Distributed Base Station HARQ via Local Quality Assessment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current centralized radio access networks face challenges with non-ideal backhaul latency, particularly in supporting Hybrid Automatic Repeat Request (HARQ) for LTE-Advanced systems, as moving Layer-1 processing to remote radio access points increases costs and complicates dynamic network deployment, while maintaining centralized processing is not feasible with strict delay requirements.
Innovation Solution
Remote radio access points locally assess data quality and radio conditions to decide on re-transmissions without decoding, reducing backhaul requirements and enabling centralized Layer-1 processing, allowing for low-complexity deployment with non-ideal backhaul without affecting the LTE-Advanced protocol stack.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If Layer-1 processing is moved to remote radio access points, then processing delay is reduced, but device complexity and deployment cost increase
Solution Approach 1:
The patent segments the base station functionality by separating the centralized processing entity from remote radio access points. The centralized entity handles complex decoding and HARQ decisions, while remote points perform only simple signal reception and quality assessment, dividing the processing burden to reduce individual device complexity while maintaining low latency.
Solution Approach 2:
The patent introduces quality indicators as an intermediary mechanism between remote radio access points and the centralized processing entity. Remote points assess signal quality and generate indicators without performing full decoding, enabling the centralized entity to make informed HARQ decisions with reduced backhaul requirements and lower remote point complexity.
2Device complexity
If centralized processing is maintained, then device complexity is reduced, but backhaul delay requirements become too strict
Solution Approach 1:
The patent implements preliminary action by having remote radio access points perform quality assessment and generate quality indicators before data transmission to the centralized entity. This pre-processing enables the centralized processing entity to quickly determine HARQ decisions without waiting for full data reception and analysis, effectively reducing the critical backhaul delay.
Solution Approach 2:
The patent extracts the time-critical quality assessment function from the centralized processing entity and places it at the remote radio access points. By taking out this function locally, the system eliminates the need for rapid backhaul transmission of raw data for quality determination, relaxing backhaul delay constraints while maintaining low device complexity at remote points.
3Productivity
If remote radio access points perform local HARQ processing with decoding, then response speed increases, but manufacturing cost increases
Solution Approach 1:
The patent employs cheap short-living objects by designing remote radio access points with simple, low-cost hardware that performs only quality assessment rather than full decoding. The complex decoding function is centralized, allowing remote points to be manufactured as low-cost devices that can be deployed in large numbers without requiring expensive dedicated processing hardware.
Solution Approach 2:
The patent substitutes the mechanical system of local decoding hardware with a software-based quality assessment mechanism at remote points, combined with centralized decoding. This replacement eliminates the need for expensive dedicated decoding hardware at each remote access point while maintaining fast HARQ response through efficient centralized processing and quality indicator-based decision making.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method for operating a distributed base station, wherein said distributed base station comprises a centralized processing entity (15), and a number of distributed remote radio access points (16), which are coupled to said centralized processing entity (15) via a backhaul connection (4), is characterized in that said remote radio access points (16) locally perform HARQ processing (12) by executing the steps of performing an assessment of the quality of received data and/or performing an assessment of current radio conditions, and, based on said assessment, deciding locally on the necessity of re-transmissions without decoding received data at said remote radio access points (16). Furthermore, a corresponding distributed base station architecture is described.