Digital Communication System for Loudspeakers

• US 20150189430A1
• Filed: 03/12/2015
• Published: 07/02/2015
• Est. Priority Date: 10/22/2009
• Status: Active Grant

• Current Assignee: Dolby Laboratories Licensing Corporation (Dolby Laboratories Incorporated)
• Original Assignee: Dolby Laboratories Licensing Corporation (Dolby Laboratories Incorporated)
• Inventors: Butler, Joel
• Granted Patent: US 9,615,169 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04R 2420/07 Applications of wireless loudspeakers or wireless microphones
• CPC Class Codes: H04R 3/00 Circuits for transducers , loudspeakers or microphones
• CPC Class Codes: H04R 3/12 for distributing signals to two or more loudspeakers specially adapted for hearing aids H04R25/407

Abstract

A communication system for communicating with at least one loudspeaker is described where the loudspeaker is connected to audio equipment over standard two-wire speaker wire operable to carry an audio signal. The communication system includes a master node in electrical communication with a signal path carrying the audio signal between the audio equipment and the loudspeaker, the master node also including an interface with the audio equipment, a data encoder operable to encode data signals, a data transceiver operable to place the data signals onto the audio signal at frequencies above audio frequencies. The communication system also includes at least one slave node in electrical communication with the audio signal and each loudspeaker, the slave node including a data transceiver operable to receive data signals from the master node, a data decoder, and an interface able to communicate with the loudspeaker.

Claims

1. A communication system for communicating with a loudspeaker where the loudspeaker is connected to audio equipment over a standard two-wire speaker wire operable to carry an analog audio signal, wherein the analog audio signal is a high-voltage, high-current analog audio signal, the communication system comprising:

a master node in electrical communication with an analog signal path carrying the analog audio signal between the audio equipment and the loudspeaker, wherein the master node is alternating current (AC) coupled to the standard two-wire speaker wire, wherein the master node includes a data encoder operable to encode data signals, and a data transceiver operable to place the data signals onto the analog audio signal at frequencies above audio frequencies; and

a slave node in electrical communication with the master node and the loudspeaker, wherein the slave node is AC coupled to the standard two-wire speaker wire, wherein the slave node includes a data transceiver operable to receive the data signals from the master node, a data decoder and an interface able to communicate with electronics in the loudspeaker, wherein the analog signal path is able to simultaneously transmit both the analog audio signal and the data signals,

wherein the slave node is operable to receive a control signal in the data signals from the master node, and responsive to the control signal, to control a parameter of the electronics in the loudspeaker.

2. The communication system of claim 1 wherein the loudspeaker comprises a first loudspeaker, wherein the slave node comprises a first slave node, the communication system further comprising:

a second slave node in electrical communication with the master node and a second loudspeaker, wherein the second slave node is AC coupled to the standard two-wire speaker wire in series with the first slave node,

wherein the master node is operable to transmit an identifier with the control signal in the data signals, wherein the identifier identifies one of the first slave node and the second slave node, wherein the first slave node and the second slave node are operable to respond to the control signal such that if the control signal indicates the first slave node, the first slave node is responsive to the control signal and the second slave node is not responsive to the control signal, and wherein the first slave node and the second slave node are operable to respond to the control signal such that if the control signal indicates the second slave node, the second slave node is responsive to the control signal and the first slave node is not responsive to the control signal.

3. The communication system of claim 1 wherein a data signal of the data signals includes a preamble section and a data payload section.

4. The communication system of claim 1 wherein a data signal of the data signals includes a preamble section and a data payload section, wherein the preamble section includes a pulse amplitude modulated waveform.

5. The communication system of claim 1 wherein a data signal of the data signals includes a preamble section and a data payload section, wherein the data payload section includes a combination of Manchester encoding and pulse width variations.

6. The communication system of claim 1 wherein a data signal of the data signals includes a preamble section and a data payload section, wherein preamble pulses in the preamble section have a wider pulse width than data pulses in the data payload section.

7. The communication system of claim 1 wherein a data signal of the data signals includes a preamble section and a data payload section, wherein the data payload section starts at a fixed time location relative to a start of a first preamble pulse in the preamble section.

8. The communication system of claim 1 wherein the master node further comprises a high-frequency power transmitter operable to place a power signal on the analog signal path at frequencies above audio frequencies, and wherein the slave node further comprises a power recovery circuit operable to receive the power signal from the master node and to use the power signal to power the slave node.

9. The communication system of claim 1 wherein the master node further comprises a high-frequency power transmitter operable to place a power signal on the analog signal path at frequencies above audio frequencies, wherein the slave node further comprises a power recovery circuit operable to receive the power signal from the master node and to use the power signal to power the slave node, wherein the data signals comprise uplink data signals, and wherein the uplink data signals are combined with the power signal.

10. The communication system of claim 1 wherein the data signals comprise uplink data signals, wherein the master node is operable to receive downlink data signals from the slave node and to pass data in the downlink data signals to the audio equipment.

11. The communication system of claim 1 wherein the data signals comprise uplink data signals, wherein the data transceiver of the slave node is further operable to transmit downlink data signals to the master node, and wherein the master node is operable to receive the downlink data signals from the slave node and to pass data in the downlink data signals to the audio equipment.

12. The communication system of claim 1 further comprising multiple loudspeakers connected in series via the standard two-wire speaker wire to the audio equipment, each loudspeaker of the multiple loudspeakers having an associated slave node operable to communicate with the master node.

13. The communication system of claim 1 wherein the slave node derives the necessary power to operate from the analog signal path.

14. The communication system of claim 1 wherein the master node further includes an interface with the audio equipment, and wherein the master node is operable to receive downlink data signals from the slave node and to pass data in the downlink data signals to the audio equipment via the interface.

15. The communication system of claim 1 wherein the master node further includes an interface with the audio equipment, wherein the master node is operable to receive downlink data signals from the slave node and to pass data in the downlink data signals to the audio equipment via the interface, and wherein the audio equipment is operable to adjust signal processing components of the analog audio signal in response to the downlink data signals from the slave node.

16. The communication system of claim 1 wherein the audio equipment includes a digital signal processor for loudspeaker processing and equalization using the data signals from the master node and downlink data signals from the slave node.

17. A method of communicating between audio equipment and a loudspeaker comprising:

connecting the loudspeaker and the audio equipment over a standard two-wire speaker wire operable to carry an analog audio signal, wherein the analog audio signal is a high-voltage, high-current analog audio signal;

providing a master node in electrical communication with an analog signal path carrying the analog audio signal between the audio equipment and the loudspeaker, wherein the master node is alternating current (AC) coupled to the standard two-wire speaker wire, wherein the master node includes a data encoder operable to encode data signals, and a data transceiver operable to place the data signals onto the analog audio signal at frequencies above audio frequencies;

providing a slave node in electrical communication with the master node and the loudspeaker, wherein the slave node is AC coupled to the standard two-wire speaker wire, wherein the slave node includes a data transceiver operable to receive the data signals from the master node, a data decoder and an interface able to communicate with electronics in the loudspeaker, wherein the analog signal path is able to simultaneously transmit both the analog audio signal and the data signals;

receiving, by the slave node, a control signal in the data signals from the master node; and

controlling, by the slave node responsive to the control signal, a parameter of the electronics in the loudspeaker.

18. The method of claim 17 wherein the loudspeaker comprises a first loudspeaker, wherein the slave node comprises a first slave node, the method further comprising:

providing a second slave node in electrical communication with the master node and a second loudspeaker, wherein the second slave node is AC coupled to the standard two-wire speaker wire in series with the first slave node;

transmitting, by the master node, an identifier with the control signal in the data signals, wherein the identifier identifies one of the first slave node and the second slave node;

responding, by one of the first slave node and the second slave node, to the control signal such that if the control signal indicates the first slave node, the first slave node is responsive to the control signal and the second slave node is not responsive to the control signal, and such that if the control signal indicates the second slave node, the second slave node is responsive to the control signal and the first slave node is not responsive to the control signal.

19. An audio system comprising:

audio equipment that is operable to generate an analog audio signal;

a loudspeaker that is operable to receive the analog audio signal and to generate an audio output;

a standard two-wire speaker wire that connects the audio equipment and the loudspeaker, and is operable to carry the analog audio signal, wherein the analog audio signal is a high-voltage, high-current analog audio signal;

a master node in electrical communication with an analog signal path carrying the analog audio signal between the audio equipment and the loudspeaker, wherein the master node is alternating current (AC) coupled to the standard two-wire speaker wire, wherein the master node includes a data encoder operable to encode data signals, and a data transceiver operable to place the data signals onto the analog audio signal at frequencies above audio frequencies; and

a slave node in electrical communication with the master node and the loudspeaker, wherein the slave node is AC coupled to the standard two-wire speaker wire, wherein the slave node includes a data transceiver operable to receive the data signals from the master node, a data decoder and an interface able to communicate with electronics in the loudspeaker, wherein the analog signal path is able to simultaneously transmit both the analog audio signal and the data signals,

wherein the slave node is operable to receive a control signal in the data signals from the master node, and responsive to the control signal, to control a parameter of the electronics in the loudspeaker.

20. The audio system of claim 19 wherein the loudspeaker comprises a first loudspeaker, wherein the slave node comprises a first slave node, the audio system further comprising:

a second slave node in electrical communication with the master node and a second loudspeaker, wherein the second slave node is AC coupled to the standard two-wire speaker wire in series with the first slave node,

wherein the master node is operable to transmit an identifier with the control signal in the data signals, wherein the identifier identifies one of the first slave node and the second slave node, wherein the first slave node and the second slave node are operable to respond to the control signal such that if the control signal indicates the first slave node, the first slave node is responsive to the control signal and the second slave node is not responsive to the control signal, and wherein the first slave node and the second slave node are operable to respond to the control signal such that if the control signal indicates the second slave node, the second slave node is responsive to the control signal and the first slave node is not responsive to the control signal.