Cell Search Processing Load Reduction via Symbol Segmentation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional cell search methods in mobile communication systems require significant processing time and computing load due to the need to perform correlation calculations for all symbols in one frame, especially when detecting code groups and frame timing simultaneously.
Innovation Solution
The base station apparatus configures frames with separate pilot symbols for frame timing detection and code group detection, allowing the mobile station to perform these detections separately, reducing the computational burden by only processing code group detection symbols at specific intervals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If correlation calculations are performed for all symbols in one frame to detect code groups and frame timing simultaneously, then detection accuracy is improved, but processing time and computing load increase significantly
Solution Approach 1:
The patent divides the frame into two types of symbols: first symbols (including pilot symbols) and second symbols (including data symbols). Frame timing detection is performed only on first symbols, while code group detection is performed only on second symbols. This segmentation separates the detection tasks, allowing the mobile station to perform correlation calculations only on the necessary symbol types, thereby reducing processing time while maintaining detection accuracy.
2Measurement precision
If correlation calculations are performed for all symbols in one frame to detect code groups and frame timing simultaneously, then detection accuracy is improved, but computing load increases significantly
Solution Approach 1:
The patent segments the symbol set into first symbols and second symbols with distinct detection functions. By performing frame timing detection only on first symbols and code group detection only on second symbols, the mobile station reduces the total number of correlation calculations required, thereby decreasing computing load while maintaining detection accuracy.
Solution Approach 2:
The patent extracts the frame timing detection function from the code group detection process. By separating these functions and performing them on different symbol sets, the mobile station eliminates redundant calculations and reduces the overall computational complexity of the cell search process.
3Productivity
If separate pilot symbols are used for frame timing detection and code group detection, then processing load is reduced, but frame configuration complexity increases
Solution Approach 1:
The patent segments the frame into two distinct symbol types: first symbols (including pilot symbols) for frame timing detection and second symbols (including data symbols) for code group detection. This segmentation allows each detection function to operate independently on optimized data, improving processing efficiency while the structured frame configuration manages complexity.
Data Source
AI summary
There is provided a mobile station device capable of reducing processing of cell search. In this device, an FFT timing detection unit (603) detects a symbol timing and a frame timing detection unit (606) detects a frame timing by using the frame timing detection symbol. After a frame timing is detected, a code group detection unit (608) detects a code group and a scrambling code identification unit (610) identifies a scrambling code. That is, the frame timing detection process is separated from the code group detection process and after detecting the frame timing, a symbol timing multiplied by the code group sequence is identified so that the code group is detected only at the symbol timing.