Transducer network bus

• US 20020012401A1
• Filed: 05/17/2001
• Published: 01/31/2002
• Est. Priority Date: 05/23/2000
• Status: Abandoned Application

• Current Assignee: Endevco Corporation (Illinois Tool Works Inc.)
• Original Assignee: Endevco Corporation (Illinois Tool Works Inc.)
• Inventors: Eller, Eldon E., Gen-Kuong, Fernando, Karolys, Alexis G.
• Application Number:
  US09/859,798
• Publication Number:
  US 20020012401A1
• Time in Patent Office: Days
• US Class Current: 375/257
• CPC Class Codes: G08C 15/02 simultaneously, i.e. using frequency division
• CPC Class Codes: G08C 15/04 the signals being modulated on carrier frequencies
• CPC Class Codes: G08C 19/02 in which the signal transmitted is magnitude of current or voltage G08C19/36, G08C19/38 take precedence
• CPC Class Codes: H04L 12/403 with centralised control, e.g. polling
• CPC Class Codes: H04L 2012/4028 the transportation system being an aircraft
• 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 sensor communications system includes different sensor modules which are connected to a master module on a two-wire multidrop transducer bus to provide multiple communication channels. The sensor modules transmit signals to and receive signals from the master module.

Claims

1. A communication bus for coupling signals between a master module and N slave sensor modules comprising:

a two-wire bus coupled to the master module and the N slave sensor modules, the two-wire bus providing M digital communication channels simultaneously.

2. The communication bus of claim 1 wherein the M digital communication channels include a Transmit Master/Receive Slave (TxM/RxS) channel, a Transmit Slave/Receive Master (TxS/RxM) channel and a Synchronization Clock (Clk) channel.

3. The communication bus of claim 2 wherein the signals are modulated using PAM, FDMA, TDMA, or CDMA encoding.

4. The communication bus of claim 2 wherein the signals are transmitted as current using current drivers.

5. The communication bus of claim 2 further including a power signal distributed from the master module to the slave sensor modules.

6. A sensor communication system comprising:

a communication bus having at least two digital communication channels;

plural slave sensor modules coupled to the communication bus operable to transmit slave sensors signals and to receive master control signals in the at least two digital communication channels; and

a master module coupled to the communication bus operable to transmit the master control signals and to receive the slave sensor signals in the at least two digital communication channels.

7. The sensor communication system of claim 6 wherein the communication bus comprises a two-wire bus coupled to the master module and the plural slave sensor modules, the two-wire bus providing the at least two digital communication channels simultaneously.

8. The sensor communication system of claim 7 wherein the digital communication channels include a Transmit Master/Receive Slave (TxM/RxS) channel and a Transmit Slave/Receive Master (TxS/RxM) channel.

9. The sensor communication system of claim 8 wherein the master module is operable to transmit a Synchronization Clock (Clk) signal in a clock channel.

10. The sensor communication system of claim 8 wherein the signals are modulated using PAM, FDMA, TDMA, or CDMA encoding.

11. The sensor communication system of claim 8 wherein the signals are transmitted as current using current drivers.

12. The sensor communication system of claim 8 further including a power signal distributed from the master module to the slave sensor modules.

13. The sensor communication system of claim 6 wherein the slave sensor modules are operable to transmit slave signals in one of the at least two digital communication channels and the master module is operable to transmit master control signals in a different one of the at least two digital communication channels.

14. The sensor communication system of claim 6 wherein each slave sensor module is operable to transmit a first slave signal in a first one of the at least two digital communication channels and to transmit a second slave signal in a second one of the at least two digital communication channels.

15. The sensor communication system of claim 14 wherein the master module is operable to transmit a first master control signal in a third one of the at least two digital communication channels.

16. The sensor communication system of claim 15 wherein the master module is operable to transmit a second master control signal in a fourth one of the at least two digital communication channels.

17. The sensor communication system of claim 6 wherein the master module comprises:

at least one encoder/modulator for encoding and modulating a master control signal for transmitting in one of the at least two digital communication channels on the communication bus; and

at least one decoder/demodulator for decoding and demodulating a slave sensor signal received in a different one of the at least two digital communication channels on the communication bus.

18. The sensor communication system of claim 17 wherein the encoder/modulator and the decoder/demodulator use direct sequence spread spectrum modulation/demodulation.

19. The sensor communication system of claim 17 wherein the encoder/modulator and the decoder/demodulator use pulse amplitude modulation/demodulation.

20. The sensor communication system of claim 17 wherein the master module includes a power coupler for coupling a power signal to the communication bus.

21. The sensor communication system of claim 6 wherein the slave module comprises:

at least one encoder/modulator for encoding and modulating a slave signal for transmitting in one of the at least two digital communication channels on the communication bus; and

at least one decoder/demodulator for decoding and demodulating a master control signal received in a different one of the at least two digital communication channels on the communication bus.

22. The sensor communication system of claim 21 wherein the encoder/modulator and the decoder/demodulator use direct sequence spread spectrum modulation/demodulation.

23. The sensor communication system of claim 21 wherein the encoder/modulator and the decoder/demodulator use pulse amplitude modulation/demodulation.

24. The sensor communication system of claim 21 wherein the slave module includes a power de-coupler for de-coupling a power signal from the communication bus.

25. A method of communication comprising:

a) coupling plural slave sensor modules and a master module to a communication bus providing at least two digital communication channels;

b) transmitting slave sensors signals and receiving master control signals in the least two digital communication channels at the plural slave sensor modules;

c) transmitting the master control signals and receiving the slave sensor signals in the least two digital communication channels at the master module.

26. The method of claim 25 wherein transmitting includes modulating the signals using PAM, FDMA, TDMA, or CDMA encoding.

27. The method of claim 25 wherein step c) includes:

encoding and modulating a master control signal for transmitting in one of the at least two digital communication channels on the communication bus; and

decoding and demodulating a slave sensor signal received in a different one of the at least two digital communication channels on the communication bus.

28. The method of claim 25 wherein step b) includes:

encoding and modulating a slave signal for transmitting in one of the at least two digital communication channels on the communication bus; and

decoding and demodulating a master control signal received in a different one of the at least two digital communication channels on the communication bus.

29. A communication system comprising:

means for coupling plural slave sensor modules to a communication bus providing at least two digital communication channels;

means for transmitting slave sensors signals and receiving master control signals in the least two digital communication channels;

means for coupling a master module to the communication bus; and

means for transmitting the master control signals and receiving slave sensor signals in the least two digital communication channels.