Method and apparatus for transmitting audio and non-audio information with error correction

• US 20040253925A1
• Filed: 07/19/2004
• Published: 12/16/2004
• Est. Priority Date: 08/13/2001
• Status: Active Grant

• Current Assignee: Thomson Licensing (Vantiva SA)
• Original Assignee: Thomson Licensing (Vantiva SA)
• Inventors: Cheah, Sin Hui, Caffrey, John Justin, Rehm, Norbert Joseph III, Friedline, Karl Lewis
• Granted Patent: US 7,171,156 B2
• Time in Patent Office: Days
• US Class Current: 455/63.1
• CPC Class Codes: G11B 2020/10546 specifically adapted for audio data
• CPC Class Codes: H04L 1/0041 Arrangements at the transmitter end
• CPC Class Codes: H04L 1/0045 Arrangements at the receiver end
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence

Abstract

A method and an apparatus for providing digital quality transmission of audio and non-audio information using low cost components and arrangement. The present invention provides for the transmission of the audio and non-audio transmission by first converting the data to conform to the CD standard format and conditioning the converted signal to thereby generate a conditioned EFM signal. The conditioned EFM signal is used to frequency modulate a carrier. By converting the audio and non-audio information to conform to the CD standard format, the present method provides a low cost means of transmitting the data with error detection and correction. Another aspect of the present invention relates to embedding the non-audio information in the SUBCODE block of the data frame according to the CD standard. The non-audio information may be unrelated to the audio information, and the audio and non-audio information may be transmitted to separate devices. Another aspect of the present invention relates to controlling a voltage controlled oscillator in response to the fill level of a file buffer in the decoder.

Claims

1. A method for wirelessly transmitting audio information, comprising the steps of:

generating a digital bitstream representative of the audio information;

formatting the digital bitstream to comprise a plurality of data frames;

generating error correction bits associated with the respective frames, and embedding the error correction bits into the respective frames;

interleaving the data frames;

EFM encoding the bitstream to generate an EFM signal;

conditioning the EFM signal to generate a conditioned signal comprising sinusoid modulation tones; and

modulating a carrier signal using the conditioned EFM signal.

2. The method according to claim 1, wherein the formatting, generating, interleaving, and EFM encoding steps comprise, formatting, generating, interleaving, and EFM encoding the bitstream to generate a Red Book CD standard compliant signal.

3. The method according to claim 2, wherein the conditioning step comprises bandwidth limiting the EFM signal.

4. The method according to claim 2, further comprising the steps of:

receiving non-audio digital data;

embedding the non-audio digital data in the SUBCODE block of the data frames, wherein the error correction bits are used for error detection by a receiving unit.

5. The method according to claim 4, wherein the embedding step comprises embedding the non-audio digital data in a predetermined number of data frames.

6. The method according to claim 4, wherein the receiving step comprises receiving the non-audio digital data from a signal source different than audio information signal source.

7. The method according to claim 4, wherein the receiving step comprises receiving the non-audio digital data from the Internet.

8. The method according to claim 4, wherein the receiving step comprises receiving non-audio digital data that includes a destination ID associated with a particular one of a plurality of receiving units.

9. The method according to claim 4, wherein the embedding step comprises embedding 6 bits at a time of the non-audio digital data into each SUBCODE block of each data frame.

10. A method for receiving and processing audio information transmitted via a wireless channel, comprising the steps of:

receiving an audio signal via a wireless channel;

demodulating the received audio signal to recover a bandwidth limited EFM signal;

decoding the EFM signal to generate a data bitstream comprising a plurality of data frames;

deinterleaving the data in the data frames to generate a plurality of deinterleaved data frames;

performing error correction in response to error correction codes included in the respective data frames;

A/D converting the deinterleaved data frames to generate an analog output signal substantially free from transmission impairments.

11. The method according to claim 10, wherein the demodulating, decoding, deinterleaving, and error correcting steps comprise demodulating, decoding, deinterleaving, and error correcting in accordance with the Red Book CD standard.

12. The method according to claim 10, further comprising the step of

extracting non-audio digital data from a SUBCODE block of a data frame, and wherein the error correction step consists of performing error detection in response to the error correction codes.

13. The method according to claim 12, further comprising the step of

extracting a data packet from a plurality of SUBCODE blocks associated with a plurality of data frames.

14. The method according to claim 13, further comprising the step of extracting a destination ID from the extracted data packet, and processing the data packet in response to the destination ID.

15. The method according to claim 14, further comprising the step of storing the extracted data packet in a storage device in response to the destination ID.

16. The method according to claim 14, further comprising the step of displaying a predetermined display while presenting the audio information in response to the extracted data packet.

17. The method according to claim 10, further comprising the step of providing a file buffer for temporarily storing the received bitstream during the demodulating, decoding, deinterleaving and error correcting steps, wherein the file buffer provides a PCM signal representative of the fill level in the file buffer.

18. The method according to claim 17, further comprising the step of controlling a voltage controlled oscillator associated with a decoder in response to the PCM signal representative of the fill level in the file buffer, whereby the decoding rate of the received signal is controlled in response to the fill level of the file buffer.