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Sammanfattning

This report is the written part of a bachelorthesis on the computer engineering program at

University of Halmstad. The project was a cooperate project that where done together with

Free2move Holding AB. Free2move is a company with eight employees in Sweden and four in

Malaysia. The company is today developing Bluetooth modules and RFID chips. The market for

this kind of products is growing very rapidly, last year it grew 71 percent. The most important

market for Free2move is to provide other developers with Bluetooth modules.

Free2move has recieved some inquiries from previous customers about a system that would allow

communication between two or more persons. After recieving this, Free2move started to evaluate

the grounds for such a protocol and also how the transmisison time slots should be distributed

among the parties. The result was planned to manage an infinite number of users and the possibility

for two users to talk simultaneously.

The goal of the project was to develop a prototype of a reciever with functionality according to a

specification and protocol developed by Free2move. One part of the project where to do a research

of the market to find suitable hardware for the reciever, at least a tranciever/reciever and a processor

with DA-converter. Factors such as pricing, power cousumption and size should be take in

consideration during the researchphase.

Free2move had explicity said that they where intrested in a microprocessor from Texas that had low

power comsumption and that we should concider takingthat one. The PIC microprocessor from

Micrichip was one of the other candidates. Since the specification of the protocol demanded a DAconverter

with 16 bit resouliton an external codec was neccesary to be implemented in to the

construction.

During the project negotiations about the structure and functionality of the protocol where still not

finished. This resulted in a turn in what the goal of this project was, and a new goal where set. The

goal where now to develop and construct a reciever and a transmitter and make a research of how

well diffrent kind of protocol would perform.