應用無線射頻技術於農業環境定位系統之研究

Study on A Positioning System for Radio-Frequency Technology in Agricultural Environment

許統揚(Tong-Young Hsu) ； 王介鼎(Chieh-Ting Wang) ； 盛中德(Chung-Teh Sheng)

《農林學報》 62卷4期 (2013/12) Pp. 305-318

https://doi.org/10.30089/JAF.201312_62(4).0002

摘要

無人自走施藥車之開發，首先必須發展適用的定位系統，以獲得車輛在導引過程中之精確座標。而定位系統大致可區分為慣性定位（IPS）、全球定位（GPS）、區域定位系統（LPS）與環境偵測定位系統（EDS）等四大部分，上述系統可互相搭配運用。為了能符合本國之戶外農業環境，本研究應用區域性定位系統之窄頻無線電波的超高頻（UHF）電訊方式，在限定區域範圍內對標的物進行測距與定位。本研究使用nanoPAN 5375 RF模組，自行開發一符合區域性適合農業環境之射頻定位系統，利用對稱雙邊雙向測距法（SDS-TWR）求得測距值，以航行時間定位法（ToF）與多點基地台選擇策略法（MBSST）求得最佳群組之估測座標值，並以Visual Basic 2008程式語言撰寫定位系統程式。實驗結果，在面積500 平方公尺內訊號受到遮蔽效應情況之非視線傳播（N-LOS）環境下，定位精度可維持為公分級誤差。

關鍵字

無線射頻 ； 區域定位 ； 農業環境定位

並列摘要

To Develop an automatic spraying vehicle, it has to develop an appropriate positioning systems for obtain a precise coordinates in the guidance process first. The positioning systems can be broadly divided into 4 categories, including the Inertial Positioning System (IPS), Global Positioning System (GPS), Location Positioning System (LPS) and Environmental Detection System (EDS). In order to comply with the outdoor agri-environment in Taiwan, the narrow band radio waves UHF technology of the LPS applied in this study, within the limited range of subject matter area for ranging and positioning. This study applied the nanoPAN 5375 RF modules, developed a RF positioning systems in the outdoor agri-environment, the use of SDS-TWR method obtained the ranging values, the use of ToF method and the Multi-Base Station Selection Tactics (MBSST) method obtained the best estimating coordinate values of the groups. The program was derived with Visual Basic 2008. The results of this study shown that, positioning precision can be maintained within the centimeter level in the area 500 m2 in the no-line of sight (N-LOS) environment.

並列關鍵字

Radio frequency (RF) ； Location positioning ； Agri-environment positioning