METHOD AND DEVICE FOR ESTIMATION OF THE TRANSMISSION CHARACTERISTICS OF A RADIO FREQUENCY SYSTEM

• US 20120225619A1
• Filed: 05/15/2012
• Published: 09/06/2012
• Est. Priority Date: 05/11/2007
• Status: Active Grant

• Current Assignee: Sky ID Incorporated
• Original Assignee: Sky ID Incorporated
• Inventors: CHARLAND, SHAWN
• Granted Patent: US 8,466,826 B2
• Time in Patent Office: Days
• US Class Current: 455/1
• CPC Class Codes: F41H 13/0075 the high-energy beam being a radiofrequency beam
• CPC Class Codes: H04B 17/327 Received signal code power [RSCP]
• CPC Class Codes: H04B 17/3913 Predictive models, e.g. based on neural network models
• CPC Class Codes: H04K 2203/24 for communication related to weapons
• CPC Class Codes: H04K 3/42 characterized by the control of the jamming frequency or wavelength
• CPC Class Codes: H04K 3/43 characterized by the control of the jamming power, signal-to-noise ratio or geographic coverage area
• CPC Class Codes: H04K 3/92 related to allowing or preventing remote control
• CPC Class Codes: H04K 3/94 related to allowing or preventing testing or assessing

Abstract

A device and method for estimation of the transmission characteristics of a Radio Frequency system are provided. The device and method calculate a predicted receive power at a given location using a propagation and scenario model. Then a measured receive power at the given location is used to determine a correction value equal to the difference between the calculated and measured receive powers. The correction value and the propagation model are then used with a heuristic method to refine estimates of propagation and scenario parameters. The refined parameter set is used to produce a refined prediction of receive power, which is used to create a refined correction factor. The refined correction factor is used to determine predicted receive powers at a plurality of locations.

Claims

1. A method comprising the steps of:

calculating for a first location a predicted received power level of an RF signal generated by a RF system transmitter;

determining a correction value based on the predicted received power level and an actual received power level of the RF signal at the first location; and

calculating for a second location a predicted received power level of the RF signal using the correction value.

2. The method of claim 1, further comprising:

calculating for the first location a plurality of predicted received power levels of the RF signal generated by the RF system transmitter, inclusive of calculating the first predicted received power level for the first location, wherein each one of the plurality of predicted received power levels corresponds to a respective frequency component of the RF signal;

measuring at the first location a plurality of actual received power levels of the RF signal generated by the RF system transmitter, inclusive of measuring the first actual received power level at the first location, wherein each one of the plurality of actual received power levels corresponds to one of the plurality of predicted received power levels;

determining a plurality of correction values based on the plurality of predicted received power levels and the plurality of measured received power levels, inclusive of determining the first correction value based on the first predicted received power level and the first measured received power level; and

calculating a plurality of predicted received power levels for the second location using the plurality of correction values, inclusive of calculating the first predicted received power level for the second location using the first correction value.

3. The method of claim 1, wherein the RF signal generated by the RF system transmitter comprises an electronic countermeasures (ECM) signal.

4. The method of claim 3, further comprising:

predicting probabilistic ability of the RF signal generated by the RF system transmitter to prevent triggering of a potential threat device at the second location based on the predicted received power level of the RF signal at the second location and potential threat device characteristics.

5. The method of claim 4, wherein the potential threat device characteristics comprise a predicted response of the potential threat device to the predicted received power level of the RF signal at the second location.

6. The method of claim 5 wherein the predicted response of the potential threat device to the predicted received power level of the RF signal comprises a predicted response of the potential threat device to a given jamming-to-signal ratio.

7. The method of claim 1, wherein determining the correction value comprises calculating the correction value according to:

Δ

P1=ECM<sub>meas—

at—

first—

location</sub>−

ECM<sub>unref—

at—

first—

location</sub>

where Δ

P1 is the correction value, ECM<sub>meas—

at—

first—

location</sub> is the actual received power level of the RF signal at the first location, and ECM<sub>unref—

at—

first—

location</sub> is the predicted received power level of the RF signal at the first location, wherein

calculating the predicted received RF signal at the second location comprises;

calculating an unrefined predicted received power level of the RF signal at the second location; and

calculating the predicted received power level of the RF signal at the second location according to;

ECM<sub>ref—

at—

second—

location</sub>=ECM<sub>unref—

at—

second—

location</sub>+Δ

P1

where ECM<sub>ref—

at—

second—

location</sub> is the predicted received power level of the RF signal at the second location, and ECM<sub>unref—

at—

second—

location</sub> is the unrefined predicted received power level of the RF signal at the second location.

8. The method of claim 4 further comprising:

generating a mismatch cost function based on a comparison of the predicted received power level of the RF signal at the first location and the actual measured received power level of the RF signal at the first location; and

indicating a fault/anomaly if the mismatch cost function exceeds a threshold value.

9. The method of claim 3 further comprising:

calculating a respective predicted received power level of the RF signal generated by the RF system transmitter for each location of a plurality of locations in an area around the device using the correction value; and

for each location predicting probabilistic ability of the RF signal generated by the RF system transmitter to prevent triggering of the potential threat device at the location based on the respective predicted received power level of the RF signal at the location and the potential threat device characteristics.

10. The method of claim 9, wherein the potential threat device characteristics comprise a predicted response of the potential threat device to the respective predicted received power level of the RF signal for each location of the plurality of locations in the area.

11. The method of claim 10 further comprising calculating a protection range of the RF system transmitter by determining a boundary at which the probabilistic ability of the RF signal generated by the RF system transmitter to prevent triggering of the potential threat device is at a safety threshold.

12. The method of claim 11 further comprising displaying the protective range of the RF system transmitter.

13. The method of claim 11, wherein calculating each respective predicted received power level of the RF signal comprises:

calculating a predicted received power level of the RF signal for each location for each one of a population of N scenario parameter sets to generate N predicted received power levels for each location,

wherein for each location the probabilistic ability of the RF signal generated by the RF system transmitter to prevent triggering of the potential threat device at the location is derived from the probabilistic effect of the N predicted received power levels of the RF signal for the location.

14. The method of claim 7 wherein generating the mismatch cost function comprises determining best-case and worst-case predicted received power levels of the RF signal at the first location,

wherein the worst-case predicted received power level of the RF signal at the first location is derived from N predicted received power levels of the RF signal at the first location calculated using N scenario parameter sets, and

wherein the best-case predicted received power level of the RF signal at the first location is derived from the N predicted received power levels of the RF signal at the first location.

15. The method of claim 13, further comprising, for each location:

determining an average predicted received power level of the RF signal from the N predicted received power levels of the RF signal; and

determining standard deviation of the N predicted received power levels of the RF signal.

16. The method of claim 13, further comprising:

predicting a worst-case protection range of the RF system transmitter;

predicting a predicted protection range of the RF system transmitter; and

displaying the worst-case and predicted protection ranges of the RF system transmitter.

17. The method of claim 1 wherein calculating a predicted received power level of the RF signal comprises calculating a predicted received power level of the RF signal using a propagation and scenario model.

18. The method of claim 17 further comprising adapting parameters of the model to substantially fit the predicted received power level of the RF signal at the first location to the measured received power level of the RF signal at the first location.

19. A computer readable medium having recorded thereon statements and instructions for execution by a computer to carry out a method comprising the steps of:

calculating a predicted power level of a radio frequency (RF) signal at a first location;

determining a correction value based on the predicted power level of the RF signal at the first location and an actual measured received power level of the RF signal measured at the first location; and

calculating a predicted power level of the RF signal at a second location using the correction value.

20. The computer readable medium of claim 19, wherein the RF signal comprises an electronic countermeasures (ECM) signal, and the method further comprises:

predicting probabilistic ability of the RF signal to prevent triggering of a potential threat device at the second location based on the predicted power level of the RF signal at the second location and potential threat device characteristics.