RFID and Temperature Sensing Utilizing SAW Technology

RF SAW, Inc. produces Radio Frequency Identification (RFID) products that operate in the 2.45 GHz globally legal frequency band. RFSAW is exploiting a fundamentally new type of RFID system based on Surface Acoustic Wave (“SAW”) devices, a reliable, low-cost, well established RF wireless technology. The Company has invented, patented and successfully developed this new system whose core element is the “Global SAW Tag”. This new approach provides superior solutions for our target markets that include supply chain, asset management, health care, transportation security, food-chain safety, healthcare, military, and governmental applications. RFSAW’s product family includes tags, readers, antennas, and applications software in a variety of configurations.

RF SAW Technology
The unique physics of SAW ID chips solves major RFID issues and achieves: a) reliable reading at large separation between tag and reader, (b) surmounting the tendency of liquids and metals to block reading signals, and (c) commercial full pallet reading which is a vitally important RFID capability. In many applications, SAW tag read range is sufficiently large so that our passive tags can replace high-cost battery-powered active tags.

SAW-based RFID systems have the inherent ability to measure tag position, direction of travel, and tag temperature, which are costly or difficult to implement with competing technologies. Furthermore, SAW tags can withstand security and safety related processes that involve elevated operating temperatures, high energy x-rays, or gamma ray sterilization.

The Global SAW Tag uses an inherently lower cost chip in combination with a smaller, less costly tag antenna, which results in a substantial cost advantage over competing IC-based tags.

In addition, overall system cost is optimized by placing key signal processing functions such as anti-collision (i.e., reading multiple tags simultaneously) in the reader unit instead of the tag. Anti-collision is enabled by multiple-access spread-spectrum signaling that also leads to high-speed reading. Spread-spectrum provides substantially higher interference resistance and achieves spectrum compatibility with other radio frequency systems and RFID readers.

Global SAW Tag:
* Overcomes the numerous limitations of IC based RFID chips including power requirements and performance limitations.
* Can operate legally worldwide
* Is significantly more cost-effective than semiconductor RFID chips;
* Provides a practically unlimited number of identification codes for SAW ID tags.
* Provides superior read range while maintaining high-speed and accurate readings.
* Finally makes possible the hoped for technology to truly transcend bar codes.

SAW RFID Operation:
The reader emits a radio wave pulse that is directly converted into a nanoscale Surface Acoustic Wave on the SAW chip surface by the “IDT” (interdigital transducer). That acoustic wave travels past a set of wave reflectors to produce uniquely encoded acoustic wave pulses, which travel back to the IDT. The IDT converts those pulses into an encoded radio wave reply signal that is sent back to the reader. The SAW chip operates using the piezoelectric effect and does not require DC power. (Note: chip size is not to scale.)