Mobile station employing selective discontinuous transmission for high speed data services in CDMA multi-channel reverse link configuration

• US 6,137,789 A
• Filed: 06/26/1997
• Issued: 10/24/2000
• Est. Priority Date: 06/26/1997
• Status: Expired due to Term

• Current Assignee: Callstat Solutions LLC (Jeffrey M. Gross)
• Original Assignee: Nokia Mobile Phones UK Limited (Nokia Corporation)
• Inventors: Honkasalo, Zhichun
• Primary Examiner(s): Vu, Huy D.
• Assistant Examiner(s): KWOH, JASPER C
• Application Number:
  US08/882,822
• Time in Patent Office: 1,216 Days
• Field of Search: 455/522, 455/69, 455/70, 455/450, 455/455, 375/200, 375/206, 375/287, 375/286, 370/465, 370/468, 370/332, 370/335, 370/342
• US Class Current: 370/342
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04L 2001/0096 Channel splitting in point-to-point links
• CPC Class Codes: H04W 52/267 taking into account the information rate
• CPC Class Codes: H04W 52/36 with a discrete range or set of values, e.g. step size, ramping or offsets
• CPC Class Codes: H04W 52/44 in connection with interruption of transmission

Abstract

This invention applies to a mobile station that is able to determine a required data rate based on data buffer usage. If the data buffer indicates a requirement for a high data rate transmission, the mobile station sends a request to a base station to be assigned multiple parallel code channels. If the multiple parallel code channels are granted, the mobile station uses the channels for transmitting data to the base station until either the data buffer becomes empty, or a base station time-out occurs, or the mobile station is signalled by the base station to reduce its data transmission rate, whichever occurs first. The mobile station of this invention is enabled to autonomously control the data rate during an assigned period for high speed transmission, so as to lower the data rate when needed for the purpose of improving coverage and/or to avoid operating in a power limited condition, thereby degrading link quality. The data rate is lowered by disabling transmission though at least one parallel code channel, and subsequently resuming transmission though the code channel when conditions warrant. This provides a discontinuous transmission (DTX) mode of operation for individual ones of supplemental parallel data code channels.

Claims

1. A method for operating a mobile station, comprising steps of:

establishing a wireless data communication from a transmitter of the mobile station to a receiver of the base station at a predetermined data rate simultaneously through a fundamental data channel and at least one supplemental data channel;

receiving a command from the base station to increase the transmission power of the mobile station transmitter;

determining in the mobile station if the increased transmission power will exceed a transmission power threshold value;

if so, reducing the data rate by disabling data transmission through the at least one supplemental data channel;

increasing the transmission power;

receiving a command from the base station to decrease the transmission power of the mobile station;

determining in the mobile station if the decreased transmission power, assuming that a disabled supplemental data channel were once more enabled, will be less than the transmission power threshold value;

if so, increasing the data rate by enabling data transmission through at least one previously disabled supplemental data channel; and

decreasing the transmission power.

2. A method as in claim 1, wherein the step of increasing the data rate includes a step of transmitting a message from the mobile station to the base station for indicating that transmission is being resumed through the at least one previously disabled supplemental data channel.

3. A method for operating a code division, multiple access (CDMA) mobile station, comprising the steps of:

requesting a base station for at least one data channel based at least in part on a desired mobile station data transmission rate;

receiving a distinct spreading code for each of said at least one data channel from the base station for use in transmitting said at least one data channel;

establishing wireless data communication from a transmitter of the mobile station to a receiver of the base station at a predetermined data rate using the received distinct spreading codes, the wireless data communication being simultaneously conducted through a fundamental code channel and a least one supplemental code channel;

receiving a first closed loop power control command from the base station, the first closed loop power control command requesting an increase in transmission power of the mobile station transmitter;

determining in the mobile station if the increased transmission power will exceed a transmission power threshold value;

if so, terminating data transmission through at least one supplemental code channel and increasing the transmission power;

receiving a second closed loop power control command from the base station, the second loop power control command requesting a decrease in transmission power of the mobile station transmitter;

determining in the mobile station if the decreased transmission power, assuming that data transmission through at least one previously terminated supplemental code channel is resumed, will be less than the transmission power threshold value;

if so, resuming data transmission through at least one previously terminated supplemental code channel by first transmitting a message from the mobile station to the base station over the resumed supplemental code channel for indicating that transmission is being resumed through the at least one previously terminated [disabled] supplemental data channel; and

decreasing the transmission power.

4. A method as set forth in claim 3, wherein the first step of determining uses a first power threshold value, wherein the second step of determining uses a second power threshold value, and wherein the first power threshold value does not equal the second power threshold value.

5. A method for operating a mobile station, comprising steps of:

establishing a wireless data communication from a transmitter of a mobile station at a predetermined data rate simultaneously through at least one data channel;

receiving a command to increase the transmission power of said mobile station transmitter;

determining in said mobile station that the increased transmission power will exceed a transmission power threshold value;

reducing said data rate by disabling data transmission through the at least one data channel;

increasing the transmission power;

receiving a command to decrease the transmission power of said mobile station;

determining in said mobile station that the decreased transmission power, assuming that the data rate were increased through the at least one previously reduced data channel, will be less than the transmission power threshold value;

increasing said data rate through the at least one previously reduced data channel; and

decreasing the transmission power.

6. An apparatus in a mobile station comprising:

means for establishing a wireless data communication from a transmitter of the mobile station to a receiver of the base station at a predetermined data rate simultaneously through a fundamental data channel and at least one supplemental data channel;

means for receiving a command from the base station to increase the transmission power of the mobile station transmitter;

means for determining in the mobile station if the increased transmission power will exceed a transmission power threshold value, and if so, reducing the data rate by disabling data transmission through the at least one supplemental data channel;

means for increasing the transmission power;

means for receiving a command from the base station to decrease the transmission power of the mobile station;

means for determining in the mobile station if the decreased transmission power, assuming that a disabled supplemental data channel were once more enabled, will be less than the transmission power threshold value, and if so, increasing the data rate by enabling data transmission through at least one previously disabled supplemental data channel; and

means for decreasing the transmission power.

7. An apparatus in a mobile station comprising:

means for establishing a wireless data communication from a transmitter of a mobile station at a predetermined data rate simultaneously through at least one data channel;

means for receiving a command to increase the transmission power of said mobile station transmitter;

means for determining in said mobile station that the increased transmission power will exceed a transmission power threshold value;

means for reducing said data rate by disabling data transmission through the at least one data channel;

means for increasing the transmission power;

means for receiving a command to decrease the transmission power of said mobile station;

means for determining in said mobile station that the decreased transmission power, assuming that the data rate were increased through the at least one previously reduced data channel, will be less than the transmission power threshold value;

means for increasing said data rate through the at least one previously reduced data channel; and

means for decreasing the transmission power.