Nortech Radio Comms » July 2014

Monthly Archives: July 2014

Telecommunications

What Is an Ultrasonic Transducer?

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Without giving too much about this earpiece article, but I found it remarkable and relevant to what I’m currently doing.

An ultrasonic transducer is an electrical component that converts ultrasonic sound waves beyond the range of human hearing into alternating current (AC) or direct current (DC) electrical signals that are then transmitted or recorded. Usually such devices are built upon crystals that demonstrate a piezoelectric effect, which conduct electrical current in response to mechanical stress or vibrations. The crystals have directly proportional output to the strength of the input sound wave or stress, and this makes them useful measuring devices as an ultrasonic transducer.

ultrasonic transducerApplications for ultrasonic transducer-based electronics included use in early television remote controls as signal devices, and, as of 2011, in anemometers used by weather stations to monitor wind course and speed. They are used in industrial applications to monitor the level of fluid in a tank, and in modern-day automobiles as of 2011 for echo location sensors to indicate objects in close proximity to the path of a vehicle that is backing up or pulling into a garage. Since an ultrasonic transducer can also play the role of an ultrasonic transmitterthrough input electrical power, they offer the capability of a primitive type of sonar in many cases. Sound waves can be reflected off of a surface and the distance to that surface measured by the time and frequency of the wave that bounces back.

Electrical devices that convert one form of energy to another, like ultrasonic sensors, often have widespread applications in electronics and industry. Many diverse uses for the ultrasonic transducer now exist, including in environmental controls for buildings, such as in humidifiers where they vaporize the surface of the water, and in burglar alarms to detect objects moving within an otherwise clear path. Ultrasonography also relies on the principle of an ultrasonic transducer in medicine, where sound waves of 1 to 30 megahertz are employed to remotely generate imagery for the state of muscles, internal organs, and blood vessels in the human body, as well as the state of a fetus during pregnancy.

Since the era of the 1940s, the ultrasonic transducer has been incorporated into testing equipment to detect flaws in a range of sonar-related applications. They can be used to find fine cracks, voids, or porous sections in concrete and building foundations, damaged or fractured metal welds, and flaws in other materials such as plastic, ceramic, and composites. The devices are versatile because the sound waves that they emit will be affected by any medium, whether liquid, solid, or gas. With a detector used to measure gas status, however, an intermediate gel is usually placed between the gas and the ultrasonic transducer, as sound waves are otherwise poorly conducted and recorded in a gas medium.

The field of flaw detection for ultrasonic technology is broken down into five different types of transducer designs: contact, angle beam, delay line, immersion, and dual element transducers. Contact transducers have to have close contact proximity to what they are measuring, such as a stud finder in the building trade used to detect wooden beams behind walls. An immersion transducer is waterproof and placed in a fluid flow. Both angle beam and delay line forms of an ultrasonic transducer are used to measure welds and in conditions of high temperatures. The dual element transducer is simultaneously a transmitter and receiver for continuous monitoring of rough or potentially flawed surfaces.

2 way radio

DMR Tier III: the open standard for radio communications

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So i discovered this short article on the web and i was told that just posting it as the whole article is not the right thing, I got consent from the original writer and read up how to curate posts, so that is it…….i thought this was interesting as it highlights some of the highs and lows that I encountered when i was working within the business.

Private mobile radio is fast becoming an essential communications solution to support the operational needs of utilities companies, airports, oil and gas pipelines and emergency services.

When compared to public cellular services, it delivers improved coverage, reliability and resistance, contention, security, group communications and performance.

The digital landscape is crowded, though, with a number of public safety digital standards such as TETRA, P25 as well as low cost digital solutions including DMR (Digital Mobile Radio), dPMR (digital Private Mobile Radio), NXDN and PDT (Professional Digital Trunking).

DMR is coming out on top thanks to the open standard nature of DMR Tier III trunking, which is driving its emergence, ongoing development and adoption across global markets.

But do open standards matter? While open standards are less important in the small system market, they are critical to the long-term case for the radio system in the medium to large systems sector, and it is here that open standard DMR Tier III will dominate.

Essentially, DMR Tier III trunking features a control channel on each radio site and allocates traffic channels on demand making it frequency efficient and enabling a large number of users to share a relatively small number of channels. Radio sites can easily be inter-connected, usually using IP connections, making it possible to deploy systems ranging from a single site to hundreds of sites spread over a large geographical area.

The open standard way

The DMR standard includes the facility for implementers to provide ‘manufacturer extensions’, enabling manufacturers to provide proprietary features within the framework of the DMR air interface definition. This allows them to complement the standard set of DMR call functions with their specific facilities.

This has the advantage of enabling customers to request specific functionalities to support the manufacturer’s business operation needs and also enables them to provide innovative features that differentiate their solutions from others implementing the same standard.

One disadvantage to this offering is that interoperability can only be possible for those features that are fully defined by the standard and that customers using manufacturer extensions are effectively locked in to a single manufacturer solution rather than enjoying the vendor choice that a standard enables.

To address the pros and cons, the DMR Association (DMRA) has struck a balance between robustness and cost with their interoperability process, which focuses on testing the conformance of products against the published standard that describes the over-air signalling. The DMRA facilitates testing between a terminal manufacturer and an infrastructure manufacturer, and the two parties carry out the testing against a standard test specification. Test results and logs of all messages sent over air are recorded during the testing and then are inspected by one or more independent third parties during a detailed review meeting. Only after the independent third parties are satisfied that the equipment under test has conformed to the open standard specification is an interoperability certificate issued.

Ongoing standards development

Whilst this facility can be useful, extensive use of manufacturer extensions would call into question whether DMR was a standard that delivers interoperability (and therefore vendor choice) or whether it results in proprietary solutions rather than following an open standard.

The answer to this lies in the work of the DMR Association. The DMRA has a technical working group – made up of competing manufacturers – who collaborate to ensure the standard succeeds. Any proprietary features from the manufacturers, which are believed to have wide market appeal or have useful features the standard doesn’t yet specify, are debated in the group. They are then developed to further advance the standard to the benefit all of the manufacturers and indeed the customers who choose to implement DMR technology.

The DMRA is further developing the standard to meet future market demands by identifying important new features and ensuring these are developed and included in new releases of the ETSI standards.

The future of DMR Tier III

Open standards are critical to providing long-term support and stability to customers. The adoption of the standard by a critical mass ensures its longevity over other similar competing technologies that have lower levels of support by offering the market vendor choice and maintaining low costs.

Is DMR Tier III radio communications’ open standard for the future? Yes. Due to DMRA’s authority, the robust and well-supported interoperability programme and the long-term commitment of a large number of manufacturers, it is emerging as the most successful low cost digital technology for complex projects – and therefore the open standard that no other private mobile radios can contend with.

Source – http://www.telecomstechnews.com/news/2014/apr/25/dmr-tier-iii-open-standard-radio-communications/

Technology News

A Martian Tribute

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Professor Steve Squyres of New York’s Cornell University has named a beautiful piece of Martian landscape after his recently departed friend and colleague, the British scientist Colin Pillinger.

Squyres, who leads the team in charge of NASA’s Mars Exploration Rover, felt that naming a portion of the red planet in honour of his friend would be a fitting tribute. 

In a column for BBC News, Squyres wrote, “When I heard the news of Colin’s death, I knew immediately that we had to name a place on Mars after him. And by very good luck, Opportunity was at that moment approaching one of the most beautiful places I’ve ever seen on Mars. We named it Pillinger Point”.

Pillinger Point is situated on the Western rim of Endeavor Crater, a 22 km impact crater on the surface of Mars. The location offers perhaps the best view yet seen of the Martian landscape.

“I like to think that Colin would have enjoyed this view, and I hope that our image of it will help honour his memory”, wrote Squyres.

colin pilingerColin Pillinger, who died in May of this year of a brain haemorrhage, after nearly a decade of battling multiple sclerosis, was perhaps best known as the brains behind the unsuccessful Beagle 2 mission to Mars, which took place during 2003.

The unmanned probe was designed to seek out life in the Martian wilderness. Although the mission ultimately ended in failure, Squyres is optimistic regarding The Beagle’s final legacy. “What they (Pillinger and his team) did do, though, was energize the public in Britain and around the globe in a way that few scientific explorers have matched”. He writes.

Born in 1943, Colin Pillinger worked first for NASA, analyzing lunar samples and later at Cambridge University and then The Open University. In 2000, he had an asteroid named after him and in 2003; he was awarded a CBE by the Queen.

Later, in 2011, Pillinger was awarded the prestigious Michael Faraday Prize.

Writing of his friend and kindred intellect, Steve Squyres simply says, “Colin was a force of nature, and his enthusiasm for Mars exploration was unparalleled. So I think that Beagle 2’s greatest legacy, and part of Colin’s, is surely the thousands of young people who were inspired to pursue careers in science, in engineering, and in technology, and to follow in Colin’s footsteps”.

It is a fitting tribute for a man who spent his life and career looking toward the stars.

SOURCES

http://www.bbc.co.uk/news/science-environment-28033648

http://en.wikipedia.org/wiki/Colin_Pillinger

2 way radio

The IC-4088SR: A PMR 445 Licence Free Radio

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So to carry on my run of articles on this blog, I have planned to share one of my favorite posts this week. I used to be cautious to add it to this website as I really didn’t wish to offend the original author, but I hope he/she is glad that I loved reading their work and wanted to share it with my readers.

PMR446 Handheld Transceiver

Designed to meet the demands of the licence free PMR 446 service, the IC-4088SR builds on its predecessor’s functionality, features and operating performance.

Featuring a high level of flexibility, the IC-4088SR allows instant communication between members of a group in and around buildings and over short distances. This makes it the perfect tool for keeping in touch with friends, family and work colleagues whilst in close proximity to them. The applications for the PMR446 service are almost limitless and the IC-4088SR would be suitable for camping, golf, catering, use in sports centres, on building sites, catering, events management, neighbourhood watch, factories, farms etc. What’s more it is water-resistant making it ideal for rambling, trekking, or for use on inland waterways etc.

An optional external charger socket or cigarette lighter lead allows you to charge and operate the IC-4088SR allowing you to use the IC-4088SR when and whenever you like. 

The IC-4088SR has all the hallmarks of a quality product. It is well designed, easy to use and very robust. Its strong body makes it ideal for outdoor activity enthusiasts, for example. In fact the IC-4088SR is ergonomically designed and there are an absolute minimum number of switches making operation quick and intuitive. The large, easy to read LCD shows operating information at a glance with clear status icons such as ‘low battery’ and ‘timer’ that are easily recognisable. 

In addition to its ease of use and aesthetic design the IC-4088SR is packed full of communication features that provides the user with a high level of usability and convenience. Among these useful functions are a simple voice scrambler that will provide secure private communication and a handy ‘Automatic Transponder’ function which automatically warns you if the other radios are out of range. 

Other useful operating functions include a call ring function, which allows you to send a ring tone when calling another party – similar to using a mobile phone. Ten different ring types can be selected from. To ensure clear communications with other radios, you can select from 8 different radio channels and 38 different group codes, giving more than 300 different combinations to choose from. A Smart Ring function is also included which lets you know whether your call has got all the way through.

The IC-4088SR transceiver is available with charger and four rechargeable batteries. Two commercial multi-packs are also available.

 

  • Rugged construction and high performance antenna
  • External DC power jack
  • Built-in voice scrambler
  • Simple to use for everyone
  • Economical three alkaline cells
  • Splash resistant construction
  • Built-in CTCSS encoder and decoder
  • Automatic transponder system
  • Smart-ring function
  • Call-ring function
  • Power save function
  • Low battery indicator
  • Automatic power-off timer (0.5–2 hours)
  • Scan function
  • PTT hold function
  • Variable time-out-timer (1–30 minutes)