The tags were tested in a lab to simulate the environment in which they would operate—namely, helicopters, as well as large and small fixed-wing aircraft—to determine whether they met the requirements of the DOD Interface Standard 461F (an RF standard used by the U.S. military, according to Zentner). In theory, he says, a tag's power supply could generate RF
noise. All of the vendors' tags now operate within the military's 461F specifications, though at least one model needed to be modified before it could pass the test. Helicopters are the greatest risk for this interference, he adds, since they have more apertures (openings through which RF transmissions could leak out) than other small or large aircraft.
Ultimately, Zentner says, the
RFID hardware provided no interference concerns. "RFID devices seem fairly innocent," he states. The tests were undertaken in a metallic room without actual aircraft, and the tags were set to continually transmit. The researchers measured the electromagnetic fields that resulted.
|
|
Unisys' Michael Saunders
|
For Savi, says Mark Nelson, the company's director of corporate communications, "it means that we now have an authoritative source that has tested active RFID at the 433 MHz range, and has found that it does not interfere with the aircraft that is carrying the tags. This certification can now be used to show civilian airlines that the tags are safe to carry."
The DOD and other government agencies use aircraft as a means of transporting RFID-tagged cargo. In the case of the 18000-7 tags, most will be utilized on shipping containers that would be transported by ocean, so few will actually be placed within an aircraft. However, the
EMI certification indicates the tags can be safely transported by air, if necessary.
The switch to
ISO 18000-7 hardware is opening up opportunities for the commercial use of active RFID technology for tracking supplies that will be transported to or by the military, says Patrick Burns, the president of the
Dash7 Alliance, a coalition of 30 companies and organizations from multiple industries focused on supporting the adoption of the
ISO 18000-7 standard. The alliance was launched this year, in part due to the DOD's plans for the RFID-III contract using ISO 18000-7 (see
Dash7 Alliance Seeks to Promote RFID Hardware Based on ISO 18000-7 Standard).
The DOD has been an advisor to the alliance, helping the organization to develop testing and certification procedures for
interoperability of the technology, as well as planning the next stages, including
encryption plans and outreach work to publicize the active RFID standard. Products purchased by the DOD in this order have earned Dash7 1.0 Interoperability Certification, indicating they have successfully completed baseline
interoperability testing for DOD-specific deployments.