無線感測網路運作的環境非常多元，有些不是很理想，例如工廠，除了複雜的遮蔽物，還可能充斥各種雜訊，容易造成訊息的錯誤率上升。要減少訊息的錯誤率，可以加大傳輸功率，但以通常以電池為電源的傳感器為了長時間運作(以年為單位)，必須盡可能節省電力。除了省電外，減少重傳也能節省頻寬。所以我們在傳感器上採用了錯誤更正碼，讓因出錯而重傳的次數降低。
錯誤更正碼有很多種，考慮到運算複雜度、耗電，以及無線感測網路遭受到的位元錯誤型態，最適合無線感測網路的錯誤更正碼是里德所羅門碼[1]。本文透過在TAROKO ZigBee傳感器，傳送端傳送經里德所羅門碼編碼的資料，接收端解碼，探討不同傳輸功率，碼長、碼率，其接收端解碼前後的封包錯誤率(PER)。

Wireless Sensor Networks works in many kinds of environments. Some of which may not be quite ideal such as factories. Not only complicated blocking stuffs but also all kinds of noise, are increasing error rate of the data we transmit. To lessen the transmit data error rate, we can increase the transmit power. However, the wireless sensor have to be energy efficient because of the long term functioning which usually in years. Besides of energy saving, the reduction in retransmission also save the network traffic. That is why we apply error correcting codes on wireless sensors to reduce the retransmission cause by errors.
There are many kinds of error correcting code. Considering computing complexity, power consuming and the error type of the wireless sensor network suffer, the best choice of error correcting code for our system is the Reed-Solomon code. In this paper, we use Taroko ZigBee wireless sensor to transmit and receive data which we encode by Reed-Solomon code before transmission and decode after reception. In the end, we observe the packet error rate (PER) before/after decoding and the error types by manipulating different transmit powers, code lengths and code rates.

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