2.45 GHz天線分集射頻定向系統之實現

Implementation of 2.45 GHz Radio Direction Finding with Antenna Diversity

杜明德(Ming-De Du)

指導教授 ： 余政杰

國立臺北科技大學/電資學院/電腦與通訊研究所/碩士(2011年)

https://doi.org/10.6841/NTUT.2011.00269

摘要

本射頻定向研究使用FlexiPanel公司生產之EasyBee射頻收發模組，射頻收發模組符合無線網路IEEE 802.15.4 標準與ZigBee 通訊協定之媒體存取層與實體層的規範，其內部射頻收發積體電路為TI公司之CC2420 RFIC。
本論文研究共分二個階段，第一階段為在數據通訊中建立基本溝通介面，結合微控器與射頻收發模組完成雙向無線傳輸，第二階段為整合微控器、射頻收發模組、天線開關（ASM）及天線使系統更具完整性。
在數據通訊部份經由PIC18LF4620微控器之串列週邊介面設定射頻收發模組，並使用組合語言撰寫讓系統之功能俱備便利性與實用性，再將微控器與射頻收發模組完成雙向無線傳輸，達到master端與slave端都具有發射與接收功能。
在無線通訊中必須達到定向、搜尋的能力，本論文在雙向無線傳輸部分，將指向性天線及全向性天線接上1對2 天線開關（ASM）取代Master端原始射頻收發模組上的全向性天線，經由控制RF Switch可以有效的切換兩隻天線，透過射頻收發模組之接收信號強度判別功能與距離相對關係，可以正確的尋找Slave端，構建完整定向系統及功能，達到物品搜尋的功能。

關鍵字

射頻定向 ； 射頻收發模組 ； IEEE 802.15.4標準 ； ZigBee通訊協定 ； 天線開關 ； 串列週邊介面 ； 全向性天線 ； 指向性天線 ； 接收訊號強度 ； 微控器

並列摘要

In this thesis, a research is conducted to build a complete Radio Directional Finding (RDF) system. Omni-directional/Directional antennas, Antenna Switch Module (ASM), PIC18LF4620 microcontroller and EasyBee RF transceiver module were all utilized to implement the entire RDF system. The IC (CC2420) embedded in the EasyBee RF transceiver module is equipped with the ability to dynamically update the content of the built-in Received Signal Strength Indicator (RSSI), which enhances the performance of the RDF system. In the system, The ZigBee-ready EasyBee RF manufactured by FlexiPanel is IEEE 802.15.4-compliant.
This research is divided into two stages. In the first stage, the data communications are properly set through the 4-wire Serial Peripheral Interfaces（SPI）by microcontrollers to ensure proper functioning of the entire two-way digital RF transceiving system; in the second stage, the RDF system is completed by the integration of PIC18LF4620 microcontrollers, antennas, ASM and EasyBee RF transceiver module.
In order to enhance a complete functional system, the research conducted in this thesis integrated not only hardware but also firmware. Moreover, the Microchip PIC18LF4620 microcontroller and its 75 PIC18 core assembly instructions are adopted to provide a simplified system architecture. Lastly, the communication reliability and range are tested in various open sites, which further validate the application in everyday environment.

並列關鍵字

Omnidirectional Antenna ； Directional Antenna ； Radio Direction Finding ； Radio Transceiver ； Received Signal Strength Indicator ； IEEE 802.15.4 Standard ； Microcontroller ； Serial Peripheral Interface.

參考文獻

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