![]() With the development of the Internet of Things (IoT) technology, two-dimensional (2D) barcodes are widely used in smart IoT applications as a perception portal. The results prove the ability of the method proposed to limit the circulating currents to negligible values. To study its behavior and to improve the control method, simulations with two parallel-connected inverters have been firstly conducted, then additional simulations have been performed with increasing complexity to demonstrate the quality of the algorithm. The system has been simulated in a Simulink environment. The hardware implemented is the same for every inverter therefore, the addition of a new module does not require redesign, enhancing system modularity. Each of the inverters, connected in parallel, is conceived to be equipped with an FPGA that controls the Pulse-Width Modulation (PWM) waveform without intercommunication with the others. In this paper, a new control method aimed at this purpose and conceived to be implemented on a Field Programmable Gate Array (FPGA) device is presented. In a multiple parallel-connected inverters system, limiting the circulating current phenomenon is mandatory since it may influence efficiency and reliability. Moreover, the gain in the spectral efficiency with sacrificing by SNR is achieved. The MIMO-OFDM with LDPC and STC system obtain a gain about 5 dB in SNR at 10^-4 BER. It is seen from the simulation results, the MIMO-OFDM system combined with LDPC code and STC can perform better performance regarding bit error rate (BER) at the indicated SNR. LDPC performs better performance compared with other codes, therefore, LDPC is used with different code rate. ![]() Several codes such as Conventional Code (CC), Low Density Parity Check (LDPC) code and Reed Solomon (RS) code were studied. To exploit the advantages of ECC regarding the cancelation of channel effect to the received signals. To increase the system throughput, several modulation formats are used with different constellation maps such as (BPSK, QPSK, 16QAM, and 64 QAM). OFDM which divides channel into several sub-channels is employed with different number of sub-carriers. The receiver combined received signals using maximum ratio combiner (MRC) to increase a received signal to noise ratio (SNR). In this work, the actual MIMO system was implemented with two transmission,and a reception antennas. The combination of the aforementioned systems can be improved with the system outcome significantly. As a result, it improved the system performance. In addition, space time code (STC) that transmits replica of transmitted signal through different sub-channels can obtain the spatial diversity. Error correction code (ECC) can overcome the drawback of channel affect. ![]() However, the received signal can be corrupted due to selectivity of the channel. The Multiple Input Multiple Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) system can enhance performance of system toward high data rate requirements. The growing demand for high data rate with high quality of service (QoS) is required for a re-design of current systems. The results show that the theoretical finding are fully confirmed only in the MCU implementation, while on FPGA, the choice of one method with respect to the other depends on the optimization feature (i.e., time or area) that has been decided as a preference in the specific application. As a benchmark in the analysis, the well-established Forney's method is exploited: it has been implemented in the same configurations and on the same hardware platforms for a proper comparison. ![]() The performances have been evaluated in terms of resource usage and output delay for the FPGA and in terms of code execution time for the MCU. Several configurations of the encoded message chosen between those typically used in different applications have been designed to be run on an FPGA (field programmable gate array) device and an MCU (microcontroller unit). under different systems configurations and hardware platforms. This paper aims to assess the performance of an innovative algorithm introduced in the literature by Lu et al. RS decoders are composed of several blocks: among them, many efforts have been made to optimize the error magnitude evaluation module. Reed-Solomon (RS) codes are one of the most used solutions for error correction logic in data communications.
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