Method of determining conditions on the ground using microradios

• US 8,160,497 B2
• Filed: 07/15/2011
• Issued: 04/17/2012
• Est. Priority Date: 01/20/2005
• Status: Active Grant

• Current Assignee: RadioFIDO LLC
• Original Assignee: BAE Systems Information and Electronic Systems Integration Incorporated (BAE Systems Plc)
• Inventors: Brommer, Karl D., Brommer, Tracey H.
• Primary Examiner(s): VO, NGUYEN THANH
• Application Number:
  US13/183,562
• Publication Number:
  US 20110269408A1
• Time in Patent Office: 277 Days
• Field of Search: 455/39, 455/40, 455/41.1, 455/41.2, 455/66.1, 455/343.1, 340/10.1, 340/10.3, 340/10.32, 340/10.4, 340/10.51
• US Class Current: 455/41.2
• CPC Class Codes: G06K 1/00 Methods or arrangements for marking the record carrier in digital fashion
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves
• CPC Class Codes: H02J 7/00045 Authentication, i.e. circuits for checking compatibility between one component, e.g. a battery or a battery charger, and another component, e.g. a power source
• CPC Class Codes: H04B 5/0037 for power transfer
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer
• CPC Class Codes: H10K 99/00 Subject matter not provided for in other groups of this subclass

Abstract

A microradio is provided with a hysteretic switch to permit an optimum range increasing charging cycle, with the charging cycle being long relative to the transmit cycle. Secondly, an ensemble of microradios permits an n² power enhancement to increase range with coherent operation. Various multi-frequency techniques are used both for parasitic powering and to isolate powering and transmit cycles. Applications for microradios and specifically for ensembles of microradios include authentication, tracking, fluid flow sensing, identification, terrain surveillance including crop health sensing and detection of improvised explosive devices, biohazard and containment breach detection, and biomedical applications including the use of microradios attached to molecular tags to destroy tagged cells when the microradios are activated. Microradio deployment includes the use of paints or other coatings containing microradios, greases and aerosols. Moreover, specialized antennas, including microcoils, mini dipoles, and staircase coiled structures are disclosed, with the use of nano-devices further reducing the size of the microradios.

Claims

1. A method of determining conditions on the ground, comprising the steps of:

dispersing an ensemble of microradios over the ground, each of said microradios including a rectifier, a capacitor to be parasitically powered, coupled to the rectifier, an oscillator coupled to the capacitor, a hysteretic switch coupled between the rectifier and the capacitor, a radiative structure coupled to both said rectifier and said oscillator to permit the charging of the capacitor in the microradio when a sufficient charge has been collected on the capacitor and then to discharge the capacitor to permit release of sufficient energy to power the microradio, whereby the microradios can be powered with relatively low levels of incident energy;

providing said microradios with sensors;

parasitically powering said ensemble of microradios;

receiving the emissions from said microradios; and

, demodulating the content thereof so as to record the parameters sensed by said sensors.

2. The method of claim 1, wherein the ground is covered with crops and wherein said sensors sense crop health.

3. The method of claim 1, wherein the sensors sense improvised explosive devices on the ground, whereby overflying the ground to parasitically power said microradios and receiving the outputs therefrom determines the presence of improvised explosive devices.

4. The method of claim 1, and further including the step of causing the ensemble of microradios to operate coherently so as to afford an n² power advantage.

5. The method of claim 4, and further including overflying the ground with a satellite and detecting signals from said microradios at satellite heights, whereby satellite surveillance of the ground is achieved when using coherent processes.

6. The method of claim 5, wherein said ensemble of microradios is parasitically powered by naturally-occurring energy in the environment.

7. The method of claim 1, and further including the step of projecting energy towards said ensemble of microradios from a low-flying vehicle, thereby to assist in the parasitic powering of said microradios.

8. The method of claim 1, and further including the step of coating each of said microradios with a conductive adhesive coating.

9. The method of claim 1, and further including the step of providing groups of said ensemble of microradios with a coding system such that the microradios respond to different codes, and further including the step of transmitting to said ensemble of microradios an access code that addresses selected groups of microradios according to the code.

10. The method of claim 9, and further including the step of providing batches of said microradios with a predetermined serial number, thus to identify a microradio when it transmits after having been parasitically powered.

11. An apparatus comprising a sensor and a microradio positioned on or embedded in an object, wherein the microradio is charged by external energy, reads the sensor and transmits to an interrogator, each of said microradios including a rectifier, a capacitor to be parasitically powered, coupled to the rectifier, an oscillator coupled to the capacitor, a hysteretic switch coupled between the rectifier and the capacitor, a radiative structure coupled to both said rectifier and said oscillator to permit the charging of the capacitor in the microradio when a sufficient charge has been collected on the capacitor and then to discharge the capacitor to permit release of sufficient energy to power the microradio, whereby the microradios can be powered with relatively low levels of incident energy.

12. A ground condition assessment system comprising:

a parasitic power source configured to transmit a power signal;

an ensemble of microradios dispersed over the ground and configured to receive said power signal, each of said microradios including a rectifier, a capacitor to be parasitically powered, coupled to the rectifier, an oscillator coupled to the capacitor, a hysteretic switch coupled between the rectifier and the capacitor, a radiative structure coupled to both said rectifier and said oscillator to permit the charging of the capacitor in the microradio when a sufficient charge has been collected on the capacitor and then to discharge the capacitor to permit release of sufficient energy to power the microradio, whereby the microradios can be powered with relatively low levels of incident energy;

sensors within the microradios configured to emit sensor data;

a demodulator configured to demodulate and record the data emitted from the microradio sensors.

13. The system of claim 12, wherein the ensemble of microradios is dispersed over ground covered with crops and wherein said sensors are configured to sense crop health.

14. The system of claim 12, wherein said sensors are configured to sense explosive devices on the ground.

15. The system of claim 12, wherein said ensemble of microradios are configured to operate coherently to afford an n² power advantage.

16. The system of claim 15, further comprising a satellite configured to overfly the ground and receive sensor data emitted from the microradios.

17. The system of claim 12, wherein the parasitic power source comprises naturally-ocurring energy in the environment.

18. The system of claim 12, wherein the parasitic power source comprises a low-flying vehicle configured to project energy toward the ensemble of microradios.

19. The system of claim 12, wherein the microradios are at least partially coated with a conductive adhesive coating.

20. The system of claim 12, wherein the microradios are configured to respond to predetermined access codes, and further comprising a transmission source configured to transmit an access code to selected groups of the microradios.