Wireless sensor nets hunt for full 'killer' apps

Wireless sensor networks (WSNs) are not being fully utilized in commercial markets due to the lack of a 'killer application' to drive interest, a Plextek-led report for U.K. communications industry regulator Ofcom said.

The 10-month study was commissioned to examine technology developments in WSNs, along with market growth scenarios and what would be the spectrum implications.

Plextek worked with the University of St. Andrews and TWI Ltd, a Cambridge-based independent research and technology organization, on the research, which found that it is the traditional sensing applications that are currently commercially exploiting the advantages of WSNs.

The popularity of WSNs
The report suggested that WSNs may become more widely deployed over the next three to five years, with systems continuing to adopt existing license-free bands including 13.56MHz, 433MHz, 868MHz and 2.4GHz. The main issue for WSNs will be the band crowding, especially 2.4GHz with the increased Wi-Fi use.

Ofcom commissioned the study as part of its "Tomorrow's Wireless World" R&D program into the future of communications technology.

"Our research produced some very interesting conclusions," said Steve Methley, senior consultant, Plextek. "The lack of a killer application may be due to limiting factors such as current cost of wireless nodes and lack of understanding or experience by end users, especially regarding 'real-world' reliability," he added.

Methley noted that there is also a need for further improvements in batteries and energy scavenging technologies.

Suggested strategies
"One possible movement toward a killer application is to let major systems integrators get involved," said Methley. "Such players will increasingly come on board when there is a need to take a professional approach to defining, installing and maintaining substantial wireless sensor networks," he added.

The study suggested that while existing unlicensed spectrum can adequately support WSNs, "a dramatic increase in use could prove problematic."

"Typical radio protocols such as the popular 802.15.4 standard are designed to be polite and to check for clear channels before transmitting," it noted. This may become a problem when bands become crowded. The standard suffers because of its politeness in the face of increasing Wi-Fi usage, particularly in the streaming applications. This may lead to the appearance that WSNs are unreliable, an important issue as the perception of unreliability is one of the key barriers identified for WSN adoption.

- John Walko
EE Times Europe