Multi-carrier transmitting apparatus and multi-carrier transmitting method

• US 20060160498A1
• Filed: 10/01/2003
• Published: 07/20/2006
• Est. Priority Date: 10/10/2002
• Status: Active Grant

• Current Assignee: Optis Wireless Technology, LLC (Brevet Capital)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Sudo, Hiroaki
• Granted Patent: US 7,529,315 B2
• Time in Patent Office: Days
• US Class Current: 455/103
• CPC Class Codes: H03M 13/2957 Turbo codes and decoding
• CPC Class Codes: H03M 13/37 Decoding methods or techniques, not specific to the particular type of coding provided for in groups H03M13/03 - H03M13/35
• CPC Class Codes: H03M 13/6325 Error control coding in combination with demodulation
• CPC Class Codes: H04L 1/0041 Arrangements at the transmitter end
• CPC Class Codes: H04L 1/006 Trellis-coded modulation
• CPC Class Codes: H04L 1/0066 Parallel concatenated codes
• CPC Class Codes: H04L 1/0071 Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 2001/0098 Unequal error protection
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0021 in which codes are applied as a frequency-domain sequences, e.g. MC-CDMA
• CPC Class Codes: H04L 5/0037 Inter-user or inter-terminal allocation
• CPC Class Codes: H04L 5/0042 intra-user or intra-terminal allocation
• CPC Class Codes: H04L 5/0046 Determination of how many bits are transmitted on different sub-channels
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: H04L 5/0064 Rate requirement of the data, e.g. scalable bandwidth, data priority

Abstract

A coding section 101 turbo-codes transmit data and outputs parity bit data, and systematic bit data for which good quality is required. A modulation section 102 modulates the parity bit data and systematic bit data. A subcarrier allocation section 103 rearranges the transmit data so that systematic bit data is allocated to subcarriers in the vicinity of the center frequency and parity bit data is allocated to subcarriers in the vicinity of both ends. An OFDM section 104 performs orthogonal frequency division multiplexing of the transmit data, and allocates parity bit data and systematic bit data to respective subcarriers. By this means, it is possible to improve significantly the error rate characteristics of transmit data for which good quality is required, and prevent degradation of the quality of transmit data for which good quality is required.

Claims

1. A multicarrier transmitting apparatus comprising:

a dividing section that divides transmit data into high-quality transmit data for which good quality is required and ordinary transmit data other than said high-quality transmit data;

a rearranging section that rearranges said transmit data so that said high-quality transmit data is allocated to a subcarrier in the vicinity of a center frequency; and

an orthogonal frequency division multiplexing section that performs orthogonal frequency division multiplexing of said transmit data rearranged by said rearranging section and allocates said transmit data to subcarriers.

2. The multicarrier transmitting apparatus according to claim 1, further comprising a spreading section that performs spreading processing of said transmit data rearranged by said rearranging section, wherein said orthogonal frequency division multiplexing section performs orthogonal frequency division multiplexing of said transmit data that has undergone spreading processing and allocates said transmit data to subcarriers.

3. The multicarrier transmitting apparatus according to claim 2, wherein said spreading section independently sets spreading ratios of said high-quality transmit data and said ordinary transmit data.

4. The multicarrier transmitting apparatus according to claim 2, wherein said spreading section makes a spreading ratio of said high-quality transmit data greater than a spreading ratio of said ordinary transmit data.

5. The multicarrier transmitting apparatus according to claim 2, wherein code multiplexing numbers of said high-quality transmit data and said ordinary transmit data are set independently.

6. The multicarrier transmitting apparatus according to claim 2, wherein a code multiplexing number of said high-quality transmit data is made smaller than a code multiplexing number of said ordinary transmit data.

7. The multicarrier transmitting apparatus according to claim 2, wherein numbers of spreading codes assigned to said high-quality transmit data and said ordinary transmit data are set independently.

8. The multicarrier transmitting apparatus according to claim 2, wherein a number of spreading codes assigned to said high-quality transmit data is made greater than a number of spreading codes assigned to said ordinary transmit data.

9. The multicarrier transmitting apparatus according to claim 1, further comprising a modulation section that modulates said high-quality transmit data and said ordinary transmit data using independently set modulation methods.

10. The multicarrier transmitting apparatus according to claim 9, wherein said modulation section fixes a modulation method of either said high-quality transmit data or said ordinary transmit data, and adaptively changes a modulation method of the other of said high-quality transmit data or said ordinary transmit data.

11. The multicarrier transmitting apparatus according to claim 9, wherein said modulation section adaptively changes a modulation method of both said high-quality transmit data and said ordinary transmit data.

12. The multicarrier transmitting apparatus according to claim 9, wherein said modulation section selects a modulation method in accordance with an adjacent channel interference wave reception level.

13. The multicarrier transmitting apparatus according to claim 1, further comprising an interleaving section that independently interleaves said high-quality transmit data and said ordinary transmit data, wherein said rearranging section rearranges said transmit data after interleaving.

14. The multicarrier transmitting apparatus according to claim 1, wherein said rearranging section rearranges said transmit data so that said ordinary transmit data is allocated to a subcarrier containing a DC point.

15. The multicarrier transmitting apparatus according to claim 1, further comprising a transmission power setting section that sets transmission power of said high-quality transmit data higher than transmission power of said ordinary transmit data.

16. The multicarrier transmitting apparatus according to claim 15, wherein said transmission power setting section sets transmission power of said high-quality transmit data and said ordinary transmit data variably.

17. The multicarrier transmitting apparatus according to claim 15, wherein said transmission power setting section sets transmission power of either said high-quality transmit data or said ordinary transmit data variably.

18. The multicarrier transmitting apparatus according to claim 15, wherein said transmission power setting section varies transmission power in accordance with channel quality.

19. The multicarrier transmitting apparatus according to claim 1, wherein said orthogonal frequency division multiplexing section narrows a range of subcarriers to which said high-quality transmit data is allocated when an adjacent channel interference wave reception level increases.

20. The multicarrier transmitting apparatus according to claim 1, further comprising a coding section that turbo-codes said transmit data, wherein said high-quality transmit data is systematic bit data and said ordinary transmit data is parity bit data.

21. The multicarrier transmitting apparatus according to claim 1, wherein said high-quality transmit data is transmit data that is transmitted to a distant communicating party, and said ordinary transmit data is transmit data that is transmitted to a nearby communicating party.

22. The multicarrier transmitting apparatus according to claim 1, wherein said high-quality transmit data is information used for communication control or retransmission information.

23. The multicarrier transmitting apparatus according to claim 1, further comprising a selection section that selects said ordinary transmit data so that subcarriers to which part of said ordinary transmit data rearranged by said rearranging section and said high-quality transmit data are allocated are transmitted.

24. The multicarrier transmitting apparatus according to claim 1, wherein said selection section selects said ordinary transmit data so that a number of subcarriers to which said ordinary transmit data is allocated that are transmitted is variable.

25. The multicarrier transmitting apparatus according to claim 1, wherein said selection section selects said ordinary transmit data so that a number of subcarriers to which said ordinary transmit data is allocated that are transmitted is variable according to channel quality.

26. The multicarrier transmitting apparatus according to claim 1, wherein said selection section selects said ordinary transmit data so that a number of subcarriers to which said ordinary transmit data is allocated that are transmitted is variable based on delay distribution information of said transmit data.

27. The multicarrier transmitting apparatus according to claim 1, wherein said selection section selects said ordinary transmit data that is allocated to subcarriers of a predetermined reception level or higher.

28. The multicarrier transmitting apparatus according to claim 1, wherein said selection section selects so that a number of subcarriers to which said ordinary transmit data is allocated that are transmitted is variable in accordance with an adjacent channel interference wave reception level.

29. A base station apparatus that has a multicarrier transmitting apparatus comprising:

a dividing section that divides transmit data into high-quality transmit data for which good quality is required and ordinary transmit data other than said high-quality transmit data;

a rearranging section that rearranges said transmit data so that said high-quality transmit data is allocated to a subcarrier in the vicinity of a center frequency; and

an orthogonal frequency division multiplexing section that performs orthogonal frequency division multiplexing of said transmit data rearranged by said rearranging section and allocates said transmit data to subcarriers.

30. A communication terminal apparatus that has a multicarrier transmitting apparatus comprising:

a dividing section that divides transmit data into high-quality transmit data for which good quality is required and ordinary transmit data other than said high-quality transmit data;

a rearranging section that rearranges said transmit data so that said high-quality transmit data is allocated to a subcarrier in the vicinity of a center frequency; and

an orthogonal frequency division multiplexing section that performs orthogonal frequency division multiplexing of said transmit data rearranged by said rearranging section and allocates said transmit data to subcarriers.

31. A multicarrier transmitting method comprising:

a step of dividing transmit data into high-quality transmit data for which good quality is required and ordinary transmit data other than said high-quality transmit data;

a step of rearranging said transmit data so that said high-quality transmit data is allocated to a subcarrier in the vicinity of a center frequency; and

a step of performing orthogonal frequency division multiplexing of rearranged said transmit data and allocating said transmit data to subcarriers.

32. The multicarrier transmitting method according to claim 31, further comprising a step of spreading said transmit data.

33. The multicarrier transmitting method according to claim 31, further comprising a step of modulating said high-quality transmit data and said ordinary transmit data using independently set modulation methods.

34. The multicarrier transmitting method according to claim 33, further comprising a step of selecting a modulation method in accordance with an adjacent channel interference wave reception level.

35. The multicarrier transmitting method according to claim 31, wherein said high-quality transmit data is transmit data that is transmitted to a distant communicating party, and said ordinary transmit data is transmit data that is transmitted to a nearby communicating party.

36. The multicarrier transmitting method according to claim 31, further comprising a step of independently interleaving said high-quality transmit data and said ordinary transmit data.

37. The multicarrier transmitting method according to claim 31, wherein said ordinary transmit data is selected so that subcarriers to which part of said ordinary transmit data rearranged by said rearranging section and said high-quality transmit data are allocated are transmitted.