Invention Delivers Pure Location Signals for Q-Track

Minimum coupling antennas enable Q-Track receivers to precisely measure all three magnetic field components without cross-contamination between signals.

Huntsville, AL June 12, 2018 — The U.S. Patent Office today awarded U.S. patent 9,997,845 for an “Embedded symmetric multiple axis antenna system with isolation among the multiple axes,” to Q-Track inventors, Hans G. Schantz, Christopher D. Pittman, James L. Richards, and Stephen A. Werner.

The Q-Track inventors discovered how to implement compact magnetic antenna arrays capable of detecting all three components of the magnetic field. Mutually orthogonal three-axis electrically-small magnetic antenna arrays are of great interest for field probes, direction finding, and location systems. Orthogonality does not guarantee minimum coupling between two or more antennas, however. A poorly designed antenna array will exhibit mutual coupling even between orthogonal elements, confounding the independence of the measurements. Q-Track CTO, Dr. Hans G. Schantz, presented a paper on this invention, “Minimum Coupling Antenna Arrays,” in 2015 at the Antenna Applications Symposium at Allerton Park, Monticello, IL.

The invention delivers “pure” signals with isolation of 50 to 60 dB between components by arranging orthogonal antennas in a symmetric, compact orientation. The arrangement assures minimum coupling conditions are met between any pair of antennas. “This new patent win cements Q-Track’s position as a leader in near-field wireless systems in general and indoor location systems in particular,” explains Q-Track CEO, Stephen A. Werner. “This invention allows Q-Track to make the precise measurements that enable our real-time location systems (RTLS) to deliver 40 cm accuracy in support of training, security, safety, and a host of other indoor location applications.”

About Q-Track:

Q-Track Corporation ( offers solutions that provide “Knowing Where, Anywhere” for a growing range of industrial real-time location applications. The company’s patented Near-Field Electromagnetic Ranging (NFER®) systems employ a unique low-frequency, long-wavelength radio signal to achieve highly accurate (40 cm rms) indoor location results even in complicated non-line-of-sight environments. NFER® Real Time Location Systems enable “Dosimulation™,” a radiation worker training system deployed in a third of U.S. nuclear plants. Q-Track also offers proximity detection and collision avoidance systems that protect people from cranes, robotic material handling equipment, and forklifts at a variety of manufacturing plants nationwide, as well as location systems that enhance military training by precisely locating soldiers in training ranges extending through multiple buildings and across tens of thousands of square meters (hundreds of thousands of square feet).

Q-Track is a privately-held company located in Huntsville, AL. The company’s research and development was supported by private investors and funding from the Department of Homeland Security, the National Science Foundation, the Defense Advanced Research Projects Agency, and the National Institutes for Health.

For More Information Contact:

Stephen Werner
(256) 489-0075