EVM Measurement Apparatus for 5G Phase Noise Correction
Solution Overview
Problem
Current measurement standards for 5G communication systems do not adequately account for Common Phase Error (CPE) and Inter-carrier Interference (ICI) corrections when determining Error Vector Magnitude (EVM) in high-frequency and high-modulation order scenarios, leading to inaccurate assessment of transmission apparatus performance.
Innovation Solution
A measurement apparatus and method that account for CPE/ICI corrections by using Phase Tracking Reference Signals (PT-RS) and adjusting EVM requirement values based on the necessity of these corrections, allowing for appropriate determination of EVM measurement values in both high-frequency and high-modulation order conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If CPE/ICI correction is applied in reception apparatus for high-frequency and high-modulation order signals, then error rate characteristics improve, but existing measurement standards cannot accurately evaluate transmission apparatus performance
Solution Approach 1:
The patent changes the EVM requirement threshold parameter based on the modulation order. For high-modulation order schemes (64QAM, 256QAM) used in high-frequency bands where CPE/ICI correction is necessary, higher EVM thresholds are applied. This allows accurate performance evaluation that accounts for the improved error rate characteristics achieved through CPE/ICI correction while maintaining measurement precision.
2Ease of operation
If standard test standards are used for EVM measurement, then measurement simplicity is maintained, but accurate assessment of transmission apparatus performance in high-frequency scenarios is compromised
Solution Approach 1:
The patent introduces dynamic adjustment of EVM requirement thresholds based on operating conditions (frequency band and modulation order). The measurement system automatically selects appropriate thresholds: standard thresholds for low-frequency/low-modulation scenarios, and adjusted higher thresholds for high-frequency/high-modulation scenarios where CPE/ICI correction is applied. This maintains ease of operation through automated selection while improving measurement precision for different conditions.
Data Source
AI summary
An EVM measurement value is appropriately determined while CPE/ICI correction is taken into account. In a measurement apparatus (300), an EVM measurer (305) measures a modulation quality of a signal transmitted from a transmission apparatus. An EVM determiner (306) determines whether or not the measurement value of the modulation quality is equal to or less than a first requirement value, in a case where correction relating to a phase noise of the transmission apparatus is necessary in a reception apparatus. The first requirement value herein is higher than a second requirement value used in the determination of the measurement value in a case where the correction relating to the phase noise of the transmission apparatus is unnecessary in the reception apparatus.