在本論文中,我們在ZIGBEE(CC2430 晶片)的平台上加入LDPC CODE 的編 解碼,以改善ZIGBEE 無線傳輸的錯誤率。ZIGBEE 無線技術是目前在短距離無 線傳輸上較受歡迎的一種新技術,它有著低成本、低耗電、體積小、容易佈置等 優點。 ZIGBEE[4]所傳輸的資料,大部份是以控制信號、感測資料為主,這一類型 的資料所需要的頻寬較少,也就是資料傳輸量比較小,但是它的重要性卻很高, 這樣的資料若是有錯誤發生,所帶來的影響很大。因此在一定的頻寬下,我們可 以利用這樣的空間來改善它的錯誤率,在每次的傳輸中加入錯誤更正碼,雖然這 樣會增加它傳輸資料量,但是它所帶來的好處是傳輸時的正確性會提高,減少錯 誤的發生。 LDPC CODE[2]是近年來比較受歡迎的一種錯誤更正碼,因為它的效能非常 接近Shannon Limit,解碼器簡單且硬體成本低,跟目前最常使用的TURBO CODE 來比較,效能以及製作複雜度都是LDPC 比較好,而DVB-S2 也決議以LDPC CODE 來取代TURBO CODE。在整個實作系統裡,我們先由PC 端做錄音來產 生MP3 聲音資料,接著透過ZIGBEE 來做傳送,而在接收端PC 做聲音的播放, 由此比較所改善的效果。
In this paper, we implement LDPC CODE in ZIGBEE (CC2430 chip) platform to improve the error rate. In the short-range wireless transmission technology, ZIGBEE is a popular new technology. Its advantages are low cost, low power, small size, easy to structure, etc. Control signal, sensing data is mainly transmitted data in ZIGBEE. This type of information required less bandwidth. It means that data transfer is relatively small, but its importance is very high. Such information, if an error occurs, it will have a serious impact. Therefore, a fixed bandwidth, we can use this space to improve its error rate. Add error correction code to each transmission data. Although this will increase the amount of data transferred, but its advantage is that accuracy will improve. In this paper, we added the LDPC CODE to improve the error rate. LDPC CODE is an error correction code. It is more popular in recent years, because its performance is very close to the Shannon Limit. The hardware decoder is simple and low cost. It is relatively good on the performance and complexity. In the implementation system, we produce MP3 data by recording, and then send data through ZIGBEE. At the receiving PC side, when get all data then will play MP3 music. Comparison of the effect of this improvement.