RADIO COMMUNICATION METHOD, RADIO COMMUNICATION SYSTEM, AND RADIO COMMUNICATION DEVICE

• US 20090028262A1
• Filed: 07/29/2005
• Published: 01/29/2009
• Est. Priority Date: 08/04/2004
• Status: Abandoned Application

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Imai, Tomohiro, Imamura, Daichi, Yuda, Yasuaki
• Application Number:
  US11/573,028
• Publication Number:
  US 20090028262A1
• Time in Patent Office: Days
• US Class Current: 375/267
• CPC Class Codes: H04L 2209/34 Encoding or coding, e.g. Huffman coding or error correction
• CPC Class Codes: H04L 2209/80 Wireless
• CPC Class Codes: H04L 9/0875 based on channel impulse response [CIR]
• CPC Class Codes: H04W 12/041 Key generation or derivation

Abstract

There are disclosed a radio communication device and others capable of generating in a short time a secret key common to a base station and a mobile station in a radio communication system using the MIMO technique and starting the encrypted communication at an early stage. In this device, in ST545, when a channel coincidence judgment unit (105) and a channel coincidence judgment processing unit (205) respectively judge that the channel matrix generated by the base station completely coincides with the channel matrix generated by the mobile station or they do not coincide completely but they can coincide finally by error correction of the secret key or the like, according to the judgment result indicated in the channel coincidence judgment signal generated in ST540-2, ST545 is followed by ST550. On the other hand, when the channel matrix generated by the base station does not coincide completely with the channel matrix generated by the mobile station and they do not coincide finally even after error correction of the secret key, ST510 is again executed after ST545.

Claims

1. A wireless communication method for carrying out wireless communication using a first wireless communication apparatus comprising a plurality of first antennas and a second wireless communication apparatus comprising a plurality of second antennas, the wireless communication method comprising:

a first channel estimation step of calculating at the first wireless communication apparatus a first channel estimation value for a first MIMO channel formed between the plurality of first antennas and the plurality of second antennas;

a second channel estimation step of calculating at the second wireless communication apparatus a second channel estimation value for a second MIMO channel formed between the plurality of second antennas and the plurality of first antennas;

an information generation step of generating at the first wireless communication apparatus first channel information from the calculated first channel estimation value;

a channel matching determination step of determining at the second wireless communication apparatus whether or not the second MIMO channel and the first MIMO channel match based on the calculated second channel estimation value and the first channel information;

a first secret key generating step of generating at the first wireless communication apparatus a first secret key from the first channel estimation value only when it is determined in the channel matching determination step that the channels match; and

a second secret key generating step of generating at the second wireless communication apparatus a second secret key from the second channel estimation value only when it is determined in the channel matching determination step that the channels match.

2. The wireless communication method according to claim 1, wherein the first channel information in the information generation step is a correlation matrix of the first MIMO channel.

3. The wireless communication method according to claim 1, wherein:

in the first secret key generating step, the first wireless communication apparatus generates the first secret key from the first channel estimation value only when it is determined in the channel matching determination step that the channels match, and decides a number of bits for error correction in the generated first secret key; and

in the second secret key generating step, the second wireless communication apparatus generates the second secret key from the second channel estimation value only when it is determined in the channel matching determination step that the channels match, and decides a number of bits for error correction in the generated second secret key.

4. A wireless communication system provided with a first wireless communication apparatus comprising a plurality of first antennas and a second wireless communication apparatus comprising a plurality of second antennas, wherein:

the first wireless communication apparatus comprises;

a first channel estimation section that calculates a first channel estimation value for a first MIMO channel formed between the plurality of first antennas and the plurality of second antennas;

a correlation matrix generating section that generates a correlation matrix of the first MIMO channel from the calculated first channel estimation value; and

a first secret key generating section that generates a first secret key from the first channel estimation value only when it is determined that a second MIMO channel formed between the plurality of second antennas and the plurality of first antennas by the second wireless communication apparatus and the first MIMO channel match; and

the second wireless communication apparatus comprises;

a second channel estimation section that calculates a second channel estimation value for the second MIMO channel;

a matching determination processing section that determines whether or not the second MIMO channel and the first MIMO channel match based on the calculated second channel estimation value and the correlation matrix of the first MIMO channel; and

a second secret key generating section that generates a second secret key from the second channel estimation value only when it is determined by the matching determination processing section that the channels match.

5. A wireless communication apparatus comprising:

a plurality of first antennas that receive wireless signals of a first MIMO channel and transmit the wireless signals using a second MIMO channel;

a first channel estimation section that calculates a first channel estimation value from the received signals of the first MIMO channel;

a correlation matrix generating section that generates a correlation matrix of the first MIMO channel from the calculated first channel estimation value; and

a first secret key generating section that generates a first secret key from the first channel estimation value only when it is determined that the first MIMO channel and the second MIMO channel match based on the correlation matrix of the first MIMO channel.

6. The wireless communication apparatus according to claim 5, wherein:

the first secret key generating section generates the first secret key from the first channel estimation value only when it is determined that the first MIMO channel and the second MIMO channel match, and decides a number of bits for error correction in the generated first secret key; and

the wireless communication apparatus further comprises an error correction section that regards the number of bits for error correction decided by the first secret key generating section as an amount of redundant data and performs error correction on the first secret key.

7. A wireless communication apparatus comprising:

a plurality of second antennas that receive wireless signals of a second MIMO channel and transmit the wireless signals using a first MIMO channel;

a second channel estimation section that calculates a second channel estimation value from the received signals of the second MIMO channel;

a matching determination processing section that determines whether or not the second MIMO channel and the first MIMO channel match based on a correlation matrix of the first MIMO channel received by the second MIMO channel; and

a second secret key generating section that generates a second secret key from the second channel estimation value only when it is determined that the second MIMO channel and the first MIMO channel match.

8. The wireless communication apparatus according to claim 7, wherein:

the second secret key generating section generates the second secret key from the second channel estimation value only when it is determined that the second MIMO channel and the first MIMO channel match, and decides a number of bits for error correction in the generated second secret key; and

the wireless communication apparatus further comprises an error correction section that regards the number of bits for error correction decided by the second secret key generating section as an amount of redundant data and performs error correction on the second secret key.