Academic literature on the topic 'Active load modulation'

<span>The proposed scheme has considered a three-phase four-wire system, which experienced sag and swell in source voltage for a certain period while feeding an unbalanced and variable non-linear load. The load has unequal resistive and reactive elements in the three phases, forming the unbalanced component. A three-phase silicon controlled rectifier converter with adjustable firing angle connected to the load has formed the variable non-linear component. This has been considered, so as to simulate the unbalanced and variable non-linear nature of loads in real-time power system. The trends in the total harmonic distortion variation were obtained for the proposed system under power factor correction and voltage regulation mode operation when the load-side converter firing angles of 30°, 60° and 90° were considered using MATLAB/SIMULINK software. Three pulse-width-modulation methods, namely, sinusoidal pulse-width-modulation, space vector modulation and hysteresis pulse-width-modulation have been used to generate pulses for the voltage source converter of the shunt active filter based on the reference currents generated using synchronous reference frame theory. It has been demonstrated in the proposed paper that power factor correction, voltage regulation, better harmonic reduction and hence load compensation are obtained simultaneously by using two SAFs.</span><br />

The paper covers one of the communication technologies used in wireless sensor networks. We have presented improvements in existing radio frequency identification (RFID) systems to address the problem of the phase selection in active load modulation (ALM). The phase selection affects the interoperability of communication devices and has to be addressed in the design phase of a new tag. A novel transmission method is presented to make the phase selection irrelevant for device interoperability. A second solution is shown to improve the existing system synchronization, which allows operation with arbitrary selected phase. A mathematical analysis of signals present on the antenna was used together with the reference reader model to perform an analysis of proposed improvements. We proved that the proposed transmission method is less affected by phase selection. Furthermore, we demonstrated that existing system improvement allows synchronization and operation at an arbitrarily selected phase despite the continuous transmission and large signal-to-interference ratio.