行動通訊技術的發展，隨著使用者對頻寬無止盡的需求，朝著高速率的方向發展。因此第3代行動通訊系統發展出增強下載時傳輸速率的HSDPA技術，能夠提供10Mbps的傳輸速率，足以符合所有的多媒體服務需求。但是，為了符合高速傳輸的需要，原有細胞切換的機制也需要加強，必須提供更快速的切換。此外，隨著傳輸速率增加，系統的負載無法維持平衡，擁有較好通道品質的服務細胞，需要負擔比較大的傳輸負荷，所以細胞切換機制中，加入了負載平衡的概念。實行負載平衡，必須要由網路端統一控制，所有的細胞切換，都需要由網路端的中心控制單元決定。雖然有了負載平衡，卻犧牲了重要的切換時間。
本研究發現跨越Node B的細胞切換會發生傳輸的中斷，因此中斷時間的長短，將會大幅的影響系統可以提供的傳輸效能。因此本研究之目的在於縮短跨越Node B時的細胞切換時間，當跨越Node B的細胞切換發生時，採取傳統由行動裝置主動決定並取得傳輸通道之方法，取代由網路端主控之細胞切換機制。利用快速的頻道設定，縮短切換時之中斷時間，並且在完成切換後，觸發負載平衡機制，由網路端發起Node B內之細胞切換，因為Node B內之細胞切換不會造成傳輸中斷，所以本研究之機制完成第一階段細胞切換後可以不間斷的切換到最佳服務細胞。
本研究結果證明，當跨越Node B細胞切換發生時，縮短切換中斷時間比考量負載平衡重要，因此本研究之機制可以提升系統在細胞切換時的效能。並且本研究採用之方法符合3GPP標準文件規範，導入時，只需修正行動裝置上之切換機制，不須更動網路端之設備。

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