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для наземных антенн, что значительно облегчает организацию связи, так как не нужно автоматически корректировать направление наземной антенны.

В-третьих, геостационарный спутник находится за пределами земной атмосферы и меньше “изнашивается”, чем низкоорбитальные и средневысотные спутники.

Unit VIII. What Role Will Millimeter Waves Play in 5G Wireless Systems? 1. Study the following words and expressions.

Advanced Mobile Phone Service (AMPS) – усовершенствованная мобильная телефонная связь;

CDMA – Code Division Mobile Access – множественный доступ с кодовым разделением каналов;

UMTS – Universal Mobile Telecommunications System – универсальная система мобильной связи;

LTE – Long term evolution – стандарт «Долгосрочное развитие сетей связи».

2. Read and translate the text.

5G will bring mobility to mmWave communications as the next-gen wireless network attempts to serve more people and even things with a major expansion of mobile services.

Wireless communications networks have evolved dramatically from their humble beginnings. The first-generation (1G) wireless network, the Advanced Mobile Phone Service (AMPS) cellular communications standard, was based on analog technology from Bell Labs. But users liked the convenience of carrying a communications device such as a telephone wherever they went, and the number of users grew quickly. Subsequently, second-generation (2G) wireless networks saw the adoption of GSM and CDMA technologies as the first digital standards.

Still, users wanted more functions from their cell phones, so third-generation networks eventually arrived as the first mobile broadband wireless systems. With 3G UMTS technology integrated as the high-speed digital standard, they could send e-mails and data as well as make voice calls. The fourth-generation (4G) wireless network, equipped with Long Term Evolution (LTE) and LTE Advanced digital technologies, was thought to be the last wireless communications network that anyone would ever need—until the need arose for the fifth generation (5G).

In spite of digital techniques and advanced modulation formats, wireless communications generations 1 through 4 have worked with essentially limited

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bandwidth, trying to serve a fast growing number of users wanting more services that consume ever-increasing bandwidth. For example, current 4G LTE wireless network infrastructure equipment in the U.S. operates at 800 MHz, 1900 MHz, 1.7 to 2.1 GHz, and 2.5 to 2.7 GHz. However, it also employs a variety of additional communications technologies, such as wired Ethernet and fiber-optic cables, to transfer data at the highest rates possible. Both fixed and mobile wireless users now expect data rates in excess of 1 Gb/s. With the coming of 5G in approximately two years, data rates are expected to reach 10 Gb/s.

Even with the advances of 4G LTE, the network is running out of bandwidth. The solution, as seen by 5G wireless network developers, is to add more bandwidth by using frequency spectrum in the millimeter-wave frequency range. With hundreds of megahertz of wireless transmission bandwidth available at center frequencies such as 24, 28, and 38 GHz, 5G wireless networks will be capable of almost zero-latency phone calls and extremely high data speeds. Although mmWave frequencies, according to their wavelengths, range from 30 to 300 GHz, 5G innovators working on 5G network solutions typically refer to the mmWave frequency range as starting at about 24 GHz.

People are just one projected part of the many users of 5G networks. Autonomous vehicles will need that 1-ms latency of 5G networks to safely steer through traffic and maintain awareness of the traffic around them by means of vehicle-to-everything (V2X) communications. In addition, potentially billions of Internet of Things (IoT) sensors may be adding their data contributions to 5G networks within the next decade, giving people instant access to information about different things and environments around them. Due to this projected massive bandwidth consumption, developers see mmWave frequencies providing the bandwidth to make 5G possible.

However, there are many reasons why mmWave equipment has remained within astronomy, military, and research applications for so many years, beyond the high cost of the components and the relative scarcity of test equipment for aligning and evaluating the hardware. Electromagnetic (EM) energy at those higher frequencies suffers a great deal of path loss through the air (especially through air with high humidity) compared to lower-frequency signals with longer wavelengths. Signals at 24 GHz and above can be absorbed by any objects in their propagating path, such as buildings, trees, even the hand of someone holding the smartphone that’s sending the mmWave signals to a cell site to connect with a

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listener. But mmWave frequencies also have benefits, in addition to the generous bandwidths they offer, such as their use of much smaller antennas (to fit those smaller wavelengths) compared to lower frequencies. The small size of these antennas makes it possible to pack many of them together into small form factors to benefit from antenna arrays.

The architecture of 5G networks will be much different than earlier wirelessnetwork generations, in part because of the use of mmWave frequencies. Smaller antennas will be used in mobile handsets to transmit and receive those higherfrequency signals but, as noted, the propagation distances for mmWave frequencies is less than for signals at the lower frequencies traditionally used in cellular networks.

As a result, 5G network infrastructure must be erected with many more, smaller cell sites or base stations than lower-frequency wireless networks. In addition, within those smaller cells, many antennas will be used to produce threedimensional (3D) antenna beams, as part of a process known as beamforming.

It is a technology that has long been in use by the military as part of phasedarray radar systems, to create and direct high-energy pulses for reflection from a target. In 5G systems, multiple-element antennas in closely spaced, smaller base stations will use hundreds of antenna elements to form directional beams for transmission and to receive similar 3D beams from adjacent base stations. A user with a mobile handset will have an antenna array with much fewer elements, possibly around 30 within a battery-powered mobile device, to send and receive signals within microwave and mmWave frequency bands.

The actual application of mmWave frequency bands in 5G wireless networks has yet to be determined, although the additional bandwidth they offer is vital to the improved performance promises of 5G networks. The mmWave frequencies, for example, may only be for outdoor use, with indoor cell sites operating at under- 6-GHz frequencies and providing indoor and outdoor-to-indoor coverage. The plan for the buildup of 5G New Radio (NR) infrastructure is not to abandon 4G LTE, but to add to the capacity and coverage already provided by 4G LTE networks.

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

Значительно развиться, скромное происхождение, как следствие, неуклонно растущий, превышающий, мгновенный доступ, примыкающий.

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4.Answer the following questions.

1.How have wireless communications technologies evolved over the years?

2.What do the developers expect from 5G wireless networks?

3.What is the actual application of 5G wireless networks?

5.Retell the article using the phrases from Appendix.

6.Translate the following text into English.

С целью обеспечения более широкой полосы пропускания канала и информационной емкости по сравнению с текущими сетями четвертого поколения ведется разработка сетей пятого поколения 5G. Планируется, что полоса канала составит более 200 МГц, а скорость передачи данных будет достигать десятков гигабит в секунду. Как и для систем четвертого поколения, по мере развития сетей 5G при их внедрении будут применяться новые технологии и методы, направленные на увеличение пропускной способности канала передачи данных. К новым технологиям и методам, свойственным сетям 5G, относятся многоточечный прием-передача (MIMO) с большим количеством приемопередающих антенн, совместный многоточечный прием-передача и адаптивное формирование диаграммы направленности.

Unit IX. Can radar replace stethoscopes? 1. Study the following words and expressions.

Hallmark – «визитная карточка», отличительная черта; Doctoral candidate – аспирант, соискатель;

stenoses – сужение сосудов.

2. Read and translate the text.

In conjunction with researchers at Brandenburg University of Technology (BTU) in Cottbus and the Department of Palliative Medicine at Universitätsklinikum Erlangen, electronic engineers at Friedrich-Alexander- Universität Erlangen-Nürnberg (FAU) have developed a procedure for reliably detecting and diagnosing heart sounds using radar. In future, mobile radar devices could replace conventional stethoscopes and permanent touch-free monitoring of patients' vital functions could be possible using stationary radar devices.

Along with a white coat, a stethoscope is the hallmark of doctors everywhere. Stethoscopes are used to diagnose the noises produced by the heart and lungs. Used in the conventional way, vibrations from the surface of the body are transmitted to a membrane in the chest-piece and then to the user's eardrum where they are perceived as sounds. Acoustic stethoscopes are comparatively

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inexpensive and have been used reliably for several decades, but they have one drawback. The diagnosis of heart murmurs, such as the assessment of heart valve function, is carried out subjectively and is directly dependent on the experience of the doctor conducting the examination.

In a joint project funded by the Federal Ministry of Education and Research, FAU researchers at the Institute of Electronics Engineering (LTE) have now developed a procedure that could eventually replace conventional phonocardiology. Using a six-port continuous wave radar system, they measured the vibrations on the skin caused by the heartbeat. 'In principle, we're using a similar method to detecting speed in road traffic,' explains Christoph Will, a doctoral candidate at LTE. 'During this process, a radar wave is aimed at the surface of an object and reflected. If the object moves, the phase of the reflecting wave changes. This is used to calculate the strength and frequency of the movement — of the chest in our case.' In contrast to radar systems for traffic monitoring, the biomedical radar system can detect changes in movement that measure a few micrometres, which is an important prerequisite to diagnosing even the smallest anomalies such as insufficiency, stenoses or heart valves that do not close properly.

Initial tests were very successful. The test patients were examined in various states of activity such as while resting and after sports and their heart sounds were detected. A direct comparison between the radar system and conventional standard instruments with a digital stethoscope and an electrocardiograph (ECG) showed a very high correlation. 'While diagnosing S1, which is the first heart sound, for example, we achieved a correlation of 92 percent with the ECG,' says Kilin Shi, who is also a doctoral candidate at LTE. 'The correlation was 83 percent in a direct comparison of the signal shapes with the digital stethoscope. That's absolutely reliable.' The researchers say that the slight deviations are caused by the fact that measurements using the radar system and the reference systems cannot be carried out simultaneously on exactly the same place on the body. In addition, the radar system measures a surface area and not a single spot like the stethoscope, which is also a reason for the varying measurement values.

The FAU researchers are optimistic that mobile radar systems could replace conventional stethoscopes in diagnosing heart function in the near future. A significant advantage offered by radar is the fact that the values are recorded digitally and are thus not subjective allowing human error to be increasingly ruled

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out during the diagnosis of anomalies or diseases. Using biomedical radar systems for automated prophylactic examinations for example in doctors' waiting rooms, at work, or at home, is also feasible.

The researchers are already working on another project for monitoring the vital functions of patients who are seriously ill using stationary radar systems around the clock and without disruptive cables. 'Touch-free and therefore stressfree measurement of vital parameters such as heart sounds has the potential to revolutionise clinical care and research, for example, in palliative medicine,' explains Prof. Dr. Christoph Ostgathe, co-author of the study. 'For example, we could inform relatives of terminally ill patients more quickly at the beginning of the dying phase, as the radar system immediately detects any changes in patients' health. It would also be possible to detect any painful symptoms in patients who cannot communicate'.

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

Совместно с, определять с высокой степенью точности, жизненно важные функции, незначительные отклонения, результат измерения, практически возможный, смертельно больной.

4.Answer the following questions.

1.How does a stethoscope work?

2.How does the newly invented biomedical radar system work?

3.What is its advantage in comparison with a conventional stethoscope?

5.Retell the article using the phrases from Appendix.

6.Translate the following text into English.

Новая сенсорная система на основе технологии расширения радиолокационного спектра позволяет измерять сердцебиение удаленно, в режиме реального времени и с точностью электрокардиографа. Разработанная исследователями система дистанционного зондирования сочетает радиолокационную технологию с алгоритмом оценки интервала между сердцебиениями, который идентифицирует различные сигналы, исходящие от тела, изолирует сердцебиения от совокупного радиолокационного сигнала и рассчитывает их интервалы. Исследователи использовали сверхширокополосную радиолокационную систему с умеренной относительной шириной полосы частот, что привело как к

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подавлению помех, так и высокой чувствительности при измерении точных частот сердечных сокращений даже в динамической среде.

Unit X. Quantum radar will expose stealth aircraft 1. Study the following words and expressions.

Stealth aircraft – самолет с низким уровнем демаскирующих признаков; solar flares – вспышки на солнце;

to deflect radio waves – изменять направление радиоволн;

electronic jamming – создание активных преднамеренных радиопомех; to swamp – забивать помехами;

quantum entanglement – квантовая запутанность; telltale signature – демаскирующий признак.

2. Read and translate the text.

New $2.7 million project funded by Department of National Defence will develop technology for quantum radar.

Stealth aircraft in the Canadian arctic will be no match for a new quantum radar system. Researchers at the University of Waterloo are developing a new technology that promises to help radar operators cut through heavy background noise and isolate objects — including stealth aircraft and missiles — with unparalleled accuracy.

“In the Arctic, space weather such as geomagnetic storms and solar flares interfere with radar operation and make the effective identification of objects more challenging,” said Jonathan Baugh, a faculty member at the Institute for Quantum Computing (IQC) who is leading the project with three other researchers at IQC and the Waterloo Institute for Nanotechnology. “By moving from traditional radar to quantum radar, we hope to not only cut through this noise, but also to identify objects that have been specifically designed to avoid detection”.

Stealth aircraft rely on special paint and body design to absorb and deflect radio waves—making them invisible to traditional radar. They also use electronic jamming to swamp detectors with artificial noise. With quantum radar, in theory, these planes will not only be exposed, but also unaware they have been detected.

Quantum radar uses a sensing technique called quantum illumination to detect and receive information about an object. At its core, it leverages the quantum principle of entanglement, where two photons form a connected, or entangled, pair.

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The method works by sending one of the photons to a distant object, while retaining the other member of the pair. Photons in the return signal are checked for telltale signatures of entanglement, allowing photons from the noisy environmental background to be discarded. This can greatly improve the radar signal-to-noise in certain situations. But in order for quantum radar to work in the field, researchers first need to realize a fast, on-demand source of entangled photons. “The goal for our project is to create a robust source of entangled photons that can be generated at the press of a button,” said Baugh.

To date, quantum illumination has only been explored in the laboratory. The Government of Canada, under the Department of National Defence’s All Domain Situational Awareness (ADSA) Science & Technology program, is investing $2.7M to expedite its use in the field.

The 54 North Warning System (NWS) radar stations, based in the Arctic and operated by the North American Aerospace Defense Command (NORAD), are nearing the end of their life spans and could need to be replaced as early as 2025. “This project will allow us to develop the technology to help move quantum radar from the lab to the field,” said Baugh. “It could change the way we think about national security.”

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

Ничто по сравнению с, c непревзойденной точностью, делать более затруднительным, по своей сути, надежный источник, способствовать скорейшему использованию, срок службы.

4.Answer the following questions.

1.What is the primary function of the new quantum radar system?

2.Why is radar operation so challenging in the Arctic?

3.In what way is quantum radar different from traditional radars?

5.Retell the article using the phrases from Appendix.

6.Translate the following text into English.

Квантовый радар работает по принципу «квантовой запутанности» – физического явления в квантовой механике. Радар генерирует пару взаимосвязанных фотонов, один из которых остается контрольным, а второй выпускается в открытое пространство и отражается от окружающих предметов. При возвращении отражённого фотона он коррелирует с контрольным и трансформируется в изображение на экране оператора.

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Сейчас основной задачей ученых является разработка постоянного источника запутанных фотонов, который активировался бы по нажатию кнопки.

Список рекомендуемых источников

Marine Link. URL: https://www.marinelink.com/

Microwave Journal. URL:https://www.microwavejournal.com/

Microwave magazine. URL: https://www.mtt.org/publications/ieee-microwave- magazine/

Science Daily. URL:https://www.sciencedaily.com Science Direct. URL: https://www.sciencedirect.com/ The Scientist. URL:https://www.the-scientist.com

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