Uplink Feedback Channel Allocation for E-PDCCH
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In 3GPP LTE systems, the overhead generated for a base station to determine whether data packets are successfully decoded by terminals is high, reducing overall system efficiency, due to the need for extensive feedback mechanisms.
Innovation Solution
A method where terminals allocate acknowledgement (ACK) or negative acknowledgement (NACK) information for data packet decoding success to resource areas of the uplink feedback channel, using indices of control channel elements (CCEs) from multiple resource allocation control channels, minimizing overhead by optimizing the mapping and allocation of feedback information.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a base station uses extensive feedback mechanisms to determine whether data packets are successfully decoded, then the reliability of data transmission is improved, but the overhead generated increases, reducing overall system efficiency
Solution Approach 1:
The patent segments the feedback mechanism by associating specific resource areas in the uplink feedback channel with specific CCE aggregations in the downlink control channel. Each resource area corresponds to a specific set of CCEs, allowing the base station to receive feedback only for the control information that was actually transmitted, thereby reducing unnecessary overhead while maintaining reliability for actual data transmissions.
Solution Approach 2:
The patent introduces resource areas in the uplink feedback channel as intermediaries between the downlink control channel and the feedback information. These resource areas serve as a mapping mechanism that connects CCE aggregations to feedback resources, enabling efficient feedback transmission without requiring separate control messages for each feedback item.
2Ease of operation
If the base station transmits resource allocation information via control channels, then the control of data transmission is improved, but the overhead for feedback mechanisms increases
Solution Approach 1:
The patent makes the resource areas in the uplink feedback channel serve multiple functions: they not only carry feedback information but also serve as the mapping mechanism itself. The same resource areas that receive feedback are determined by the CCE aggregation indices, eliminating the need for separate control messages to specify feedback resources, thus reducing complexity while maintaining control efficiency.
Solution Approach 2:
The feedback mechanism is designed to be self-configuring through the mapping between CCE aggregation indices and resource area indices. The base station and terminal automatically determine the correct feedback resources based on the transmitted control information, without requiring additional configuration messages, thereby simplifying the overall system operation.
3Measurement precision
If separate control messages are used to allocate feedback channels, then the accuracy of feedback allocation is improved, but the overhead increases
Solution Approach 1:
The patent merges the feedback allocation information with the existing control channel structure by using CCE aggregation indices to directly determine resource area indices. This integration eliminates the need for separate control messages to specify feedback allocation, as the mapping is inherently defined by the control channel's own structure, thereby reducing overhead while maintaining precise feedback allocation.
Data Source
AI summary
Provided is an uplink feedback channel allocation method and apparatus used to feedback data to indicate whether data packets corresponding an enhanced physical downlink control channel (E-PDCCH) were successfully decoded. A terminal may use an additional resource area of an uplink feedback channel or may use an empty resource area of the uplink feedback channel to which feedback information of a data packet corresponding to a physical downlink control channel (PDCCH) is not allocated, to perform feedback.