Periodic Reporting for period 3 - SCATTERERID (Analysis and synthesis of wideband scattered signals from finite-size targets – aspect-independent RF analog footprint)
Berichtszeitraum: 2021-09-01 bis 2023-02-28
The need for information identification and capture is a matter of prime importance in modern societies. Every sector of society relies on the identification of data exchanged, the updating of the data recorded on a tag and the measurement of physical parameters. Key issues such as the way to reduce power consumption, to improve the communication quality-of-service and to enhance connectivity have recently come up for lots of industries. One important direction for researchers to consider is to develop battery-less, low cost tags for wireless identification and sensing. Lots of improvements have been done in the past few years on communication systems, based on electronic devices where an integrated circuit is at the heart of the whole system. The democratization of these chip-based systems, like the radiofrequency identification (RFID) one, will give rise to environmental issues in the future. However, these improvements pave the way for the development of new concepts based on radar or reflectometry principles. The main goal of this project is to develop a new generation of systems based on chipless radiofrequency (RF) labels, operating like radar targets, and compatible with new functionalities. ScattererID project aims at introducing the paradigm of RF communication system based on chipless label, that is to say tags without any chip, bringing an ID, able to communicate with radio waves, having extremely low costs and where other useful functionalities can be added. With comparable costs to a barcode, these labels should stand out by providing more functionalities than the optical approach. Thus, this research project aims to carry on Etienne Perret’s work begun on chipless at the LCIS laboratory with the objective to show that it is possible to associate the chipless label ID with other features like the ability to: 1) write and rewrite the information (ID), and 2) associate an ID with a sensor function, 3) associate an ID with gesture recognition. These advances are primarily based on important technological breakthroughs. From a theoretical point of view, to our knowledge, too few works have focused on the accurate understanding of the physical phenomena involved in both cases, particularly those linked with the phenomena that occurred at the Nano scale (1- Nano switches | 2- sensors based on nanowires) and the modification of the RF waves characteristics that interact at the macroscopic scale and contain the useful information. For instance, the possibility of designing reconfigurable and low cost (i.e. printable) tags involves the development of original approaches at the forefront of progress, like the use of CBRAM from microelectronics, allowing to achieve reconfigurable elements based on Nano-switches. From a practical point of view, the ultimate goal is to demonstrate that the chipless RFID has the greatest assets to compete with the barcode and succeed in leadership positions in some practical applications. The development of a new easy-to-use and low-cost technology that would allow the "objects" to communicate for traceability means is eagerly awaited. This project is very promising for Europe: the need for a new market for printer companies and the pulp and paper industry is already shown by the quick development of inkjet printing of conductive materials. Tomorrow, most people will have bought conductive ink cartridges, already compatible with their own inkjet printer to print conductive patterns on sheets of paper. In that context “smart packaging” is a significant target for these companies and everything has to be done.
Significant work has been done on RF Switches (WP1), Robust tags (WP2) and “Gesture Recognition” (WP3).In WP1, totally imprinted CBRAM RF switches have been achieved using transfer printing techniques. We are now able to control the resistance of these switches by controlling the tension/current applied to the CBRAM cell. In WP2, we have introduced a totally planar resonant scatterer with roll invariant cross polarization.For WP3, a chipless RFID label with identification and touch sensing capabilities has been introduced.
- A novel methodology for achieving a variable resistance for CBRAM cells for microwave applications has been introduced.
- Electronically rewritable chipless RFID tags have been designed, fabricated through thermal transfer printing on flexible PET substrates and characterized.
- A smart and robust chipless RFID label with identification and touch sensing capabilities has been developed.
- We have shown that contactless characterization of thermal expansion coefficient (CTE) of metals can be realized based on free-space RF measurements. This concept has also been used to convert chipless tags to temperature and humidity sensors.
- We have introduced a new RF approach to Wirelessly Detect Surface Modification of Silicon Nanowires. We have seen the possibility to detect the presence of grafted molecules on the surface of silicon nanowires with a wireless RF radar approach based on the measurement of the backscattered signal of a resonant structure on which the nanowires are deposited.
- We have work on the idea of “Optimal Angle in Bistatic Measurement for Chipless Tag Detection Improvement”. We have shown that the use of a bistatic reading configuration by optimizing the angle between the two antennas can enhance the reading performance of the chipless tag for short-range applications.
- A significant work has been done on a new topic about “Motion-Modulated Chipless RFID”. Motion-modulated chipless RFID is presented as an effective backscatter communication method for identification and sensing of moving objects at large distances.
We have introduced the concept of “Directional amplitude backscatter modulation with suppressed Doppler based on rotating resonant Loop”. The presented backscattering modulation technique provides an amplitude modulating waveform which is uniquely linked to the directional reradiation pattern of the rotating loop scatterer in a definite resonant mode.
A test bench has been built and automated to perform chipless tag characterization. It is now possible to measure the RCS of objects in 3D.
- A novel methodology for achieving a variable resistance for CBRAM cells for microwave applications has been introduced.
- Electronically rewritable chipless RFID tags have been designed, fabricated through thermal transfer printing on flexible PET substrates and characterized.
- A smart and robust chipless RFID label with identification and touch sensing capabilities has been developed.
- We have shown that contactless characterization of thermal expansion coefficient (CTE) of metals can be realized based on free-space RF measurements. This concept has also been used to convert chipless tags to temperature and humidity sensors.
- We have introduced a new RF approach to Wirelessly Detect Surface Modification of Silicon Nanowires. We have seen the possibility to detect the presence of grafted molecules on the surface of silicon nanowires with a wireless RF radar approach based on the measurement of the backscattered signal of a resonant structure on which the nanowires are deposited.
- We have work on the idea of “Optimal Angle in Bistatic Measurement for Chipless Tag Detection Improvement”. We have shown that the use of a bistatic reading configuration by optimizing the angle between the two antennas can enhance the reading performance of the chipless tag for short-range applications.
- A significant work has been done on a new topic about “Motion-Modulated Chipless RFID”. Motion-modulated chipless RFID is presented as an effective backscatter communication method for identification and sensing of moving objects at large distances.
We have introduced the concept of “Directional amplitude backscatter modulation with suppressed Doppler based on rotating resonant Loop”. The presented backscattering modulation technique provides an amplitude modulating waveform which is uniquely linked to the directional reradiation pattern of the rotating loop scatterer in a definite resonant mode.
A test bench has been built and automated to perform chipless tag characterization. It is now possible to measure the RCS of objects in 3D.
Important work is in progress, in particular the fact that we can significantly increase the coding capacity with RF imaging type reading. We have been able to show that it is quite realistic to obtain the 60-bit bar that was given as an objective in the initial project. This reading mode is interesting insofar as it is compatible with the reading of tags that are very close to each other.
As regards the topic of modulation by motion, the expected results are also very important for achieving the objectives of task 5. We will be able to show in very concrete applications the increase in reading distance (factor 30) as well as the use of this principle to monitor sensor information (application to measure breathing, vibration frequency, etc.). Ongoing work has shown that it is possible to significantly increase the DeltaRCS and therefore the reading distance by modifying the topology of the chipless tag. This reading topic was introduced during the project, so we are the first team to work on it and will publish several articles which we hope will become reference articles on the subject.
Expected results until the end of the project are still the ones described in the Annex 1 to the Grant Agreement (Description of the Action).
As regards the topic of modulation by motion, the expected results are also very important for achieving the objectives of task 5. We will be able to show in very concrete applications the increase in reading distance (factor 30) as well as the use of this principle to monitor sensor information (application to measure breathing, vibration frequency, etc.). Ongoing work has shown that it is possible to significantly increase the DeltaRCS and therefore the reading distance by modifying the topology of the chipless tag. This reading topic was introduced during the project, so we are the first team to work on it and will publish several articles which we hope will become reference articles on the subject.
Expected results until the end of the project are still the ones described in the Annex 1 to the Grant Agreement (Description of the Action).