Multi-transmitter telemetry system

• US 20080224845A1
• Filed: 03/13/2007
• Published: 09/18/2008
• Est. Priority Date: 03/13/2007
• Status: Abandoned Application

• Current Assignee: United Technologies Corporation (Rtx Corporation)
• Original Assignee: United Technologies Corporation (Rtx Corporation)
• Inventors: Bires, Robert J.
• Application Number:
  US11/717,479
• Publication Number:
  US 20080224845A1
• Time in Patent Office: Days
• US Class Current: 340/501
• CPC Class Codes: G01K 1/024 for remote indication
• CPC Class Codes: G01K 1/026 arrangements for monitoring a plurality of temperatures, e.g. by multiplexing
• CPC Class Codes: G01L 1/2256 involving digital counting
• CPC Class Codes: H04Q 9/00 Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom

Abstract

A multi-transmitter telemetry system remotely controls and modifies the operating parameters associated with a plurality of addressable transmitter modules connected to collect data from a plurality of sensors. Control instructions remotely provided to each transmitter module include addressing data identifying the transmitter module to implement the control instructions. Although each transmitter module decodes the control instructions, only the addressed transmitter module implements the provided instructions. In this way, individual transmitters employed in a multi-transmitter telemetry system may be individually addressed and remotely controlled.

Claims

1. A multi-transmitter telemetry system for collecting data from a plurality of sensors located on a rotating member, the multi-transmitter telemetry system comprising:

a control room modulator that encodes transmitter specific command instructions that include addressing instructions and control instructions onto an AC power carrier signal;

a plurality of uniquely addressable transmitter modules located on the rotating member, each transmitter module having transmitter circuitry for receiving data from one of the plurality of sensors and transmitting the received data by modulating the received data onto a unique radio carrier signal;

wherein each transmitter module includes decoding circuitry for decoding the command instructions encoded within the AC power carrier signal and comparing the addressing instructions to a stored address that uniquely identifies each transmitter module to determine whether to modify operating parameters associated with the transmitter circuitry based on the decoded control instructions; and

control room circuitry that receives and decodes data transmitted by each of the plurality of uniquely addressable transmitter modules on the plurality of unique radio carrier signal frequencies.

2. The multi-transmitter telemetry system of claim 1, wherein the plurality of sensors providing data to each transmitter module includes both high-bandwidth sensors and low-bandwidth sensors.

3. The multi-transmitter telemetry system of claim 1, wherein the transmitter circuitry includes:

a first strain gauge circuit connected to receive control instructions from the transmitter module and to provide strain data measured by a first strain gauge sensor to the transmitter module on a first channel;

a second strain gauge circuit connected to receive control instructions from the transmitter module and to provide strain data measured by a second strain gauge sensor to the transmitter module on a second channel; and

wherein the control instructions provided to the first strain gauge circuit and the second strain gauge circuit selectively determine whether the strain data is provided to the transmitter module on the first channel only, the second channel only, or both the first and second channels simultaneously.

4. The multi-transmitter telemetry system of claim 3, wherein a strain gauge circuit includes:

a constant current source that provides power to a strain gauge, wherein the control instructions include an on/off instruction that determines whether excitation is provided by the constant current source to the strain gauge;

an amplifier that provides amplification to a signal provided by the strain gauge, wherein the control instructions include a gain selection instruction that determines the gain provided by the amplifier;

an anti-aliasing filter that provides anti-aliasing filtering to the amplified signal, wherein the control instructions include a filter frequency instruction that determines the filter frequency of the anti-aliasing filter; and

an analog-to-digital converter that converts an analog signal provided by the anti-aliasing filter to a digital signal that is provided to the transmitter module, wherein the control instructions include a sampling rate control instruction that determines the sampling rate of the analog-to-digital converter.

5. The multi-transmitter telemetry system of claim 4, further including:

a delta-R calibration circuit connected to the strain gauge sensor, wherein the control instructions include a delta-R calibration instruction that selectively inserts a known change in resistance in series with the strain gauge sensor.

6. The multi-transmitter telemetry system of claim 1, wherein each of the plurality of transmitter modules includes:

a transmitter carrier generator for generating the radio carrier signal; and

a transmitter digital modulator that modulates data provided by the plurality of sensors onto the radio carrier signal, wherein a frequency of the radio carrier signal employed by each of the plurality of transmitter modules may be selectively controlled by the transmitter module based on the decoded control instructions.

7. The multi-transmitter telemetry system of claim 1, wherein the radio carrier signal generated by each transmitter module may be selectively turned ‘

on’

or ‘

off’

based on the decoded control instructions.

8. The multi-transmitter telemetry system of claim 6, wherein each of the plurality of transmitter modules further includes:

a phase-locked loop (PLL) circuit that selectively controls the frequency of the radio carrier signal generated by the transmitter carrier generator based on decoded control instructions, a reference frequency provided as part of the AC power carrier signal, and feedback provided by the transmitter carrier generator.

9. The multi-transmitter telemetry system of claim 6, wherein the transmitter digital modulator included with each of the transmitter modules employs an offset quadrature phase shift keying digital modulation.

10. The multi-transmitter telemetry system of claim 1, further including:

a magnet located on the rotating member;

a magnetic pick-up sensor located on a stationary member, wherein the magnetic pick-up sensor provides a pulse responsive to the magnet; and

a receiver that determines the speed of the rotating member based on the pulses provided by the magnetic pick-up sensor.

11. A transmitter module for use in a digital telemetry system, the transmitter module comprising:

a storage medium for storing an unique address associated with the transmitter module;

a power supply that rectifies alternating current (AC) power received from an external source and generates direct current (DC) power output;

a tone decoder for detecting the presence of command instructions digitally modulated onto the AC power;

a command signal decoder that decodes command instructions embedded within the AC power and compares addressing information provided as part of the decoded command instructions to the unique address provided by the storage medium, wherein if the decoded command instruction corresponds with the unique address provided by the storage medium then command signal decoder generates control instructions based on the decoded command instructions;

sensing circuitry for receiving data from a sensor and configurable based on control instructions provided by the command signal decoder;

a PCM encoder that generates a data bitstream in response to data received from the sensing circuitry;

a carrier generator for generating a radio frequency carrier signal; and

a digital modulator that modulates the data bitstream received from the PCM encoder onto the radio frequency carrier signal at a frequency that is configurable by the control instructions.

12. The transmitter module of claim 11, wherein the sensing circuitry includes:

a first analog strain gauge sensing circuitry connected to provide a first channel of strain control data to the PCM encoder from a first strain gauge sensor;

a second analog strain gauge sensing circuitry connected to provide a second channel of strain control data to the PCM encoder from a second strain gauge sensor; and

wherein the command signal decoder communicates the control instructions to the first and second analog strain gauge sensing circuitry to selectively and individually control operating parameters associated with both the first and second analog strain gauge sensing circuitry.

13. The transmitter module of claim 11, wherein the operating parameters associated with the first and second analog strain gauge sensing circuitry include bandwidth allocation between the first strain gauge sensor and the second strain gauge sensor.

14. The transmitter module of claim 11, wherein the strain gauge sensing circuitry includes:

a switch positioned between a power supply and the strain gauge sensor that in response to a on/off control instruction received from the command signal decoder provides excitation to the strain gauge sensor.

15. The transmitter module of claim 11, wherein the strain gauge sensing circuitry includes:

a delta-R calibration circuit that in response to a delta-R control instruction received from the command signal decoder alternately provides a known change in resistance in series with the strain gauge.

16. The transmitter module of claim 11, wherein the strain gauge sensing circuitry includes:

an amplifier circuit connected to receive an analog signal generated by the strain gauge sensor, wherein in response to a gain control instruction received from the command signal decoder the amplifier circuit provides a selected amount of amplification to the analog signal.

17. The transmitter module of claim 11, wherein the strain gauge sensing circuitry include:

an anti-aliasing filter that receives an analog signal generated by the strain gauge sensor, wherein in response to a filter frequency control instruction received from the command signal decoder the anti-aliasing filter selectively filters the analog signal.

18. The transmitter module of claim 11, wherein both the first and second strain gauge sensing circuitry include:

an analog-to-digital converter that converts an analog signal generated by the strain gauge sensor to a digital signal that is provided to the PCM encoder, wherein in response to a sampling rate control instruction received from the command signal decoder the analog-to-digital converter operates at a selected sampling rate.

19. The transmitter module of claim 11, wherein the sensing circuitry includes:

a multiplexer that is connected to receive input from a plurality of low-bandwidth direct current (DC) sources and provide input from one of the plurality of low-bandwidth DC sources to the PCM encoder in response to input selection instructions received from the command signal decoder.

20. The transmitter module of claim 19, wherein the plurality of inputs received by the multiplexer include:

temperature data provided by a temperature sensor located within the transmitter module.

21. The transmitter module of claim 19, wherein the plurality of inputs received by the multiplexer include:

power transmission data provided by a sensor connected to monitor power received by the transmitter module from the external source.

22. The transmitter module of claim 11, further including:

a phase locked loop (PLL) circuit that selectively controls the frequency of the radio frequency carrier signal that is generated by the carrier generator based on a reference frequency derived from the external source and a frequency control instruction provided by the control instructions.

23. A method for operating a transmitter module in a multi-transmitter telemetry system, the method comprising:

receiving an AC power signal from a source external to the transmitter module;

decoding a command signal embedded within the AC power signal, wherein the command signal includes addressing data and control instructions;

comparing the addressing data provided by the command signal to a stored address that uniquely identifies the transmitter module to determine whether the command instruction is addressed to the transmitter module;

modifying operating parameters associated with the transmitter circuitry based on the control instructions and the outcome of the comparison between the addressing data and the stored address;

receiving sensor data provided by a sensor;

embedding the received sensor data onto a radio frequency carrier signal; and

transmitting the radio frequency carrier signal with embedded sensor data to a receiver external to the transmitter module;

24. The method of claim 23, wherein modifying operating parameters associated with the transmitter circuitry includes:

modifying the frequency of the radio frequency carrier signal based on the decoded control instructions.

25. The method of claim 23, wherein modifying operating parameters associated with the transmitter circuitry includes:

selectively generating the radio frequency carrier signal based on the decoded control instructions.

26. The method of claim 23, wherein modifying operating parameters associated with the transmitter circuitry includes:

modifying sensor circuitry in response to the decoded control instructions to select which of a plurality of sensors will provide sensor data to the sensor circuitry.

27. The method of claim 23, wherein modifying operating parameters associated with the transmitter circuitry includes:

modifying sensor circuitry in response to the decoded control instructions to provide a select amount of gain to the sensor data provided by the sensor.

28. The method of claim 23, wherein modifying operating parameters associated with the transmitter circuitry includes:

modifying sensor circuitry in response to the decoded control instructions to allocate bandwidth between two or more sensors.

29. The method of claim 23, wherein modifying operating parameters associated with the transmitter circuitry includes:

modifying sensor circuitry in response to the decoded control instructions to selectively turn off excitation to the sensor.

30. The method of claim 23, wherein modifying operating parameters associated with the transmitter circuitry includes:

modifying sensor circuitry in response to the decoded control instructions to selectively provide delta-R calibration to sensor data provided by the sensor.

31. The method of claim 23, wherein modifying operating parameters associated with the transmitter circuitry includes:

modifying sensor circuitry in response to the decoded control instructions to select a filter frequency to be applied to the sensor data provided by the sensor.

32. The method of claim 23, wherein modifying operating parameters associated with the transmitter circuitry includes:

modifying sensor circuitry in response to the decoded control instructions to select a sample to be used by an analog-to-digital converter for converting analog sensor data to a digital sensor data.

33. The method of claim 23, wherein receiving sensor data provided by a sensor includes:

receiving high-bandwidth data from a plurality of high-bandwidth sensors; and

receiving direct current (DC) coupled low-bandwidth data from a plurality of low-bandwidth sensors.

34. The method of claim 23, wherein embedding the received sensor data onto a radio frequency carrier signal includes:

modulating the radio frequency carrier signal with the received sensor data using offset quadrature phase shift keying digital modulation.

35. The method of claim 23, further including:

embedding the command instructions into the AC power signal at a location external to the transmitter module; and

transmitting the AC power signal to each of a plurality of transmitter modules employed in the multi-transmitter telemetry system.

36. The method of claim 23, further including:

receiving at a location external to the transmitter module a plurality of radio frequency carrier signals, wherein each of the radio frequency carrier signals is provided at a unique frequency by one of a plurality of transmitter modules employed in the multi-transmitter telemetry system.