ARQ Feedback Message Overhead Reduction via Cumulative ACK
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional ARQ feedback messages in wireless portable Internet systems incur high overhead due to inefficient mapping of success and failure of data transmission, leading to increased data processing time and retransmission size.
Innovation Solution
A method is introduced to generate feedback messages by recording ACK types, last block sequence numbers, and lengths of successive ACK blocks, using a reduced number of bytes to minimize overhead, employing a cumulative-bulk ACK type that distinguishes between ACK and NACK blocks, and optimizing the configuration of ACK MAPs to reduce the size of the feedback message.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional ARQ feedback messages use detailed mapping of each data transmission result, then transmission accuracy is improved, but message overhead increases
Solution Approach 1:
The patent merges multiple individual transmission result indicators into a single cumulative ACK value. Instead of sending separate ACK/NACK signals for each transmitted packet, the system combines all results into one feedback message that indicates the highest sequence number successfully received, thereby reducing message overhead while maintaining transmission accuracy.
Solution Approach 2:
The patent uses selective acknowledgment where only the necessary portion of transmission results is fed back. Rather than reporting on every single packet, the system reports only up to the highest sequence number that needs acknowledgment, omitting redundant information for packets already confirmed as received, thus reducing overhead without sacrificing accuracy.
2Reliability
If conventional ARQ feedback messages include complete transmission status information, then error correction capability is improved, but data processing time increases
Solution Approach 1:
The patent extracts only the essential error correction information needed for retransmission decisions. By identifying and reporting only the highest sequence number that requires retransmission rather than including status for every packet, the system maintains error correction capability while significantly reducing the time required to process and transmit feedback messages.
3Productivity
If conventional ARQ uses selective ACK for each block, then retransmission efficiency is improved, but feedback message size increases
Solution Approach 1:
The patent combines multiple selective ACK indicators into a single cumulative acknowledgment value representing the highest sequence number successfully received. This merging approach maintains retransmission efficiency by accurately identifying which packets need retransmission while dramatically reducing feedback message size compared to sending individual ACKs for each block.
Data Source
AI summary
Provided is a method for generating a feedback message for ARQ including recording an ACK type in a first field; estimating the last block sequence number of successively ACKed blocks and recording the estimated last block sequence number in a second field; recording the number of groups of successively ACKed blocks after the estimated last block sequence number as the number of ACK MAPs in a third field; recording the startblock sequence number of the respective ACK MAPs in a fourth field; recording the lengths of the respective ACK MAPs in a fifth field corresponding to the recorded start block sequence number; and sending a feedback message including information on the first to the fifth fields.