SENSOR NETWORK USING PULSE WIDTH MODULATED SIGNALS

• US 20140365702A1
• Filed: 06/05/2013
• Published: 12/11/2014
• Est. Priority Date: 06/05/2013
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Ray, Gary A., Petre, Peter
• Granted Patent: US 9,582,452 B2
• Time in Patent Office: Days
• US Class Current: 710/305
• CPC Class Codes: G06F 13/4068 Electrical coupling
• CPC Class Codes: H04L 12/12 Arrangements for remote connection or disconnection of substations or of equipment thereof

Abstract

A device includes a bus interface to couple to a shared bus of a sensor network. The device also includes a sensor interface to couple to a sensor of the sensor network. The device further includes a gated pulse width modulation circuit coupled to the bus interface and to the sensor interface. The gated pulse width modulation circuit is configured to transmit, during a time slot determined based on a timing signal received via the shared bus, an analog pulse width modulated representation of a signal received from the sensor.

Claims

1. A device comprising:

a bus interface to couple to a shared bus of a sensor network;

a sensor interface to couple to a sensor of the sensor network; and

a gated pulse width modulation circuit coupled to the bus interface and to the sensor interface, the gated pulse width modulation circuit configured to transmit, during a time slot determined based on a timing signal received via the shared bus, an analog pulse width modulated representation of a signal received from the sensor.

2. The device of claim 1, wherein the gated pulse width modulation circuit comprises an asynchronous sigma-delta modulator circuit.

3. The device of claim 1, wherein the time slot corresponds to a media access time during each frame of a plurality of frames that is allocated to the device for transmission on the bus.

4. The device of claim 3, wherein the gated pulse width modulation circuit is configured to transmit the analog pulse width modulated representation of the signal received from the sensor during a first frame of the plurality of frames and transmit at least a portion of a node identifier of the device during a second frame of the plurality of frames.

5. The device of claim 1, further comprising a gate controller coupled to the gated pulse width modulation circuit, wherein the gate controller is configured to initiate activation of a switch of the gated pulse width modulation circuit when the time slot begins.

6. The device of claim 1, further comprising a clock to generate a clock signal that is offset from the timing signal, wherein the gated pulse width modulated circuit is enabled to transmit the analog pulse width modulated representation of the signal based on the clock signal.

7. The device of claim 1, further comprising a storage device configured to store time slot information, wherein the time slot information includes a transmit time slot identifier, a receive time slot identifier, a time slot width, or a combination thereof.

8. The device of claim 1, further comprising a time slot assignment device to:

monitor the bus for a time period;

detect, during the time period, a particular time slot during which no transmission by another device is detected; and

select the particular time slot as the time slot.

9. The device of claim 1, further comprising a receiver to receive second analog pulse width modulation data via the bus during a second time slot.

10. The device of claim 9, wherein the receiver comprises a gated leaky integrator low pass filter.

11. A sensor network comprising:

multiple sensors;

a bus; and

multiple sensor interface devices, each sensor interface device of the multiple sensor interface devices coupling a corresponding sensor of the multiple sensors to the bus, wherein a first sensor interface device of the multiple sensor interface devices includes;

a bus interface coupled to the bus;

a sensor interface coupled to a first corresponding sensor of the multiple sensors; and

a gated pulse width modulation circuit coupled to the bus interface and to the sensor interface, the gated pulse width modulation circuit configured to transmit, during a time slot determined based on a timing signal received via the bus, an analog pulse width modulated representation of a signal received from the first corresponding sensor.

12. The sensor network of claim 11, integrated in a structure, wherein the structure includes an aircraft, a spacecraft, a land craft, a watercraft, a mobile platform, an infrastructure platform, or a building.

13. The sensor network of claim 11, further comprising a receiver coupled to the bus to receive a pulse width modulated signal representing data from the first corresponding sensor.

14. The sensor network of claim 13, wherein the pulse width modulated signal is received during a particular time slot allocated to the first corresponding sensor, and wherein the receiver converts the pulse width modulated signal into a digital value.

15. The sensor network of claim 11, wherein a second sensor interface device of the multiple sensor interface devices includes a receiver to receive, via the bus, a pulse width modulated signal from the first sensor interface and to send data corresponding to the pulse width modulated signal to a second corresponding sensor of the multiple sensors, the second corresponding sensor coupled to the second sensor interface device, wherein the second corresponding sensor determines a signal based in part on the data corresponding to the pulse width modulated signal.

16. A method comprising:

receiving data from a sensor;

receiving a timing signal via a bus; and

transmitting an analog pulse width modulated representation of the data via the bus during a time slot determined based on the timing signal.

17. The method of claim 16, further comprising activating a switch based on identification of a beginning of the time slot to enable a transmission of the analog pulse width modulated representation of the data.

18. The method of claim 16, further comprising generating the analog pulse width modulated representation of the data during the time slot.

19. The method of claim 16, further comprising combining a carrier signal with the analog pulse width modulated representation of the data prior to transmitting the analog pulse width modulated representation of the data via the bus.

20. The method of claim 16, further comprising:

receiving second analog pulse width modulated data via the bus during a second time slot; and

sending a representation of the second analog pulse width modulated data to the sensor.