Relay HARQ Scheduling for Coverage and Power Saving
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless communication systems fail to effectively increase relay system coverage while employing power saving mechanisms for relay stations and lack procedures for managing load conditions such as data and acknowledgment packets.
Innovation Solution
A base station with multiple antennas and a transmitter configured to transmit transport blocks for Hybrid Automatic Repeat Request (HARQ) processes, semi-statically configuring the relay physical downlink control channel (R-PDCCH) region to manage downlink and uplink scheduling assignments, allowing multiple HARQ processes to be received and transmitted in a subframe.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If relay stations are added to increase coverage range and user data rates, then relay system coverage is improved, but power consumption increases and load management complexity worsens
Solution Approach 1:
The patent implements discontinuous reception (DRX) cycles where the relay station alternates between active listening periods and sleep periods. During DRX cycles, the relay station wakes up at specific intervals to check for scheduling assignments and receives data only when necessary, then returns to sleep mode. This periodic operation pattern significantly reduces power consumption while maintaining coverage extension capability, as the relay station is fully operational only during brief active windows rather than continuously.
2Productivity
If multiple transport blocks for multiple HARQ processes are transmitted in a subframe, then data transmission efficiency is improved, but processing complexity and error management difficulty worsen
Solution Approach 1:
The patent divides the downlink data transmission into multiple independent transport blocks, each associated with a separate HARQ process identifier. The relay station receives and buffers these segmented transport blocks independently, allowing parallel processing and individual retransmission management. This segmentation enables efficient utilization of multiple HARQ processes simultaneously within a single subframe, improving overall data transmission efficiency while maintaining manageable complexity through independent process handling.
Solution Approach 2:
The patent introduces a scheduling assignment message as an intermediary control element that carries HARQ process identifiers and scheduling information. This intermediary message coordinates between the base station and relay station, enabling the relay station to correctly identify and manage multiple transport blocks belonging to different HARQ processes. The scheduling assignment acts as a mediator that organizes the complex multi-process transmission into manageable units, reducing error management difficulty while maintaining high transmission efficiency.
3Productivity
If R-PDCCH region is semi-statically configured with separate OFDM symbol sets for downlink and uplink scheduling, then resource allocation efficiency is improved, but control channel complexity increases
Solution Approach 1:
The patent extends the control channel configuration into the time dimension by allocating specific OFDM symbol sets within a subframe for downlink and uplink scheduling assignments. Instead of mixing control and data in the same time resources, the patent creates separate time slots (symbol dimensions) for different scheduling types. This dimensional separation in the time domain improves resource allocation efficiency by preventing control-data conflicts and enabling more flexible resource scheduling, while the semi-static configuration reduces control channel complexity through predictable, pre-defined patterns.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A wireless communication network includes a base station and a relay station. The relay station is configured to relay communications between the base station and at least one subscriber station. The base station is configured to communicate with the subscriber station via the relay station. The base station further is configured to transmit, in a subframe, a plurality of transport blocks for a plurality of Hybrid Automatic Repeat Request (HARQ) processes to the relay station. Each transport block corresponds to a different HARQ process.