Radio reception apparatus, radio transmission apparatus, and radio communication method

• US 9,867,181 B2
• Filed: 09/14/2016
• Issued: 01/09/2018
• Est. Priority Date: 03/16/2009
• Status: Active Grant

• Current Assignee: Sun Patent Trust
• Original Assignee: Sun Patent Trust
• Inventors: Hoshino, Masayuki, Nishio, Akihiko, Nakao, Seigo, Imamura, Daichi
• Primary Examiner(s): Sheikh, Ayaz
• Assistant Examiner(s): VIDAL CARPIO, MARIELA
• Application Number:
  US15/264,940
• Publication Number:
  US 20170006592A1
• Time in Patent Office: 482 Days
• Field of Search: None
• CPC Class Codes: H04B 7/0486 taking channel rank into account
• CPC Class Codes: H04B 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04B 7/0632 Channel quality parameters, e.g. channel quality indicator [CQI]
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/06 using space diversity
• CPC Class Codes: H04L 1/1829 Arrangements specially adapted for the receiver end
• CPC Class Codes: H04L 1/20 using signal quality detector
• CPC Class Codes: H04L 25/0224 using sounding signals
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0051 of dedicated pilots, i.e. pilots destined for a single user or terminal
• 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 5/0073 Allocation arrangements that take into account other cell interferences for intercell interference mitigation or co-ordination in orthogonal multiplex systems H04J11/005
• CPC Class Codes: H04L 5/0082 at predetermined intervals
• CPC Class Codes: H04L 5/0094 Indication of how sub-channels of the path are allocated
• CPC Class Codes: H04W 72/044 based on the type of the allocated resource
• CPC Class Codes: H04W 72/1215 for collaboration of different radio technologies
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management

Abstract

Where first and second reference signals for a first and second communication system, respectively, are transmitted, resources that affect a reception apparatus compatible only with the first communication system can be minimized, and the throughput can be prevented from being deteriorated. As resources for a reference signal CSI-RS for LTE-A, last half symbols in a time direction of a resource unit RB/Sub-frame defined in a frequency-time domain are used, and the CSI-RS is allocated in a position up to the last two symbols or in the last symbol, or the like, of a particular RB/Sub-frame and transmitted when a reference signal 4RS for LTE is transmitted to a reception apparatus in addition to transmitting CSI-RS for LTE-A. The reception apparatus receives CSI-RS allocated in the last half symbol of RB/Sub-frame based on CSI-RS allocation information, measures channel quality by using this CSI-RS, and transmits and reports feedback information.

Claims

1. A receiving apparatus comprising:

a receiver, which, in operation, receives;

a first reference signal mapped in symbols of both a former half and a latter half of a subframe according to a time direction;

a second reference signal mapped to only last two symbols in the latter half of the subframe; and

data that is mapped in a given symbol in a frequency direction and then mapped in a symbol, which is next to the given symbol in a time direction, in the frequency direction, the data being comprised of systematic bits first followed by parity bits; and

circuitry, which, in operation, calculates channel quality using at least the second reference signal, and demodulates the received data,

wherein the first reference signal is a long-term evolution (LTE) reference signal in an LTE communication system, and the second reference signal is an LTE-Advanced reference signal in an LTE-Advanced communication system.

2. The receiving apparatus according to claim 1, wherein the second reference signal is mapped in a given subframe of a plurality of subframes, and the first reference signal is mapped in all of the plurality of subframes.

3. The receiving apparatus according to claim 1, wherein the second reference signal is not received in a subframe where a transmission of the second reference signal collides with a transmission of PBCH or SIB1.

4. The receiving apparatus according to claim 1, wherein the receiver, in operation, receives information related to a mapping of the second reference signal.

5. The receiving apparatus according to claim 4, wherein the information indicates a subframe where the second reference signal is mapped.

6. The receiving apparatus according to claim 1, wherein the second reference signal is cell-specific.

7. The receiving apparatus according to claim 1, wherein the second reference signal is used for calculating at least one of CQI, PMI and RI.

8. The receiving apparatus according to claim 1, wherein the second reference signal is a CSI-RS.

9. The receiving apparatus according to claim 1, wherein a number of antenna ports in the LTE-Advanced communication system is greater than a number of antenna ports in the LTE communication system.

10. A receiving method comprising:

receiving;

a first reference signal mapped in symbols of both a former half and a latter half of a subframe according to a time direction;

a second reference signal mapped to only last two symbols in the latter half of the subframe; and

data that is mapped in a given symbol in a frequency direction and then mapped in a symbol, which is next to the given symbol in a time direction, in the frequency direction, the data being comprised of systematic bits first followed by parity bits;

calculating channel quality using at least the second reference signal; and

demodulating the received data,

wherein the first reference signal is a long-term evolution (LTE) reference signal in an LTE communication system, and the second reference signal is an LTE-Advanced reference signal in an LTE-Advanced communication system.