A radical reflection on RFID.
Omni-ID's revolutionary plasmonic technology was inspired by nature. It mimics the way the wings of certain butterflies reflect and transmit light to produce their distinctive markings. In the case of our tags, it is RF energy—not light—which is reflected. The result is an amazingly accurate RFID tag, which is reliable on all materials.
Omni-ID's revolutionary plasmonic technology was inspired by nature. It mimics the way the wings of certain butterflies reflect and transmit light to produce their distinctive markings. In the case of our tags, it is RF energy—not light—which is reflected. The result is an amazingly accurate RFID tag, which is reliable on all materials.
Why RFID? The reliability problem.
Keeping track of your organization's assets and stock levels is a huge management challenge—and getting it right requires a major commitment.
RFID technology offers an amazing array of real-world advantages for a wide range of applications, from supply chain management to asset tracking. Unlike bar-coding, RFID tagging does not require line-of-sight or limit the simultaneous reading of multiple tags. RFID enables you to run the tags past a reader and your data is returned.
Seem too good to be true? Unfortunately, for some installations, it is. A basic RFID tag in less than ideal conditions—and without the advantage of Omni-ID's innovative technology—averages read rates of 60-70%. That basic tag may also experience failure rates that approach 90% in some environments. Not surprisingly, this reliability problem is a major concern in any RFID implementation.
For some installations, such as data centers (where systems uptimes are often 99.99% guaranteed), reliability is a way of life. Unread tags represent lost or incorrect information-and increased costs. The logical question is, "Can anything be done to enhance the read rates of RFID tags?"
Fortunately, the answer is yes. Omni-ID tags are built on a non-intuitive technology that makes it possible to read RFID tags reliably over 99.999% of the time. However, before you can fully appreciate the elegance of the Omni-ID solution, it is important to understand the leading causes of RFID-read failures: metals and liquids.
Addressing the issue of metals and liquids.
RFID relies on radio frequency (RF) waves. The problem is that metals reflect those waves and water absorbs them. The obvious implication is that both media prevent data from reaching, or returning, from an RFID tag. Unfortunately, few RFID-appropriate applications exist in which either metals or liquids, or both, are not present.
In the case of metals, refection is a double-edged sword. Reflection can be extremely beneficial, allowing RF signals to bounce around materials that would otherwise block their reception. However, reflected waves can also be a source of interference that can decrease read ranges and tag performance. Compounding this is the fact that metal takes many forms; foil bags may be obvious, but rice, with its high iron content, is not.
The opposite of reflection is absorption. Liquids, and particularly water, can absorb RF waves—undermining RFID tag performance and reliability. Not only can a liquid block direct radiation, it can also absorb constructive reflection. The result is that the presence of a liquid, such as water, even indirectly located, can dramatically decrease RFID reliability. It is an insidious problem, too, since liquids are present in many materials: green wood in a shipping pallet, high moisture content in a ream of printer paper, and any food product with liquid content.
Metals and liquids also cause problems for standard RFID antennas—devices sized and designed for a specific tag to optimally receive signals in the 800—1,000 MHz frequency range. The proximity of the metal to the tag adds an additional reactance to the tag's equivalent circuit. This acts to grossly shift the resonant frequency of the antenna and destroys the impedance match between the antenna and the chip, rendering the tag unreadable, even at point-blank range.
In addition to reflecting and absorbing RF waves, water also causes dielectric loading. When an RF wave enters water, it slows down and its wavelength is reduced considerably. The result is that the dipole becomes too large, relative to this reduced wavelength, and the tag no longer works efficiently at RFID frequencies.
Clearly, the reliability of conventional RFID tags is challenged in the presence of metals and liquids. The problems only get worse in applications that include both materials. Omni-ID has addressed these problems with a technology that redefines the reliability of RFID in harsh conditions.
RFID technology offers an amazing array of real-world advantages for a wide range of applications, from supply chain management to asset tracking. Unlike bar-coding, RFID tagging does not require line-of-sight or limit the simultaneous reading of multiple tags. RFID enables you to run the tags past a reader and your data is returned.
Seem too good to be true? Unfortunately, for some installations, it is. A basic RFID tag in less than ideal conditions—and without the advantage of Omni-ID's innovative technology—averages read rates of 60-70%. That basic tag may also experience failure rates that approach 90% in some environments. Not surprisingly, this reliability problem is a major concern in any RFID implementation.
For some installations, such as data centers (where systems uptimes are often 99.99% guaranteed), reliability is a way of life. Unread tags represent lost or incorrect information-and increased costs. The logical question is, "Can anything be done to enhance the read rates of RFID tags?"
Fortunately, the answer is yes. Omni-ID tags are built on a non-intuitive technology that makes it possible to read RFID tags reliably over 99.999% of the time. However, before you can fully appreciate the elegance of the Omni-ID solution, it is important to understand the leading causes of RFID-read failures: metals and liquids.
Addressing the issue of metals and liquids.
RFID relies on radio frequency (RF) waves. The problem is that metals reflect those waves and water absorbs them. The obvious implication is that both media prevent data from reaching, or returning, from an RFID tag. Unfortunately, few RFID-appropriate applications exist in which either metals or liquids, or both, are not present.
In the case of metals, refection is a double-edged sword. Reflection can be extremely beneficial, allowing RF signals to bounce around materials that would otherwise block their reception. However, reflected waves can also be a source of interference that can decrease read ranges and tag performance. Compounding this is the fact that metal takes many forms; foil bags may be obvious, but rice, with its high iron content, is not.
The opposite of reflection is absorption. Liquids, and particularly water, can absorb RF waves—undermining RFID tag performance and reliability. Not only can a liquid block direct radiation, it can also absorb constructive reflection. The result is that the presence of a liquid, such as water, even indirectly located, can dramatically decrease RFID reliability. It is an insidious problem, too, since liquids are present in many materials: green wood in a shipping pallet, high moisture content in a ream of printer paper, and any food product with liquid content.
Metals and liquids also cause problems for standard RFID antennas—devices sized and designed for a specific tag to optimally receive signals in the 800—1,000 MHz frequency range. The proximity of the metal to the tag adds an additional reactance to the tag's equivalent circuit. This acts to grossly shift the resonant frequency of the antenna and destroys the impedance match between the antenna and the chip, rendering the tag unreadable, even at point-blank range.
In addition to reflecting and absorbing RF waves, water also causes dielectric loading. When an RF wave enters water, it slows down and its wavelength is reduced considerably. The result is that the dipole becomes too large, relative to this reduced wavelength, and the tag no longer works efficiently at RFID frequencies.
Clearly, the reliability of conventional RFID tags is challenged in the presence of metals and liquids. The problems only get worse in applications that include both materials. Omni-ID has addressed these problems with a technology that redefines the reliability of RFID in harsh conditions.
Ready to learn more? Read about how Omni-ID is shifting the paradigm.
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