TDD Cell Configuration for FDD Interference Avoidance
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Solution Overview
Problem
The coexistence of LTE FDD and TDD systems leads to interference between adjacent frequency bands due to out-of-band emissions, resulting in network performance degradation and waste of spectrum resources, particularly when carrier aggregation is implemented.
Innovation Solution
Configuring cells whose frequency bands interfere with FDD uplink or downlink bands as uplink or downlink cells only, respectively, to prevent interference and optimize spectrum usage, by storing and transmitting configuration information between eNB and UE, and using UL only CCs and DL only CCs during carrier aggregation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a Guard Band is arranged between FDD and TDD frequency bands to avoid adjacent-band interference, then interference between frequency bands is avoided, but spectrum resources are wasted
Solution Approach 1:
The patent extracts the interfering frequency components by configuring specific cells as uplink-only or downlink-only cells. Cells whose frequency bands can interfere with FDD uplink are configured as uplink cells only, and cells whose frequency bands can interfere with FDD downlink are configured as downlink cells only, thereby removing the harmful interference while utilizing the spectrum resources
Solution Approach 2:
The patent applies different transmission characteristics to different cells based on their frequency band characteristics. Instead of uniformly treating all cells, the system configures specific cells with uplink-only or downlink-only transmission based on their potential to interfere with FDD bands, optimizing spectrum usage locally while maintaining overall system performance
2Quantity of substance
If TDD and FDD systems work at adjacent frequency bands, then spectrum resources are utilized, but adjacent-band interference occurs affecting network performance
Solution Approach 1:
The patent segments the cell transmission functions by dividing cells into uplink-only cells, downlink-only cells, and bidirectional cells. This segmentation allows the system to prevent interference in specific frequency bands while maintaining utilization of other bands, thus achieving both spectrum resource utilization and network performance
Data Source
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AI summary
The disclosure discloses a method for providing a service from a Time Division Duplex (TDD) cell to a terminal, which includes: configuring a cell of which frequency bands can interfere a Frequency Division Duplex (FDD) uplink frequency band and a cell of which frequency bands can interfere an FDD downlink frequency band in cells provided by an eNB as an uplink cell only for transmitting uplink data and a downlink cell only for transmitting downlink data respectively on an eNB of a TDD system in advance, and storing configuration information of the uplink and downlink cells in the eNB; transmitting the configuration information of the uplink and downlink cells to a UE by the eNB; receiving, by the UE, the configuration information of the uplink and downlink cells, and transmitting data with the eNB by at least one of the uplink and downlink cells. The disclosure further discloses a system for providing a service from a TDD cell to a terminal, so as to not only avoid interference between the frequency bands of the FDD and TDD systems and implement coexistence of the FDD and TDD systems, but also fully utilize spectrum resources, ensure the high utilization rate of the spectrum resources and save resources.