A prototype of a three-axis electro-optic (EO) probe is developed that has the linearity of approximately ±0.5dB in the specific absorption rate (SAR) range of 0.01 to 100W/kg and the directivities are eight-shaped with cross-axis sensitivity isolation of greater than 30dB. It is confirmed that electric fields and SAR distributions can be measured using a three-axis EO probe.

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For robust time delay estimation, we propose a new subspace-based algorithm which estimates the phase shift not between the adjacent samples of the dechirped sinusoid but between the dechirped sinusoids in different bands. We analyze the proposed and the conventional method in AWGN channel and verifiy the proposed algorithm through Monte-carlo simulations in AWGN and multi-path channels.

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Tracking a large quantity of moving target tags simultaneously is essential for the localization and guidance of people in welfare facilities like hospitals and sanatoriums for the aged. The locating system using active RFID technology consists of a number of fixed RFID readers and tags carried by the target objects, or senior people. We compare the performances of several determination algorithms which use the power measurement of received signals emitted by the moving active RFID tags. This letter presents a study on the effect of collision in tracking large quantities of objects based on active RFID real time location system (RTLS). Traditional trilateration, fingerprinting, and well-known LANDMARC algorithm are evaluated and compared with varying number of moving tags through the SystemC-based computer simulation. From the simulation, we show the tradeoff relationship between the number of moving tags and estimation accuracy.

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