Cdma transmitting apparatus and cdma receiving apparatus

• US 20060007892A1
• Filed: 11/14/2003
• Published: 01/12/2006
• Est. Priority Date: 11/14/2002
• Status: Active Grant

• Current Assignee: INVT SPE LLC (FIG LLC (d/b/a Fortress Investment Group LLC))
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Sudo, Hiroaki
• Granted Patent: US 7,693,140 B2
• Time in Patent Office: Days
• US Class Current: 370/335
• CPC Class Codes: H04B 2201/70703 using multiple or variable rates
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/18 Automatic repetition systems, e.g. Van Duuren systems

Abstract

An S/P converting section (101) converts input transmission signals A1, A2, B1, B2, . . . , K1, K2 to parallelized data, separated in individual transmission lines. Spreading sections (102, 103) spread the respective data under control of a spread control section (107). Adding sections (104-1, 104-2) multiplex spread data. Transmitting sections (105-1, 105-2) provide radio transmission processing to the multiplexed signals, and transmit the data via antennas (106-1, 106-2) by radio. The spread control section (107) controls the spreading methods in the spreading sections (102, 103) based on channel quality. This makes it possible to improve error rate characteristics of the received signal and as maintain spectrum efficiency when varying data is transmitted from multiple antennas.

Claims

1. A CDMA transmitting apparatus comprising:

first and second spreading sections that perform spreading for signals different from each other;

first and second transmitting sections that correspond to the first and second spreading sections respectively and transmit the spread signals by radio; and

a spreading method setting section that sets spreading methods in the first and second spreading sections independently.

2. The CDMA transmitting apparatus according to claim 1, wherein the spreading method setting section sets at least one of a spreading factor, the number of spreading codes, and the number of spreading codes assigned to one transmitting party, employed in the first spreading section, independent of the second spreading section.

3. The CDMA transmitting apparatus according to claim 1, wherein the spreading method setting section performs the setting based on at least one of a channel quality, a degree of importance, and the number of retransmissions, of each signal transmitted by radio from the first and second transmitting sections.

4. The CDMA transmitting apparatus according to claim 3, wherein the spreading method setting section sets in the first spreading section a spreading method that improves reception accuracy at a receiving side, in at least one of the following cases:

the channel quality of a signal transmitted by radio from the first transmitting section is poorer than the channel quality of a signal transmitted by radio from the second transmitting section;

the degree of importance of the signal transmitted by radio from the first transmitting section is greater than the degree of importance of the signal transmitted by radio from the second transmitting section; and

the number of retransmissions of the signal transmitted by radio from the first transmitting section is greater than the number of retransmissions of the signal transmitted by radio from the second transmitting section.

5. The CDMA transmitting apparatus according to claim 4, wherein the spreading method setting section sets the spreading factor used in the first spreading section greater than the spreading factor used in the second spreading section.

6. The CDMA transmitting apparatus according to claim 4, wherein the spreading method setting section sets the number of spreading codes actually used in the first spreading section smaller than the number of spreading codes actually used in the second spreading section.

7. The CDMA transmitting apparatus according to claim 4, wherein the spreading method setting section sets the number of spreading codes the first spreading section assigns to one transmitting party greater than the number of spreading codes the second spreading section assigns to one transmitting party.

8. The CDMA transmitting apparatus according to claim 4, wherein, when the degree of importance of the signal transmitted by radio from the first transmitting section is greater than the degree of importance of the signal transmitted by radio from the second transmitting section, the signal transmitted by radio from the first transmitting section comprises control information or retransmission information.

9. The CDMA transmitting apparatus according to claim 4, wherein the setting is performed for only a fixed period of time.

10. The CDMA transmitting apparatus according to claim 1, further comprising an assigning section that assigns to the first and second transmitting sections respective transmitting parties,

wherein the spreading method setting section sets in the second spreading section a spreading method that improves reception accuracy at a receiving side greater than by the first spreading section;

and

wherein the assigning section assigns the transmitting party having a greater number of retransmissions than a predetermined number to the first transmitting section.

11. The CDMA transmitting apparatus according to claim 4, wherein transmission power of the first transmitting section is set greater than transmission power of the second transmitting section.

12. The CDMA transmitting apparatus according to claim 7, wherein the spreading method setting section applies the setting to a transmitting party having a lower channel quality than a predetermined quality.

13. The CDMA transmitting apparatus according to claim 4, wherein, when error correction codes of the signals transmitted by radio from the first and second transmitting sections comprises a turbo code, the signal transmitted by radio from the first transmitting section comprises a systematic bit.

14. The CDMA transmitting apparatus according to claim 1, wherein the signals transmitted by radio from the first and second transmitting sections are converted in multicarrier form.

16. A communication terminal apparatus comprising the CDMA transmitting apparatus of claim 1.

17. A base station apparatus comprising the CDMA transmitting apparatus of claim 1.

15. A CDMA receiving apparatus comprising:

first and second receiving sections that receive by radio signals in which varying signals are multiplexed;

separating section that separates the radio received signals back to varying signals prior to multiplexing;

first and second despreading sections that correspond to the first and second receiving sections respectively and despread the separated signals,

wherein despreading methods in the first and second despreading sections are set independently based on channel quality, degree of importance, and the number of retransmissions of each signal received by radio.

18. A radio transmitting method comprising:

first and second spreading steps of performing spreading for signals different from each other;

first and second transmitting steps, corresponding to the first and second spreading steps, respectively, of transmitting the spread signals by radio; and

a spreading method setting step of setting spreading methods in the first and second spreading steps independently.

19. A radio transmitting system comprising:

first and second spreading sections that perform spreading for signals different from each other;

first and second transmitting sections that correspond to the first and second spreading sections respectively and transmit the spread signals by radio; and

a spreading method setting section that sets spreading methods in the first and second spreading sections independently.