IEEE 802.15.4 MAC-Layer Implementation for Wireless Sensor Networks
|Supervisor:||Horst Hellbrück , Torsten Teubler|
Sensor networks are networked, small computers that are equipped with sensors and thus perceive their environment. Sensor networks and their application are already well studied many years. A new trend in sensor network research is the question how to connect them to the Internet. Here first steps are already done but there is still much potential for research. For a generic approach we need a device to connect sensor nodes to a PC acting as an Internet gateway. One proposed MAC Layer protocol in sensor networks is IEEE 802.15.4. The IEEE 802.15.4 protocol is not supported natively by common operating systems. One approach is to directly implement it within the firmware of wireless devices attached to the PC. However, we take a different approach and implement most of the protocol handling on the PC side in Java.
The hardware foreseen for this thesis is the Atmel Raven USB Stick. Atmel provides a lot of software for that device. One is the “Radio Evaluation Software” (RES) for the evaluation of the RF230 radio chip. The Raven-Stick is thereby recognized by Windows, Linux or Mac OSX as a serial interface (COM interface). With a terminal client (e.g. putty) you can connect to this serial interface and send ASCII characters which are transmitted via the radio chip. We already extended the RES Firmware for the stick enabling the Atmel Raven USB Stick to send frames of maximum IEEE 802.15.4 size. We already developed a small Java library for encapsulating basic send and receive functions. In this work the functionality of the Raven Stick Firmware and the Java Raven Stick library has to be extended further so that all built-in IEEE 802.15.4 functions of the RF 230 chip on the Raven Stick can be controlled via the Java library. Additionally, on top of the Raven Stick library a protocol layer is to be developed and implemented. This layer handles all IEEE 802.15.4 (CSMA-Mode) protocol features. The correctness and functionality can be evaluated with Wireshark which identifies and dissects IEEE 802.15.4 frames.
- Extension of the firmware for the Raven-Stick.
- A “terminal” (user ASCII input via a terminal client like putty) and a binary mode for configuration and raw frame sending and receiving.
- Extension of Java library that encapsulates the basic functions of the Raven Stick (Raven Stick Driver).
- Develop a Java Protocol Layer on top of the Raven Stick Driver implementing the IEEE 802.15.4 protocol in CSMA-Mode.
- Very good skills in problem-abstraction
- Good knowledge of Java programming
- Good knowledge of microcontroller programming with Atmel microcontrollers
- Good self-organized working skills
- Good knowledge of the English language