E-PDCCH Start Symbol Configuration for TDD Subframe 6

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In wireless communication systems, determining the starting Orthogonal Frequency Division Multiplexing (OFDM) symbol for the Enhanced Physical Downlink Control Channel (E-PDCCH) is ambiguous, affecting the blind decoding process at User Equipment (UE).

Innovation Solution

The method involves performing blind decoding on both common and UE-specific search spaces in separate Resource Blocks (RBs) of a subframe, with the first start OFDM symbol fixed at 4 and the second start OFDM symbol determined based on subframe type and higher-layer signaling, ensuring unambiguous decoding.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a single start OFDM symbol is used for both common and UE-specific search spaces, then the configuration is simple, but the decoding becomes ambiguous and unreliable

Engineering Contradiction:
Improveconfiguration complexityVSAvoiddecoding reliability
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent segments the E-PDCCH resource region into two distinct parts: common search space and UE-specific search space. Each segment is assigned a separate start OFDM symbol (first start OFDM symbol for common, second start OFDM symbol for UE-specific), allowing independent configuration and unambiguous decoding for each search space type.

Inventive Principle:
Principle #1Segmentation

2Reliability

If separate start OFDM symbols are used for common and UE-specific search spaces, then decoding reliability improves, but configuration complexity increases

Engineering Contradiction:
Improvedecoding reliabilityVSAvoidconfiguration complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies local quality by assigning different start OFDM symbol values to different regions (common vs. UE-specific search spaces) based on their specific requirements. The first start OFDM symbol is configured for common search space while the second start OFDM symbol is configured for UE-specific search space, allowing each region to have optimized properties for its function.

Inventive Principle:
Principle #3Local quality

3Adaptability or versatility

If the start OFDM symbol is determined by higher-layer signaling, then flexibility is improved, but the determination process becomes more complex

Engineering Contradiction:
Improveconfiguration flexibilityVSAvoiddetermination process complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent uses preliminary action by pre-configuring the start OFDM symbol values through higher-layer signaling before the actual E-PDCCH transmission. The first start OFDM symbol and second start OFDM symbol are determined in advance based on system configuration, reducing real-time determination complexity while maintaining flexibility.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP2784959B1Determination of epdcch starting symbol for TDD subframe 6
Publication Date: 2017.10.11 LG ELECTRONICS INC
  • EP2784959B1 patent drawingFigure 1(a)~1(b)
  • EP2784959B1 patent drawingFigure 2
  • EP2784959B1 patent drawingFigure 3

AI summary

An embodiment of the present invention relates to a method of obtaining control information through an enhanced physical downlink control channel (E-PDCCH) by a terminal in a wireless communication system. The method includes performing blind decoding on a common searching space in a set of first resource blocks on a subframe; and performing blind decoding on a terminal-specific searching space in a set of second resource blocks on the subframe, wherein a first start orthogonal frequency division multiplexing (OFDM) symbol of an E-PDCCH resource region including the common searching space in the set of first resource blocks and a second start OFDM symbol of an E-PDCCH resource region including the terminal-specific searching space in the set of second resource blocks are set individually.