Method and apparatus for providing high speed data communications in a cellular environment

• US 20020106015A1
• Filed: 03/29/2002
• Published: 08/08/2002
• Est. Priority Date: 10/29/1996
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Zehavi, Ephraim
• Granted Patent: US 7,949,066 B2
• Time in Patent Office: Days
• US Class Current: 375/225
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0072 Error control for data other than payload data, e.g. control data
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 28/18 Negotiating wireless communication parameters
• CPC Class Codes: H04W 28/22 Negotiating communication rate
• CPC Class Codes: H04W 72/0473 the resource being transmission power
• CPC Class Codes: H04W 72/54 based on quality criteria
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method and apparatus for transmitting digital data in a cellular environment. Adjacent cells of the cellular system are prevented from simultaneously transmitting data. Because the noise from transmissions of adjacent cells is a primary source of interference, the transmission rate of power limited base stations can be dramatically increased when the noise from adjacent cells is eliminated. The transmissions to each subscriber station are made at a fixed transmission power level. However, the data rate of transmitted signals differs from one subscriber station to another depending the path loss differences. In a first exemplary embodiment, the data rate of transmissions to a subscriber station is determined by selecting an encoding rate for the transmitted signal while holding the symbol rate constant. In a second exemplary embodiment, the data rate of transmissions to a subscriber station is determined by selection a modulation format for the transmitted signal which directly changes the symbol rate of transmission to a subscriber station.

Claims

1. A method of determining an information rate for a signal to be transmitted over the air from an infrastructure element to a remote unit in a wireless communication system, the signal including an information component and a channel encoding component, the method comprising:

receiving from the remote unit, at the infrastructure element, information indicative of a quality measure of a wireless channel for communications between the infrastructure element and the remote unit; and

selecting, at the infrastructure element, based on the received quality measure, a channel encoding rate at which to encode the signal for transmission during a particular time period.

2. The method of claim 1, wherein the receiving comprises receiving information indicative of a measure of path loss between the infrastructure element and the remote unit.

3. The method of claim 1, wherein the selecting causes the channel encoding component to include a first predefined quantity of bits, which thereby causes the information component to include a second predefined quantity of bits, which thereby determines the information rate for the particular time period.

4. The method of claim 3, further comprising transmitting the signal during the particular time period.

5. The method of claim 2, further comprising transmitting the signal during the particular time period.

6. The method of claim 1, wherein the selecting comprises selecting a channel encoding rate from among a predefined plurality of channel encoding rates.

7. An infrastructure element configured to determine an information rate for a signal to be transmitted over the air to a remote unit in a wireless communication system, the signal including an information component and a channel coding component, the infrastructure element comprising:

means for receiving information indicative of a quality measure of a wireless channel for communications between the infrastructure element and the remote unit; and

means for selecting, based on the received quality measure, a channel coding rate at which to encode the signal for transmission during a particular time period.

8. The infrastructure element of claim 7, wherein the means for receiving comprises means for receiving information indicative of a measure of path loss between the infrastructure element and the remote unit.

9. The infrastructure element of claim 7, wherein the means for selecting causes the channel encoding component to include a first predefined quantity of bits, which thereby causes the information component to include a second predefined quantity of bits, which thereby determines the information rate for the particular time period.

10. The infrastructure element of claim 9, further comprising means for transmitting the signal during the particular time period.

11. The infrastructure element of claim 8, further comprising means for transmitting the signal during the particular time period.

12. The infrastructure element of claim 7, wherein the means for selecting comprises means for selecting a channel encoding rate from among a predefined plurality of channel encoding rates.

14. The infrastructure element of claim 13, wherein the information is information indicative of a measure of path loss between the infrastructure element and the remote unit.

15. The infrastructure element of claim 13, wherein the controller causes the channel encoding component to include a first predefined quantity of bits, which thereby causes the information component to include a second predefined quantity of bits, which thereby determines the information rate for the particular time period.

16. The infrastructure element of claim 15, further comprising a transmitter coupled to the controller and configured to transmit the signal during the particular time period.

17. The infrastructure element of claim 14, further comprising a transmitter coupled to the controller and configured to transmit the signal during the particular time period.

18. The infrastructure element of claim 13, wherein the selector is configured to select a channel encoding rate from among a predefined plurality of channel encoding rates.

20. The method of claim 19, wherein the transmitting comprises transmitting information indicative of a measure of path loss between the infrastructure element and the remote unit.

21. The method of claim 19, wherein the transmitting comprises transmitting information indicative of a measure of distance between the infrastructure element and the remote unit.

22. The method of claim 19, wherein the transmitting comprises transmitting information indicative of a measure of an effective distance between the infrastructure element and the remote unit.

24. The remote unit of claim 23, wherein the means for transmitting comprises means for transmitting information indicative of a measure of path loss between the infrastructure element and the remote unit.

25. The remote unit of claim 23, wherein the means for transmitting comprises means for transmitting information indicative of a measure of distance between the infrastructure element and the remote unit.

26. The remote unit of claim 23, wherein the means for transmitting comprises means for transmitting information indicative of a measure of an effective distance between the infrastructure element and the remote unit.

28. The remote unit of claim 27, wherein the information indicative of a quality measure includes information indicative of a measure of path loss between the infrastructure element and the remote unit.

29. The remote unit of claim 27, wherein the information indicative of a quality measure includes information indicative of a measure of distance between the infrastructure element and the remote unit.

30. The remote unit of claim 27, wherein the information indicative of a quality measure includes information indicative of a measure of an effective distance between the infrastructure element and the remote unit.

13. An infrastructure element configured to determine an information rate for a signal to be transmitted over the air to a remote unit in a wireless communication system, the signal including an information component and a channel coding component, the infrastructure element comprising:

a receiver configured to receive information indicative of a quality measure of a wireless channel for communications between the infrastructure element and the remote unit; and

a controller coupled to the receiver and configured to select, based on the received quality measure, a channel coding rate at which to encode the signal for transmission during a particular time period.

19. A method of requesting an information rate for a signal received at a remote unit and transmitted by an infrastructure element to the remote unit over a wireless channel, the method comprising:

transmitting from the remote unit to the infrastructure element information indicative of a quality measure of the wireless channel; and

receiving at the remote unit a signal having an information rate that is based on the quality measure of the wireless channel.

23. A remote unit configured to request an information rate for a signal received at the remote unit and transmitted by an infrastructure element to the remote unit over a wireless channel, the remote unit comprising:

means for transmitting to the infrastructure element information indicative of a quality measure of the wireless channel; and

means for receiving a signal having an information rate that is based on the quality measure of the wireless channel.

27. A remote unit configured to request an information rate for a signal received at the remote unit and transmitted by an infrastructure element to the remote unit over a wireless channel, the remote unit comprising:

a transmitter configured to transmit to the infrastructure element information indicative of a quality measure of the wireless channel; and

a receiver configured to receive a signal having an information rate that is based on the quality measure of the wireless channel.