Method and apparatus for fast closed-loop rate adaptation in a high rate packet data transmission

• US 7,245,594 B1
• Filed: 05/12/2000
• Issued: 07/17/2007
• Est. Priority Date: 05/12/2000
• Status: Expired due to Term

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Attar, Rashid A., Sindhushayana, Nagabhushana T., Esteves, Eduardo A. S.
• Primary Examiner(s): To; Doris H.
• Assistant Examiner(s): Nguyen; Phuongchau Ba
• Application Number:
  US09/570,210
• Time in Patent Office: 2,622 Days
• Field of Search: 370/395.2, 370/442, 370/232, 370/243, 370/230.1, 370/352, 370/252, 370/253, 370/335, 370/340, 370/412, 370/337, 370/450, 370/451, 370/454, 370/458, 370/459, 370/468, 370/452, 370/322, 370/348, 370/347, 370/524, 375/225, 375/133, 375/227, 375/222, 455/69, 455/62, 455/67.11, 455/67.13, 455/452.2, 455/450, 455/436, 455/509, 455/519, 340/502, 340/825.25
• US Class Current: 370/322
• CPC Class Codes: H04W 16/02 Resource partitioning among network components, e.g. reuse partitioning
• CPC Class Codes: H04W 28/04 Error control
• CPC Class Codes: H04W 28/18 Negotiating wireless communication parameters

Abstract

In a high data rate communication system capable of variable rate transmission, an open loop rate control can be adjusted with a closed loop rate control to maximize throughput. An access point generates interleaved multi-slot packets that allow an access terminal to transmit indicator messages to the access point in accordance with recently received data carried within slots of the multi-slot packets.

Claims

1. A method for increasing the data throughput rate of a communication network, comprising:

generating a plurality of interleaved data slots and gap slots at an access point, wherein the plurality of interleaved data slots and gap slots form at least one packet;

transmitting the at least one packet to an access terminal at a particular data rate;

receiving at least one indicator message from the access terminal during a time period associated with at least one gap slot indicating a reception status, wherein the indicator message comprises a bit received during a slot n, and the access point designates each slot in accordance with an alternating pattern,; and

modifying a subsequent data packet for transmission to the access terminal in accordance with the indicator message received at the access point, wherein modifying the subsequent data packet for transmission to the access terminal comprises;

deciding the bit is a request for a termination of transmission if a repetition of one of the plurality of data packets is already scheduled for slot n+1;

deciding the bit is a request for retransmission if an already transmitted packet ended transmission in slot n−

1;

deciding the bit is a request for retransmission if a previous indicator bit caused a retransmission of an already transmitted packet in slot n−

1 and fewer than a predetermined number of retransmissions have been already processed for the plurality of data packets; and

deciding the bit is a false alarm if no conditions are satisfied.

2. A method for increasing the data throughput rate for transmissions from an access point to an access terminal, comprising:

generating a plurality of data packets at the access point for transmission to the access terminal, wherein each of the plurality of data packets comprises at least one slot, and the access point designates each slot in each of the plurality of data packets as a data slot or a gap slot;

transmitting the plurality of data packets to the access terminal at an initial data rate in accordance with a data request message determined at an access terminal, based on estimated channel parameters;

receiving an indicator message from the access terminal if a set of actual channel parameters determined at the access terminal passes a predetermined quality amount, wherein the indicator message comprises a bit received during a slot n, and associated with at least one gap slot, and the access point designates each slot in the plurality of data packets in accordance with an alternating pattern; and

modifying a subsequent data packet for transmission to the access terminal in accordance with the indicator message received at the access point, wherein modifying the subsequent data packet comprises;

deciding the bit is a request for a termination of transmission if a repetition of one of the plurality of data packets is already scheduled for slot n+1;

deciding the bit is a request for retransmission is an already transmitted packet ended transmission in slot n−

1;

deciding the bit is a request for retransmission if a previous indicator bit caused a retransmission of an already transmitted packet in slot n−

1 and fewer than a predetermined number of retransmissions have been already processed for the plurality of data packets; and

deciding the bit is a false alarm if no conditions are satisfied.

10. The method as in any of claim 2, 8, or 9, wherein the indicator message is a stop indicator message if the set of actual channel parameters indicates a noise level less than a noise level associated with the set of estimated channel parameters.

11. The method as in any of claim 2, 8 or 9, wherein the indicator message is an extend indicator message in the set of actual channel parameters indicates a noise level greater than a noise level associated with the set of estimated channel parameters.

12. The method as in any of claim 2, 8 or 9, wherein the set of actual channel parameters comprises a signal-to-interference and noise ratio.

13. The method as in any of claim 2, 8 or 9, wherein the set of actual channel parameters determined at the access terminal are generated by decoding the plurality of data packets at the access terminal to determine a packet error event, wherein the packet error event indicates a good data packet reception or a bad data packet reception.

3. A system for increasing the data throughput rate of transmissions from an access point to an access terminal, comprising a processor at the access point configured to generate a plurality of interleaved data slots and gap slots in an alternating pattern for transmission to the access terminal, and to modify a subsequent data packet for transmission to the access terminal in accordance with an indicator message received at the access point during a slot n, and associated with at least one gap slot, wherein the indicator message comprises a bit, and the access point designates each slot in the plurality of data packets in accordance with an alternating pattern, wherein modifying the subsequent data packet for transmission to the access terminal comprises:

deciding the bit is a request for a termination of transmission if a repetition of one of the plurality of data packets is already scheduled for slot n+1;

deciding the bit is a request for retransmission if an already transmitted packet ended transmission in slot n−

1;

deciding the bit is a request for retransmission if a previous indicator bit caused a retransmission of an already transmitted packet in slot n−

1 and fewer than a predetermined number of retransmission have been already processed for the plurality of data packets; and

deciding the bit is a false alarm if no conditions are satisfied.

4. An apparatus for adjusting an open loop rate control process, comprising:

a scheduler at an access point for scheduling a plurality of interleaved data slots and gap slots in an alternating pattern for transmission to an access terminal at a particular data rate wherein the number of gap slots is determined by the data rate, wherein the scheduler is coupled to at least one buffer that stores data to be transmitted on a forward link channel;

a data rate request message decoder coupled to the scheduler for decoding a plurality of data request messages received on a reverse link channel, and for inputting data rate request information to the scheduler;

an indicator message decoder coupled to the scheduler for decoding the plurality of indicator messages received on the reverse link channel and for inputting decoded indicator messages to the scheduler; and

a subsequent data packet for transmission to the access terminal in accordance with the indicator message received at the access point.

5. An apparatus for adjusting an open loop rate control process, comprising:

an estimation element at the access terminal for determining a quality value associated with a forward link channel;

an open loop rate control element coupled to the estimation element for generating a plurality of data rate request messages, wherein the open loop rate control element uses the quality value received from the estimation element for the determining the contents of the plurality of data rate request messages;

a closed loop rate control element coupled to the estimation element and a decoder for generating a plurality of indicator messages based on either the quality value from the estimation element or an error value from the decoder, wherein the decoder is configured to decode a plurality of interleaved data slots and gap slots in an alternating pattern received on the forward link channel at a particular data rate wherein the number of gap slots is determined by the data rate;

a controller coupled to the decoder and the estimation element for enabling the closed loop rate control element in accordance with a set of threshold values; and

a subsequent data packet for transmission to the access terminal in accordance with the indicator message received at the access point.

6. A method for increasing the data throughput rate of a communication network, comprising:

generating a plurality of interleaved data slots and gap slots at an access point, wherein the plurality of interleaved data slots and gap slots form at least one packet;

transmitting the at least one packet to an access terminal at a particular data rate;

receiving at least one indicator message from the access terminal during a time period associated with at least one gap slot indicating a reception status, wherein the indicator message comprises a bit received during a slot n, and the access point designates each slot in accordance with a period p; and

modifying a subsequent data packet for transmission to the access terminal in accordance with the indicator message received at the access point, wherein modifying the subsequent data packet for transmission to the access terminal comprises;

deciding the bit is a request for a termination of transmission of a repetition of one of the plurality of data packets is already scheduled for slot n+1;

deciding the bit is a request for retransmission if an already transmitted packet ended transmission in slot n−

p+1;

deciding the bit is a request for retransmission if a previous indicator bit caused a retransmission of an already transmitted packet in slot n−

p+1, and fewer than a predetermined number of retransmission have been already processed for the plurality of data packets; and

deciding the bit is a false alarm if no conditions are satisfied.

7. A method for increasing the data throughput rate of a communication network, comprising:

generating a plurality of interleaved data slots and gap slots at an access point, wherein the plurality of interleaved data slots and gap slots form at least one packet;

transmitting the at least one packet to an access terminal at a particular data rate;

receiving at least one indicator message from the access terminal during a time period associated with at least one gap slot indicating a reception status, wherein the indicator message comprises a bit received during a slot n; and

modifying a subsequent data packet for transmission to the access terminal in accordance with the indicator message received at the access point, wherein modifying the subsequent data packet for transmission to the access terminal comprises;

deciding the bit is a request for a termination of transmission if a repetition of one of the plurality of data packets is already scheduled for slot n+1;

deciding the bit is a request for retransmission if an already transmitted packet ended transmission in slot n−

N(i), wherein N(i) is the number of gap slots between data slots and i indicates a data rate index number;

deciding the bit is a request for retransmission if a previous indicator bit caused a retransmission of an already transmitted packet in slot n−

N(i), and fewer than a predetermined number of retransmission have been already processed for the plurality of data packets; and

deciding the bit is a false alarm if no conditions are satisfied.

8. A method for increasing the data throughput rate for transmission from an access point to an access terminal, comprising:

generating a plurality of data packets at the access point for transmission to the access terminal, wherein each of the plurality of data packets comprises at least one slot, and the access point designates each slot in each of the plurality of data packets as a data slot or a gap slot;

transmitting the plurality of data packets to the access terminal at an initial data rate in accordance with a data request message determined at an access terminal, based on estimated channel parameters;

receiving an indicator message from the access terminal if a set of actual channel parameters determined at the access terminal passes a predetermined quality amount, wherein the indicator message comprises a bit received during a slot n and is associated with at least one gap slot, and the access point designates each slot in the plurality of data packets in accordance with a period p; and

modifying a subsequent data packet for transmission to the access terminal in accordance with the indicator message received at the access point, wherein modifying the subsequent data packet for transmission to the access terminal comprises;

deciding the bit is a request for a termination of transmission if a repetition of one of the plurality of data packets is already scheduled for slot n+1;

deciding the bit is a request for retransmission if an already transmitted packet ended transmission in slot n−

p+1;

deciding the bit is a request for retransmission if a previous indicator bit caused a retransmission of an already transmitted packet in slot n−

p+1, and fewer than a predetermined number of retransmissions have been already processed for the plurality of data packets; and

deciding the bit is a false alarm if no conditions are satisfied.

9. A method for increasing the data throughput rate for transmission from an access point to an access terminal, comprising:

generating a plurality of data packets at the access point for transmission to the access terminal, wherein each of the plurality of data packets comprises at least one slot, and the access point designates each slot in each of the plurality of data packets as a data slot or a gap slot;

transmitting the plurality of data packets to the access terminal at an inital data rate in accordance with a data request message determined at an access terminal, based on estimated channel parameters;

receiving an indicator message from the access terminal if a set of actual channel parameters determined at the access terminal passes a predetermined quality amount, wherein the indicator message comprises a bit received during a slot n and associated with at least one gap slot; and

modifying a subsequent data packet for transmission to the access terminal in accordance with the indicator message received at the access point, wherein modifying the subequent data packet for transmission to the access terminal comprises;

deciding the bit is a request for a termination of transmission if a repetition of one of the plurality of data packets is already scheduled for slot n+1;

deciding the bit is a request for retransmission if an already transmitted packet ended transmission in slot n−

N(i), wherein N(i) is the number of gap slots between data slots and i indicates a data rate index number;

deciding the bit is a request for retransmission if a previous indicator bit caused a retransmission of an already transmitted packet in slot n−

N(i), and fewer than a predetermined number of retransmissions have been already processed for the plurality of data packets; and

deciding the bit is a false alarm if no conditions are satisfied.

14. A system for increasing the data throughput rate of transmission from an access point to an access terminal, comprising a processor at the access point configured to generate a plurality of interleaved data slots and gap slots in an alternating pattern for transmission to the access terminal, and to modify a subsequent data packet for transmission to the access terminal in accordance with an indicator message received at the access point during a slot n, and associated with at least one gap slot, wherein the indicator message comprises a bit, and the access point designates each slot in the plurality of data packets in accordance with a period p, wherein modifying the subsequent data packet for transmission to the access terminal comprises:

deciding the bit is a request for a termination of transmission if a repetition of one of the plurality of data packets is already scheduled for slot n+1;

deciding the bit is a request for retransmission if an already transmitted packet ended transmission in slot n−

p+1;

deciding the bit is a request for retransmission if a previous indicator bit caused a retransmission of an already transmitted packet in slot n−

p+1, and fewer than a predetermined number of retransmissions have been already processed for the plurality of data packets; and

deciding the bit is a false alarm if no conditions are satisfied.

16. The system as in any of claim 3, 14 or 15, further comprising a processor at the access terminal configured to decode the plurality of interleaved data slots and gap slots, determine a quality value associated with transmissions from the access point to the access terminal, generate data rate request messages for transmission in accordance with the quality value, and generate indicator messages in accordance with the quality value, wherein the indicator message is generated and transmitted to the access point during a time period associated with at least one gap slot.

17. The apparatus of claim 16, wherein the quality value is determined by a channel noise and interference value.

18. The apparatus of claim 16, wherein the quality value is determined by a packet error value based on the decoded plurality of data slots.

15. A system for increasing the data throughput rate of transmissions from an access point to an access terminal, comprising a processor at the access point configured to generate a plurality of interleaved data slots and gap slots in an alternating pattern for transmission to the access terminal, and to modify a subsequent data packet for transmission to the access terminal in accordance with an indicator message received at the access point during a slot n, and associated with at least one gap slot, wherein the indicator message comprises a bit, and modifying the subsequent data packet for transmission to the access terminal comprises:

deciding the bit is a request for a termination of transmission if a repetition of one of the plurality of data packets is already scheduled for slot n+1;

deciding the bit is a request for retransmission if an already transmitted packet ended transmission in slot n−

N(i), wherein N(i) is a number of gap slots between data slots and i indicates a data rate index number;

deciding the bit is a request for retransmission if a previous indicator bit caused a retransmission of an already transmitted packet in slot n−

N(i), and fewer than a predetermined number of retransmissions have been already processed for the plurality of data packets; and

deciding the bit is a false alarm if no conditions are satisfied.