智慧型射頻辨識感測器標籤設計與使用射頻辨識技術作定位

Abstract

本文主要分為兩大部分，第一部分為設計智慧型射頻辨識感測晶片，第二部分為整合射頻辨識定位系統。 所設計的晶片結合CMOS射頻電路與以CMOS微機電(MEMS)技術所製作的陀螺儀感測器(Gyroscope sensor)，以達到單一晶片目的。陀螺儀感測器主要用以量測加速度、角加速度等物理量。為達到省電的機制，本文中的射頻電路，被設計為半主動式標籤，即射頻辨識標籤上有電源裝置，平常標籤是處於休眠狀態，當標籤接近讀取器時，會讓標籤上的電源開關導通，喚醒標籤，此時再由標籤上的電源提供感測器所需的能量，再將感測值傳給讀取器。此半主動架構較主動式架構省電、而且傳輸距離也較被動式架構來的遠。 本研究利用射頻辨識技術，建構了一個定位感測系統。首先，一個智慧型的射頻標籤感測模組被實現，並透過實驗結果推導出無線射頻感測模組的不確定性模型(Uncertainty Model)。本研究利用模組上的RSSI(receive signal strength indicator)功能，量測出距離的估測值，並利用機率的方法，去推論追蹤目標的位置機率分布。在此，射頻感測模組搭配了陀螺儀感測器，可以用來驗證所設計的晶片架構。並且透過射頻訊號，可將感測值傳送到遠端系統作處理。本研究的定位感測系統可應用在行動機器人的定位或獨居老人的監控系統。 在射頻電路部分主要以TSMC(台積電) 0.18um製程製作。而定位系統則以Chipcon公司的cc2500射頻模組、結合8051單晶片及陀螺儀感測器去實現。

This thesis mainly consists of two parts. First part is the design of Smart RFID sensor chip. Second is the integration of RFID localization systems. The chip combines the CMOS RF circuit with the gyroscope sensor, which is manufactured with CMOS MEMS to provide the smart RFID sensor of a single chip. The gyroscope sensor is used for measuring physical quantity of linear and angular acceleration. In order to achieve the power-saving objective, the RF circuit is designed with the semi-active tag, that is, a power source is built in the RFID tag which is normally suspended. In addition, the tag is activated by RF signal only when it approaches a reader. The semi-active tag has lower power consumption than active tag, and longer distance than passive tag. In this research, a localization sensing system with RFID technology is constructed. First, a smart RFID sensor module is developed and obtained an uncertainty model of the sensor module through experiments. Then, this research utilizes RSSI function of the module to get the measurement of distance and estimate the position of target tag using a probabilistic methodology. The module equipped with a gyroscope sensor can demonstrate the architecture of our chip. Through RF signals, the data are delivered to remote systems. Further, this research can apply the system on robot localization and monitoring systems of solitaries. The RF circuit is manufactured by TSMC CMOS 0.18um process. The RFID localization system is realized using the cc2500 RF module by Chipcon, 8051 microcontroller, and the gyroscope sensor.