應用六標準差設計DMADV手法改善WiFi產品重測率

Using Design for Six Sigma DMADV Methodology to Improve Retest Rate of WiFi Product

方爾寧(Fang, Erh Ning)

指導教授 ： 蘇朝墩

國立清華大學/工學院/工業工程與工程管理學系碩士在職專班/碩士(2015年)

摘要

網通產業在製造過程中為因應顧客與市場需求，WIFI產品於出貨前(Final test)需檢測產品，確認訊號接收與傳送上是否符合市場規格要求。在產能日益增加情況下，生產線測試站擴增，導致產品經過測試站所發出無線訊號互相干擾，造成測試數據不穩定，導致良率降低；進一步分析測試不良產品，其大都屬於在測試過程中訊號干擾而影響測試品質，並非產品實際不良問題。重新測試後約90%以上產品經由重測後則會轉為良品，此現象因產線中大量產品重覆測試與彼此干擾，造成產能下降與人工時間成本的浪費。
本研究運用六標準差設計DMADV架構展開，由內外部顧客聲音使用QFD歸納設計規格，經由GRR分析測試站量測變異，確認影響測試站的變異因子；利用TRIZ概念發想設計天線治具結構，並使用田口方法計確認改善方案之穩健性，藉由控制訊號發射路徑，減少多重信號干擾情況，使測試站重測率由改善前14.01%降至改善後4.05%。最後經由pilot run導入改善方案驗証專案達標，並由財務效益估算約可減少一年一千萬以上測試成本。

關鍵字

六標準差設計 ； 雜訊干擾 ； 網路通訊

並列摘要

Nowadays, in order to meet the requirement from different customers and to confirm functions of their product, network corporation usually do many test before shipping. To gain more profit, they setup more and more test stations to increase production capacity but lead to unstable test result and low yield rate. We further do some analysis to the defective products and find out the problem that is caused not by quality of the products but signal interference in test stations. More than ninety percent of retest products is good product. This may lead to lots of product retest procedure, low production capacity and time cost.
In the thesis, we propose a method to lower the retest rate of Wi-Fi product by using six sigma DMADV structure. Firstly, we use QFD (Quality Function Deployment) table to convert voice of customer to design the product specification. Secondly, we use GRR (Gauge Repeatability and Reproducibility) to analyze measurement variation of each test station and to check the key factor of test station. Thirdly, we use TRIZ (Theory of Inventive Problem Solving) theory to activate the concept for designing test station. Fourthly, we use Taguchi Methods to refine the robustness of our method. In this way, we can control the WiFi signal path consistency and reduce multi-path interference. Finally, to verify the method, we do a pilot run. After analyze the report, this method can lower about 10% retest rate and to save test cost by at least 10 million dollars per year.

並列關鍵字

Six Sigma ； DMADV ； Multi-path Interference ； Network Communication

參考文獻

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