Terminal Device Carrier Aggregation Interference Control
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Solution Overview
Problem
Interference between TDD and FDD carriers in carrier aggregation systems leads to unsuitable communication performance.
Innovation Solution
A terminal device and base station apparatus that manage transmission and reception by not transmitting or receiving signals on overlapping subframes in secondary cells when different TDD UL/DL configurations are set, ensuring suitable communication control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If carrier aggregation is performed using TDD carrier and FDD carrier, then high-speed data communication is achieved, but interference between carriers increases
Solution Approach 1:
The patent extracts and removes the harmful interference by preventing simultaneous transmission/reception on overlapping subframes. The terminal device identifies overlapping subframes between TDD and FDD carriers and excludes them from transmission/reception operations, thereby eliminating the interference source while maintaining carrier aggregation benefits.
Solution Approach 2:
The patent applies preliminary action by pre-identifying and marking overlapping subframes before transmission occurs. The terminal device determines which subframes will overlap between TDD and FDD carriers in advance and prepares to avoid transmission/reception on these identified subframes, preventing interference before it occurs.
2Productivity
If simultaneous transmission and reception between TDD cells with different UL/DL configurations is enabled, then resource utilization improves, but interference and complexity increase
Solution Approach 1:
The patent segments the subframes into non-overlapping and overlapping categories. By dividing the time resources this way, the system can freely transmit/receive on non-overlapping subframes while avoiding interference on overlapping subframes, thus improving resource utilization without excessive complexity.
Solution Approach 2:
The patent applies local quality by allowing simultaneous transmission and reception in non-overlapping subframes while prohibiting it in overlapping subframes. This localized control approach enables high resource utilization where possible while avoiding interference where necessary, optimizing performance locally in different time regions.
Data Source
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AI summary
According to an aspect of the present invention, there is provided a terminal device that communicates with a base station apparatus, the terminal device including: a transmission unit that does not transmit an uplink signal in a secondary cell on the same subframe as a subframe, if the subframe in a primary cell is assumed to be a downlink subframe, in a case where multiple cells that include at least a cell in a first frame structure type (FDD) and a cell in a second frame structure type (TDD) are aggregated, different TDD UL/DL configurations are set in each of the multiple cells in the second frame structure type, and a function of performing transmission and reception at the same time between cells in the second frame structure type for which the different TDD UL/DL configurations are set is not retained.