高頻寬藍芽擷取點之設計與實作

Abstract

藍芽是近三年來受到廣泛注意的無線通訊技術之一，它不僅是小型裝置之間互相溝通的媒介，也是手持裝置連上網際網路的方法之一。在這篇論文裡，將會描述一個嵌入式藍芽擷取點的實作細節。在此藍芽擷取點中，採用了以ARM7TDMI為基礎的Samsung 4510B微型控制器，使用µClinux作為嵌入式作業系統，並採用開放原始碼的藍芽軟體 – BlueZ。此藍芽擷取點是依Bluetooth LAN Access Profile所設計，所有符合Bluetooth LAN Access Profile規範的裝置皆可透過此藍芽擷取點連上網際網路。 由於藍芽目前傳輸速率不高，在應用上受到許多限制，因此需要設計一個高頻寬的藍芽擷取點。在一個藍芽擷取點裡放入多個藍芽模組，是提高藍芽擷取點頻寬最直接的方法，但是藍芽模組之間互相產生的干擾，將會對系統的效能造成影響。在這篇論文裡，將會對藍芽模組間相互干擾的問題做理論上的分析，並提出兩個方法 – Bluetooth Clock Shifting Method和Specific Bluetooth Address Method來減少藍芽模組間的相互干擾。

Bluetooth is an emerging wireless technology over the past three years. It not only provides inter-connectivity between small devices, but also makes Internet connectivity for handheld devices possible. The implementation details of an embedded Bluetooth Access Point are described in this thesis. An ARM7TDMI-based microcontroller, the Samsung 4510B, is adopted in the Bluetooth Access Point, and µClinux is adopted as the embedded operating system. An open source Bluetooth stack, BlueZ, is included to provide Internet connectivity via Bluetooth LAN Access Profile. Due to the low data rate of Bluetooth, the design of a High Bandwidth Bluetooth Access Point is demanded urgently. To host multiple Bluetooth channel in a single Bluetooth Access Point is a straightforward solution, however, the inter-channel interference would affect the system throughput. A theoretical analysis of inter-channel interference of a multi-channel Bluetooth Access Point is shown in this thesis, and two methods, Bluetooth Clock Shifting Method and Specific Bluetooth Address Method, for mitigating the inter-channel interference are also proposed in this thesis.