Method to increase performance of secondary data in a hierarchical modulation scheme

• US 20050111579A1
• Filed: 05/18/2004
• Published: 05/26/2005
• Est. Priority Date: 11/26/2003
• Status: Active Grant

• Current Assignee: Aptiv Technologies AG (Aptiv PLC)
• Original Assignee: Delphi Technologies, Inc. (Aptiv PLC)
• Inventors: Dibiaso, Eric A., Walker, Glenn A., Hiatt, Michael L. Jr.
• Granted Patent: US 7,230,998 B2
• Time in Patent Office: Days
• US Class Current: 375/308
• CPC Class Codes: H04B 7/18513 Transmission in a satellite or space-based system
• CPC Class Codes: H04L 27/3466 by providing an alternative to one signal point
• CPC Class Codes: H04L 27/3488 Multiresolution systems

Abstract

The present invention provides a receiver for use in a SDAR system, the receiver including a receiving unit having satellite signal detection means for detecting a first transmit signal transmitted from a first communication satellite and a second transmit signal transmitted from a second communication satellite, the first transmit signal produced when the transmitter modulates a primary data stream with a secondary data stream on a first carrier wave associated with the first communication satellite and the second transmit signal produced when the transmitter modulates the primary and secondary data streams on a second carrier wave associated with the second communication satellite; and at least one demodulator coupled to the receiving unit and configured to demodulate the at least one of the first and the second transmit signals.

Claims

1. In a digital data transmission system including a transmitter for transmitting transmit signals, a receiver comprising:

a receiving unit including satellite signal detection means for detecting a first transmit signal transmitted from a first communication satellite and a second transmit signal transmitted from a second communication satellite, the first transmit signal produced when the transmitter modulates a primary data stream with a secondary data stream on a first carrier wave associated with the first communication satellite and the second transmit signal produced when the transmitter modulates the primary and secondary data streams on a second carrier wave associated with the second communication satellite; and

at least one demodulator coupled to said receiving unit and configured to demodulate at least one of the first and the second transmit signals.

2. The receiver of claim 1 wherein said receiving unit further includes a terrestrial signal detection means for detecting a third transmit signal transmitted from a terrestrial repeater, the third transmit signal produced when the terrestrial repeater receives at least one of the first and the second transmit signals and modulates the primary data stream with the secondary data stream on a third carrier wave associated with the terrestrial repeater.

3. The receiver of claim 2 wherein said at least one demodulator is configured to demodulate the third transmit signal.

4. The receiver of claim 1 wherein the satellite signal detection means include a first antenna in communication with a first tuner unit for receiving at least one of the first and the second transmit signals, wherein the first transmit signal is produced when the transmitter modulates the primary and the secondary data on the first carrier wave using a M-PSK modulating scheme, and the second transmit signal is produced when the transmitter modulates the primary and the secondary data on the second carrier wave using a M-PSK modulating scheme.

5. The receiver of claim 2 wherein the terrestrial signal detection means include one of the first antenna in communication with the first tuner unit and a second antenna in communication with a second tuner unit for receiving the third transmit signal, wherein the third transmit signal is produced when the primary and the secondary data are re-encoded on the third carrier wave using an OFDM modulation scheme, the OFDM modulation scheme dividing the third carrier wave into multiple sub-carrier waves each having one of a M-PSK, D-MPSK and pi/4 D-MPSK modulation scheme.

6. The receiver of claim 1 wherein said receiving unit is operable to receive the first and the second transmit signals including primary data comprising one of QPSK, D-QPSK and pi/4 D-QPSK modulated data.

7. The receiver of claim 1 wherein said receiving unit is operable to receive the first and the second transmit signals including secondary data comprising modulated data in the form of a phase offset relative to the modulated primary data.

8. The receiver of claim 7 wherein said receiving unit is operable to receive the first and the second transmit signals including secondary data comprising BPSK modulated data.

9. The receiver of claim 7 wherein said receiving unit is operable to receive the first and the second transmit signals including primary data encoded with a first number of information bits per symbol.

10. The receiver of claim 9 wherein said receiving unit is operable to receive the first and the second transmit signals including secondary data encoded with a second number of information bits per symbol lower than the first number of information bits.

11. The receiver of claim 10 wherein said receiving unit is operable to receive the first and the second transmit signals including primary data encoded with 2 bits per symbol.

12. The receiver of claim 11 wherein said receiving unit is operable to receive the first and the second transmit signals including secondary data encoded with 1 bit per symbol.

13. The receiver of claim 1 wherein said receiving unit is operable to receive the first and the second transmit signals comprising uniform 8-PSK modulated data.

14. The receiver of claim 1 wherein said receiving unit is operable to receive the first and the second transmit signals comprising non-uniform 8-PSK modulated data.

15. The receiver of claim 1 wherein said receiving unit is operable to receive the first and the second transmit signals comprising Gray coded 8-PSK modulated data.

16. The receiver of claim 12 wherein said receiving unit is operable to receive the third transmit signal encoded with a third number of information bits per symbol, the third number of information bits per symbol greater than the first and the second numbers of bits per symbol.

17. The receiver of claim 16 wherein said receiving unit is operable to receive the third transmit signal encoded with 3 bits per symbol.

18. The receiver of claim 2 wherein said receiving unit is operable to receive the third transmit signal comprising OFDM modulated data.

19. The receiver of claim 7 wherein said receiving unit is operable to receive the first and the second transmit signals including secondary data spread over multiple symbols.

20. The receiver of claim 7 wherein said receiving unit is operable to receive the first and the second transmit signals including secondary data spread over a multiple of 2 symbols.

21. The receiver of claim 19 wherein said receiving unit is operable to receive the first and the second transmit signals including secondary data encoded to ensure a zero mean offset over the multiple symbols such that for each positive phase offset, there is a corresponding negative phase offset.

22. The receiver of claim 1 wherein said receiving unit is operable to receive the first and the second transmit signals including primary data and secondary data, wherein the primary data is encoded with a different forward error correction algorithm than the secondary data.

23. The receiver of claim 22 wherein said receiving unit is operable to receive the first and the second transmit signals, the signals including primary data encoded with one of a block forward error correction algorithm and a convolutional forward error correction algorithm and secondary data encoded with one of a turbo coding forward error correction algorithm and a low density parity check coding forward error correction algorithm.

24. A method of receiving transmitted data, the method comprising the steps of:

detecting a first transmit signal, the first transmit signal transmitted from a first communication satellite and comprising a first level data and a second level data modulated on a first carrier wave associated with the first communication satellite;

detecting a secorid transmit signal, the second transmit signal transmitted from a second communication satellite and comprising the first level data and the second level data modulated on a second carrier wave associated with the second communication satellite;

interpreting the first transmit signal; and

providing the interpreted signal to an output unit.

25. The method of claim 24 wherein said step of detecting includes a step of detecting a third transmit signal, the third transmit signal transmitted from a terrestrial repeater and comprising the first level data and the second level data re-encoded on a third carrier wave associated with the terrestrial repeater.

26. The method of claim 25 wherein said step of interpreting includes a step of interpreting at least one of the first, second and the third transmit signals.

27. The method of claim 25 further comprising a step of demodulating the first and the second transmit signals, wherein

the first level data comprises one of QPSK, D-QPSK and pi/4 D-QPSK modulated data and includes a first number of information bits per symbol;

and

the second level data comprises BPSK modulated data in the form of a phase offset relative to the first level data and includes a second number of information bits that is lower than the first number of information bits.

28. The method of claim 25 further comprising the steps of:

demodulating the first transmit signal, the step of demodulating including a step of demodulating the first carrier signal, wherein the first and the second level data is M-PSK modulated on the first carrier wave, the first carrier wave comprising one of uniform 8-PSK modulated data, non-uniform 8-PSK modulated data and Gray coded 8-PSK modulated data; and

demodulating the second transmit signal, the step of demodulating including a step of demodulating the second carrier wave, wherein the first and the second level data is M-PSK modulated on the first carrier wave, the second carrier wave comprising one of 8-PSK modulated data, non-uniform 8-PSK modulated data and Gray coded 8-PSK modulated data.

29. The method of claim 25 further comprising a step of demodulating the third transmit signal, the step of demodulating including a step of demodulating the third carrier wave, wherein the first and the second level data is re-encoded with a third number of information bits per symbol in an OFDM format on the third carrier wave, the third number of information bits being greater than the first number of information bits per symbol.

30. The method of claim 24 further comprising the step of retrieving the first and the second level data, the second level data spread over multiple symbols.

31. The method of claim 30 wherein the step of detecting includes a step of decoding the first and the second level data, the first and the second level data encoded using different forward error correction schemes, wherein the first level data is encoded using one of a block forward error correction algorithm and a convolutional forward error correction algorithm, and the second level data is encoded using one of a turbo coding forward error correction algorithm and a low density parity check coding forward error correction algorithm.

32. In a digital data transmission system including a transmitter for transmitting signals, a terrestrial repeater comprising:

a receiving unit for detecting a first transmit signal and a second transmit signal, the first transmit signal transmitted from a first communication satellite and produced when the transmitter modulates a primary and a secondary data on a first carrier wave associated with the first communication satellite, and the second transmit signal transmitted from a second communication satellite and produced when the transmitter modulates the primary and the secondary data on a second carrier wave associated with the second communication satellite;

an encoder for re-encoding the primary and the secondary data on a third carrier wave to form a third transmit signal; and

a re-transmitter for transmitting the third transmit signal to a receiver.

33. The repeater of claim 32 wherein said receiving unit includes an antenna in communication with a tuner unit for receiving the first and the second transmit signals, wherein the primary and the secondary data are modulated on the first and the second carrier waves using a M-PSK modulating scheme.

34. The repeater of claim 33 wherein said receiving unit is adapted to receive the first and the second transmit signals, the first and the second transmit signals including primary data comprising one of QPSK, D-QPSK and pi/4 D-QPSK modulated data.

35. The repeater of claim 34 wherein said receiving unit is adapted to receive the first and the second transmit signals, the first and the second transmit signals including secondary data comprising modulated data in the form of a phase offset relative to the modulated primary data.

36. The repeater of claim 35 wherein said receiving unit is adapted to receive the first and the second transmit signals, the first and the second transmit signals including secondary data comprising BPSK modulated data.

37. The repeater of claim 35 wherein said receiving unit is adapted to receive the first and the second transmit signals, the first and the second transmit signals including the modulated primary data, wherein the primary data is encoded with a first number of information bits per symbol.

38. The repeater of claim 37 wherein said receiving unit is adapted to receive the first and the second transmit signals, the first and the second transmit signals including the modulated secondary data, wherein the secondary data is encoded with a second number of information bits per symbol that is lower than the first number of information bits.

39. The repeater of claim 37 wherein said receiving unit is adapted to receive the first and the second transmit signals, the first and the second transmit signals including the modulated primary data encoded with 2 bits per symbol.

40. The repeater of claim 38 wherein said receiving unit is adapted to receive the first and the second transmit signals, the first and the second transmit signals including the modulated secondary data encoded with the 1 bit per symbol.

41. The repeater of claim 32 wherein said receiving unit is adapted to receive the first and the second transmit signals, the first and the second transmit signals each comprising 8-PSK modulated data.

42. The repeater of claim 32 wherein said receiving unit is adapted to receive the first and the second transmit signals, the first and the second transmit signals each comprising non-uniform 8-PSK modulated data.

43. The repeater of claim 32 wherein said receiving unit is adapted to receive first and the second transmit signals, the first and the second transmit signals each comprising Gray coded 8-PSK modulated data.

44. The repeater of claim 37 wherein said receiving unit is adapted to receive the third transmit signal encoded with a third number of information bits per symbol, the third number of information bits per symbol greater than the first and the second numbers of information bits per symbol.

45. The repeater of claim 44 wherein said receiving unit is adapted to receive the third transmit signal encoded with 3 bits per symbol.

46. The repeater of claim 32 wherein said receiving unit is adapted to receive the third transmit signal, the third transmit signal comprising OFDM modulated data.

47. The repeater of claim 34 wherein said receiving unit is adapted to receive the first and the second transmit signals, the first and the second transmit signals each including secondary data spread over multiple symbols.

48. The repeater of claim 47 wherein said receiving unit is adapted to receive the first and the second transmit signals, the first and the second transmit signals each including secondary data spread over a multiple of 2 symbols.

49. The repeater of claim 47 wherein said receiving unit is adapted to receive the first and the second transmit signals, the first and the second transmit signals each including secondary data encoded to ensure a zero mean offset over the multiple symbols such that for each positive phase offset, there is a corresponding negative phase offset.

50. The repeater of claim 32 wherein said receiving unit is adapted to receive the first and the second transmit signals including primary data and secondary data, wherein the primary data is encoded with a different forward error correction algorithm than the secondary data.

51. The repeater of claim 49 wherein said receiving unit is adapted to receive the first and the second transmit signals, said signals including primary data encoded with one of a block forward error correction algorithm and a convolutional forward error correction algorithm and secondary data encoded with one of a turbo coding forward error correction algorithm and a low density parity check coding forward error correction algorithm.

52. In a satellite audio radio service system, a method for receiving transmitted data, the method comprising the steps of:

receiving a primary data stream and a secondary data stream from both a first communication satellite and a second communication satellite, the primary data stream having a first data rate and the secondary data stream having a second data rate;

determining the validity of said first and said second data streams; and

hierarchically modulating the primary and the secondary data streams to form a combined data stream when the secondary data stream is determined to be an enhancement to the primary data stream, wherein the combined data stream has a third data rate greater than the first data rate.

53. The method of claim 52 further comprising the steps of interpreting the combined data signal and providing the information to an output unit.