The Study Of The Bluetooth Protocol Stack And Its Implementation In C Language

Bluetooth is a technology developed for short-range wireless communication by Bluetooth Special Interest Group (SIG). The purpose of Bluetooth technology is to replace the cable and connect various devices such as cell phone, PC and PDA together by electromagnetic wave. Bluetooth uses the same 2.4GHZ frequency band as 802.1 Ib does for wireless communication. Because Bluetooth technology is mainly for mobile terminal devices powered with low capacity batteries, the transmission speed must be limited to reduce the power consumption. It can now support the transmission speed of IMbps for data and voice communications within 10 meters. The Bluetooth Specification developed by SIG defines rules for implementing Bluetooth in almost all the aspects. It includes two parts: Core Specification and Profile.In the thesis, I expatiate on the core and important parts of the Bluetooth Specification. The problems encountered on the process of design and implementation is discussed. Based on Ericsson Bluetooth module ROK 101 007, I have implemented four core protocol layers (HCI, L2CAP, SDP, RFCOMM) and two profiles (LAP, DUNP), in C language under Linux. I explain each protocol layer associated with the written code, and give the data flow of the implemented protocol at the end of each chapter.In the experiment, I have realized the data transmission successfully between two PCs in high speed by using Ericsson Bluetooth module and the implemented protocol stack. What is more, I have implemented two profiles (LAP and DUNP) that enable one PC to access LAN or dial up Internet wirelessly by making another PC as access point, which is connected to LAN or Modem as usual.