Wireless communication system and transmission device

• US 20060153098A1
• Filed: 05/13/2005
• Published: 07/13/2006
• Est. Priority Date: 01/13/2005
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Ito, Akira, Shimizu, Masahiko
• Granted Patent: US 8,116,241 B2
• Time in Patent Office: Days
• US Class Current: 370/254
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04B 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04B 7/0628 Diversity capabilities

Abstract

The present invention relates to a wireless communication system to properly switch over a transmission method of radio signals corresponding to a configuration of a receiver. The wireless communication system according to the present invention includes a transmitting device having a plurality of antennas and capable of transmitting radio signals different from each other from these antennas, and a receiving device having at least one antenna and receiving the radio signals transmitted from the transmitting device. The receiving device comprises an information transmitting unit transmitting, to the transmitting device, configuration information about a configuration of the receiving device, and the transmitting device includes a transmitting unit transmitting the radio signals by a transmission method corresponding to the configuration information received from the receiving device.

Claims

1. A wireless communication system including a transmitting device having a plurality of antennas and transmitting different radio signals from each of the plurality of antennas, and a receiving device having at least one of antennas and receiving the radio signals transmitted from said transmitting device,

said receiving device comprising

an information transmitting unit transmitting, to said transmitting device, configuration information about a configuration of said receiving device, and

said transmitting device comprising

a transmitting unit transmitting the radio signals by a transmission method corresponding to the configuration information received from said receiving device.

2. A wireless communication system according to claim 1, wherein the configuration information contains information about the number of the antennas of said receiving device, and

said transmitting unit determines the transmission method based on the information about the number of the antennas contained in the configuration information.

3. A wireless communication system according to claim 2,

said receiving device further comprising

an extraction unit extracting, from the received radio signals, transmission characteristic information containing transmission path information corresponding to an environment where the radio signals are transmitted, wherein

said information transmitting unit transmits the configuration information and the transmission characteristic information,

said transmitting device further comprising

a detection unit detecting the transmission path information from the transmission characteristic information received from said receiving device and

a transforming unit transforming transmission signals based on the detected transmission path information and the information about the number of the antennas contained in the configuration information, wherein

said transmitting unit transmits the radio signals corresponding to the transformed transmission signals.

4. A wireless communication system according to claim 3, wherein said transforming unit transforms the transmission signals so that symbol data series of the radio signals received by one of the antennas of said receiving device become symbol data series of which the number is equal to or smaller than the number of symbol data series corresponding to the number of the antennas of said receiving device.

5. A wireless communication system according to claim 4, wherein the configuration information contains information indicating a demodulation method executed by said receiving device, and

said transforming unit transforms the transmission signals based on the transmission path information, the information about the number of the antennas and the information indicating the demodulation method so that said receiving device receives only the radio signals corresponding to the information about the number of the antennas and the demodulation method.

6. A wireless communication system according to claim 5, said transmitting device further comprising

a transmission rate control unit controlling a transmission rate of the transmission signals based on the configuration information and the transmission path information.

7. A wireless communication system according to claim 6, wherein the configuration information contains information indicating a data identifying method executed by said receiving device, and

said transmission rate control unit controlling the transmission rate of the transmission signals based on the configuration information, the transmission path information and the information indicating the data identifying method.

8. A transmitting device comprising:

a plurality of antennas;

an acquisition unit acquiring configuration information about a configuration of a receiving device receiving radio signals and transmission path information corresponding to an environment where the radio signals are transmitted;

a transforming unit transforming transmission signals based on the transmission path information and information about the number of the antennas of said receiving device that is contained in the configuration information; and

a transmitting unit transmitting, from the plurality of antennas, the radio signals corresponding to the transformed transmission signals by a transmission method corresponding to the configuration information.

9. A transmitting device according to claim 8,

wherein said transforming unit transforms the transmission signals so that the radio signals received by one of the antennas of said receiving device become symbol data series of which the number is equal to or smaller than the number of symbol data series corresponding to the number of antennas of said receiving device.

10. A transmitting device according to claim 9, further comprising

a transmission rate control unit controlling a transmission rate of the transmission signals based on the configuration information and the transmission path information.