Method for the selection of forward error correction (FEC)/ constellation pairings for digital transmitted segments based on learning radio link adaptation (RLA)

• US 7,471,620 B2
• Filed: 09/30/2004
• Issued: 12/30/2008
• Est. Priority Date: 09/30/2004
• Status: Expired due to Fees

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Chaudhri, Apoorv, Conrad, Alan P., Pinder, Ellis A., Stogner, Darrell J., Lampert, Chet A., Alazraki, Scott M., Logalbo, Bob D., Jelavic, Stanko
• Primary Examiner(s): Ngo; Ricky
• Assistant Examiner(s): Mui; Gary
• Application Number:
  US10/955,554
• Publication Number:
  US 20060067256A1
• Time in Patent Office: 1,552 Days
• Field of Search: 370/204, 370/207, 370/252, 370/253, 370/229, 370/300, 370/301, 370/442, 370/465, 375/298, 375/265
• US Class Current: 370/204
• 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 1/0019 in which mode-switching is based on a statistical approach
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/1867 Arrangements specially adapted for the transmitter end

Abstract

A method for the selection of forward error correction (FEC)/constellation pairings (800) for digital transmitted segments based on learning radio link adaptation (RLA) including formatting a packet transmission having a predetermined number of information bits (801). The packet is then split into a plurality of segments (803) where an RLA is used (805) to determine the optimum format of the packet. The plurality of segments is then sent to a channel encoder for FEC encoding and symbol mapping (807) at a rate selected by the RLA. The segments are then formatted into packet blocks (809) and transmitted in blocks that form a time slot at a constant symbol rate.

Claims

1. A method for the selection of forward error correction (FEC)/constellation pairings for digital transmitted segments

comprising the steps of:

formatting a packet transmission having a predetermined number of information bits;

splitting the packet into a plurality of segments where each segments as an identical number of bits;

utilizing a learning radio link adaptation (RLA) to determine an optimum format for the plurality of segments based upon current values of learning RLA input parameters and maintained statistics on learning RLA input parameters from previous confirmed transmissions;

sending the plurality of segments to a channel encoder for FEC encoding and symbol mapping at a rate selected by the learning RLA;

formatting the segments into packet blocks; and

transmitting the blocks that form a time slot at a constant symbol rate.

2. The method of claim 1 wherein the learning RLA selects from at least one of a group of learning RLA input parameters comprising:

modulation and code rate pairings based upon previously transmitted pairings, successful acknowledgement of previous transmissions, signal quality estimation at the time of transmission, geographic location and velocity of the transmitter.

3. The method of claim 2, wherein maintained statistics on learning RLA input parameters from previous transmissions are shared from an existing mobile unit with new mobile units.

4. The method of claim 2, wherein maintained statistics on learning RLA input parameters from previous transmissions are shared from an existing base unit with new base units.

5. The method of claim 2 farther comprising the step of sharing maintained statistics on learning RLA input parameters from previous transmissions.

6. The method of claim 5, wherein the step of sharing comprises the steps of:

dividing a system into a plurality of zones;

storing into the system a profile of previous transmission parameters associated with each zone; and

sharing the profile with a mobile unit as it migrates into a zone of the plurality of zones.

7. The method of claim 5, wherein the step of sharing comprises the steps of:

transmitting the maintained statistics from previous transmissions from a plurality of mobile units to a base unit;

combining the maintained statistics from the plurality of mobile units into a database; and

transmitting the combined statistics of the database from the base unit to the plurality of mobile units.

8. A method comprising the steps of:

providing a communication channel having a plurality of time slots, wherein each of the plurality of time slots has a common duration;

providing a quantity of information bits to be transmitted to at least one intended recipient;

providing a plurality of modulation techniques having corresponding effective data transmission rates;

selecting one of the plurality of modulation techniques to produce a selected modulation technique by utilizing a learning radio link adaptation (RLA) based on current values of learning RLA input parameters and maintained statistics on learning RLA input parameters from previous confirmed transmissions;

regardless of which of the plurality of modulation techniques was selected;

formatting the information bits into at least one block, such that an identical number of information bits are always contained within a single block; and

transmitting the at least one block in at least one of the time slots at a predetermined constant symbol rate using the selected modulation technique.

9. The method of claim 8, wherein the learning radio link adaptation includes using at least one from the group of modulation rate, code rate pairing, received acknowledgement, signal quality estimation (SQE), transmitter geographical location and transmitter movement and velocity.

10. The method of claim 8, wherein the step of transmitting the at least one block in at least one of the time slots includes the step of transmifting the at least one block such that all of the time slots will only contain an integer number of the blocks.

11. The method of claim 8, wherein the step of providing a communication channel includes the step of providing a communication channel that is one of a plurality of communication channels, wherein the plurality of communication channels are offset from adjacent communication channels by either 25 kHz, 50 kHz, 100 kHz or 150 kHz.

12. The method of claim 11, wherein the step of providing a communication channel having a plurality of time slots includes the step of providing a communication channel having a plurality of time slots, wherein each time slot has a duration of 30 milliseconds for 25 kHz communication channels and 10 milliseconds for 50 kHz, 100 kHz and 150 kHz communication channels.

13. The method of claim 8, wherein the step of providing a plurality of modulation techniques includes the step of providing a plurality of modulation techniques, including but not limited to a group comprised of quadrature phase shift keying (QPSK) ½

rate;

QPSK uncoded, 16 quadrature amplitude modulation (QAM) ½

rate, 64 QAM ½

rate, 16 QAM uncoded, 64 QAM ⅔

rate and 64 QAM uncoded.

14. The method of claim 13, wherein the group of modulation techniques includes error correction coding and a variable information bit-to-symbol transmitted symbol ratio.

15. The method of claim 8, wherein the step of selecting one of the plurality of modulation techniques includes the step of selecting a predetermined one of the plurality of modulation techniques as an initial default selection.

16. The method of claim 8, wherein the step of formatting the information bits into at least one block includes the step of formatting the information bits into at least one block, wherein the information bits include both user data and cyclic redundancy check error detection coding.

17. The method of claim 8, wherein the step of formatting the information bits into at least one block includes the step of formatting the information bits into at least one block, wherein the information bits include both user data and error detection coding.

18. The method of claim 8, wherein the step of transmitting the at least one block in at least one of the time slots at a predetermined constant symbol rate using the selected modulation technique such that the number of symbols per slot used to communicate user or signaling data depends upon the channel bandwidth and transmission direction and is:

324 symbols per slot for 25 kHz inbound, 348 symbols per slot for 25 kHz outbound, 252 symbols per slot for 50 kHz inbound, 276 symbols per slot for 50 kHz outbound, 552 symbols per slot for 100 kHz inbound, 612 symbols per slot for 100 kHz outbound, 852 symbols per slot for 150 kHz inbound, 948 symbols per slot for 150 kHz outbound.

19. The method of claim 8, wherein the step of formatting the information bits into at least one block, such that an identical number of information bits are always contained within a single block includes the step of formatting the information bits into at least one block, such that the following number of information bits are always contained within a single block:

324 bits for 25 kHz inbound, 348 bits for 25 kHz outbound, 252 bits for 50 kHz inbound, 276 bits for 50 kHz outbound, 552 bits for 100 kHz inbound, 612 bits for 100 kHz outbound, 852 bits for 150 kHz inbound, 948 bits for 150 kHz outbound.

20. The method of claim 19, wherein the step of providing a plurality of modulation techniques includes the step of providing a plurality of modulation techniques, further comprising but not limited to a group comprised of quadrature phase shift keying (QPSK) ½

rate;

QPSK uncoded, 16 quadrature amplitude modulation (QAM) ½

rate, 64 QAM ½

rate, 16 QAM uncoded, 64 QAM ⅔

rate and 64 QAM uncoded.

21. The method of claim 20, wherein the group of modulation techniques includes error correction coding and a variable information bit-to-symbol transmitted symbol ratio.

22. A method for transmitting user data through a wireless communication medium using at least one of a plurality of modulation techniques having corresponding effective data transmission rates, comprising the steps of:

providing a communication channel having a plurality of time slots, wherein each of the plurality of time slots has a predetermined duration;

providing a quantity of information bits to be transmitted to at least one intended recipient, wherein the information bits include both user data and error detection coding bits;

providing a plurality of modulation techniques;

selecting one of the plurality of modulation techniques based upon learning radio link adaptation (RLA) to produce a selected modulation technique based upon current values of learning RLA input parameters and maintained statistics on learning RLA input parameters from previous confirmed transmissions;

formatting the information bits using the selected modulation technique into at least one block, such that an identical number of information bits are always contained within a single block; and

transmitting the at least one block in at least one of the time slots at a predetermined constant symbol rate using the selected modulation technique.

23. The method of claim 22, wherein the learning radio link adaptation includes selecting the modulation technique based upon at least one of the group of:

modulation and code rate pairings previously transmitted, successful acknowledgement of previous transmissions, signal quality estimation at the time of transmission, geographic location and velocity of the transmitter.

24. The method of claim 22, wherein the at least one of a plurality of modulation techniques includes but is not limited to a group consisting of quadrature phase shift keying (QPSK) ½

rate;

QPSK uncoded, 16 quadrature amplitude modulation (QAM) ½

rate, 64 QAM ½

rate, 16 QAM uncoded, 64 QAM ⅔

rate and 64 QAM uncoded.

25. The method of claim 24, wherein the group of modulation techniques includes error rate coding and a variable information bit-to-transmitted symbol ratio.

26. The method of claim 22, further comprising sharing statistics of the learning RLA input parameters amongst existing and new units.