Intelligent network sensor system

• US 10,158,401 B2
• Filed: 02/27/2015
• Issued: 12/18/2018
• Est. Priority Date: 02/27/2015
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Hull, Jonathan J., Gudan, Ken, Binnamangalam, Harsha
• Primary Examiner(s): Casillashernandez, Omar
• Application Number:
  US14/634,467
• Publication Number:
  US 20160254844A1
• Time in Patent Office: 1,390 Days
• Field of Search: 340 61, 340 101, 340 103, 455574, 455127, 4553431, 4553435
• CPC Class Codes: H04B 5/77 for interrogation
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 52/0296 switching to a backup power supply
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A network sensor system and method for using the same are disclosed herein. In one embodiment, the network sensor system comprises: a radio-frequency (RF) emitter; a first sensor tag including a transmitter, an energy harvesting unit operable to convert incident RF energy to direct current (DC) including RF energy from the RF emitter and RF energy from one or more ambient sources, a storage unit operable to store recovered DC power, one or more sensors for sensing and logging data, a controller coupled to the energy harvesting and storage units, the one or more sensors and the transmitter, to communicate data in the form of a Bluetooth Low Energy (BLE) advertising packet using energy previously harvested and stored by the energy harvesting and storage unit; and a first device to receive the BLE advertising packet.

Claims

1. A network sensor system comprising:

a radio-frequency (RF) emitter;

a first sensor tag including

a transmitter,

an energy harvesting unit operable to convert incident RF energy to direct current (DC) including RF energy from the RF emitter and RF energy from one or more ambient sources,

a storage unit operable to store recovered DC power,

one or more sensors for sensing and logging data,

a controller coupled to the energy harvesting and storage units, the one or more sensors and the transmitter, to communicate data in the form of a Bluetooth Low Energy (BLE) advertising packet using energy previously harvested and stored by the energy harvesting and storage unit; and

a first device to receive the BLE advertising packet,

the first device being operable to determine whether the first sensor tag is to perform a transmit operation or is not to perform a transmit operation, and to cause a message to be transmitted to the first sensor tag based on results of determining whether the first sensor tag is to perform the transmit operation, wherein the first device is operable to determine whether the first sensor tag is to perform the transmit operation based on charge rate of the first sensor tag, an amount of energy necessary for the first sensor tag to complete the transmit operation, and an amount of time necessary for the first sensor tag to complete the transmit operation,

wherein the first sensor tag is operable to determine a charge energy for each of a plurality of frequencies transmitted from the RF emitter executing a sweep algorithm and identifies one of the plurality of frequencies as one frequency that produced more charge energy than any other of frequencies of the plurality of frequencies, and

wherein the BLE advertising packet includes the identified one frequency.

2. The system defined in claim 1 wherein the RF emitter is operable to perform the sweep algorithm in which the RF emitter transmits RF energy at a plurality of frequencies to enable determination of which frequency among the plurality of frequencies provides a greatest power transfer efficiency (PTE) for the first sensor tag.

3. The system defined in claim 2 wherein the PTE for the first sensor tag is based on the charge energy at the one frequency and the received signal strength of the BLE advertising packet from the first sensor tag.

4. The system defined in claim 2 wherein the first device is operable to transmit a wakeup indication to the first sensor tag at a time associated with a start of the sweep algorithm to enable the first sensor tag to synchronize with the RF emitter when the RF emitter performs the sweep algorithm.

5. The system defined in claim 1 wherein the first sensor tag includes first, second and third modes of operation, wherein

in the first mode, in response to a first pulse, the first sensor tag transmits identification information,

in the second mode, in response to a second pulse, the first sensor tag receives a notification that the first sensor tag is to provide information to the first device without having to turn on its receiver for receiving the plurality of frequencies transmitted by the RF emitter, and

in the third mode, in response to a third pulse, the first sensor tag receives a notification that the first sensor tag is to provide information to the first device and turn on its receiver for receiving the plurality of frequencies transmitted by the RF emitter.

6. The system defined in claim 1 wherein the BLE advertising packet contains ID information.

7. The system defined in claim 1 wherein the BLE advertising packet contains one or more sensor readings from the one or more sensors.

8. The system defined in claim 1 wherein the first device comprises a smart phone or an internet gateway.

9. The system defined in claim 1 wherein the first device converts the BLE advertising packet to a message for transmission over the Internet.

10. A sensor tag for use in a sensor system, the sensor tag comprising:

a transmitter;

an energy harvesting unit operable to convert incident RF energy to direct current (DC) including RF energy from a RF emitter and RF energy from one or more ambient sources;

a storage unit operable to store recovered DC power;

one or more sensors for sensing and logging data;

a controller coupled to the energy harvesting and storage units, the one or more sensors and the transmitter, to communicate data from in the form of a Bluetooth Low Energy (BLE) advertising packet using energy previously harvested and stored by the energy harvesting and storage unit,

wherein the sensor tag determines the charge energy for each of a plurality of frequencies transmitted from the RF emitter executing a sweep algorithm and identifies one of the plurality of frequencies as one frequency that produced more charge energy than any other of frequencies of the plurality of frequencies, and

wherein the BLE advertising packet includes the identified one frequency, and

wherein a first device is operable to determine whether the sensor tag is to perform a transmit operation or is not to perform a transmit operation, and to cause a message to be transmitted to the sensor tag based on results of determining whether the sensor tag is to perform the transmit operation,

wherein the controller controls the sensor tag in first, second and third modes of operation, wherein

in the first mode, in response to a first pulse, a radio transmits identification information,

in the second mode, in response to a second pulse, the radio transmits information without having to turn on its receiver for receiving the plurality of frequencies transmitted by the RF emitter, and

in the third mode, in response to a third pulse, the radio transmits information and turns on its receiver for receiving the plurality of frequencies transmitted by the RF emitter.

11. The sensor tag defined in claim 10 wherein the sensor tag receives a wakeup indication to synchronize itself with the RF emitter when the RF emitter performs the sweep algorithm.

12. The sensor tag defined in claim 10 wherein the BLE advertising packet contains ID information.

13. The sensor tag defined in claim 10 wherein the BLE advertising packet contains one or more sensor readings from the one or more sensors.

14. A method for use in a sensor system having a tag, an RF emitter and a device, the method comprising:

performing, by the RF emitter, a sweep algorithm in which the RF emitter transmits RF energy at a plurality of frequencies;

determining, by the tag, charge energy for each of the plurality of frequencies;

identifying, by the tag, one of the plurality of frequencies as one frequency that produced more charge energy than any other of frequencies of the plurality of frequencies;

transmitting, by the tag, communication data in the form of a Bluetooth Low Energy (BLE) advertising packet including the identified one frequency;

determining which frequency among the plurality of frequencies provides a greatest power transfer efficiency (PTE) for the tag;

determining, by the device, whether the tag is to perform a transmit operation or is not to perform a transmit operation, including determining, by the device, whether the tag is to perform the transmit operation based on charge rate of the tag, an amount of energy necessary for the tag to complete the operation, and an amount of time necessary for the tag to complete the operation; and

sending an indication to the tag based on results of determining whether the tag is to perform the transmit operation.

15. The method defined in claim 14 wherein the PTE for the tag is based on the charge energy at the one frequency and the received signal strength of the BLE advertising packet from the tag.

16. The method defined in claim 14 further comprising transmitting, by the device, a wakeup indication to the tag at a time associated with a start of the sweep algorithm to enable the tag to synchronize with the RF emitter when the RF emitter performs the sweep algorithm.