Archive for May, 2008

RFID privacy and security

Saturday, May 31st, 2008

The issues of privacy and security, although interrelated, are different. With respect to RFID, we define these issues as follows:

Privacy: the ability of the RFID system to keep the meaning of the information transmitted between the tag and the reader secure from non-intended recipients.

Security: the ability of the RFID system to keep the information transmitted between the tag and the reader secure from non-intended recipients.

The issues have very different repercussions and different solutions. In a given environment, an RFID solution may pose security risks without affecting the issue of privacy. An example of this scenario is when a tag broadcasts its unique identification number in a consistent and unencrypted manner. This enables the tag to be detected by any reader that can decode the RF signal. If all that is read is the tag’s unique identifier – and no association can be made to what that identifier means without access to the backend database that maintains the relationship between the tag IDs and the objects that they represent – there is no privacy issue. However, issues of traceability and inventorying may remain.

Traceability and inventorying relate to the ability of an unauthorized entity to read the identifiers sent by RFID tags without necessarily being concerned as to what the tag is affixed to or who/what is carrying it. In other words just by capturing the signals emitted by an RFID tag, a third party could trace where the tag is or has been (traceability) as well as to what tags have been detected (inventorying).

A standard EPC tag conveys information associated with a particular item, its model or product class and its manufacturer. Anyone with a standard EPC reader could get close enough to a shopper leaving a store to determine what products and what quantities were purchased. Furthermore, the unauthorized reader could track the shopper from a distance utilizing a high-powered reader.

The issue of privacy

RFID is an excellent technology for object tracking. In this case, we can define an object as a physical asset that occupies 3-dimensional space. This means that the whereabouts of any physical object (including animals and humans) can potentially be tracked within the scope of the RFID infrastructure. As RFID technology development progresses, this scope can become larger and larger.

This fact has raised many questions and concerns from people because of the potential invasion of privacy that can be attributed to RFID technology. But, before we get deeper into the privacy issues and their repercussions, let’s look at a few examples of what privacy advocates and the concerned public claim can go wrong with the use of RFID technology.


Z-Wave Web-Enabled Door Lock

Saturday, May 31st, 2008

Well-known producer of door locks Schlage is planning to add more intelligent in its products. It’s going to add Z-Wave-based looks line to provide consumers connect them to existing home automation systems or just manage them remotely via Internet.

The new product will be based on Schlage’s line of keypad locks and will have two-way Z-Wave RF technology built in. The battery-operated locks communicate with a Z-Wave gateway that connects to any broadband router. Since Z-Wave is a standards-based protocol, other Z-Wave-compatible controllers could operate the locks as well.

Remember that LinuxMCE has basic Z-Wave interface. So, you can try the new Schlage’s Z-Wave door lock when it’ll be released.

Different GPS wildlife tracking solutions

Saturday, May 31st, 2008
WildLife Tracking

GPS wildlife Tracking or GPS Telemetry is another high-potential growth area for GPS applications. With ever smaller dimensions and weights and the availability of solar cell power these devices can be used in a growing number of cases. For most of us GPS tracking means probably GPS vehicle tracking systems, but we will show even more spectacular applications in quite different fields.

Collecting GPS data is one thing, but reading the data is often more complicated and, especially in real-time, rather expensive. The simpler ‘passive’ units store the data in internal memory. Data can only be read, once the unit is retrieved by the user or sometimes when the unit comes within the reach of a radio connection between the unit and a (portable) receiver.

More sophisticated GPS wildlife tracking units send the data via a cellular phone network in regular time intervals or on demand in the case of units with two-way communication. It is obvious that this only can function within the coverage area of the cellular phone network.

Two-way communication has the extra advantage that the programming of the unit can be modified, even with the unit in use and at distance. This way the user can change the time intervals between reports, or even met the unit in a pause position.

The most expensive GPS wildlife tracking systems send the data in regular intervals via satellites (Argos, GlobalStar). This stands for a really global coverage, but is not a real time solution as the satellites can not be reached 24h/24h. Data can only be sent or received when a satellite is overhead.

GPS Wildlife tracking systems

GPS wildlife tracking systems are now available for almost all mammals and even for the bigger birds. In 1994 the first collar, the Lotek GPS_1000 weighed 1.8 kg and was too heavy for mid-sized mammals. Less than 10 years later Microwave Telemetry has developed the PTT-100, a 70 gr solar powered GPS tracking system that transmits the data to the Argos satellite system. We present some other manufacturers and their programs.

The above-mentioned Lotek specializes in GPS collars for small to large mammals. Their collars contain a VHF tracking beacon. Other innovations include remote two-way communication, which allows you to retrieve data on demand and/or reprogram the collar while it is still on the animal. Temperature and mortality sensors as well as field uploads and downloads. All the GPS wildlife tracking collars can be equipped with a remote release mechanism or a drop-off mechanism that is activated after the expiration of a factory pre-programmed time delay.

Televilt Sweden manufactures three different types of collars as well as backpacks for birds. The GPS-Simplex uses a radio link while GPS-Direct and GPS-Weblink use a cell phone modem (GSM 900/1800). All systems can be fitted with a drop off (pre-programmed or remote control release). Televilt only uses Lithium batteries. GPS-Direct and GPS-Weblink are customer programmable while on animal.

Telemetry Solutions is a Californian based telemetry company involved in GPS wildlife tracking since 1998. Last year the development of a proper GPS collar started. The project focuses on equipment reliability (expressed in back-up VHF beacon, two built-in drop off units, custom made GPS receiver amplifier etc.) and how the product is supported. TS intends to deliver a very reliable system and back it up with customer support. This may not seem as anything new; however, wildlife biologists all around the world are used to failing GPS collars and not too friendly customer support. TS intends to change that, to the better. Toma Track is their distributor of GPS wildlife tracking devices in Europe, Africa and the Middle East.

BlueSky Telemetry in the UK manufactures GPS tracking collars. The modular design of each collar range enables the biologist to pick and choose different components to suit their individual application. The following options are available: GSM mobile telephone engine, UHF radio modem and Satellite telephone engine, enabling remote setup and download. Other options include Programmable remote drop-off, Temperature, Mortality and Activity sensors and a VHF or UHF radio telemetry beacon.

Telonics has a long history in manufacturing wildlife telemetry, conventional telemetry and tracking devices. Their Store-on-Board GPS Collars for animal tracking applications, with or without ARGOS Uplink, are only part of a program of quality electronics for wildlife, environmental research and special applications.

Wildlife tracking

Environmental Studies from Germany is distributor of Vectronic Aerospace GPS collars. The modular system around the GPS Plus collar offers two completely different options of data download while the collar is still on the animal: via UHF radio link on demand or continuously via GSM mobile phone directly into the office. Several accessories are available: a VHF beacon, an activity/mortality logger, a temperature logger and different drop-off systems. All GPS collars can store the positions of the animal on board in non-volatile flash memory. The same technology is also available as a 160gr backpack for large birds.

Wildlife Track Inc. develops and manufactures telemetry and direction finding systems. Their GPS wildlife tracking collars store up to 6240 three-dimensional locations with date and time in nonvolatile memory. Nominal weight is 500 gr and a VHF beacon is standard on all collars. GPS battery lasts up to 7 years (one fix per day). GPS collar circumference is adjustable and WGS 84 or NAD 83 Datums can be specified upon ordering.

The Advanced Telemetry Systems GPS Remote Release Collar can be remotely triggered to drop off the animal on command with the available ATS Command Unit. The collar will also automatically drop off as it reaches the end of its battery life to ensure data retrieval. Up to 8190 locations can be stored on board the unit. The collar incorporates a VHF transmitter to signal location, the status of the last GPS co-ordinate, mortality and battery conditions. The ATS collar also provides data on animal activity, ambient temperature, mortality, VHF duty cycle program, battery voltage and the amount of time logged on the battery backup.

North Star has developed a line of animal GPS collars and bird borne platform transmitter terminals (PTT’s). Acquisition of GPS locations for store and forward through a satellite service provider can be programmed in a variety of duty cycles.


Kyocera Adds BREW to M2M Developer Tools

Saturday, May 31st, 2008

Kyocera Wireless used this week’s BREW conference in San Diego to take the wraps off two new BREW-enabled modules – the 300 and the 1xD. The modules allow customers to reduce cost by running integrated BREW applications within the embedded module. This reduces the need for external application processors in M2M solutions.

“In leveraging the … BREW platform within our new modules, we are creating additional value and versatility for our customers,” said Dean Fledderjohn, general manager of the M2M product line at Kyocera Wireless.

The 300 module integrates Qualcomm chipsets in a small but rugged form factor and delivers lower power consumption, extended operating temperatures and multimode assisted and integrated autonomous GPS.

The 1xD module provides a cheaper platform for telemetry and other data-only applications that don’t need GPS or voice features. The module’s reduced power consumption, streamlined feature-set and small size reduce the total cost of ownership and make it ideal for remote metering/monitoring and alarm applications.

No need for cables with GSM door entry system

Thursday, May 29th, 2008

Urmet Domus have introduced a simple solution for when audio communication is required as part of a door entry system but where it is not possible to install cables.

Domus Cell is compatible with all major mobile networks and provides GSM connection to Sinthesi door entry panels. The default programming enables users to have the system up and running within minutes and it can provide communication through analogue PABX systems, providing all the benefits of a standard telephone system, without the cost of installing fixed lines.

Domus Cell is a particularly practical and cost effective solution for installers of automated gates and barriers although it is also ideal for site and mobile office applications as the same contact numbers can be used for each new project. Read more about this

GPS: Techniques to improve accuracy

Sunday, May 25th, 2008


Augmentation methods of improving accuracy rely on external information being integrated into the calculation process. There are many such systems in place and they are generally named or described based on how the GPS sensor receives the information. Some systems transmit additional information about sources of error (such as clock drift, ephemeris, or ionospheric delay), others provide direct measurements of how much the signal was off in the past, while a third group provide additional navigational or vehicle information to be integrated in the calculation process.

Examples of augmentation systems include the Wide Area Augmentation System, Differential GPS, Inertial Navigation Systems and Assisted GPS.

Precise monitoring

The accuracy of a calculation can also be improved through precise monitoring and measuring of the existing GPS signals in additional or alternate ways.

After SA, which has been turned off, the largest error in GPS is usually the unpredictable delay through the ionosphere. The spacecraft broadcast ionospheric model parameters, but errors remain. This is one reason the GPS spacecraft transmit on at least two frequencies, L1 and L2. Ionospheric delay is a well-defined function of frequency and the total electron content (TEC) along the path, so measuring the arrival time difference between the frequencies determines TEC and thus the precise ionospheric delay at each frequency.

Receivers with decryption keys can decode the P(Y)-code transmitted on both L1 and L2. However, these keys are reserved for the military and “authorized” agencies and are not available to the public. Without keys, it is still possible to use a codeless technique to compare the P(Y) codes on L1 and L2 to gain much of the same error information. However, this technique is slow, so it is currently limited to specialized surveying equipment. In the future, additional civilian codes are expected to be transmitted on the L2 and L5 frequencies (see GPS modernization, below). Then all users will be able to perform dual-frequency measurements and directly compute ionospheric delay errors.

A second form of precise monitoring is called Carrier-Phase Enhancement (CPGPS). The error, which this corrects, arises because the pulse transition of the PRN is not instantaneous, and thus the correlation (satellite-receiver sequence matching) operation is imperfect. The CPGPS approach utilizes the L1 carrier wave, which has a period 1000 times smaller than that of the C/A bit period, to act as an additional clock signal and resolve the uncertainty. The phase difference error in the normal GPS amounts to between 2 and 3 meters (6 to 10 ft) of ambiguity. CPGPS working to within 1% of perfect transition reduces this error to 3 centimeters (1 inch) of ambiguity. By eliminating this source of error, CPGPS coupled with DGPS normally realizes between 20 and 30 centimeters (8 to 12 inches) of absolute accuracy.

Relative Kinematic Positioning (RKP) is another approach for a precise GPS-based positioning system. In this approach, determination of range signal can be resolved to a precision of less than 10 centimeters (4 in). This is done by resolving the number of cycles in which the signal is transmitted and received by the receiver. This can be accomplished by using a combination of differential GPS (DGPS) correction data, transmitting GPS signal phase information and ambiguity resolution techniques via statistical tests—possibly with processing in real-time (real-time kinematic positioning, RTK).

GPS time and date

While most clocks are synchronized to Coordinated Universal Time (UTC), the atomic clocks on the satellites are set to GPS time. The difference is that GPS time is not corrected to match the rotation of the Earth, so it does not contain leap seconds or other corrections which are periodically added to UTC. GPS time was set to match Coordinated Universal Time (UTC) in 1980, but has since diverged. The lack of corrections means that GPS time remains at a constant offset (19 seconds) with International Atomic Time (TAI). Periodic corrections are performed on the on-board clocks to correct relativistic effects and keep them synchronized with ground clocks.

The GPS navigation message includes the difference between GPS time and UTC, which as of 2006 is 14 seconds due to the leap second added to UTC December 31st of 2005. Receivers subtract this offset from GPS time to calculate UTC and specific timezone values. New GPS units may not show the correct UTC time until after receiving the UTC offset message. The GPS-UTC offset field can accommodate 255 leap seconds (eight bits) which, at the current rate of change of the Earth’s rotation, is sufficient to last until the year 2330.

As opposed to the year, month, and day format of the Gregorian calendar, the GPS date is expressed as a week number and a day-of-week number. The week number is transmitted as a ten-bit field in the C/A and P(Y) navigation messages, and so it becomes zero again every 1,024 weeks (19.6 years). GPS week zero started at 00:00:00 UTC (00:00:19 TAI) on January 6, 1980 and the week number became zero again for the first time at 23:59:47 UTC on August 21, 1999 (00:00:19 TAI on August 22, 1999). To determine the current Gregorian date, a GPS receiver must be provided with the approximate date (to within 3,584 days) to correctly translate the GPS date signal. To address this concern the modernized GPS navigation messages use a 13-bit field, which only repeats every 8,192 weeks (157 years), and will not return to zero until near the year 2137.

GPS modernization

Having reached the program’s requirements for Full Operational Capability (FOC) on July 17, 1995, the GPS completed its original design goals. However, additional advances in technology and new demands on the existing system led to the effort to modernize the GPS. Announcements from the U.S. Vice President and the White House in 1998 initiated these changes, and in 2000 the U.S. Congress authorized the effort, referring to it as GPS III.

The project aims to improve the accuracy and availability for all users and involves new ground stations, new satellites, and four additional navigation signals. New civilian signals are called L2C, L5 and L1C; the new military code is called M-Code. Initial Operational Capability (IOC) of the L2C code is expected in 2008. A goal of 2013 has been established for the entire program, with incentives offered to the contractors if they can complete it by 2011.

GPS interference and jamming

Sunday, May 25th, 2008

Natural sources

Since GPS signals at terrestrial receivers tend to be relatively weak, it is easy for other sources of electromagnetic radiation to desensitize the receiver, making acquiring and tracking the satellite signals difficult or impossible.

Solar flares are one such naturally occurring emission with the potential to degrade GPS reception, and their impact can affect reception over the half of the Earth facing the sun. GPS signals can also be interfered with by naturally occurring geomagnetic storms, predominantly found near the poles of the Earth’s magnetic field. GPS signals are also subjected to interference from Van Allen Belt radiation when the satellites pass through the South Atlantic Anomaly.

Artificial sources

Metallic features in windshield, such as defrosters, or car window tinting films can act as a Faraday cage, degrading reception just inside the car.

Man-made EMI can also disrupt, or jam, GPS signals. In one well documented case, an entire harbor was unable to receive GPS signals due to unintentional jamming caused by a malfunctioning TV antenna preamplifier. Intentional jamming is also possible. Generally, stronger signals can interfere with GPS receivers when they are within radio range, or line of sight. In 2002, a detailed description of how to build a short range GPS L1 C/A jammer was published in the online magazine Phrack.

The U.S. government believes that such jammers were used occasionally during the 2001 war in Afghanistan and the U.S. military claimed to destroy a GPS jammer with a GPS-guided bomb during the Iraq War. Such a jammer is relatively easy to detect and locate, making it an attractive target for anti-radiation missiles. The UK Ministry of Defence tested a jamming system in the UK’s West Country on 7 and 8 June 2007.

Some countries allow the use of GPS repeaters to allow for the reception of GPS signals indoors and in obscured locations, however, under EU and UK laws, the use of these is prohibited as the signals can cause interference to other GPS receivers that may receive data from both GPS satellites and the repeater.

Due to the potential for both natural and man-made noise, numerous techniques continue to be developed to deal with the interference. The first is to not rely on GPS as a sole source. According to John Ruley, “IFR pilots should have a fallback plan in case of a GPS malfunction”. Receiver Autonomous Integrity Monitoring (RAIM) is a feature now included in some receivers, which is designed to provide a warning to the user if jamming or another problem is detected. The U.S. military has also deployed their Selective Availability / Anti-Spoofing Module (SAASM) in the Defense Advanced GPS Receiver (DAGR). In demonstration videos, the DAGR is able to detect jamming and maintain its lock on the encrypted GPS signals during interference which causes civilian receivers to lose lock.

Innovation award honours pioneers of BGAN

Sunday, May 25th, 2008

satelite-dishes14-05-2008 – Two Inmarsat experts have been presented with an innovation award by the mobile satellite industry for leading the development of BGAN.

The Mobile Satellite Users Association (MSUA) presented its innovation award to Inmarsat’s chief scientist Marcus Vilaça and director of systems and network engineering, Alan Howell, at its annual conference in Baltimore in the US on May 13.

MSUA president Tim Farrar said: “The award recognises the exciting new broadband applications that BGAN has enabled on a worldwide basis – including highly portable video, data and voice communications.”

Transforming communications
Both Marcus and Alan are proud that Inmarsat’s team has been recognised for introducing a system which has transformed global mobile broadband communications.

Alan said: “The award is all the more welcome because it came out of the blue. It’ s great that the industry is recognising that BGAN is a highly innovative system.

“Both Marcus and I feel a lot of personal attachment to BGAN – the fact that other people recognise its capabilities too is even more appreciated.”

The pair started working on ideas for a new system back in 1995 – focusing on trying to harness emerging technologies such as the internet and mobile data.

The team expanded over time, and BGAN owes its success to the effort and dedication of all those involved in the project.

Future success
And it was the move to develop a satellite version of the universal mobile telecommunications mobile broadband system – for people who are out of range of terrestrial services – which eventually proved pivotal to Inmarsat’s future success.

The team carried out painstaking research, working with external companies to create a flexible and efficient standard BGAN system – which could deliver high-speed data and voice services simultaneously – via satellite.

Alan said: “The result was a very capable system which can continue to be evolved and built on over time.”

Links: Immarsat, BGAN, Mobile Satellite Users Association

Researchers warn of nitrogen hazard to environment

Sunday, May 25th, 2008

While carbon dioxide has been getting lots of publicity in climate change, reactive forms of nitrogen are also building up in the environment, scientists warn. Almost all of us does not yet know much about nitrogen, but in many ways it is as big an issue as carbon, and due to the interactions of nitrogen and carbon, makes the challenge of providing food and energy to the world’s peoples without harming the global environment a tremendous challenge, as stated by University of Virginia environmental sciences professor James Galloway said in a statement. Read more on this article

Researcher Pushes Enormous Floating Solar Islands

Sunday, May 25th, 2008

solar island

Creating cheap, clean energy is a huge problem.

So, how’s this for a big solution: Swiss researcher Thomas Hinderling wants to build solar islands several miles across that he claims can produce hundreds of megawatts of relatively inexpensive power.

He’s the CEO of the Centre Suisse d’Electronique et de Microtechnique, a privately held R&D company, and he’s already received $5 million from the Ras al Khaimah emirate of the United Arab Emirates to start construction on a prototype facility in that country.

While limited information is available on the solar islands website, Hinderling laid out his scheme at The Oil Drum, a well-known blog about energy. Hinderling estimates that an island a mere mile across could generate 190 megawatts of power with a breakeven price point of $0.15 a kilowatt hour, or about twice current electricity prices in the United States.

solar island 2 The islands will consist of a plastic membrane loaded up with solar concentrating mirrors floating above the water. The mirrors are used to heat liquid to turn it into steam, which drives a turbine that generates energy.

On land, this type of electricity generation is fairly well known. So-called solar thermal plants are emerging as a leading alternative to fossil fuel power plants for future energy generation, with two of Google’s three alt-energy investments coming in solar thermal companies.

But why head to the ocean to create solar thermal power? Hinderling claims that the entire platform can be turned to align with the sun, generating maximum efficiency without a complicated tracking system. The company’s production schedule has it splashing a 1500-foot in diameter platform into the water at the end of 2010.

Mark Bollinger, a renewable energy researcher at Lawrence Berkeley National lab, thought it would be possible to create such an island, but questioned the viability of the enterprise.

“I’m sure it’s possible, but it seems a little bit out-there, just given where the technology is and how little of it has been developed on land,” Bollinger said.

From a feasibility perspective, he questioned the necessity of pushing solar thermal out to sea, where new variables like the waves could throw off precision-tracking of the sun’s rays.

“The reason you’d do that is if space was at a premium, but I don’t think it is, at least for solar thermal,” he said. “Where it works best is in the desert of the Southwest, and there’s a lot of land down there.”

Another big question Hinderling doesn’t address is transmission, i.e. how you get the power off the island and to the people. Luckily, offshore transmission options (.pdf) are already being explored for wind farms located out in the ocean. And Bollinger noted that there are ocean barges that already produce power for “load-constrained” areas of the Northeast.

All that said, we can’t help but think that this would be a great way to power The Seasteading Institute’s floating ocean colonies.

Source: Wired