Definition
During the past year, mobile and integrated fixed/mobile operators announced an increasing number of fixed-mobile convergence initiatives, many of which are materializing in 2006. The majority of these initiatives are focused around UMA, the first standardized technology enabling seamless handover between mobile radio networks and WLANs. Clearly, in one way or another, UMA is a key agenda item for many operators.
Operators are looking at UMA to address the indoor voice market (i.e. accelerate or control fixed-to-mobile substitution) as well as to enhance the performance of mobile services indoors. Furthermore, these operators are looking at UMA as a means to fend off the growing threat from new Voice-over-IP (VoIP) operators.
However, when evaluating a new 3GPP standard like UMA, many operators ask themselves how well it fits with other network evolution initiatives, including:
o UMTS
o Soft MSCs
o IMS Data Services
o I-WLAN
o IMS Telephony
This whitepaper aims to clarify the position of UMA in relation to these other strategic initiatives. For a more comprehensive introduction to the UMA opportunity, refer to "The
UMA Opportunity," available on the Kineto web site (www.kineto.com).
Mobile Network Reference Model
To best understand the role UMA plays in mobile network evolution, it is helpful to first
introduce a reference model for today's mobile networks. Figure 1 provides a simplified
model for the majority of 3GPP-based mobile networks currently in deployment. Based
on Release 99, they typically consist of the following:
o GSM/GPRS/EDGE Radio Access Network (GERAN): In mature mobile markets, the
GERAN typically provides good cellular coverage throughout an operator's service
territory and is optimized for the delivery of high-quality circuit-based voice services.
While capable of delivering mobile data (packet) services, GERAN data throughput is
typically under 80Kbps and network usage cost is high.
o Circuit Core/Services: The core circuit network provides the services responsible for the vast majority of mobile revenues today. The circuit core consists of legacy Serving and Gateway Mobile Switching Centers (MSCs) providing mainstream mobile telephony services as well as a number of systems supporting the delivery of other circuit-based services including SMS, voice mail and ring tones.
o Packet Core/Services: The core packet network is responsible for providing mobile data services. The packet core consists of GPRS infrastructure (SGSNs and GGSNs) as well as a number of systems supporting the delivery of packet-based services including WAP and MMS.
Introduction
When a disaster occurs it is very important to grasp the situation as soon as possible. But it is very difficult to get the information from the ground because there are a lot of things which prevent us from getting such important data such as clouds and volcanic eruptions. While using an optical sensor, large amount of data is shut out by such barriers. In such cases, Synthetic Aperture Radar or SAR is a very useful means to collect data even if the observation area is covered with obstacles or an observation is made at night at night time because SAR uses microwaves and these are radiated by the sensor itself. The SAR sensor can be installed in some satellite and the surface of the earth can be observed.
To support the scientific applications utilizing space-borne imaging radar systems, a set of radar technologies have been developed which can dramatically lower the weight, volume, power and data rates of the radar systems. These smaller and lighter SAR systems can be readily accommodated in small spacecraft and launch vehicles enabling significantly reduced total mission cost.
Specific areas of radar technology development include the antenna, RF electronics, digital electronics and data processing. A radar technology development plan is recommended to develop and demonstrate these technologies and integrate them into the radar missions in a timely manner. It is envisioned that these technology advances can revolutionize the approach to SAR missions leading to higher performance systems at significantly reduced mission costs.
The SAR systems are placed on satellites for the imaging process. Microwave satellites register images in the microwave region of the electromagnetic spectrum. Two mode of microwave sensors exit- the active and the passive modes. SAR is an active sensor which carry on -board an instrument that sends a microwave pulse to the surface of the earth and register the reflections from the surface of the earth.
One way of collecting images from the space under darkness or closed cover is to install the SAR on a satellite . As the satellite moves along its orbit, the SAR looks out sideways from the direction of travel, acquiring and storing the radar echoes which return from a strip of earth's surface that was under observation.
The raw data collected by SAR are severely unfocussed and considerable processing is required to generate a focused image. The processing has traditionally been done on ground and a downlink with a high data rate is required. This is a time consuming process as well. The high data rate of the downlink can be reduced by using a SAR instrument with on-board processing.
X-Band SAR Instrument Demonstrator
The X-band SAR instrument demonstrator forms the standardized part or basis for a future Synthetic Aperture Radar (SAR) instrument with active front- end. SAR is an active sensor. Active sensors carry on-board an instrument that sends a microwave pulse to the surface of the earth and register the reflections from the surface of the earth. Different sensor use different bands in the microwave regions of the electromagnetic spectrum for collecting data. In the X-band SAR instrument, the X-band is used for collecting data.
Introduction
The notion of spying is a very sensitive topic after the September 11 attack of Terrorists in New York. In the novel 1984, George Orwell foretold a future where individuals had no expectation of privacy because the state monopolized the technology of spying. Now the National security Agency Of USA developed a secret project to spy on people for keep tracing their messages to make technology enabled interception to find out the terrorist activities across the globe, named as Echelon. Leaving the technology ahead of the any traditional method of interception .
The secret project Developed by NSA (National Security Agency of USA) and its allies is tracing every single transmission even a single of keyboard. The allies of USA in this project are UK, Australia, New Zealand and Canada. Echelon is developed with the highest computing power of computers connected through the satellites all over the world. In this project the NSA left the wonderful method of Tempest and Carnivores behind.
Echelon is the technology for sniffing through the messages sent over a network or any transmission media, even it is wireless messages. Tempest is the technology for intercepting the electromagnetic waves over the air. It simply sniffs through the electromagnetic waves propagated from any devices, even it is from the monitor of a computer screen. Tempest can capture the signals through the walls of computer screens and keystrokes of key board even the computer is not connected to a network. Thus the traditional way of hacking has a little advantage in spying.
For the common people it is so hard to believe that their monitor can be reproduced from anywhere in one kilometer range without any transmission media in between the equipment and their computer. So we have to believe the technology enabled us to reproduce anything from a monitor of computer to the Hard Disks including the Memory (RAM) of a distant computer without any physical or visual contact. It is done with the Electromagnetic waves propagated from that device.
The main theory behind the Tempest(Transient Electromagnetic Pulse Emanation Standard.) is that any electronic or electrical devices emit Electromagnetic radiations of specific key when it is operated. For example the picture tube of computer monitor emits radiations when it is scanned up on vertical of horizontal range beyond the screen. It will not cause any harm to a human and it is very small. But it has a specific frequency range. You can reproduce that electromagnetic waves by tracing with the powerful equipments and the powerful filtering methods to correct the errors while transmission from the equipment. Actually this electromagnetic waves are not necessary for a human being because it not coming from a transmitter, but we have a receiver to trace the waves.
For the project named as Echelon the NSA is using supercomputers for sniffing through the packets and any messages send as the electromagnetic waves. They are using the advantage of Distributed computing for this. Firstly they will intercept the messages by the technology named as the Tempest and also with the Carnivore. Every packet is sniffed for spying for the USA's NSA for security reasons.
