N-continuous orthogonal frequency division multiplexing is a precoding technique that achieves a lower-sidelobe transmission signal. However, the precoding method requires a wide dynamic range arithmetic. This study proposes a novel decomposition of the precoder matrix of N-continuous OFDM for a low-end field-programmable gate array (FPGA) without DSP blocks. Results of numerical experiments and a test design confirm that the singular value decomposition is suitable for FPGA implementation.

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Auto-tuning proportional-integral-derivative (PID) controller improves the dynamic response of a switching converter. In this paper, a robust H∞ synthesis approach is proposed to design an auto-tunable PID controller for buck converters. Through the proposed H∞ approach, the PID controller is parameterized by a tunable parameter behaving like a ‘knob’ on the closed-loop performance. Simulations show the closed-loop characteristics. Practical experiments confirm the dynamic response improvement, with a comparison of a parameter fixed PID controller by zero-pole placement.

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This paper presents a compact planar multiband antenna designed for mobile communication systems. With increasing miniaturization of communication systems and electronic components, the need for compact and small-size antennas is widely perceived. To accomplish this, a right angled isosceles triangular Microstrip patch antenna is designed using CST Microwave studio software. The proposed antenna is designed to be operated at UWB frequency range with coaxial feed technique. The antenna design has been used for size reduction as well as bandwidth improvement. Furthermore, basic antenna parameters such as resonant frequency and the quality factors for dominant modes have been analyzed and compared.

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Traditional bearings-only measurements (BOM) passive target tracking methods have an intrinsic shortage, that is, it depends on the established target models excessively. In order to solve the problem, a novel RL-based BOM tracking method is proposed. First, a reinforcement learning (RL)-based BOM target tracking framework is established, and sensor actions and rewards function are properly defined. Then, based on the typical Q-learning techniques, and Cerebellar model articulation computer (CMAC) method, a novel BOM tracking algorithm is proposed. Finally, a simulation example is provided to show effectiveness and efficiency of the proposed passive target tracking method.

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In this letter, a technique to improve the gain of ultra-wideband (UWB) planar antennas, by using low-profile frequency selective surface (FSS) based reflectors, is proposed. This technique not only enhances the gain of the planar UWB antennas but also guarantees a constant gain of maximum variation of 0.5 dB across the entire UWB, while keeping their attractive merits. To prove the effectiveness of the proposed technique, UWB coplanar waveguide (CPW) fed circular-disc antenna is installed above the proposed reflectors. As result, constant gain UWB antenna has been obtained.

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