A Real-Time Visible Light Communication System on Chip Design for High Speed Wireless Communication

The increasing demand of wireless communication bandwidth due to advancement of IoT and smartphone technology, requires the new wireless communication technology that can provide high speed wireless communication. The Visible Light Communication (VLC) has been proven can provide multi gigabit wireless communication throughput using unlicensed visible light spectrum. Therefore, VLC is a promising technology to solve bandwidth limitation problem. In order to achieve high speed throughput, VLC signal processing has to be implemented using Application Specific Integrated Circuits (ASICs) technology. In this research, we develop a baseband processor architecture for VLC application. We use System on Chip (SoC) design approach to reduce design time and easy system integration to various applications. In order to increase spectrum efficiency, we utilize OFDM modulation scheme. Several OFDM processing blocks, such as synchronizer, FFT/IFFT, modulator, demodulator, are designed in the system. The real-time system performance is verified in FPGA based system prototyping. The design includes optical wireless front end module, baseband processing and network layer. The developed prototype shows a real-time performance for high speed internet access

Smart Navigation Equipment Monitoring System

Digital image processing is a processing of digital frames using digital computation. Image processing has been used in many sectors such as military, biomedics, and in this paper, the authors will implement it in the civil aviation sector by introducing a new method to monitor an aviation navigation equipment. It can be used on all LED-based Built-in Monitor navigation equipment, despite it is a low-cost system. The image processing of this research is done by doing perspective correction and then continue with BLOB detection in a segmentation stage. The final result will be displayed on a web page. Compared to its predecessor, this method gives better flexibility which does not need to be electrically connected with monitored equipment and not limited to certain brands

VLSI Architecture for Configurable and Low-Complexity Design of Hard-Decision Viterbi Decoding Algorithm

Convolutional encoding and data decoding are fundamental processes in convolutional error correction. One of the most popular error correction methods in decoding is the Viterbi algorithm. It is extensively implemented in many digital communication applications. Its VLSI design challenges are about area, speed, power, complexity and configurability. In this research, we specifically propose a VLSI architecture for a configurable and low-complexity design of a hard-decision Viterbi decoding algorithm. The configurable and low-complexity design is achieved by designing a generic VLSI architecture, optimizing each processing element (PE) at the logical operation level and designing a conditional adapter. The proposed design can be configured for any predefined number of trace-backs, only by changing the trace-back parameter value. Its computational process only needs N + 2 clock cycles latency, with N is the number of trace-backs. Its configurability function has been proven for N = 8, N = 16, N = 32 and N = 64. Furthermore, the proposed design was synthesized and evaluated in Xilinx and Altera FPGA target boards for area consumption and speed performance

An Infrastructural IP for Interactive MPEG-4 SoC Functional Verification

This paper introduces a specific architecture including an infrastructural IP for functional verification and diagnostics, which is suitable for functional core-based testing of an MPEG4 SoC. Our advanced MPEG4 SoC results in a high complexity SoC with limited physical access to many different functional cores. The proposed test method provides direct monitoring and control for each core, which enables core verification at actual speed. It significantly decreases the verification time due to the large number of required test vectors in typical MPEG4 verification. Furthermore, it also makes the system scalable for functional core expansion due to upgrading of standards. The proposed infrastructural IP is also linked to PC-based interactive tools to simplify the verification of individual and integrated cores. It also provides detailed diagnostic data that enables simple system debugging. The debugging tools also feature test-pattern generation and simulation of expected values. Actual system implementation has shown full functionality of our proposed method

Rancang Bangun Layer Fisik Visible Light Communication Pada Sistem Transmisi Audio

Kini, fungsi LED tidak hanya sebagai penerangan saja, melainkan dapat dimanfaatkan sebagai media komunikasi. Teknologi ini lazim disebut sebagai komunikasi cahaya tampak atau VLC, yang mana telah mulai diaplikasikan pada area-area yang rentan gelombang elektromagnetik seperti rumah sakit, kabin pesawat, bandara, markas militer dan lain sebagainya. Media yang umumnya dijadikan objek transmisi data adalah berupa gambar, video, audio (musik), teks, bahkan paket data untuk keperluan browsing internet. Penelitian ini mengimplementasikan sistem VLC yang berfokus pada layer fisik, yakni pada bagian Analog Front-End (AFE). Sistem yang dirancang terdiri atas modul AFE transmitter sebagai modulator dan AFE receiver sebagai demodulator. Rancangan AFE transmitter mengadopsi prinsip dari modul Bias-T, dengan fungsi yang sama namun memiliki keunggulan pada sisi low-cost. Sedangkan pada bagian AFE receiver, terdapat modul DC-offset remover yang berfungsi untuk mereduksi sinyal DC dari ambient light. Hasil demonstrasi menunjukkan bahwa sistem secara fungsional dapat digunakan untuk transmisi sinyal audio via cahaya tampak dan secara langsung ditampilkan ke loudspeaker yang mana pengamatan dilakukan secara langsung dengan membandingkan amplitude sinyal input ke LED driver dengan sinyal output dari stage terakhir dari AFE receiver. Berdasarkan pengujian dapat ditunjukkan bahwa bandwidth optimum dari AFE transceiver adalah dalam rentang 50 kHz sampai 450 kHz (referensi redaman pada frekuensi cut-off = -3 dB) dan jarak maksimum transmisi data adalah 40 cm dengan sudut elevasi penerimaan sebesar 0 derajatCurrently, LED functions not only as illumination purpose but also can be used as a communication device. Commonly, this technology is called as "visible light communication (VLC)", which has begun to be applied in areas susceptible to electromagnetic waves, such as hospitals, aircraft cabins, airports, military headquarters and etc. Generally, the media, which is used as object of the data transmission, e.g. digital images, video, audio (music only), texts, and even data packets for internet browsing purposes. This research implements a VLC system that focuses on the physical layer, especially in Analog Front-End (AFE) part. The designed system consists of an AFE transmitter module as a modulator and an AFE receiver as a demodulator. The designing AFE transmitter adopts the Bias-T module principle, it has same the functionality but extremely lower in the cost factor. While in the AFE receiver part, the DC-offset remover module is implemented, it has a function to reduce the DC signal that generated from ambient light. The results of demonstration show that the system, functionally, can be used for transmitting audio signals via visible light and the received data can be displayed to the loudspeaker directly.  In this work, the data observation is done by comparing the amplitude of input signal connected to the driver LED against the output signal from the last stage of the AFE receiver. From the test results, it can be shown that the optimum bandwidth of the AFE transceiver is about 50 kHz to 450 kHz (with attenuation at fc = -3 dB as a reference) and the maximum distance for data transmission is 40 cm and angle of reception is 0

A High-Accuracy of Transmission Line Faults (TLFs) Classification based on Convolutional Neural Network

To improve power system reliability, a protection mechanism is highly needed. Early detection can be used to prevent failures in the power transmission line (TL). A classification system method is widely used to protect against false detection as well as assist the decision analysis. Each TL signal has a continuous pattern in which it can be detected and classified by the conventional methods, i.e., wavelet feature extraction and artificial neural network (ANN). However, the accuracy resulting from these mentioned models is relatively low. To overcome this issue, we propose a machine learning-based on Convolutional Neural Network (CNN) for the transmission line faults (TLFs) application. CNN is more suitable for pattern recognition compared to conventional ANN and ANN with Discrete Wavelet Transform (DWT) feature extraction. In this work, we first simulate our proposed model by using Simulink® and Matlab®. This simulation generates a fault signal dataset, which is divided into 45.738 data training and 4.752 data tests. Later, we design the number of machine learning classifiers. Each model classifier is trained by exposing it to the same dataset. The CNN design, with raw input, is determined as an optimal output model from the training process with 100% accuracy

Design and Implementation of Real Time Noise Cancellation System based on Spectral Subtraction Method

AbstractIn this paper, a real-time digital signal noise cancellation system is designed based on Spectral Subtraction Method. The system cancels the noise in frequency domain by estimating the noise energy spectral from a noisy input. Since that method is performed in frequency domain with polar form, a time to frequency domain and rectangular to polar transformer with each of their complement circuits are needed to perform the noise cancellation operation. Considering high speed computation with lower system frequency for a real-time processing and low power consumption, an FPGA based full-hardware implementation is used in proposed system. As a result, the proposed noise cancellation system implementation result is able to perform a real time noise cancellation with the SNR value of 71dB and use about 47,000 FPGA logic elements with 32 bits data resolution

Design of AXI4-Stream based Modulator IP Core for Visible Light Communication System-on-Chip

In this paper, the design of AXI4-Stream based modulator IP core for Visible Light Communication is reported. The modulator IP core conforms to the AXI4-Stream protocol standard, which is widely used in System-on-Chip (SoC) design. There are three modulation types in this IP core namely, Binary Phase Shift Keying (BPSK), Quadrature Phase Shift Keying (QPSK), and Quadrature Amplitude Modulation-16 (QAM-16). These modulation types are commonly used in DCO-OFDM system. The modulation types can be selected programmatically from software that runs in main processor by accessing the control register. The output of the modulator is designed for DCO-OFDM modulation using 64-point IFFT. According to the simulation results, this modulator IP core can achieve a throughput of 95.36 Mb/s, 184.77 Mb/s, and 347.81 Mb/s for BPSK, QPSK, and QAM-16, respectively. This modulator IP core is reusable in DCO-OFDM system, so it increases productivity in DCO-OFDM system design

Noise and Bandwidth Consideration in Designing Op-Amp Based Transimpedance Amplifier for VLC

In a visible light communication (VLC) system, there are many modules involved. One of the important modules is Transimpedance Amplifier (TIA) that resides in the analog front-end receiver (Rx-AFE). TIA is responsible for performing signal conversion from current signal, which is provided from the photodiode (PD) to voltage signal. It is the reason why the TIA should be operating in low noise condition and wide bandwidth of frequency. These will enable a flexible coverage of the VLC system in performing its signal processing. Hence, in this research, we provide considerations of the noise and frequency bandwidth analysis in designing TIA to cope with the required design specification of a VLC system

Noise Analysis in VLC Optical Link based Discrette OP-AMP Trans-impedance Amplifier (TIA)

To design Visible Light Communication (VLC) system, there are several requirements that needs to be met. One of the requirements is an active component selection (e.g. Op Amp). As an ideal communication system, VLC system has to be able to provides wide bandwidth access with minimum noise. The Transimpedance amplifiers (TIAs) is one of main components in optical system which is placed in the first stage of receiver system. It is used to convert the current output from photodiode to voltage. We have designed a 1 MHz fGBW TIA with low noise (in μVrms range). This paper aims to explain the design and implementation of TIA circuit with photovoltaic topology which cover empirical calculations and simulation of TIA’s bandwidth and its noise sources, i.e. resistor feedback noise, current noise, voltage noise and total noise based on RSS. The OP-AMP is chosen from Texas Instruments product, OPA 380, and photodiode is chosen from OSRAM, SFH213, then simulated by TINA-TI SPICE® software. The noise in TIA circuit is analyzed clearly. The developed kit is ready to be implemented in VLC system