在本論文中，我們研究考量匯流排的全域繞線問題。如果一個繞線器對一個有匯流排的設計做繞線而不考慮匯流排的長度匹配問題，它的結果會對匯流排造成更差的時序不匹配。因此，透過修改一個知名的全域繞線器NTHU-Route 2.0，我們提出一個考慮匯流排的全域繞線器使其可以考量匯流排的長度匹配問題，其特點包括: (1) 一個新的決定拆除重繞順序的方法，(2) 一個長度限制的混合單向單調繞線方法。
從實驗結果可得知，我們的繞線器可以成功的解決11個測試電路中的9個使其無溢出狀況產生，這9個測試電路中有一個電路NTHU-Route 2.0無法完全消除其總溢出數。除此之外，我們的全域繞線器可以在保持相當的總繞線長度和執行效率的同時，對於匯流排繞線長度總偏差可以得到一個高品值的繞線結果。

In this thesis, we study a global routing problem that considers buses. If a router routes a design that contains buses without considering the length-matching issue of buses, the result may cause worse timing mismatch for a bus. To tackle this problem, we present a bus-aware global router that handles the length-matching issue of buses by modifying a well-known global router, NTHU-Route 2.0, with the following enhancements: (1) a new net ordering determination method for rip-up and reroute, and (2) a length-bounded hybrid unilateral monotonic routing method.

The experimental results show that our router can successfully solve 9 of 11 benchmarks without causing any overflow. In particular, for one of the 9 benchmarks, NTHU-Route 2.0 cannot completely eliminate its total overflow. In addition, our global router can produce a high quality solution in terms of total bus wirelength deviation, while maintaining comparable total wirelength and runtime efficiency.

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