Soil measurement system using wireless signals

A soil measurement method, comprising:

• mounting a plurality of subterranean antennas into a subterranean environment at different depths in the subterranean environment, the plurality of subterranean antennas electronically connected to a radio receiver;
• emitting a wireless signal at a predetermined bandwidth in a predetermined spectrum via a wireless radio transmitter;
• receiving the wireless signal at each of the plurality of subterranean antennas in an array, each of the plurality of subterranean antennas receiving the wireless signal at a respective point in time;
• determining, via a processor, a relative time of flight of the received wireless signal between the plurality of subterranean antennas at the respective point in time;
• estimating, via the processor, a soil permittivity based on the determined relative time of flight;
• and
• outputting the estimated soil permittivity via a display or communication interface communicatively coupled to the processor.

A material measurement system, comprising:

• a material surveying device comprising a wireless radio transmitter configured to emit a wireless signal at a predetermined bandwidth in a predetermined spectrum;
• a radio receiver;
• a plurality of antennas in an array electronically connected to the radio receiver and configured to be mounted in a material at different depths in the material, wherein each of the plurality of antennas is configured to receive the wireless signal at a respective point in time;
• and
• a processor configured to:
• determine a relative time of flight of the received wireless signal between the plurality of antennas at the respective point in time;
• and
• estimate a permittivity of the material based on the determined relative time of flight.