Abstract: The present disclosure provides a device and method for producing low-frequency magnetic-field signals to enable long-range wireless communication through conductive media. The magnetic-field signals can be generated by mechanically moving permanent magnets. In some examples, transmitters are capable of transmitting signals in the ultra-low and very-low frequency ranges (e.g., 100 Hz-30 kHz), utilizing a small amount of power.

Abstract: The present disclosure provides a device and method for producing low-frequency magnetic-field signals to enable long-range wireless communication through conductive media. The magnetic-field signals can be generated by mechanically moving permanent magnets. In some examples, transmitters are capable of transmitting signals in the ultra-low and very-low frequency ranges (e.g., 100 Hz-30 kHz), utilizing a small amount of power.

Abstract: An antenna device includes a dielectric layer, an electrical ground layer carried on one side of the dielectric layer, and an antenna arrangement carried on another side of the dielectric layer. This arrangement includes two parasitic microstrip elements and a microstrip signal element. The signal element is structured to radiate an electromagnetic signal in response to application of a corresponding electrical communication signal. The parasitic antenna elements extend along opposing longitudinal sides of the signal element and each includes an adjustable component operatively connected between two microstrips. The adjustable component is structured to selectively adjust operable length of a selected one of the parasitic antenna elements to change a maximum radiation direction of the antenna device.