Apparatus and method for controlling transmission power in a wireless communication system

• US 20050147125A1
• Filed: 10/27/2004
• Published: 07/07/2005
• Est. Priority Date: 10/27/2003
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd., Seoul National University Industry Foundation (Seoul National University)
• Original Assignee: Samsung Electronics Co. Ltd., Seoul National University Industry Foundation (Seoul National University)
• Inventors: Jang, Kyung-Hun, Hwang, Hyo-Sun, Kim, Young-Soo, Choi, Sung-Hyun
• Granted Patent: US 7,821,976 B2
• Time in Patent Office: Days
• US Class Current: 370/471
• CPC Class Codes: H04W 52/286 during data packet transmission, e.g. high speed packet access [HSPA]
• CPC Class Codes: H04W 52/367 Power values between minimum and maximum limits, e.g. dynamic range
• CPC Class Codes: H04W 52/50 at the moment of starting communication in a multiple access environment

Abstract

A method and system for controlling the transmission power of a terminal transmitting frames in a wireless communication system, the frames having a frame structure including a header field containing information related to a transmission rate and length of data transmitted in a frame and a data field having the data. The transmitting terminal transmits the header field to a receiving terminal at a maximum transmit power level available to the transmitting terminal so that second terminals other than the transmitting terminal and the receiving terminal within the wireless communication system can identify that resources are in use. The transmitting terminal transmits the data field at an optimum transmit power level great enough to allow the data field to reach the receiving terminal.

Claims

1. A method of controlling the transmission power of a terminal transmitting frames in a wireless communication system, said frames having a frame structure, the frame structure including a header field containing information related to the transmission rate and length of data transmitted in a frame, and including a data field containing the data, the method comprising the steps of:

transmitting the header field to a receiving terminal at a maximum transmission power level available to the transmitting terminal so that second terminals within the wireless communication system other than the transmitting terminal and the receiving terminal can determine which resources are in use; and

transmitting the data field at an optimum transmission power level great enough to allow the data field to reach the receiving terminal.

2. The method of claim 1, wherein the resources is a carrier on which the data is transmitted/received.

3. A method of controlling the transmission power of a terminal transmitting frames in a wireless communication system, said frames having a frame structure, the frame structure including a header field containing information related to the transmission rate and length of data transmitted in a frame, and including a data field containing the data, the method comprising the steps of:

determining if resources are in use while preparing the frame for transmission;

transmitting the header field to a receiving terminal at a maximum transmission power level available to the transmitting terminal, if the resources are not in use; and

transmitting the data field at an optimum transmission power level great enough to allow the data field to reach the receiving terminal.

4. The method of claim 3, wherein the step of determining if the resources are in use comprises the step of determining if second terminals other than the transmitting terminal within the wireless communication system is transmitting data at the time it is determined that the frame is to be transmitted.

5. The method of claim 4, wherein the step of determining if at least one of the second terminals is transmitting data, comprises the steps of:

detecting information related to a transmission rate and a frame length from a header field of a frame to be sent to at least one of the second terminals, the frame targeting at the one of the terminals being received at or before the time it is determined that the frame is to be transmitted from the terminal;

determining the transmission duration of data included in the frame to be sent to at least one of the second terminals using the transmission rate and length information; and

determining that at least one of the second terminals is transmitting data if the time it is determined that the frame is to be transmitted is within the transmission duration of the data in the frame to be sent to at least one of the second terminals, and

determining that at least one of the second terminals is not transmitting data if the time it is determined that the frame is to be transmitted is not within the transmission duration of the data in the frame to be sent to at least one of the second terminals.

6. The method of claim 3, wherein the resources is a carrier on which the data is transmitted/received.

7. A method of controlling the transmission power of a terminal transmitting frames in a wireless communication system, the frames having a PLCP (Physical Layer Convergence Protocol) PDU (Protocol Data Unit) frame structure, the PLCP PDU frame structure including a PLCP preamble field indicating the start of the PLCP PDU frame, a PLCP header field containing information related to a transmission rate and length of data transmitted in the PLCP PDU frame, and a data field having the data, the method comprising the steps of:

transmitting the PLCP preamble and header fields to a receiving terminal at a maximum transmit power level available to the transmitting terminal so that second terminals other than the transmitting terminal and the receiving terminal within the wireless communication system can recognize that resources are in use; and

transmitting the data field at an optimum transmit power level great enough to allow the data field to reach the receiving terminal.

8. The method of claim 7, wherein the resources is a carrier on which the data is transmitted/received.

9. A method of controlling the transmission power of a terminal transmitting frames in a wireless communication system, the frames having a PLCP (Physical Layer Convergence Protocol) PDU (Protocol Data Unit) frame structure, the PLCP PDU frame structure including a PLCP preamble field indicating the start of the PLCP PDU frame, a PLCP header field containing information related to a transmission rate and length of data transmitted in the PLCP PDU frame, and a data field having the data, the method comprising the steps of:

determining if resources are in use when the PLCP PDU frame is to be transmitted;

transmitting the PLCP preamble and header fields to a receiving terminal at a maximum transmit power level available to the transmitting terminal, if the resources are not in use; and

transmitting the data field at an optimum transmit power level great enough to allow the data field to reach the receiving terminal.

10. The method of claim 9, wherein the step of determining if resources are in use comprises the step of determining if second terminals other than the transmitting terminal within the wireless communication system is transmitting data at the time it is determined that the PLCP PDU frame is to be transmitted.

11. The method of claim 10, wherein the step of determining if at least one of the second terminals is transmitting data comprises the steps of:

detecting information related to the transmission rate and the length from the PLCP header field of a PLCP PDU frame to be transmitted to at least one of the second terminals, the PLCP PDU frame to be transmitted to at least one of the second terminals being received at or before the time it is determined that the PLCP PDU frame is to be transmitted from the terminal;

determining the transmission duration of data included in the PLCP PDU frame to be transmitted to at least one of the second terminals using the transmission rate and length information; and

determining that at least one of the second terminals is transmitting data if the time it is determined that the PLCP PDU frame is to be transmitted is within the transmission duration of the data in the PLCP PDU frame to be transmitted to at least one of the second terminals, and determining that the one of the terminals is not transmitting data if the time it is determined that the PLCP PDU frame is to be transmitted is not within the transmission duration of the data in the PLCP PDU frame to be transmitted to at least one of the second terminals.

12. The method of claim 9, wherein the resources is a carrier on which the data is transmitted/received.

13. A system for controlling the transmission power of a terminal transmitting frames in a wireless communication system, the frames having a frame structure, the frame structure including a header field containing information related to a transmission rate and length of data transmitted in a frame, and a data field having the data, the system comprising:

a transmitting terminal for transmitting the header field to a receiving terminal at a maximum transmission power level available to the transmitting terminal so that second terminals other than the transmitting terminal and the receiving terminal within the wireless communication system can identify that resources are in use, and transmitting the data field at an optimum transmit power level great enough to allow the data field to reach the receiving terminal,

wherein the receiving terminal receives the frame, determines the transmission duration of the data using the transmission rate and length information included in the header field of the frame, and discontinues transmission of a new frame during the determined data transmission duration.

14. The system of claim 13, wherein the resources is a carrier on which the data is transmitted/received.

15. A system for controlling the transmission power of a terminal transmitting frames in a wireless communication system, frames having a PLCP (Physical Layer Convergence Protocol) PDU (Protocol Data Unit) frame structure, the PLCP PDU frame structure including a PLCP preamble field indicating the start of the PLCP PDU frame, a PLCP header field containing information related to a transmission rate and length of data transmitted in the PLCP PDU frame, and a data field having the data, the system comprising:

a transmitting terminal for determining if resources are in use at the time when the PLCP PDU frame is to be transmitted, transmitting the PLCP preamble and header fields to a receiving terminal at a maximum transmit power level available to the transmitting terminal, if the resources are not in use, and transmitting the data field at an optimum transmit power level great enough to allow the data field to reach the receiving terminal,

wherein the receiving terminal receives the PLCP PDU frame, determines the transmission duration of the data using the transmission rate and length information included in the PLCP header field of the PLCP frame, and discontinues the transmission of a new frame during the determined data transmission duration.

16. The system of claim 15, wherein the resources is a carrier on which the data is transmitted/received.