DASH7 is a new wireless sensor networking technology using the ISO/IEC 18000-7 standard for active RFID, operating at in the 433 MHz unlicensed spectrum.

DASH7 provides multi-year battery life, range of up to 2 km (potentially farther), low latency for tracking moving objects, small protocol stack, sensor and security support, and data transfer of up to 200 kbit/s. DASH7 is the name of the technology promoted by the non-profit consortium called the DASH7 Alliance.

What is The DASH7 Alliance?

The DASH7 Alliance was formed to advance the use of DASH7 wireless data technology by developing extensions to the ISO 18000-7 standard, ensuring interoperability among devices, and educating the market about DASH7 technology. Formed in 2009, the Alliance now has more than 20 members. Manufacturers, systems integrators, developers, regulators, academia, and end-users all work together to promote the use of DASH7 technology in a wide array of industries and applications. (source www.dash7.org)

The goals of the DASH7 Alliance are to:

• Develop improvements and extensions to the ISO 18000-7 standard
• Work to ensure that products claiming DASH7 capabilities comply with DASH7 specifications
• Encourage the development of products using DASH7 technology
• Educate consumers and enterprises globally about DASH7 technology

The DASH7 protocol combines a low power wireless sensor networking (like Zigbee) with RFID. It operates in the 433 MHz unlicensed spectrum, communicates at 100 kbps, penetrates concrete and water, and connects over long distances at low power.

The DASH7 protocol features:

• Multi-kilometer range and excellent penetration of walls, floors, and things made of water
• Extremely low power draw (measured in microwatts) and multi-year battery life
• A maximum bitrate of 200kbps
• Supports tag-to-tag or “multi-hop” communications, sensors, and public key encryption
• Multi-channel architecture for real-time locating capability
• Extremely low latency for tracking moving objects
• Operation in the license-free and globally available 433 MHz spectrum
• “Out of the box” interoperability using a single global frequency
• The brand given to the ISO 18000-7 standard for active RFID

]]> http://blog.testequipmentconnection.com/dash7-and-rfid/feed 0 http://blog.testequipmentconnection.com/low-frequency-array-lofar-so-far http://blog.testequipmentconnection.com/low-frequency-array-lofar-so-far#comments Tue, 15 Jun 2010 14:22:04 +0000 http://blog.testequipmentconnection.com/?p=860 Read More →]]> LOFAR started as a new and innovative effort to force a breakthrough in sensitivity for astronomical observations at radio-frequencies below 250 MHz. The LOw Frequency ARray is a multi-purpose sensor array. Its main application is astronomy at low frequencies (10-250 MHz) but also has geophysical and agricultural applications. Its heart is currently being assembled in the Northeast of the Netherlands and spreads over the whole country and over whole Europe.

LOFAR uses a large number of low-cost sensors (antennas, geophones and more) and relies on broad-band datalinks and advanced digital signal processing to implement the majority of its functionality in (embedded) software.

LOFAR will be the first large radio telescope system, wherein a huge amount of small sensors are used to achieve its sensitivity instead of a small number of big dishes.

The main reasons for this are:

• For the low frequencies involved in LOFAR traditional telescopes would be very large and hence costly.
• Pointing can be done electronically, without using move-able parts and hence saving on maintenance costs.
• It enables pointing in multiple directions at the same time.
• It provides operational flexibility (e.g. rapid switching between observations is possible).

From the LOFAR Site:
Her Majesty the Queen will open the largest radio telescope in the world, LOFAR, on Saturday afternoon 12 June 2010 in Borger-Odoorn (Drenthe). The new LOFAR telescope has been built according to a completely new concept. No large dishes are used, but large numbers of small antennas.

7,000 antennas are spread over 44 fields in the North of the Netherlands and from Sweden to France and from the UK to the East of Germany. Glass fibres connect the antennas with a supercomputer at the University of Groningen’s Computer Centre. In this way, a giant telescope is formed with a diameter of one hundred to one thousand kilometres.

The telescope researches, among other things, the earliest Universe, cosmic particles and magnetism in the Milky Way and other galaxies. LOFAR is also used for research in the area of geophysics, precision agriculture and ICT. While the antennas observe the sky, underground sensors collect date about the structure of the Earth. These data contribute to better models for the Earth, water management and gas exploitation. (source www.lofar.org)