Radio communication device and method of controlling transmission rate

• US 6,597,894 B1
• Filed: 08/28/2000
• Issued: 07/22/2003
• Est. Priority Date: 04/17/1998
• Status: Expired due to Term

• Current Assignee: INVT SPE LLC (SoftBank Group Corp.)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Hiramatsu, Katsuhiko, Kato, Osamu, Ue, Toyoki
• Primary Examiner(s): Hunter, Daniel
• Assistant Examiner(s): Gantt, Alan T.
• Application Number:
  US09/649,006
• Time in Patent Office: 1,058 Days
• Field of Search: 455/69, 455/67.1, 455/67.4, 455/63, 455/422, 370/465, 370/468
• US Class Current: 455/69
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 28/22 Negotiating communication rate
• CPC Class Codes: H04W 52/24 using SIR [Signal to Interference Ratio] or other wireless path parameters
• CPC Class Codes: H04W 52/265 taking into account the quality of service QoS
• CPC Class Codes: H04W 52/267 taking into account the information rate
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/542 using measured or perceived quality

Abstract

The communication terminal apparatus measures reception quality and reports the measurement result to the base station apparatus, and the base station apparatus switches the transmission rate based on the reported result of the reception quality. In this way, the transmission rate is switched starting at the point in time at which the reception quality of the communication terminal apparatus deteriorates. Furthermore, the transmission rate is switched so that the amount of interference with others is within the allowable range according to the channel condition between the communication terminal apparatus and base station apparatus.

Claims

1. A base station communication apparatus comprising:

transmission power control means for increasing or decreasing transmission power according to transmission power control information received from a communication terminal apparatus;

average transmission power calculating means for calculating an average value of the transmission power of a transmitting means;

allowable transmission power holding means for holding a predetermined allowable transmission power value;

comparing means for comparing the average value of transmission power with the allowable transmission power value; and

transmission rate control means for determining an initial transmission rate by negotiation with control means lying in a higher layer before starting communications, while changing a transmission rate based on the comparison result in said comparing means during the communications.

2. The base station communication apparatus according to claim 1, wherein said transmission rate control means controls a change in the transmission rate based on a transmission rate selected from a set of rates designated in advance from the higher layer.

3. The base station communication apparatus according to claim 1, wherein said transmission rate control means changes a spreading factor to change the transmission rate.

4. The base station communication apparatus according to claim 1, wherein said transmission rate control means decreases the transmission rate when the comparison result in said comparing means is indicative that the average value of transmission power reaches the allowable transmission power value.

5. A base station communication apparatus comprising:

transmission power control circuitry that increases or decreases transmission power according to transmission power control information received from a communication terminal apparatus;

average transmission power calculating circuitry that calculates an average value of the transmission power of a transmitter;

allowable transmission power holding circuitry that holds a predetermined allowable transmission power value;

comparison circuitry that compares the average value of transmission power with the allowable transmission power value; and

transmission rate control circuitry that determines an initial transmission rate by negotiation with a controller lying in a higher layer before starting communications, while changing a transmission rate based on the comparison result in said comparison circuitry during the communications.

6. The base station communication apparatus according to claim 5, wherein said transmission rate control circuitry controls a change in the transmission rate based on a transmission rate selected from a set of rates designated in advance from the higher layer.

7. The base station communication apparatus according to claim 5, wherein said transmission rate control circuitry changes a spreading factor to change the transmission rate.

8. The base station communication apparatus according to claim 5, wherein said transmission rate control circuitry decreases the transmission rate when the comparison result in said comparison circuitry is indicative that the average value of transmission power reaches the allowable transmission power value.

9. A variable transmission rate control method comprising the steps of:

determining an initial transmission rate by negotiation with control means lying in a higher layer before starting communications;

comparing an average value of transmission power over at least one frame with a threshold indicative of predetermined allowable transmission power; and

variably controlling the transmission rate based on the comparison result during the communications.