[Κινητές και Δορυφορικές] Γενικές απορίες κι ανακοινώσεις/επικαιρότητα 2013/2014

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[Admins]

Για αλλαγή του public name σας, επικοινωνήστε με έναν από τους Admins.

[ampoulog]

LTE Radio Coverage Webinar

http://lteworld.org/video/lte-radio-coverage-webinar

[ampoulog]

5G Service On Your 4G Phone?



A new San Francisco-based start-up, Artemis Networks, announced today that it plans to commercialize its “pCell” technology, a novel wireless transmission scheme that could eliminate network congestion and provide faster, more reliable data connections. And the best part? It could work on your existing 4G LTE phone.

If it proves capable of scaling, pCell could radically change the way wireless networks operate, essentially replacing today’s congested cellular systems with an entirely new architecture that combines signals from multiple distributed antennas to create a tiny pocket of reception around every wireless device. Each pocket could use the full bandwidth of spectrum available to the network, making the capacity of the system “effectively unlimited,” says Steve Perlman, Artemis’s CEO.

First introduced in 2011 under the name DIDO (for distributed input, distributed output), pCell seems almost too fantastic to believe. And no doubt Artemis will have plenty of critics to pacify and kinks to smooth out before operators like Verizon or AT&T pay serious attention. But there are at least a couple reasons why the idea might have some real legs.

First, it’s an elegant solution to a persistent global problem. Wireless traffic is more than doubling each year and cellular operators are struggling to keep up with that growth. “Demand for spectrum has outpaced our ability to innovate,” says Perlman, whose past entrepreneurial ventures include the cloud-based gaming service OnLive and WebTV (now MSN TV), which he sold to Microsoft in 1997.

The reason isn’t for a lack of ideas. The wireless industry is pursuing plenty of them, including small cells, millimeter-wave spectrum, fancy interference coordination, and multiple antenna schemes such as MIMO. But Perlman thinks many of these fixes are just clever kludges for an outdated system. The real bottleneck, he argues, is the fundamental design of the cellular network. “There is no solution if you stick with cells,” he says.

What’s wrong with cells? In a word: interference. Base stations and wireless devices must carefully coordinate their transmission power and spectrum use so that they don’t jam one another’s signals. This ability to divide spectrum resources among many users has been at the heart of mobile systems pretty much since they emerged in the 1980s. It’s also the reason why data rates tend to plummet when many users try to use the same cells, such as in New York City’s Times Square.

Artemis is approaching wireless transmission in a completely new way. Basically, its pCell technology could allow each wireless device to use the full bandwidth of the network regardless of how many users join and how tightly they’re packed together. It’s as if your phone were continuously the sole user of its own personal cell. Hence the name pCell.

To understand how such a system would work, let’s start with the basic set-up. To deploy the technology, an operator would first need a cloud-based data center—a rack or many racks of connected servers that would do all the heavy computation for the system. The operator would then need to install radio antennas where its customers are located, such as in homes, businesses, and city streets. Although these access points might look like small cells (Artemis’s, pictured below, are about the size of a hat box), they’re unlike ordinary base stations. “They’re dumb devices,” Perlman says, serving merely as waypoints for relaying and deciphering signals. Each one could be placed anywhere that’s convenient and would link back to the data center through a fiber or wireless line-of-sight Internet connection.



Now suppose that your phone wants to connect with this pCell network. It would simply send out an access request as it normally does. And all of the “dumb” antennas in your vicinity—let’s say there are 10 of them—would pick up those signals and relay them to the data center.

That’s where things get interesting. Say, for example, you play a YouTube video. The pCell data center would request the video from Google’s servers, and then stream it to your phone through those 10 antennas. But here’s the key innovation: No one antenna would send the complete stream or even part of the stream. Instead, the data center would use the positions of the antennas and the channel characteristics of the system, such as multipath and fading, to calculate 10 unique waveforms, each transmitted by a different antenna. Although illegible when they leave the antennas, these waveforms would add up to the desired signal at your phone, exploiting interference rather than trying to avoid it.

And as you move about, and as other devices connect to and drop off the network, the data center would continuously recalculate new waveforms so that each device receives the correct aggregate signal. “There’s no handoffs and one has to take turns,” Perlman says. “You could literally light up a whole city using all the same spectrum.”

If pCell technology does take off in the next few years, it will likely be because it’s compatible with 4G LTE phones. It does this by simulating LTE base stations in software. The data center would use these virtual radios to inform its waveform calculations, essentially tricking an LTE phone into believing it’s connected to a physical base station. “Your phone thinks its the only phone in the cell and is sitting right next to the tower,” Perlman says. The same technique could also work for other wireless standards, such as 3G and Wi-Fi, he says.

So will operators adopt pCell? It’s unlikely that LTE carriers would replace their networks any time soon, even if Artemis’s technology proves to be the “sea change” Perelman believes it is. But its compatibility with LTE changes the game. For instance, operators could deploy pCell antennas in congested hot spots such as airports, sports stadiums, and city centers—places where they’re already investing in new infrastructure. Users could roam seamlessly between the two networks without having to buy new phones or switch service plans.

Artemis says it plans to license pCell to wireless carriers and Internet service providers. The company is now beginning large-scale trials in San Francisco and expects the technology will be ready for commercial rollouts by the end of 2014. It will be fascinating to see how its ambitions pan out.

source: http://spectrum.ieee.org/tech-talk/telecom/wireless/5g-service-on-your-4g-phone/?utm_source=techalert&utm_medium=email&utm_campaign=022014

[ampoulog]

LTE-A R.10 tutorial video ~6 min!


http://www.mastertelecomfaster.com/lte10/overview.php

[ampoulog]

[book] Fundamentals of Wireless Communication

Excerpt: The writing of this book was prompted by two main developments in wireless communication in the past decade. First is the huge surge of research activities in physical-layer wireless communication theory. While this has been a subject of study since the sixties, recent developments such as opportunistic and multiple input multiple output (MIMO) communication techniques have brought completely new perspectives on how to communicate over wireless channels. Second is the rapid evolution of wireless systems, particularly cellular networks, which embody communication concepts of increasing sophistication. This evolution started with second-generation digital standards, particularly the IS-95 Code Division Multiple Access standard, continuing to more recent third-generation systems focusing on data applications. This book aims to present modern wireless communication concepts in a coherent and unified manner and to illustrate the concepts in the broader context of the wireless systems on which they have been applied.

link: http://www.eecs.berkeley.edu/~dtse/Chapters_PDF/

[ampoulog]

DVB S2

http://www.advantechwireless.com/wp-content/uploads/DVB-S2-theory.pdf

[ampoulog]

Αποτελέσματα Εξεταστικής Φεβρουαρίου 2014 στο eThmmy.


Όποιος θέλει μπορεί να έρθει να δει το γραπτό του τη Δευτέρα 11.00 πμ

[ampoulog]

Μία ακόμη ωραία παρουσίαση για το LTE-A:

http://www.tekna.no/ikbViewer/Content/787700/18%20LTE-Advanced..

[ampoulog]

An excellent webinar presented by Rohde & Schwarz on the basics of Long Term Evolution (LTE) a year ago.

Part 01 - LTE Introduction

Part 02 - LTE Parameters and Downlink Modulation

Part 03 - OFDMA and Downlink Frame Structure Details

Part 04 - SC-FDMA and LTE Uplink

Part 05 - Network and Protocol Architecture

Part 06 - Channel Mapping and UE Categories

Part 07 - Initial Cell Search and Cell Selection

Part 08 - System Information

Part 09 - Random Access Procedures and EPS Bearer Setup

Part 10 - Uplink Channels and Signals

Part 11 - LTE Mobility and MIMO Introduction

Part 12 - Downlink and Uplink MIMO in LTE

Part 13 - eNodeB and UE Performance Requirements

Part 14 - UE Certification and Field Trials



link: http://lteworld.org/presentation/long-term-evolution-lte-basics

[ampoulog]

LTE-A and Beyond

http://www.rsm.govt.nz/cms/pdf-library/policy-and-planning/events/presentations-at-seminar-for-future-wireless-technologies-4-nov-2010/LTE_A_and_Beyond_Huawei.pdf

[ampoulog]

5G: A Technology Vision

5G wireless networks will support 1,000-fold gains in capacity, connections for at least 100 billion devices, and a 10 Gb/s individual user experience capable of extremely low latency and response times. Deployment of these networks will emerge between 2020 and 2030. 5G radio access will be built upon both new radio access technologies (RAT) and evolved existing wireless technologies (LTE, HSPA, GSM and WiFi). Breakthroughs in wireless network innovation will also drive economic and societal growth in entirely new ways. 5G will realize networks capable of providing zero distance connectivity between people and connected machines.

[ampoulog]

Gearing up for a new era in Earth observation

Aiming for launch at the end of March, the first satellite built specifically for Europe’s ambitious Copernicus environmental monitoring programme is now in the last stages of testing before being shipped to French Guiana for liftoff.

Rising to the challenges of global change and the need to manage the environment more effectively, Copernicus offers a set of key information services for a multitude of environmental and civil security applications.



The provision of timely and accurate data is central to this innovative global monitoring programme so ESA is developing six families of Sentinel satellite missions. Each carries state-of-the-art technologies to supply a stream of complementary imagery and data tailored to the needs of Copernicus.

 
Stowed for testing
The data from the Sentinels are open to users worldwide and free of charge.

Sentinel-1, the first in the family of Copernicus satellites, marks a new paradigm in Earth observation and the start of a new era that sees the shift from demonstration and research to operational missions set to support users for decades to come.

This new satellite will be used to care for many aspects of our environment, from detecting and tracking oil spills and mapping sea ice to monitoring movement in land surfaces and mapping changes in the way land is used.

It will also play a crucial role in providing timely information to help respond to natural disasters and help humanitarian efforts.


 
Radar vision
As a radar mission, it can image Earth’s surface through cloud and rain and during the day and night.

This all-weather capability, for example, makes it ideal for monitoring floods, which are typically accompanied by cloud cover, and for monitoring the polar regions, which are shrouded in darkness during the winter months.

Sentinel-1 also carries a laser to transmit data to the European Data Relay System, EDRS, for fast delivery to Earth. EDRS is a network of ground stations and multiple satellites in geostationary orbit designed for relaying data.

The Sentinel-1 mission, as with Sentinel-2 and Sentinel-3, is a constellation of two identical satellites to provide optimal global coverage.


 
Simulated Sentinel-1 image
Sentinel-1A is now nearing its time to be launched into orbit. Its sister satellite, Sentinel-1B, will follow in 2015.  

This first Sentinel spent the last months being put through its paces first at Thales Alenia Space in Rome Italy, and now in Cannes, France.

The latest round of tests has included carefully determining its mass and centre of gravity as well as vibration, acoustic and launcher separation shock tests.


 
Sentinel-1 under mechanical tests
Having accurate knowledge of the satellite’s total mass and centre of gravity, for example, is vital for manoeuvring it in orbit.

Simulating the vibrations and noise of launch and the shock of the separation from the rocket ensure that the satellite and its various components are able to withstand this all-important step of getting this carefully engineered craft safely into orbit around Earth.



Over the next weeks, engineers at Thales Alenia Space will be completing the few remaining tests, which include checking that the solar panels and radar deploy correctly, before packing it up for shipment to Europe’s spaceport in Kourou in French Guiana.

Shipment is currently planned for 21 February.


Πηγή: http://www.esa.int/Our_Activities/Observing_the_Earth/Copernicus/Gearing_up_for_a_new_era_in_Earth_observation

[ampoulog]

Webinar

M2M Managing the Risks of Today
Some of the same elements that have given rise to the M2M industry boom have also enabled a variety of new security threats. In this webinar we will discuss the latest security solutions in M2M. Case studies and trends for the future in M2M Security will be presented as well.


https://mwjournalevents.webex.com/mw0401l/mywebex/default.do?nomenu=true&siteurl=mwjournalevents&service=6&rnd=0.3320620266856623&main_url=https%3A%2F%2Fmwjournalevents.webex.com%2Fec0701l%2Feventcenter%2Fevent%2FeventAction.do%3FtheAction%3Ddetail%26confViewID%3D1004650487%26%26%26%26siteurl%3Dmwjournalevents

[ampoulog]

LTE and the Evolution to LTE-Advanced Fundamentals

http://www.youtube.com/watch?v=-62ol7zW9Zc

[ampoulog]

LTE-A PHY Layer Overview & Femto Design Challenges

http://www.youtube.com/watch?v=JyKJ4_CybiE

[ampoulog]

CERN and ESA sign cooperation agreement

At a ceremony today at Geneva airport, CERN and ESA signed a framework agreement for future cooperation on research and technology in areas of mutual interest. Future areas may include the development and characterization of innovative materials for applications in extreme conditions and for cutting-edge scientific performances, the development of new micro-technologies to be applied in miniaturized distributed sensor systems and the development and testing of high-performance detectors for high-energy physics experiments and space payloads.
“CERN and ESA have common roots and share a long history of pioneering research work in their respective fields,” said CERN Director General Rolf Heuer. “This new cooperation agreement will foster synergies between the expertise, know-how and facilities available in the two Organizations.”
This year is CERN’s 60th anniversary and ESA’s 50th, making the signature an opportunity to celebrate the memory of a scientist who was a founding father of both organizations: the Italian, Edoardo Amaldi (1908 –1989).
Amaldi had an unshakeable belief in the open nature of science and the need for international cooperation. After participating in the creation of CERN during the 1950s, he became Secretary General of the provisional organization. Then, in 1958 when CERN was firmly established, he joined forces with French physicist Pierre Auger to urge European governments to set up a European organisation for space research, based on the CERN model. Their vision led to the founding of the European Space Research Organisation (ESRO), which later became ESA.
During the ceremony, ESA Director General Jean-Jacques Dordain presented Heuer with copies of letters by Amaldi in which he lays out his concern for peace, and the role science should play in fostering it. These letters were flown aboard ESA’s Automated Transfer Vehicle 3 – a spacecraft named in Amaldi’s honour.  The ceremony took place in the presence of members of Amaldi’s family, along with Research Ministers and State Secretaries from Belgium, France, Italy and Switzerland.
“ESA and CERN are the daughters of visionaries like Amaldi,” said Dordain, “testimony that, when we share the same challenging objectives and join forces, Europe is at the leading edge of progress, innovation and growth.”

Source: http://home.web.cern.ch/about/updates/2014/03/cern-and-esa-sign-cooperation-agreement