PHICH Resource Allocation in Multi-Carrier Aggregation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current multi-carrier aggregation systems face challenges in efficiently transmitting and receiving physical channels in a broadband wireless access system, particularly in managing multiple carriers and reducing blind decoding overhead for user equipment (UE) in a multi-carrier environment.
Innovation Solution
A method for efficiently transmitting and receiving data in a broadband wireless access system using multiple carriers, where the user equipment (UE) receives uplink grant information through a first downlink component carrier, transmits data, and receives feedback information through a Physical Hybrid ARQ Indicator Channel (PHICH), allowing for reduced blind decoding overhead by not monitoring control regions of all downlink component carriers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the UE monitors control regions of all downlink component carriers to receive feedback information, then the reliability of receiving feedback is improved, but the blind decoding overhead and processing complexity increase significantly
Solution Approach 1:
The patent segments the feedback reception function by designating specific downlink component carriers (DL CCs) as PHICH transmission carriers. Instead of monitoring all DL CCs, the UE only monitors designated carriers for PHICH, dividing the monitoring task into essential and non-essential segments. This reduces blind decoding overhead while maintaining feedback reception reliability through targeted monitoring of carriers that actually carry PHICH transmissions.
Solution Approach 2:
The patent introduces an intermediary mechanism through higher layer signaling (RRC configuration) that specifies which DL CCs transmit PHICH. This intermediary configuration layer mediates between the need for reliable feedback delivery and the need to reduce UE processing complexity, allowing the network to control PHICH transmission locations while the UE follows predefined monitoring rules.
2Productivity
If the system uses multiple downlink component carriers for data transmission, then the data transmission capacity is improved, but the control channel management complexity increases
Solution Approach 1:
The patent merges the control channel management function by allowing a single DL CC to serve as the PHICH transmission carrier for multiple UL CCs. This consolidation reduces control channel management complexity while maintaining multi-carrier data transmission capacity, as the UE only needs to monitor one designated DL CC for PHICH feedback regardless of how many UL CCs are active.
Solution Approach 2:
The designated PHICH transmission DL CC performs multiple functions: it carries control information for multiple UL CCs and serves as the universal feedback channel for all uplink transmissions. This multi-functional approach simplifies control channel management while preserving the productivity benefits of multi-carrier operation.
3Reliability
If the UE monitors all downlink component carriers for PHICH, then the feedback reception reliability is improved, but the power consumption and processing time increase
Solution Approach 1:
The patent segments the PHICH reception function by configuring the UE to monitor only specific designated DL CCs for PHICH transmissions rather than all DL CCs. This segmentation reduces the number of control regions the UE must decode, thereby lowering power consumption and processing time while maintaining reliable PHICH reception through targeted monitoring of carriers that actually carry feedback information.
Solution Approach 2:
The patent applies partial action by having the UE monitor only a subset of DL CCs (those designated for PHICH transmission) rather than performing the complete action of monitoring all DL CCs. This partial monitoring approach is sufficient for reliable feedback reception while significantly reducing power consumption and processing requirements.
Data Source
AI summary
A method for receiving feedback information by a user equipment (UE) includes: receiving scheduling information from a base station through a first downlink component carrier linked with a first uplink component carrier; determining resources on a second uplink component carrier other than the first uplink component carrier using said scheduling information, wherein said scheduling information allows cross-carrier scheduling which schedules the resources on the second uplink component carrier; transmitting data to the base station through the determined resources on the second uplink component carrier; determining a PHICH (a Physical Hybrid ARQ Indicator Channel) resource to receive feedback information for the data transmitted on the second uplink component carrier, wherein the PHICH resource is predetermined as that of the first downlink component carrier in which the scheduling information was received; and receiving the feedback information from the base station through the determined PHICH resource.