Efficient Authentication Protocol and Its Application in Resonant Inductive Coupling Wireless Power Transfer Systems

Chaos theory and its extension into cryptography has generated significant applications in industrial mixing, pulse width modulation and in electric compaction. Likewise, it has merited applications in authentication mechanisms for wireless power transfer systems. Wireless power transfer (WPT) via resonant inductive coupling mechanism enables the charging of electronic devices devoid of cords and wires. In practice, the key to certified charging requires the use of an authentication protocol between a transmitter (charger) and receiver (smartphone/some device). Via the protocol, a safe level and appropriate charging power can be harvested from a charger. Devoid of an efficient authentication protocol, a malicious charger may fry the circuit board of a receiver or cause a permanent damage to the device. In this regard, we first propose a chaos-based key exchange authentication protocol and analyze its robustness in terms of security and computational performance. Secondly, we theoretically demonstrate how the protocol can be applied to WPT systems for the purposes of charger to receiver authentication. Finally, we present insightful research problems that are relevant for future research in this paradigm.

Radiation damping strongly perturbs remote resonances in presence of homo-nuclear mixing sequences

In this work, it is experimentally shown that the weak oscillating magnetic field (known as the “radiation damping” field) caused by the inductive coupling between the transverse magnetization of nuclei and the radio frequency circuit perturbs remote resonances when homo-nuclear total correlation mixing sequences are applied. Numerical simulations are used to rationalize this effect.

Galvanic Phase Coupling of Superconducting Flux Qubits

We investigate the galvanic coupling schemes of superconducting flux qubits. From the fundamental boundary conditions, we obtain the effective potential of the coupled system of two or three flux qubits to provide the exact Lagrangian of the system. While usually the two-qubit gate has been investigated approximately, in this study we derive the exact inductive coupling strength between two flux qubits coupled directly and coupled through a connecting central loop. We observe that the inductive coupling strength needs to be included exactly to satisfy the criteria of fault-tolerant quantum computing.

Two-Probe Setup with Improved Calibration for Online Impedance Measurement of Electrical Assets

<p>The online impedance serves as one of the most crucial specification to evaluate the health status and efficiency of an electrical device or system. The inductive coupling technique is a preferred approach to measure the online impedance due to the ease of implementation of the circuit which has zero physical contact to the live electrical system. The existing inductive coupling method deployed to measure the online impedance of an electrical device under test (DUT) adopts two probes in total: an injecting inductive probe (IIP) and a receiving inductive probe (RIP). An open/short/load (OSL) calibration procedure is implemented to eradicate the ramifications of the probe-to-probe coupling, however, based on the assumption that the calibration criterions (shorted, open and 50Ω) are approximated to their theoretical values in a specified frequency range. Hence, any measurement with frequency outside the specified range (i.e. larger than 1 MHz) will not be accurate due to the frequency-dependent residual inductances and capacitances of the calibration model. To overcome the aforesaid limitation, this paper introduces an improved calibration procedure which is applicable for a wider frequency range which takes the frequency-dependent characteristics into consideration. With the two-probe measurement setup (TPMS), the adopted improved calibration procedure is introduced to eradicate the ramifications of the probe-to-probe coupling with the intention to refine the accuracy of the extracted online impedance.<a></a></p><p></p>

Two-Probe Setup with Improved Calibration for Online Impedance Measurement of Electrical Assets

<p>The online impedance serves as one of the most crucial specification to evaluate the health status and efficiency of an electrical device or system. The inductive coupling technique is a preferred approach to measure the online impedance due to the ease of implementation of the circuit which has zero physical contact to the live electrical system. The existing inductive coupling method deployed to measure the online impedance of an electrical device under test (DUT) adopts two probes in total: an injecting inductive probe (IIP) and a receiving inductive probe (RIP). An open/short/load (OSL) calibration procedure is implemented to eradicate the ramifications of the probe-to-probe coupling, however, based on the assumption that the calibration criterions (shorted, open and 50Ω) are approximated to their theoretical values in a specified frequency range. Hence, any measurement with frequency outside the specified range (i.e. larger than 1 MHz) will not be accurate due to the frequency-dependent residual inductances and capacitances of the calibration model. To overcome the aforesaid limitation, this paper introduces an improved calibration procedure which is applicable for a wider frequency range which takes the frequency-dependent characteristics into consideration. With the two-probe measurement setup (TPMS), the adopted improved calibration procedure is introduced to eradicate the ramifications of the probe-to-probe coupling with the intention to refine the accuracy of the extracted online impedance.<a></a></p><p></p>