Nr.StatusDescriptionFiguresFurther Information
27 oral presentation,
completed
Scattering Bluetooth Messages between Battery-less Transponder and Mobile Telephones

This work concerns the operation of a battery-less transponder operated by intentionally generated wireless signals in the 2.4 GHz ISM band. The wireless signals consist of a power supplying data stream and special Bluetooth messages. In response, the transponder back-scatters these messages to a conventional Bluetooth receiver. Our implementation uses two regular mobile telephones, one for transmitting the wireless signals, the other for receiving the scattered signals. The back-scattering applies frequency shifting of the incident Bluetooth messages for separating transmission and receiving processes. The special Bluetooth messages include specifically designed bit sequences that by themselves serve as short Bluetooth messages that are appropriately coded for detection by the Bluetooth receiver. In effect, generation of response messages is delegated from the battery-less transponder to the transmitting telephone. Experiments show that 2 MHz frequency shifting achieves better performance and/or efficiency than 4 or 6 MHz shifting, the latter based on third harmonics. At 2 MHz, the active power consumption of the transponder is 347 μW and the wireless operational range reaches 6 cm, which is a 50% improvement over our previous work. Thus, the proposed design improves basic communication between a battery-less transponder and mobile telephones, which encourages further endeavors in this direction.


IEEE RFID-TA
Conference,
Daytona Beach, USA
2024
25 extended paper,
completed
Implementations for Scattering at 1.8 Volt between Battery-less Transponder and Mobile Telephones

Extended study for comparing advanced implementation techniques: Micro Controller Unit (MCU), FPGA (Field Programmable Gate Array), CPLD (Complex Programmable Logic Device) and ASIC (Application Specific Integrated Circuit) and for implementing a CPLD test version. Experimental results suggest that our CPLD is more suitable than MCU or FPGA implementations. The paper further demonstrates the transition from a fully synchronous to a low-power asynchronous CPLD implementation. The measured power consumption for generating the bit-stream is 87 μW, which results in a 6-fold reduction compared to our previous MCU based setup.

Research Partner: Institute for Microelectronics and Embedded Systems (IMES), Eastern Switzerland University of Applied Sciences, Rapperswil, Switzerland
Support: Innosuisse, Swiss Innovation Agency, Bern, Switzerland
IEEE Journal of
Radio Frequency
Identification,
2024
IEEE Publication
24 oral presentation,
completed
RF Harvesting for Scattering at 1.8 Volt between Battery-less Transponder and Mobile Telephones

We compare different implementation technologies for bitstream generation and subcarrier modulation: hardware, microprocessor (MCU) as well as digital and analog designs. Experiments show that the combination of MCU and switchable analog subcarrier generator shows the most promising result with an active power consumption of less than 1.2 mW with a wireless range extension to 4 cm.
IEEE RFID-TA
Conference,
Aveiro, Portugal
2023
IEEE Publication
23 project,
completed
Comparative Study Concerning Feasibility and Potential Advantages of Different Circuit Implementation Techniques

The study involves relatively low-cost measures in the area of software, alternative architectures and components in the area of discrete electronics and estimations of the power consumption of an ASIC-implemention.

Research Partner: Institute for Microelectronics and Embedded Systems (IMES), Eastern Switzerland University of Applied Sciences, Rapperswil, Switzerland
Support: Innosuisse, Swiss Innovation Agency, Bern, Switzerland
INNOSUISSE Registration
21 oral presentation,
completed
Harvesting Data Streams for Scattering between Battery-less Transponder and Mobile Telephones

WLAN signals provide a continuous data stream coexisting with BLE 5.0 advertising signals. Alternative data transfer protocols and different WLAN transmission frequencies have been studied. Results show that the User Datagram Protocol (UDP) over WLAN provides high duty cycle transmissions at an operational range of approx. 2 cm without interfering scattering.
WPW 2022
Conference,
Bordeaux, France
2022
IEEE Publication
18 oral presentation,
completed
RF Harvesting at 2.4 GHz for Scattering between Battery-less Transponder and Mobile Telephones

WLAN broadcast signals from the transmitting mobile telephone provide an additional source of energy for our battery-less transponder. An Android specific form of WLAN tethering shows the most promising potential for our scattering application based on regular, unmodified mobile telephones.
IEEE RFID-TA
Conference,
Delhi, India,
2021 (virtual)
IEEE Publication
15 oral presentation,
completed
Harvesting for Scattering Bluetooth-Signals between Battery-less Transponder and Mobile Telephones

The transmitting mobile telephone sends extended Bluetooth advertizing messages and their periodic retransmissions according to the BLE version 5.0. A specifically designed code sequence generates a quasi-continuous wave signal of approx. 2 ms duration, which provides the basis for the back-scattering process.

Support: Transport at Nanoscale Interfaces Laboratory of Swiss Federal Laboratories for Materials Science and Technology
Wireless Power Transfer Conference (WPTC),
Seoul, South Korea, 2020 (virtual)
IEEE Publication
13 oral presentation,
completed
Harvesting for Scattering Modulated RF-Signals Receivable by Mobile Telephones

A micro-controller (MCU) of a transponder is operated by using energy of RF harvesting circuit, an external 1 MHz crystal and an internal asynchronous RC oscillator for generating a frequency shift keying modulated subcarrier. The MCU consumes 9.2 mW during active operation.
Conference,
Wireless Power Week (WPW)
London, UK, 2019
IEEE Publication
10 poster presentation,
completed
Harvesting for Scattering RF-Signals receivable by Mobile Telephones

A battery-less transponder combines RF (radio frequency) harvesting and RF scattering to modulate an incident continuous wave signal such that the scattered signal is receivable by a Bluetooth Low Energy (BLE) receiver of a regular, unmodified mobile telephone.
Wireless Power Transfer Conference (WPTC)
Montreal, Canada, 2018
IEEE Publication
07 poster presentation,
completed
Energy Harvesting in EM Fields

The project involved evaluating the potential of energy harvesting in different wireless communication environments and implementing a harvesting circuit by specifically designing antenna, matching circuit and voltage multiplier. The harvested power was sufficient to operate a pocket calculator.

Project at FHO-HSR (University of Applied Sciences), Rapperswil, Switzerland with idp invent ag as project partner
05 Patents for Sale/License Transponder tag that is operable by a mobile telephone,
portable object, mobile telephone, and corresponding methods

Transponder Tag for receiving wireless signals at a frequency of a local wireless network (ISM radioband), configured to use the energy of these signals for transmitting tag information to a mobile telephone via a short-range RFID connection. This is particularly useful for numerous short distance applications, e.g. for obtaining a quick confirmation that all needed personnel belongings (keys, medical box etc.) are "on board" when leaving home/office.
01 Patents for Sale/License Method of operating an RFID-enabled mobile telephone,
mobile telephone, remote unit and application program product

RFID-enabled Mobile Telephone for quickly and conveniently checking the nearby presence of correspondingly tagged portable objects (keys, medicine box etc.), e.g. before leaving home or office, and a wristwatch for remotely controlling such a telephone