Wireless RF link for uncompressed transmission of HDTV signals

• US 20040196920A1
• Filed: 04/03/2003
• Published: 10/07/2004
• Est. Priority Date: 04/03/2003
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Loheit, Kurt W., Salter, William A.
• Granted Patent: US 7,139,319 B2
• Time in Patent Office: Days
• US Class Current: 375/281
• CPC Class Codes: H03C 3/40 using two signal paths the outputs of which have a predetermined phase difference and at least one output being amplitude-modulated
• CPC Class Codes: H04N 7/015 High-definition television systems

Abstract

A method for transmitting and receiving an uncompressed HDTV signal over a wireless RF link includes steps of: providing a clock signal synchronized to the uncompressed HDTV signal; and providing a stream of regenerated data from the uncompressed HDTV signal, with the clock signal synchronized to the stream of regenerated data. The clock signal is then used for demultiplexing the stream of regenerated data into an I data stream and a Q data stream. The method further includes steps of: modulating a carrier with the I data stream and the Q data stream; transmitting the carrier over the wireless RF link; demodulating the carrier so that the I data stream and the Q data stream are recovered; multiplexing the I data stream and the Q data stream into a single stream of HDTV data; and recovering the uncompressed HDTV signal from the single stream of HDTV data.

Claims

1. A method for transmitting and receiving an uncompressed HDTV signal over a wireless RF link, comprising steps of:

providing a clock signal synchronized to the uncompressed HDTV signal;

providing a stream of regenerated data from the uncompressed HDTV signal, said clock signal synchronized to said stream of regenerated data;

demultiplexing said stream of regenerated data, using said clock signal, into an I data stream and a Q data stream;

modulating a carrier with said I data stream and said Q data stream;

transmitting said carrier in a signal over the wireless RF link;

demodulating said carrier so that said I data stream and said Q data stream are recovered;

multiplexing said I data stream and said Q data stream into a single stream of HDTV data; and

recovering the uncompressed HDTV signal from said single stream of HDTV data.

2. The method of claim 1, further comprising steps of:

encoding said stream of regenerated data, producing a stream of encoded data; and

providing a second clock signal synchronized to said stream of encoded data; and

wherein said demultiplexing step comprises;

demultiplexing said stream of encoded data, using said second clock signal, into said I data stream and said Q data stream.

3. The method of claim 1, wherein said step of providing said clock signal synchronized to the uncompressed HDTV signal comprises using edge detection of said uncompressed HDTV signal to generate said clock signal.

4. The method of claim 1, wherein said step of providing said clock signal synchronized to the uncompressed HDTV signal comprises using a “

times-2”

multiplier with said uncompressed HDTV signal to generate said clock signal.

5. The method of claim 2, wherein said step of providing said second clock signal synchronized to said stream of encoded data comprises using a PLL to generate said second clock signal.

6. The method of claim 2, wherein said step of encoding said stream of regenerated data comprises forward error correction coding.

7. The method of claim 1, wherein said step of modulating said carrier comprises QPSK modulation of said carrier by said I data stream and said Q data stream.

8. The method of claim 1, wherein said step of transmitting said carrier comprises upconverting said carrier to said signal having a higher frequency.

9. The method of claim 1, further comprising a step of down converting said carrier to an IF frequency.

10. The method of claim 1, wherein said step of recovering the uncompressed HDTV signal comprises decoding said single stream of HDTV data.

11. A method for transmitting an uncompressed HDTV signal over a wireless RF link, comprising steps of:

providing a stream of regenerated data from the uncompressed HDTV signal;

providing a first clock signal synchronized to said stream of regenerated data;

encoding said stream of regenerated data, producing a stream of encoded data;

providing a second clock signal synchronized to said stream of encoded data;

demultiplexing said stream of encoded data, using said second clock signal, into an I data stream and a Q data stream;

modulating a carrier with said I data stream and said Q data stream; and

transmitting said carrier in a signal over the wireless RF link.

12. The method of claim 11, wherein:

said step of encoding said stream of regenerated data comprises using a forward error correction code;

said stream of regenerated data has a first data rate of 1.485 Gbps;

said stream of encoded data has a second data rate higher than said first data rate by a coding overhead of said forward error correction code; and

said second clock signal has a rate higher than said first clock signal by said coding overhead.

13. The method of claim 11, wherein said step of providing said first clock signal synchronized to said stream of regenerated data comprises using edge detection of said stream of regenerated data to generate said first clock signal.

14. The method of claim 11, wherein said step of providing said first clock signal synchronized to said stream of regenerated data comprises using a “

times-2”

multiplier with said stream of regenerated data to generate said first clock signal.

15. The method of claim 11, wherein said step of providing said second clock signal is performed using a PLL that synchronizes said second clock signal to said stream of encoded data.

16. The method of claim 11, wherein said step of encoding said stream of regenerated data comprises Reed-Solomon forward error correction coding.

17. The method of claim 11, wherein said step of modulating said carrier comprises QPSK modulation of an IF carrier by said I data stream and said Q data stream and frequency upconversion of said IF carrier to said carrier.

18. The method of claim 11, wherein said step of transmitting said carrier in said signal comprises transmitting said signal with a circular polarization.

19. A method for receiving an uncompressed HDTV signal over a wireless RF link, comprising steps of:

receiving a carrier in a signal over the wireless RF link;

demodulating said carrier so that said I data stream and said Q data stream are recovered;

multiplexing said I data stream and said Q data stream into a single stream of encoded HDTV data; and

decoding said single stream of encoded HDTV data so that the uncompressed HDTV signal is recovered.

20. The method of claim 19, further comprising a step of:

generating a clock signal from said I data stream and said Q data stream, said clock signal synchronized to said I data stream and said Q data stream; and

wherein said multiplexing step comprises;

using said clock signal as a timing source to multiplex said I data stream and said Q data stream into said single stream of encoded HDTV data.

21. The method of claim 20, wherein said clock signal provides a timing source for decoding said single stream of encoded HDTV data.

22. The method of claim 19, further comprising a step of down converting said signal to a carrier having an IF frequency greater than 1.5 GHz and less than 6 GHz.

23. The method of claim 19, further comprising steps of:

separating an LHCP signal from an RHCP signal;

recovering a first uncompressed HDTV signal from said LHCP signal; and

recovering a second uncompressed HDTV signal from said RHCP signal.

25. The method of claim 19, further comprising steps of:

transmitting a first uncompressed HDTV signal using an LHCP signal;

transmitting a second uncompressed HDTV signal using an RHCP signal;

separating said LHCP signal from said RHCP signal using an ortho-mode transducer at a receiver;

recovering said first uncompressed HDTV signal from said LHCP signal; and

recovering said second uncompressed HDTV signal from said RHCP signal.

24. A method for transmitting and receiving an uncompressed HDTV signal over a wireless RF link, comprising steps of:

providing a stream of regenerated data having a first data rate of 1.485 Gbps from the uncompressed HDTV signal;

providing a first clock signal using edge detection of said stream of regenerated data to generate said first clock signal synchronized to said stream of regenerated data;

encoding said stream of regenerated data using a forward error correction code, producing a stream of encoded data having a second data rate higher than said first data rate by a coding overhead of said forward error correction code;

providing a second clock signal using a PLL to generate said second clock signal synchronized to said stream of encoded data, said second clock signal having a rate higher than said first clock signal by said coding overhead;

demultiplexing said stream of encoded data, using said second clock signal, into an I data stream and a Q data stream;

QPSK modulating an IF carrier by said I data stream and said Q data stream;

up converting said IF carrier to an RF signal;

transmitting said RF signal over the wireless RF link;

receiving said RF signal over the wireless RF link;

down converting said RF signal to an IF frequency carrier having frequency greater than 1.5 GHz and less than 6 GHz;

demodulating said IF frequency carrier so that said I data stream and said Q data stream are recovered;

generating a third clock signal from said I data stream and said Q data stream, said third clock signal synchronized to said I data stream and said Q data stream;

multiplexing said I data stream and said Q data stream, using said third clock signal, into a single stream of encoded HDTV data; and

decoding said single stream of encoded HDTV data, using said third clock signal, so that the uncompressed HDTV signal is recovered.

26. A method of providing a wireless RF link for an HDTV system, comprising steps of:

performing data regeneration on an uncompressed HDTV signal, producing a stream of regenerated HDTV data;

synchronizing a first clock signal to said stream of regenerated HDTV data;

encoding said stream of regenerated HDTV data, producing a stream of encoded data;

synchronizing a second clock signal to said stream of encoded data;

demultiplexing said stream of encoded data, using said second clock signal, into an I data stream and a Q data stream;

modulating a carrier by said I data stream and said Q data stream;

transmitting said carrier in a signal over the wireless RF link;

receiving said signal over the wireless RF link;

demodulating said carrier so that said I data stream and said Q data stream are recovered;

generating a third clock signal from said I data stream and said Q data stream, said third clock signal synchronized to said I data stream and said Q data stream;

using said third clock signal to multiplex said I data stream and said Q data stream into a single stream of HDTV data; and

decoding said single stream of HDTV data so that said uncompressed HDTV signal is recovered.

27. The method of claim 26, wherein

said stream of regenerated data has a data rate of 1.485 Gbps;

and

said step of synchronizing said first clock signal to said stream of regenerated HDTV data comprises using edge detection of said stream of regenerated HDTV data to generate said first clock signal.

28. The method of claim 26, wherein:

said step of encoding said stream of regenerated HDTV data comprises using a forward error correction code; and

said stream of encoded data has a second data rate higher than 1.485 Gbps by a coding overhead of said forward error correction code; and

said second clock signal has a rate higher than said first clock signal by said coding overhead.

29. The method of claim 26, wherein said step of synchronizing said first clock signal to said stream of regenerated HDTV data comprises using a “

times-2”

multiplier with said stream of regenerated HDTV data to generate said first clock signal.

30. The method of claim 26, wherein said step of synchronizing said second clock signal comprises using a PLL synchronized to said stream of encoded data to generate said second clock signal.

31. The method of claim 26, wherein said step of encoding said stream of regenerated data comprises turbo product coding.

32. The method of claim 26, wherein said step of modulating said carrier comprises using a higher order of modulation of said carrier by said I data stream and said Q data stream.

33. The method of claim 26, wherein said step of modulating said carrier comprises 16 QAM modulation of said carrier by said I data stream and said Q data stream.

34. The method of claim 26, wherein said third clock signal is used as a timing source for decoding said single stream of HDTV data.

35. The method of claim 26, wherein said step of receiving said signal comprises down converting said signal to said carrier having an IF frequency greater than 1.5 GHz and less than 6 GHz.

36. The method of claim 26, further comprising steps of:

transmitting a first signal with LHCP over said wireless RF link;

transmitting a second signal with RHCP over said wireless RF link;

separating said first signal from said second signal using an ortho-mode transducer at a receiver;

recovering a first uncompressed HDTV signal from said first signal; and

recovering a second uncompressed HDTV signal from said second signal.