Granted Patent B2

US 9,203,492 · App. 14/137,665 · Granted Dec 1, 2015

Abstract

Claims (49)

1. A method for implementing Low Density Parity Check (LDPC) codes in an IEEE 802.11 standard system configured to operate in a Multiple-Input, Multiple-Output schema, and encoding an input information stream with the LDPC codes, comprising:

a) defining a base LDPC code, having a length equal to an integer multiple of a number of data carriers in an Orthogonal Frequency Division Multiplexing (OFDM) symbol;

b) transmitting the base LDPC code in place of a space-time code over a plurality of sub-carriers, wherein the base LDPC code is transmitted at an expected phase on sub-carriers specified by the IEEE 802.11 standard system, and

c) transmitting the base LDPC code in place of the space-time code on other sub-carriers than those specified by the IEEE 802.11 standard system, wherein the base LDPC code on the other sub-carriers is transmitted offset in phase from the base LDPC code on the specified sub-carriers.

2. The method of claim 1 , wherein the base LDPC code is 192 bits long.

3. The method of claim 2 , further comprising using a longer LDPC code instead of the base LDPC code, wherein a length of the longer LDPC code is an integer multiple of the base LDPC code.

4. The method of claim 3 , further comprising transmitting bits of the longer LDPC code sequentially on the plurality of sub-carriers and the other sub-carriers.

5. The method of claim 2 , wherein the plurality of sub-carriers are transmitted by a first transmission antenna and the other sub-carriers are transmitted by at least one other antenna.

6. The method of claim 1 , further comprising using a longer LDPC code instead of the base LDPC code, wherein a length of the longer LDPC code is an integer multiple of the base LDPC code.

7. The method of claim 6 , further comprising transmitting bits of the longer LDPC code sequentially on the plurality of sub-carriers and the other sub-carriers.

8. The method of claim 1 , wherein the plurality of sub-carriers are transmitted by a first transmission antenna and the other sub-carriers are transmitted by at least one other antenna.

9. A Low Density Parity Check coded, IEEE 802.11 compatible Multiple-Input, Multiple-Output (MIMO) broadcast system, comprising:

an encoder to receive a base LDPC code having a length equal to an integer multiple of a number of data carriers in an OFDM symbol instead of a space-time code, and to encode information bits using the LDPC code;

a modulator, coupled to the encoder, to modulate the encoded information bits;

a transmitter, coupled to the modulator, to transmit the modulated encoded information bits on a plurality of transmit antennas, wherein the modulated encoded information bits are transmitted on sub-carriers specified by an IEEE 802.11 standard system.

10. The LDPC coded, IEEE 802.11 compatible MIMO broadcast system of claim 9 , further comprising:

a plurality of receive antennas to receive the transmitted modulated encoded information bits;

a detector, coupled to the antennas, to detect the presence of the transmitted modulated encoded information bits;

an LDPC decoder, coupled to the detector, to decode the transmitted modulated encoded information bits; and

a demodulator, coupled to the LDPC decoder, to demodulate the transmitted modulated encoded information bits.

11. The LDPC coded, IEEE 802.11 compatible MIMO broadcast system of claim 10 , wherein the base LDPC code is 192 bits long.

12. The LDPC coded, IEEE 802.11 compatible MIMO broadcast system of claim 11 , further comprising using a longer LDPC code instead of the base LDPC code, wherein a length of the longer LDPC code is an integer multiple of the base LDPC code.

13. The LDPC coded, IEEE 802.11 compatible MIMO broadcast system of claim 12 , further comprising bits of the longer LDPC code being sequentially transmitted on the specified sub-carriers and other sub-carriers.

14. The LDPC coded, IEEE 802.11 compatible MIMO broadcast system of claim 11 , wherein the specified sub-carriers are transmitted by a first transmission antenna and other sub-carriers are transmitted by at least one other antenna.

15. The LDPC coded, IEEE 802.11 compatible MIMO broadcast system of claim 9 , wherein the base LDPC code is 192 bits long.

16. The LDPC coded, IEEE 802.11 compatible MIMO broadcast system of claim 9 , wherein the encoder is further configured to use a longer LDPC code instead of the base LDPC code, wherein a length of the longer LDPC code is an integer multiple of the base LDPC code.

17. The LDPC coded, IEEE 802.11 compatible MIMO broadcast system of claim 16 , further comprising bits of the longer LDPC code being sequentially transmitted on the specified sub-carriers and other sub-carriers.

18. The LDPC coded, IEEE 802.11 compatible MIMO broadcast system of claim 9 , wherein the specified sub-carriers are transmitted by a first transmission antenna and other sub-carriers are transmitted by at least one other antenna.

19. A method for implementing Low Density Parity Check (LDPC) codes in an IEEE 802.11 standard system configured to operate in a Multiple-Input, Multiple-Output schema, and encoding an input information stream with the LDPC codes, comprising:

a) defining a base LDPC code, having a length equal to an integer multiple of a number of data carriers in an Orthogonal Frequency Division Multiplexing (OFDM) symbol;

b) transmitting the base LDPC code in place of a space-time code over a first plurality of sub-carriers, and

c) transmitting the base LDPC code in place of the space-time code on a second plurality of sub-carriers that are different from the first plurality of sub-carriers, wherein the base LDPC code on the second plurality of sub-carriers is transmitted offset in phase from the base LDPC code transmitted on the first plurality of sub-carriers.

20. The method of claim 19 , wherein the base LDPC code is 192 bits long.

21. The method of claim 19 , further comprising using a longer LDPC code instead of the base LDPC code, wherein a length of the longer LDPC code is an integer multiple of the base LDPC code.

22. The method of claim 21 , further comprising transmitting bits of the longer LDPC code sequentially on the first plurality of sub-carriers and the second plurality of sub-carriers.

23. The method of claim 19 , wherein the first plurality of sub-carriers are transmitted by a first transmission antenna and the second plurality of sub-carriers are transmitted by at least one other antenna.

24. A Low Density Parity Check coded, IEEE 802.11 compatible Multiple-Input, Multiple-Output (MIMO) broadcast system, comprising:

an encoder to receive a base LDPC code having a length equal to an integer multiple of a number of data carriers in an OFDM symbol instead of a space-time code, and to encode information bits using the LDPC code;

a modulator, coupled to the encoder, to modulate the encoded information bits;

a transmitter, coupled to the modulator, to transmit the modulated encoded information bits on a plurality of transmit antennas, wherein the modulated encoded information bits are transmitted on a first plurality of sub-carriers.

25. The LDPC coded, IEEE 802.11 compatible MIMO broadcast system of claim 24 , further comprising:

a plurality of receive antennas to receive the transmitted modulated encoded information bits;

a detector, coupled to the antennas, to detect the presence of the transmitted modulated encoded information bits;

an LDPC decoder, coupled to the detector, to decode the transmitted modulated encoded information bits; and

a demodulator, coupled to the LDPC decoder, to demodulate the transmitted modulated encoded information bits.

26. The LDPC coded, IEEE 802.11 compatible MIMO broadcast system of claim 24 , wherein the base LDPC code is 192 bits long.

27. The LDPC coded, IEEE 802.11 compatible MIMO broadcast system of claim 24 , further comprising using a longer LDPC code instead of the base LDPC code, wherein a length of the longer LDPC code is an integer multiple of the base LDPC code.

28. The LDPC coded, IEEE 802.11 compatible MIMO broadcast system of claim 27 , further comprising bits of the longer LDPC code being sequentially transmitted on the first plurality of sub-carriers and a second plurality of sub-carriers that are different from the first plurality of sub-carriers.

29. The LDPC coded, IEEE 802.11 compatible MIMO broadcast system of claim 24 , wherein the first plurality of sub-carriers are transmitted by a first transmission antenna and the second plurality of sub-carriers are transmitted by at least one other antenna.

Assignments (6)