Selective HARQ-ACK Bundling for Reduced Uplink Payload
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Reduced-capability wireless communication devices face limitations in uplink payload due to constrained HARQ-ACK codebook sizes, which restrict their ability to efficiently report successful or unsuccessful decoding of downlink transmissions, impacting system throughput and data rates.
Innovation Solution
The implementation of selective bundling techniques for HARQ-ACK feedback, where the HARQ-ACK codebook is compressed by bundling and unbundling bits based on predetermined rules, allowing reduced-capability devices to transmit a constrained codebook of limited size while ensuring all necessary data is reported, without compromising maximum data rates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If HARQ-ACK codebook size is reduced for reduced-capability devices, then uplink payload is reduced, but feedback information completeness deteriorates
Solution Approach 1:
The feedback information is segmented into two distinct parts: compressed feedback information (first portion) and uncompressed feedback information (second portion). This segmentation allows the system to transmit different types of feedback data through different channels or formats, ensuring that critical feedback is preserved while reducing overall uplink payload requirements for reduced-capability devices.
Solution Approach 2:
The patent extracts and separates essential feedback information from the complete HARQ-ACK codebook. By identifying and extracting the most critical feedback elements, the system can transmit a reduced codebook that contains only the most important feedback information, thereby reducing uplink payload while maintaining essential feedback functionality.
2Quantity of substance
If HARQ-ACK codebook is compressed, then uplink payload is reduced, but feedback transmission reliability deteriorates
Solution Approach 1:
Different portions of feedback information are treated with different quality requirements. The first portion (compressed feedback information) undergoes compression to reduce payload, while the second portion (uncompressed feedback information) maintains its original quality and detail. This local differentiation in quality treatment allows the system to optimize for both payload reduction and reliability where needed.
3Quantity of substance
If selective bundling is applied, then uplink payload is reduced, but device complexity increases
Solution Approach 1:
The selective bundling approach dynamically determines which feedback information to compress and which to leave uncompressed based on current transmission conditions, device capabilities, and feedback importance. This dynamic adaptation allows the system to optimize the balance between payload reduction and processing complexity in real-time, rather than using a static compression approach.
Data Source
AI summary
Apparatus, methods, and computer-readable media for managing HARQ-ACK processes in wireless user equipment (UEs) allow selective compression of HARQ-ACK information within HARQ-ACK codebooks. A wireless base station may transmit control information including scheduling information for K downlink transport blocks for a UE, and may signal bundling rules for selectively compressing an original HARQ-ACK codebook of size K into a constrained HARQ-ACK codebook of size N<K. Bundling rules can include the maximum codebook size N, a number M of bits that should not be bundled, criteria for bundling a plurality of the K−M bits into N−M bits, etc. The UE can apply a logical AND operation to ACK/NACK bits to produce one or more representative bundled bits. The base station identifies and schedules retransmission of packets associated with all of a bundled set of A/N bits if their representative bundled bit is NACK.