Granted Patent B2

US 10,715,209 · App. 15/217,816 · Granted Jul 14, 2020

Inventor: Shahriar Rokhsaz (Austin, TX)

Assignee: RF Micron, Inc.

H04B1/713H03J3/20H04B5/0062H04B17/318H04W4/80H03J2200/10

Abstract

Claims (119)

1. A method comprises:

transmitting, by a computing device, a radio frequency (RF) signal to a passive wireless sensor, wherein the RF signal includes a carrier frequency signal and a modulated sense request signal, and wherein the RF signal is down converted and demodulated by the passive wireless sensor to recover a sense request signal of the modulated sense response signal;

in response to the modulated sense request signal, receiving, by the computing device, a response RF signal that includes the carrier frequency signal and a coded sense response signal from the passive wireless sensor, wherein the coded sense response signal is representative of a sensed environmental condition by the passive wireless sensor, wherein the sensed environmental condition affects impedance of a front-end of the passive wireless sensor to produce an affected impedance; and wherein the passive wireless sensor generates the coded sense response signal based on tuning the affected impedance to resonate with the carrier frequency signal; and

generating, by the computing device, an environmental condition value based on the coded sense response signal and an environmental conversion information.

2. The method of claim 1 further comprises:

prior to receiving the response RF signal, receiving, by the computing device, another response RF signal that includes the carrier frequency and a received power level indication signal that is representative of received signal strength of the RF signal;

determining, by the computing device, whether the received signal strength of the RF signal is at a desired level for enabling the wireless sensor to generate an accurate coded sense response signal;

when the received signal strength of the RF signal is not at the desired level:

adjusting, by the computing device, transmit power of the RF signal; and

transmitting, by the computing device, the RF signal at an adjusted transmit power level.

3. The method of claim 1 further comprises:

receiving, by the computing device, another response RF signal that includes the carrier frequency and a received power level indication signal that is representative of received signal strength of the RF signal;

determining, by the computing device, a coded value error factor based on the received signal strength of the RF signal and a desired received signal strength;

adjusting, by the computing device, a coded value of the coded sensed response signal based on the coded value error factor to produce an adjusted coded value; and

generating, by the computing device, the environmental condition value based on the adjusted coded value and the environmental conversion information.

4. The method of claim 1 further comprises:

generating, by the passive wireless sensor, a power supply voltage from the carrier frequency signal;

down converting, by the passive wireless sensor, the RF signal to recover the sense request signal;

tuning, by the passive wireless sensor, the impedance of the front-end of the passive wireless sensor to resonate with the carrier frequency, wherein the front-end includes a sensing element for sensing an environmental condition and wherein the sensing of the environmental condition by the sensing element alters the impedance of the front-end; and

generating, by the passive wireless sensor, the coded sense response signal as a representation of the tuning of the impedance of the front-end.

5. The method of claim 4 , wherein the generating the environmental condition value comprises:

determining a type of environmental condition being sensed by the passive wireless sensor;

selecting, as the environmental conversion information, one of a plurality of environmental conversion databases based on the type of environmental condition;

recovering a coded value from the coded sense response signal; and

utilizing the coded value as an operand to the one of the plurality of environmental conversion databases to generate the environmental condition value.

6. The method of claim 1 further comprises:

configuring, by the computing device, a software define transceiver for communicating with the passive wireless sensor.

7. The method of claim 1 further comprises:

initiating, by the computing device, a calibration process with the passive wireless sensor, wherein the passive wireless sensor is subjected to a known environmental condition;

receiving, by the computing device, a response calibration RF signal that includes the carrier frequency signal and a coded calibration signal from the passive wireless sensor, wherein the coded calibration signal is representative of the known environmental condition by the passive wireless sensor;

generating, by the computing device, a calibration reference environmental condition value based on the coded calibration signal and the environmental conversion information;

comparing, by the computing device, the calibration reference environmental condition value with the known environmental condition;

when the calibration reference environmental condition value compares unfavorably with the known environmental condition:

adjusting, by the computing device, the environmental conversion information based on a difference between the calibration reference environmental condition value and the known environmental condition; or

sending, by the computing device, a calibration offset to the passive wireless sensor, wherein the passive wireless sensor utilizes the calibration offset when generating the coded sense response signal such that the coded sense response signal is a more accurate representation of the sensed environmental condition.

8. The method of claim 1 further comprises:

transmitting, by the computing device, a second RF signal to a second passive wireless sensor, wherein the second RF signal includes the carrier frequency signal and a second modulated sense request signal, and wherein the second RF signal is down converted and demodulated by the second passive wireless sensor to recover a second sense request signal of the second modulated sense response signal;

in response to the second modulated sense request signal, receiving, by the computing device, a second response RF signal that includes the carrier frequency signal and a second coded sense response signal from the second passive wireless sensor, wherein the coded sense response signal is representative of a second sensed environmental condition by the second passive wireless sensor, wherein the second sensed environmental condition affects the impedance of a second front-end of the second passive wireless sensor to produce a second affected impedance; and wherein the second passive wireless sensor generates the second coded sense response signal based on by tuning the second affected impedance to resonate with the carrier frequency signal; and

generating, by the computing device, a second environmental condition value based on the second coded sense response signal and second environmental conversion information.

9. The method of claim 1 further comprises:

transmitting, by the computing device, the RF signal to the passive wireless sensor using a frequency hopping scheme, wherein the RF signal includes, for a first hop of the frequency hopping scheme, a first carrier frequency signal of a plurality of carrier frequency signals and the modulated sense request signal and includes, for a second hop of the frequency hopping scheme, a second carrier frequency signal of the plurality of carrier frequency signals and the modulated sense request signal;

in response to the modulated sense request signal:

receiving, by the computing device, a first response RF signal that includes the first carrier frequency signal and a first coded sense response signal from the passive wireless sensor, wherein the first coded sense response signal is a first representative of the sensed environmental condition by the passive wireless sensor;

receiving, by the computing device, a second response RF signal that includes the second carrier frequency signal and a second coded sense response signal from the passive wireless sensor, wherein the second coded sense response signal is a second representative of the sensed environmental condition by the passive wireless sensor; and

generating, by the computing device, the environmental condition value based on the first and second coded sense response signal, the environmental conversion information, the first carrier frequency signal, and the second carrier frequency signal.

10. The method of claim 1 , wherein the environmental condition value is a measure of one of:

temperature;

moisture;

pressure;

weight;

humidity;

gas percentages;

location proximity;

light; and

liquid properties.

11. The method of claim 1 further comprises:

initiating, by the computing device, a calibration process with the passive wireless sensor, wherein the passive wireless sensor is subjected to a first known environmental condition and to a second known condition;

receiving, by the computing device, a first response calibration RF signal that includes the carrier frequency signal and a first coded calibration signal from the passive wireless sensor, wherein the first coded calibration signal includes a first coded value corresponding to a measurement of the first known environmental condition by the passive wireless sensor;

receiving, by the computing device, a second response calibration RF signal that includes the carrier frequency signal and a second coded calibration signal from the passive wireless sensor, wherein the second coded calibration signal includes a second coded value corresponding to a measurement of the second known environmental condition by the passive wireless sensor;

storing, by the computing device, the first coded value as a first calibrated coded value for the first known condition; and

storing, by the computing device, the second coded value as a second calibrated coded value for the second known condition.

12. A computing device comprises:

a transceiver;

memory;

a processing module operably coupled to the transceiver and the memory, wherein the processing module is operable to:

transmit, via the transceiver, a radio frequency (RF) signal to a passive wireless sensor, wherein the RF signal includes a carrier frequency signal and a modulated sense request signal, and wherein the RF signal is down converted and demodulated by the passive wireless sensor to recover a sense request signal of the modulated sense response signal; in response to the modulated sense request signal, receive, via the transceiver, a response RF signal that includes the carrier frequency signal and a coded sense response signal from the passive wireless sensor, wherein the coded sense response signal is representative of a sensed environmental condition by the passive wireless sensor, wherein the sensed environmental condition affects impedance of a front-end of the passive wireless sensor to produce an affected impedance; and wherein the passive wireless sensor generates the coded sense response signal based on tuning the affected impedance to resonate with the carrier frequency signal; and

generate an environmental condition value based on the coded sense response signal and an environmental conversion information.

13. The computing device of claim 12 , wherein the processing module is further operable to:

prior to receiving the response RF signal, receive, via the transceiver, another response RF signal that includes the carrier frequency and a received power level indication signal that is representative of received signal strength of the RF signal;

determine whether the received signal strength of the RF signal is at a desired level for enabling the wireless sensor to generate an accurate coded sense response signal;

when the received signal strength of the RF signal is not at the desired level:

adjust transmit power of the RF signal; and

transmit, via the transceiver, the RF signal at an adjusted transmit power level.

14. The computing device of claim 12 , wherein the processing module is further operable to:

receive, via the transceiver, another response RF signal that includes the carrier frequency and a received power level indication signal that is representative of received signal strength of the RF signal;

determine a coded value error factor based on the received signal strength of the RF signal and a desired received signal strength;

adjust a coded value of the coded sensed response signal based on the coded value error factor to produce an adjusted coded value; and

generate the environmental condition value based on the adjusted coded value and the environmental conversion information.

15. The computing device of claim 12 , wherein the processing module is further operable to generate the environmental condition value by:

determining a type of environmental condition being sensed by the passive wireless sensor;

selecting, as the environmental conversion information, one of a plurality of environmental conversion databases based on the type of environmental condition;

recovering a coded value from the coded sense response signal; and

utilizing the coded value as an operand to the one of the plurality of environmental conversion databases to generate the environmental condition value.

16. The computing device of claim 12 further comprises:

the transceiver including a software define transceiver; and

the processing module is further operable to further operable to configure the software define transceiver for communicating with the passive wireless sensor.

17. The computing device of claim 12 , wherein the processing module is further operable to:

initiate a calibration process with the passive wireless sensor, wherein the passive wireless sensor is subjected to a known environmental condition;

receive, via the transceiver, a response calibration RF signal that includes the carrier frequency signal and a coded calibration signal from the passive wireless sensor, wherein the coded calibration signal is representative of the known environmental condition by the passive wireless sensor;

generate a calibration reference environmental condition value based on the coded calibration signal and the environmental conversion information;

compare the calibration reference environmental condition value with the known environmental condition;

when the calibration reference environmental condition value compares unfavorably with the known environmental condition:

adjust the environmental conversion information based on a difference between the calibration reference environmental condition value and the known environmental condition; or

send, via the transceiver, a calibration offset to the passive wireless sensor, wherein the passive wireless sensor utilizes the calibration offset when generating the coded sense response signal such that the coded sense response signal is a more accurate representation of the sensed environmental condition.

18. The computing device of claim 12 , wherein the processing module is further operable to:

transmit, via the transceiver, a second RF signal to a second passive wireless sensor, wherein the second RF signal includes the carrier frequency signal and a second modulated sense request signal, and wherein the second RF signal is down converted and demodulated by the second passive wireless sensor to recover a second sense request signal of the second modulated sense response signal;

in response to the second modulated sense request signal, receive, via the transceiver, a second response RF signal that includes the carrier frequency signal and a second coded sense response signal from the second passive wireless sensor, wherein the coded sense response signal is representative of a second sensed environmental condition by the second passive wireless sensor, wherein the second sensed environmental condition affects the impedance of a second front-end of the second passive wireless sensor to produce a second affected impedance; and wherein the second passive wireless sensor generates the second coded sense response signal based on by tuning the second affected impedance to resonate with the carrier frequency signal; and

generate a second environmental condition value based on the second coded sense response signal and second environmental conversion information.

19. The computing device of claim 12 , wherein the processing module is further operable to:

transmit, via the transmitter, the RF signal to the passive wireless sensor using a frequency hopping scheme, wherein the RF signal includes, for a first hop of the frequency hopping scheme, a first carrier frequency signal of a plurality of carrier frequency signals and the modulated sense request signal and includes, for a second hop of the frequency hopping scheme, a second carrier frequency signal of the plurality of carrier frequency signals and the modulated sense request signal;

in response to the modulated sense request signal:

receive, via the transceiver, a first response RF signal that includes the first carrier frequency signal and a first coded sense response signal from the passive wireless sensor, wherein the first coded sense response signal is a first representative of the sensed environmental condition by the passive wireless sensor;

receive, via the transceiver, a second response RF signal that includes the second carrier frequency signal and a second coded sense response signal from the passive wireless sensor, wherein the second coded sense response signal is a second representative of the sensed environmental condition by the passive wireless sensor; and

generate the environmental condition value based on the first and second coded sense response signal, the environmental conversion information, the first carrier frequency signal, and the second carrier frequency signal.

20. The computing device of claim 12 , wherein the environmental condition value is a measure of one of:

temperature;

moisture;

pressure;

humidity;

gas percentages;

location proximity;

light; and

liquid properties.

21. The computing device of claim 12 , wherein the processing module is further operable to:

initiate a calibration process with the passive wireless sensor, wherein the passive wireless sensor is subjected to a first known environmental condition and to a second known condition;

receive, via the transceiver, a first response calibration RF signal that includes the carrier frequency signal and a first coded calibration signal from the passive wireless sensor, wherein the first coded calibration signal includes a first coded value corresponding to a measurement of the first known environmental condition by the passive wireless sensor;

receive, via the transceiver, a second response calibration RF signal that includes the carrier frequency signal and a second coded calibration signal from the passive wireless sensor, wherein the second coded calibration signal includes a second coded value corresponding to a measurement of the second known environmental condition by the passive wireless sensor;

store the first coded value as a first calibrated coded value for the first known condition; and

store the second coded value as a second calibrated coded value for the second known condition.

Assignments (7)

Continuity (23)