Base station apparatus, communication terminal apparatus, and communication method

• US 20020155861A1
• Filed: 12/31/2001
• Published: 10/24/2002
• Est. Priority Date: 02/16/2000
• Status: Active Grant

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Shi, Guizeng, Aizawa, Junichi, Saito, Yoshiko, Uesugi, Mitsuru, Sumasu, Atsushi, Kato, Osamu, Ue, Toyoki, Uehara, Toshiyuki, Kitagawa, Keiichi
• Granted Patent: US 7,292,862 B2
• Time in Patent Office: Days
• US Class Current: 455/561
• CPC Class Codes: H04J 3/1682 Allocation of channels according to the instantaneous demands of the users, e.g. concentrated multiplexers, statistical multiplexers
• CPC Class Codes: H04L 5/026 using code division

Abstract

An assignment section 101 determines communication resource assignment to communication terminals based on a transmission rate at which communication is possible for each subcarrier of each communication terminal, and instructs a buffer section 102 to output forward transmission data. In addition, the assignment section 101 instructs a frame creation section 103 to perform forward transmission data symbolization, and also outputs a signal indicating communication resource assignment to each communication terminal. The buffer section 102 holds forward transmission data, and outputs forward transmission data to the frame creation section 103 in accordance with instructions from the assignment section 101. The frame creation section 103 symbolizes a resource assignment signal and transmission data to create a frame, which it outputs to a spreading section 104.

Claims

1. A base station apparatus comprising:

estimating means for estimating in each subcarrier a transmission rate in communication with a communication terminal apparatus;

assigning means for performing in each subcarrier assignment of communication resources to said communication terminal apparatus based on said transmission rate; and

creating means for creating a transmission symbol in accordance with instructions of this assignment means.

2. The base station apparatus according to claim 1, wherein said creating means symbolizes communication resource assignment information in each subcarrier.

3. The base station apparatus according to claim 1, further comprising spreading means for performing spreading by multiplying a transmission symbol by a spreading code in accordance with instructions of said assigning means.

4. The base station apparatus according to claim 1, wherein said assigning means performs communication resource assignment in each subcarrier and time units.

5. The base station apparatus according to claim 3, wherein said assigning means determines a spreading ratio based on a transmission rate estimated by said estimating means, and said spreading means spreads transmission symbols based on said spreading ratio.

6. A communication terminal apparatus comprising signal extracting means for extracting a signal addressed to the station itself in each subcarrier from a received signal.

7. The communication terminal apparatus according to claim 6, further comprising despreading means for despreading a received signal by multiplying it by a spreading code, wherein said signal extracting means extracts a signal addressed to the station itself from a received signal based on the quality of a despread received signal.

8. The communication terminal apparatus according to claim 7, wherein said signal extracting means performs threshold value determination for the quality of a despread received signal.

9. The communication terminal apparatus according to claim 6, further comprising:

control signal extracting means for extracting a control signal reporting communication resource assignment from a received signal; and

information extracting means for extracting assignment information addressed to that station itself from said control signal;

wherein said signal extracting means extracts a signal addressed to the station itself according to said assignment information.

10. A communication method whereby:

a base station apparatus estimates in each subcarrier a transmission rate in communication with a communication terminal apparatus, performs in each subcarrier assignment of communication resources to said communication terminal apparatus based on said transmission rate, and transmits assignment information and data created in accordance with this assignment to said communication terminal apparatus; and

said communication terminal apparatus extracts data addressed to that station in each subcarrier from said data in accordance with said assignment information.

11. A communication method whereby:

a base station apparatus estimates in each subcarrier a transmission rate in communication with a communication terminal apparatus, performs in each subcarrier assignment of communication resources to said communication terminal apparatus based on said transmission rate, and transmits data created in accordance with this assignment to said communication terminal apparatus; and

said communication terminal apparatus extracts data addressed to that station in each subcarrier from said data based on the quality of a despread received signal.