TRANSMISSION APPARATUS AND COMMUNICATION METHOD

• US 20090268838A1
• Filed: 06/13/2007
• Published: 10/29/2009
• Est. Priority Date: 06/19/2006
• Status: Abandoned Application

• Current Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Original Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Inventors: Miki, Nobuhiko, Sawahashi, Mamoru, Higuchi, Kenichi
• Application Number:
  US12/304,439
• Publication Number:
  US 20090268838A1
• Time in Patent Office: Days
• US Class Current: 375/267
• CPC Class Codes: H04B 1/7143 Arrangements for generation of hop patterns
• CPC Class Codes: H04B 7/086 using weights depending on external parameters, e.g. direction of arrival [DOA], predetermined weights or beamforming
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0046 Determination of how many bits are transmitted on different sub-channels
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: H04L 5/0091 Signaling for the administration of the divided path
• CPC Class Codes: H04W 52/04 TPC
• CPC Class Codes: H04W 52/24 using SIR [Signal to Interference Ratio] or other wireless path parameters
• CPC Class Codes: H04W 52/241 taking into account channel quality metrics, e.g. SIR, SNR, CIR, Eb/lo
• CPC Class Codes: H04W 52/325 Power control of control or pilot channels

Abstract

A transmission apparatus which multiplexes control channels for multiple reception apparatuses into an OFDM symbol at the same timing in OFDM downlink radio access includes a pattern generating unit configured to generate a frequency mapping pattern which is specific to the transmission apparatus; and a frequency allocating unit configured to allocate subcarriers to the control channels for the multiple reception apparatuses according to the frequency mapping pattern.

Claims

1. A transmission apparatus which multiplexes control channels for multiple reception apparatuses into an OFDM symbol at the same timing in OFDM downlink radio access, comprising:

a pattern generating unit configured to generate a frequency mapping pattern which is specific to the transmission apparatus; and

a frequency allocating unit configured to allocate subcarriers to the control channels for the multiple reception apparatuses according to the frequency mapping pattern.

2. The transmission apparatus as claimed in claim 1, further comprising:

a power control unit configured to control transmission power based on average reception quality on a system bandwidth for one of the reception apparatuses.

3. The transmission apparatus as claimed in claim 1, further comprising:

a power control unit configured to control transmission power for each subcarrier based on reception quality on a corresponding subcarrier at one of the reception apparatuses.

4. The transmission apparatus as claimed in claim 1, further comprising:

a power control unit configured to group the subcarriers into a predetermined number of subcarrier groups based on reception quality on a subcarrier allocated to one of the reception apparatuses and control transmission power for each subcarrier group.

5. The transmission apparatus as claimed in claim 1, further comprising:

a code multiplying unit configured to multiply the control channels for the multiple reception apparatuses with orthogonal codes to achieve orthogonalization among the multiple reception apparatuses;

wherein

the frequency allocating unit allocates the subcarriers to the control channels multiplied with the orthogonal codes according to the frequency mapping pattern.

6. The transmission apparatus as claimed in claim 1, wherein:

the frequency mapping pattern is transmitted to the multiple reception apparatuses on a broadcast channel.

7. The transmission apparatus as claimed in claim 5, wherein:

the orthogonal codes are transmitted to the multiple reception apparatuses on a broadcast channel.

8. The transmission apparatus as claimed in claim 1, wherein:

the transmission apparatus is a base station covering multiple sectors; and

the frequency allocating unit distinguishes subcarriers used for control channels in each of the sectors.

9. The transmission apparatus as claimed in claim 5, wherein:

the transmission apparatus is a base station covering multiple sectors; and

the code multiplying unit multiplies the control channels with orthogonal codes which are mutually different in each of the sectors.

10. A communication method in which a transmission apparatus multiplexes control channels for multiple reception apparatuses into an OFDM symbol at the same timing in OFDM downlink radio access, comprising the steps of:

generating a frequency mapping pattern which is specific to the transmission apparatus;

allocating the control channels for the multiple reception apparatuses to subcarriers according to the frequency mapping pattern; and

controlling transmission power for the subcarriers.