will keep each satellite hovering over a particular spot, even as the planet turns.

From their respective vantage points, the pair built for Telesat will deliver high-speed communications services, including broadband Internet, to Asia and the Americas for the next 15 years.

At more than 7,000 kilograms, Telstar 19 Vantage became the heaviest commercial communications satellite ever launched when it left Earth on 22 July. But the record-setting 19V and its sibling, Telstar 18 Vantage (which was launched

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on 10 September), are also noteworthy in other ways. What makes them so special? The 18V and 19V feature antennas that can transmit a type of beam that will vastly improve their data throughput. What’s more, SSL used 3D-printing techniques to build and customize both satellites.

Geosynchronous communications satellites send and receive signals over an exceptionally wide coverage area. “With geo, you can cover about one-third of the Earth with one satellite,” says Carolyn Belle, a senior analyst at Northern Sky Research. From certain angles, these satellites can have almost half of the global population within range.

That’s a lot of potential users, spread over a massive area, which is why communications satellites have historically operated with wide-beam coverage. But, as SSL’s acting chief technology officer Rob Schwarz says, spot beams are becoming more popular. Spot beams are focused rays of electromagnetic energy that can transmit more data to smaller areas than wide beams can manage. “An analogy is the human eye and the insect compound eye,” says Schwarz. “The human eye is one wide view, while the compound eye is like spot beams.” Like the components of the multifaceted eye of a dragonfly, the spot beams produced by antennas onboard both the 18V and 19V focus in slightly different directions, allowing the same spectrum bands to be used multiple times without interference.

Eventually, the 18V and 19V will look down on Earth with their spot beams and wide beams, as if through a compound contact lens fitted over an eye. “There will be a backdrop of broad-area beams, and in high-density areas, we’re adding spot beams to aid coverage,” says Schwarz.

Spot beams ultimately function similarly to cell towers. The satellite transmits along a specific band in the general area around the ground station, and the station, tuned into that band, will receive the signal. “It’s like locating a cellphone in a specific cell,” says Schwarz.

The 18V and 19V use the Ku (12 to 18 gigahertz) and Ka (26 to 40 GHz) bands for their spot beams and wide beams. The bands have risen in popularity in recent years because they deliver higher data rates than the 4-to-8-GHz C band commonly used for satellite communications. This shift came despite the fact that higher-frequency bands have a greater signal loss in the atmosphere, particularly in rainy climates.

The Telstar satellites launched by SSL have 3D-printed components in the antenna struts, which support antennas, tracking equipment, and satellite-control

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equipment. The 3D printing speeds up the design process and can create joints that are just as strong but have more complex shapes than those made with traditional assembly, without requiring difficult welding. This technique also cuts down on costs, though geosynchronous satellites remain expensive. “Geosatellites are up in the billions of dollars per satellite” after factoring in the cost of launching, says analyst Belle. Although some startups are pursuing constellations of smaller, low- Earth-orbit satellites as an alternative, Belle says larger satellites remain viable thanks to their efficient power usage and very low cost per bit of data.

As for the trio of new communications satellites, each one must spend about 10 days under its own propulsion after launch to reach its final, geosynchronous orbit. Once there, they deploy their solar arrays and open their antennas. As SSL makes contact with each satellite, it runs checks on every system to ensure the equipment is in optimal condition. Then SSL shepherds the satellites for 30 to 40 days before handing them over to their operators. If they do their jobs well for the next 15 years, then just before each satellite runs out of propellant, it will be boosted into a higher, graveyard orbit. “The graveyard orbit is for the good satellites who have completed their operations,” says Schwarz.

3.Find the English equivalents of the following Russian expression in the text. Make up sentence of your own using them.

Завершить, наблюдательная точка, скорость обработки информации, обширная территория, много раз, сокращать стоимость, завершить работу.

4.Answer the following questions.

1.What makes the communication satellites described in the article so

special?

2.What is implied be the term “spot beams”?

3.What are the advantages of using 3D-printed components in antennas?

5.Retell the article using the phrases from Appendix.

6.Translate the following text into English.

Геостационарный спутник висит над определенной точкой экватора, в точности следуя скорости вращения Земли. Такое положение выгодно по следующим обстоятельствам. Во-первых, четверть поверхности Земли оказывается с такой высоты в зоне прямой видимости, поэтому с помощью геостационарных спутников просто организовать широковещание в пределах страны или даже континента. Во-вторых, сам спутник неподвижен

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