Boada M., Lazaro A. Battery-less NFC Sensors for the Internet of Things

Wiley-ISTE, 2022. — 177 p.The implementation of near-field communication (NFC) technology in smartphones has grown rapidly, especially due to the use of this technology as a payment system. In addition, the ability to use the energy transmitted not only for communication but also for feeding other devices, which together with the low cost of NFC chips and the internet connectivity of smartphones, allows the design of battery-less RF tags with sensing capabilities, whose information can be sent to the cloud. This is of great interest in the increasing amount of IoT (Internet of Things) scenarios.This book studies the feasibility of these sensors, analyzing the different parameters that have an influence on performance and the range of operation. It also presents techniques to increase the range and analyzes the effects of certain materials when they are close to the antenna. The design and analysis of several sensors that can be powered and read by any NFC-enabled device are presented in this work.Streamlining industrial processes has always been a priority to reduce time and, therefore, reduce costs. The identification of goods is an important factor to consider in almost any process since it is necessary to track and get specific information about them, hence the importance of automation. The most common method is to use barcode systems on a printed label with an identification number, which is read by an optical device connected to a computer.Barcodes have been included in several places of work such as libraries. They have medical uses, like in identifying blood transfusions or in the administration of medication, proving that it is an easy, fast, and accurate automatic collection method. Linear barcodes are the most common technology related to automatic identification data capture (AIDC). Usually, the reading methods use both hardware and software implementations. However, there are fully implemented methods with hardware and software solutions. Nonetheless, barcodes only contain information in one dimension (1D), containing therefore a limited amount of information. To enlarge the data representation capability, two-dimensional (2D) codes have been developed. Within the collection of 2D barcode symbologies (e.g. MaxiCode, PDF 417, code block F, Aztec), two of them are the most widespread. The first choice is the data matrix, standardized by the ISO/IEC 16022 (ISO/IEC 2000a), and the second one is the quick response (QR) codes, standardized by the ISO/IEC 18004/2000 (ISO/IEC 2000b). Data matrix capacity is 2, 334 alphanumeric characters, or 1, 556 ASCII characters, and it uses between 30% and 60 PRC less space than a QR code (Semacode 2006). However, it does not allow us to encode Japanese characters, which is the main reason why QR codes have been extended worldwide.Nowadays, smartphones are the prevailing devices with built-in digital cameras. Furthermore, the computational capability of the smartphone allows the installation of applications that read all kinds of barcode symbologies. Since QR codes are supposed to be widely used by any type of smartphone simply by taking a photo of the code, light conditions and possible damages or other alterations on the printed code must be considered as well as security issues.Wireless Power Transfer Applied to NFC.
Case Study 1: Soil Moisture Sensor.
Case Study 2: Smart Diaper.
Case Study 3: NFC Sensor for pH Monitoring.
Case Study 4: Fruit Ripeness Sensor.