TRANSMISSION DEVICE, RECEIVING DEVICE, TRANSMISSION METHOD, AND RECEIVING METHOD

• US 20150043466A1
• Filed: 03/08/2013
• Published: 02/12/2015
• Est. Priority Date: 03/19/2012
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Inventors: Yoshida, Tadashi, Horiuchi, Ayako, Iwai, Takashi, Ogawa, Yoshihiko, Nishio, Akihiko
• Granted Patent: US 11,005,543 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04B 7/0456 Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
• CPC Class Codes: H04B 7/0632 Channel quality parameters, e.g. channel quality indicator [CQI]
• CPC Class Codes: H04B 7/068 using space frequency diversity space-frequency coding H04L1/0606
• CPC Class Codes: H04B 7/0689 using different transmission schemes, at least one of them being a diversity transmission scheme
• CPC Class Codes: H04B 7/0691 using subgroups of transmit antennas
• CPC Class Codes: H04B 7/0871 using different reception schemes, at least one of them being a diversity reception scheme
• CPC Class Codes: H04B 7/0874 using subgroups of receive antennas
• CPC Class Codes: H04J 11/00 Orthogonal multiplex systems, e.g. using WALSH codesH04J13/00 takes precedence
• CPC Class Codes: H04J 13/00 Code division multiplex systems for frequency hopping H04B1/713
• CPC Class Codes: H04J 13/0003 Code application, i.e. aspects relating to how codes are applied to form multiplexed channels
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0051 of dedicated pilots, i.e. pilots destined for a single user or terminal
• CPC Class Codes: H04W 72/04 Wireless resource allocation

Abstract

This invention is a transmission device capable of enhancing the reception characteristics of a terminal when employing transmit diversity using two antenna ports in an ePDCCH. In a base station (100) that transmits a reference signal to a terminal (200) using two antenna ports, a setting unit (102), on the basis of the reception quality of the terminal, sets as the aforementioned two antenna ports either a first antenna port pair for which DMRS (reference signals) do not undergo mutual code multiplexing, or a second antenna port pair for which the DMRS do undergo code multiplexing. A transmitter (109) transmits the DMRS from the two antenna ports set in the setting unit (102).

Claims

1. A transmission apparatus that transmits reference signals to a reception apparatus using two antenna ports, the transmission apparatus comprising:

a configuration section that configures one of a first antenna port pair and a second antenna port pair as the two antenna ports based on reception quality of the reception apparatus, the first antenna port pair being an antenna port pair in which the reference signals are not mutually code-multiplexed, the second antenna port pair being an antenna port pair in which the reference signals are code-multiplexed; and

a transmission section that transmits the reference signals from the two configured antenna ports.

2. The transmission apparatus according to claim 1, wherein the configuration section configures the first antenna port pair when an aggregation level configured in the reception apparatus is equal to or greater than a threshold and configures the second antenna port pair when the aggregation level is less than the threshold.

3. The transmission apparatus according to claim 1, wherein:

the reception quality is more favorable when a higher CQI value is reported from the reception apparatus; and

the configuration section configures the first antenna port pair when the CQI value is less than a threshold and configures the second antenna port pair when the CQI value is equal to or greater than the threshold.

4. The transmission apparatus according to claim 1, wherein the configuration section configures the first antenna port pair when a number of control channel elements used for the reception apparatus among a plurality of control channel elements forming one physical channel resource block is equal to or greater than a threshold, and configures the second antenna port pair when the number of the control channel elements is less than the threshold.

5. The transmission apparatus according to claim 1, wherein the configuration section configures the first antenna port pair when a second subframe is configured in the reception apparatus and configures the second antenna port pair when a first subframe is configured in the reception apparatus, the second subframe being a subframe for which transmission power of a signal from the transmission apparatus is configured to be lower than that for the first subframe.

6. The transmission apparatus according to claim 1, wherein:

one of the first antenna port pair and the second antenna port pair is associated with each of a plurality of resources allocatable to the reception apparatus; and

the configuration section configures one of the first antenna port pair and the second antenna port pair as the two antenna ports, the one of the first and the second antenna port pairs being associated with a resource allocated based on the reception quality of the reception apparatus.

7. The transmission apparatus according to claim 1, wherein:

the first antenna port pair or the second antenna port pair is associated with each of a plurality of component carriers allocatable to the reception apparatus; and

the configuration section configures one of the first antenna port pair and the second antenna port pair as the two antenna ports, the one of the first and the second antenna ports being associated with a component carrier allocated based on the reception quality of the reception apparatus.

8. The transmission apparatus according to claim 7, wherein the first antenna port pair is associated with a component carrier that does not transmit at least one of PDCCH (physical downlink control channel) and CRS (cell specific reference signal) among the plurality of component carriers allocatable to the reception apparatus, and the second antenna port pair is associated with a component carrier that transmits the PDCCH and the CRS among the plurality of component carriers.

9. The transmission apparatus according to claim 1, wherein the configuration section configures the first antenna port pair when the reception apparatus is configured with a first allocation method that allocates signals in a distributed manner in a frequency domain and configures the second antenna port pair when the reception apparatus is configured with a second allocation method that allocates signals in a localized manner in a frequency domain.

10. The transmission apparatus according to claim 1, wherein, when configuring the reception apparatus with the second antenna port pair, the configuration section configures an antenna port other than antenna ports included in the two antenna ports pairs, as an antenna port to be used for transmission of a signal intended for a reception apparatus configured with a transmission method using a single-antenna port.

11. A reception apparatus comprising:

a reception section that receives reference signals transmitted using two antenna ports among a plurality of antenna ports included in a transmission apparatus; and

a control signal processing section that identifies one of a first antenna port pair and a second antenna port pair as the two antenna ports based on reception quality of the reception apparatus and that demodulates a control signal using reference signals in the identified two antenna ports, the first antenna port pair being an antenna port pair in which the reference signals are not mutually code-multiplexed, the second antenna port pair being an antenna port pair in which the reference signals are code-multiplexed.

12. A transmission method for transmitting reference signals to a reception apparatus using two antenna ports, the transmission method comprising:

configuring one of a first antenna port pair and a second antenna port pair as the two antenna ports based on reception quality of the reception apparatus, the first antenna port pair being an antenna port pair in which the reference signals are not mutually code-multiplexed, the second antenna port pair being an antenna port pair in which the reference signals are code-multiplexed; and

transmitting the reference signals from the two configured antenna ports.

13. A reception method comprising:

receiving reference signals transmitted using two antenna ports among a plurality of antenna ports included in a transmission apparatus; and

identifying one of a first antenna port pair and a second antenna port pair as the two antenna ports based on reception quality of a reception apparatus and demodulating a control signal using reference signals in the identified two antenna ports, the first antenna port pair being an antenna port pair in which the reference signals are not mutually code-multiplexed, the second antenna port pair being an antenna port pair in which the reference signals are code-multiplexed.