<title>Design considerations and tradeoffs for passive RFID tags</title>

Abstract

Radio Frequency Identification (RFID) systems are widely used in a variety of tracking, security and tagging applications. Their operation in non line-of-sight environments makes them superior over similar devices such as barcode and infrared tags. RFID systems span a wide range of applications: medical history storage, dental prosthesis tracking, oil drilling pipe and concrete stress monitoring, toll ways services, animal tracking applications, etc. Passive RFID tags generate their power from the incoming signal; therefore, they do not require a power source. Accordingly, minimizing the power consumption and the implementation area are usually the main design considerations. This paper presents a complete analysis on designing a passive RFID tag. A system design methodology is introduced including the main issues and tradeoffs between different design parameters. The uplink modulation techniques used (ASK, PSK, FSK, and PWM) are illustrated showing how to choose the appropriate signaling scheme for a specific data rate, a certain distance of operation and a limited power consumption budget. An antenna system (transmitter and receiver) is proposed providing the maximum distance of operation with the transmitted power stated by FCC regulations. The backscatter modulation scheme used in the downlink is shown whether to be ASK-BM or PSK-BM and the differences between them are discussed. The key building blocks such as the charge pump, voltage reference, and the regulator used to generate the DC supply voltage from the incoming RF signal are discussed along with their design tradeoffs. A complete architecture for a passive RFID tag is provided as an example to illustrate the proposed RFID tag design methodology.

Link Budget Analysis for Backscatter-Based Passive IoT

“…On the other hand, the processor/transceiver consumes minimal power and setup communication protocols. Extensive research efforts on tag designs are ongoing as the key facilitator for passive IoT deployment from both technical and theoretical perspectives, including fundamental limits and design challenges [21], [50], [51].…”

Realizing Zones Using UPnP

“…However, the RFID capabilities can be used in new applications like automatic detection of a user or device within a given access range. For Zones detection we have designed a Zone detection mechanism in mobile devices using triggering method in RFID Tag [4]. Figure 2 depicts the Zone detection setup at the entry and exit points of a Zone.…”

Radio Transmission Performance of EPCglobal Gen-2 RFID System

“…The transmission rate (or link frequency (LF)) varies depending on the parameters sent by the reader to the tag and on the encoding type used. The range of LF is given as following; 5 640 kbps LF kbps ≤ ≤ (2) Data are transmitted at the lowest data rate of 5 kbps when we use Miller code with M = 8, TRcal = 200 μs and DR = 8 (where M=2k is the symbol size, k is the number of bits and DR is the divide ratio and takes on one of two values; namely 64/3 and 8). The maximum data rate of 640 kbps can be achieved using FM0 encoding, TRcal = 33.3 μs and DR = 64/3.…”