Method and system for improving a communication range and reliability of a soil sensor antenna

• US 8,374,553 B1
• Filed: 01/31/2010
• Issued: 02/12/2013
• Est. Priority Date: 02/03/2009
• Status: Active Grant

• Current Assignee: Green Badge, LLC
• Original Assignee: Green Badge, LLC
• Inventors: Campbell, Jeffrey, Sohrabi, Kathy, Karmel, Clayton R.
• Primary Examiner(s): GONZALES, APRIL GUZMAN
• Application Number:
  US12/697,258
• Time in Patent Office: 1,108 Days
• Field of Search: 455/66.1, 702/22, 702/2, 250/255, 356/366, 356/337, 356/303, 356/326, 700/284, 137/78.3
• US Class Current: 455/66.1
• CPC Class Codes: A01G 25/167 Control by humidity of the soil itself or of devices simulating soil or of the atmosphere; Soil humidity sensors
• CPC Class Codes: G01N 33/24 Earth materials G01N33/42 takes precedence
• CPC Class Codes: H04W 4/00 Services specially adapted for wireless communication networks; Facilities therefor
• CPC Class Codes: Y10T 137/189 Soil moisture sensing

Abstract

A wireless sub-surface soil sensor having a switchable configuration antenna that can be optimized for various soils is disclosed herein. The wireless sub-surface sensor also measures the moisture and salinity of a material. The wireless sub-surface sensor preferably includes a cover for protecting circuitry of the sensor. The wireless soil sensor is designed to be buried underground and to transmit to above ground receivers, which provide feedback for configuring the switchable antenna.

Claims

1. A method for improving a communication range and communication reliability of an antenna for a wireless soil sensor buried below the surface of a land area, the method comprising:

activating a wireless sensor;

measuring a plurality of soil electrical properties for the land area;

transmitting data from the wireless sensor to at least one receiver above the surface of the land area at a plurality of switchable antenna configurations;

monitoring a signal property of each transmission of data for each of the plurality of switchable antenna configurations;

repeating the above steps every predetermined number of sensor transmission cycle;

creating a map of the signal property for the plurality of switchable antennal configurations;

providing the map to each of a plurality of sensor nodes;

determining from the map the most favorable antenna configuration for the position of the node;

configuring the sensor node to the most favorable antenna configuration; and

transmitting data from the node.

2. The method according to claim 1 wherein the predetermined number of sensor transmission cycles is sixty.

3. The method according to claim 1 wherein the plurality of soil electrical properties comprises soil conductivity and soil dielectric constant.

4. The method according to claim 1 wherein the map is a two dimension map of soil conductivity and soil dielectric constant.

5. The method according to claim 1 wherein the signal property is received signal strength.

6. The method according to claim 1 wherein the land area is a golf course.

7. A system for improving a communication range and communication reliability of an antenna for a wireless soil sensor buried below the surface of a land area, the system comprising:

a plurality of wireless sub-surface sensors, each of the plurality of wireless sub-surface sensors capable of monitoring soil conductivity and soil dielectric constant, each of the plurality of wireless sub-surface sensors comprising a configuration switchable antenna for transmitting and receiving data to and from above ground, a processor and a battery, wherein the data comprises the soil conductivity and soil dielectric constant;

a receiver for receiving and transmitting data to the plurality of wireless sub-surface sensors, the receiver also monitoring signal strength from each of the plurality of wireless sub-surface sensors based on a plurality of switchable antenna configurations; and

a control engine, the control engine receiving the data from the receiver, the control engine having a processor configured to create a two dimensional map of the signal property for the plurality of switchable antenna configurations based on soil conductivity and soil dielectric constant.

8. The system according to claim 7 wherein each of the plurality of wireless sub-surface sensors comprises a first plurality of sensors and a second plurality of sensors, each of the first plurality of sensors positioned within an upper soil and capable of monitoring an upper soil conductivity and an upper soil dielectric constant, each of the second plurality of sensors positioned within a lower soil and capable of monitoring a lower soil conductivity and a lower soil dielectric constant.

9. The system according to claim 7 wherein each of the plurality of wireless sub-surface sensors transmits and receives data at a communication frequency of 2.4 GigaHertz.

10. The system according to claim 7 wherein each of the plurality of wireless sub-surface sensors comprises a probe conducting structure, a circuit comprising a high frequency oscillator for applying a electrical stimulus to the probe structure, a reference capacitor connected in series to the high frequency oscillator, and a voltage meter located between the high frequency oscillator and the reference capacitor.