Timing Adjustment for D-TDD Symbol Alignment
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Solution Overview
Problem
In wireless communications, especially in D-TDD networks, symbol misalignment between cells leads to significant interference, limiting the gains from dynamic time division duplexing and affecting system performance.
Innovation Solution
The solution involves defining timing adjustments for uplink and downlink timing boundaries within time domain units, allowing for alignment of symbols across different cells, thereby facilitating interference cancellation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If D-TDD technology is used to rapidly switch uplink-downlink subframes based on traffic load, then throughput of uplink-downlink services is increased, but intra-frequency cross interference between neighboring cells occurs
Solution Approach 1:
The patent applies preliminary action by pre-defining timing adjustments for uplink and downlink timing boundaries before actual transmission occurs. The network device determines and configures timing adjustment values in advance, ensuring that symbols from different cells are pre-aligned to prevent cross-interference before it happens, while still allowing dynamic TDD operation to maintain high throughput
2Adaptability or versatility
If independent uplink-downlink subframes are defined with different time domain unit structures, then service adaptability is improved, but symbol alignment between cells deteriorates
Solution Approach 1:
The patent applies parameter changes by introducing adjustable timing adjustment parameters (timing advancement or delay values) for uplink and downlink timing boundaries. These parameters can be dynamically configured based on the specific time domain unit structure being used, allowing the system to maintain symbol alignment across different service scenarios and time domain configurations while preserving service adaptability
Data Source
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AI summary
A signal transmission method and a device are disclosed. The method includes: transmitting, by a communications device, a signal based on a predefined transmission pattern. The transmission pattern defines that a non-first downlink timing boundary in a downlink time domain unit is later than or earlier than a first downlink timing boundary is defined, or that an uplink timing boundary in an uplink time domain unit is earlier than or later than the first downlink timing boundary. In this way, symbols between different cells can be located at a same location in time domain, thereby facilitating cancellation of uplink-downlink interference between the cells.