Visible Light Communication System Design Using Raspberry Pi4B, LED Array, and MQTT Synchronization Protocol

Visible light communication is the next big thing in the future to overcome many limitations that RF-based communication has.  This study discusses the design of a wireless visible light communication system to transmit temperature and humidity information based on the Raspberry Pi and the MCP3008 Analog to Digital Converter. The system uses LEDs to transmit data. The photodiode is used to receive the optical signal. Raspberry Pi is used as the signal processor on both sides with the implementation of synchronization techniques and On-Off Keying modulation. The research was conducted in a dark room with a 2x2 LED Array configuration to minimize the effect of the external lighting prototype’s performance. The research carried out variations in the color of LED used, variations in the method of synchronization, and variations in the data rate transmission with BER value as the main parameter. This research contribution is to propose a simple visible light communication design that transmit and receive information in reference of room temperature and humidity using raspberry pi and DHT-11 sensor, while also implementing communications protocol to maximize synchronization in transmission thus minimizing the BER value in higher bit rate. The LED used is blue with an average voltage of 0.0423V for a value of 1 and 0.00448V for a value of 0. The transmission speed can be done from 1bps to 10kbps with BER 0.5 as a threshold parameter. The implementation of the synchronization method reduces the BER value by 0.0945 with the implementation of transmission calibration synchronization and decreases the BER value by 0.1221 using synchronization with the MQTT communication protocol. For further research, the development can be done by implementing Forward Error Correction (FEC) to minimize errors that occur in the transmission and collaborating with vendors with research in the same fiel

Valuation of 5G mmWave Fixed Wireless Access in Residence Area Analysis of Real Option for Wireless Broadband Service in Kota Wisata Cibubur Using Decision Tree and Black Scholes Model

Fixed Wireless Access (FWA) is one of the popular use cases in 5G, expected to replace conventional internet service. However, investing in a telecommunications project requires massive capital, so careful planning is usually required. In general, investments are valued by the standard Net Present Value (NPV) method. When the NPV is positive, the project is profitable. However, the NPV possibly will not be as expected due to uncertainty in the future. One of these is the number of subscribers. This research proposes using Real Option (RO) to analyze the FWA project with an uncertainty of the number of subscribers and compare it to the standard NPV method. From the result of the research, the standard NPV method produces a positive Expected NPV of $153,176. However, there is a 33$406,246. By using the decision tree in RO to evaluate the project, the managers have an option to delay the project from one to three years and eliminate negative NPV resulting in the Expected NPV of $250,038,$216,842, and $188,371. Using Black Scholes Model to delay the project from one to three years also results in a higher Expected NPV of$220,668, $209,593, and$219,428

Terahertz Imaging Simulation Using Silicon-based Microstrip Antenna and Horn Antenna for Breast Cancer Detection

Breast cancer is one of the most common cancers in the world that cause a lot of mortality. Early cancer detection is crucial to decrease morbidity and mortality rates worldwide. Effective treatment or early intervention is crucial before the disease becomes more incurable. This research contributes to proposing a THz imaging system for early cancer detection, especially breast cancer, by using the benefit of THz radiation. Some approaches are made differently from the previous research, such as the imaging method, the antenna type, and the material for the antenna with the expectation of producing an efficient system and better imaging results. The system consists of one microstrip antenna as a transmitter, 25 horn antenna as a receiver and a breast tissue model. All antenna is designed to meet the requirement specification. The receiver antenna will receive power from the transmitter which will vary due to the absorption of the breast model. The received power will be visualized into a 2D color image. The simulation was able to visualize an image of the breast tissue model. Received power varies from -16.280 dB to -55.241 dB which leads to different color levels to represent the model. Antenna radiation patterns also take a role to cause the phenomenon occurred that leads to differentiation of the breast tissue type. Based on the results, this research has able to simulate a THz imaging system for breast cancer. Further modification to the system can be done to improve the imaging results

Literature review: visible light communication system business model scheme for telecommunication business in Indonesia

The telecommunication sector mainly comprises operators, vendors, and regulators. In Indonesia, tele- communications operator companies tend to decrease profits from the first quarter of 2017 to the third quarter of 2018. This condition is due to the tight competition of telecommunication service providers, high operational costs, and digital transformation that does not provide substantial revenue for the company. Telecommunica- tions operators need other service options that can expand target market segmentation. It aims to open up a new blue ocean as a new source of income. The world is getting closer to massive communication technology, so high-speed communication is needed. Therefore, telecommunications operators can open new service options based on the visible light spectrum as their communication resources. This option can be integrated with ambient lighting, a wide spectrum ranging from radio waves, and greater bandwidth, making visible light suitable for IoT- 5G services. This research aims to design a wireless visible light communication business model. Several frame- works are used, such as the magic triangle of St. Gallen, Osterwalder Business Model Canvas, and PESTLE analysis. The business model design results in a business model with B2B market segmentation being the main focus and B2C market segmentation to acquire retail customers

BANDWIDTH AND GAIN ENHANCEMENT OF MICROSTRIP ANTENNA USING DEFECTED GROUND STRUCTURE AND HORIZONTAL PATCH GAP

This research proposed microstrip antenna design using the Defected Ground Structure (DGS) and horizontal patch gap (HPG) for bandwidth and enhancement purposes. This design is to reduce the weakness of a microstrip antenna, which has small gain and narrow bandwidth. The design was simulated in CST Microwave Studio with a working frequency of 2.4 GHz. The design consists of three stages model, i.e., conventional design, DGS modification, and the combination DGS using a Horizontal Patch Gap (DGSHPG). The radius of the conventional circular patch is 16.7 mm. The substrate has 4.6 of dielectric constant, 1.6 of substrate height, and 0.025 of the loss tangent. The simulation results show that the DGS design produces more bandwidth and gain than a conventional design, where the bandwidth and gain improvement are 421.2 MHz and 1.73 dB, respectively. The DGS model is combined with a gap that separates the circular patch (DGSHPG) to achieve the optimum design. The results show the bandwidth and gain improvement of more than 50% and 18.1% compared to the DGS design, respectively. Other parameter performance also shows improvement, such as a reflection factor with -53.3 dB at the center frequency. The physical change also influences the patch’s radius, where it is reduced around 1.4 mm or 8.4% from the original design. Overall, the proposed design has succeeded in achieving bandwidth and gain enhancement and reducing the patch dimension

Perancangan dan Analisa Kinerja Fiber to the Building (FTTB) untuk Mendukung Smart Building di Daerah Urban

The development of digital technology makes it easy for humans to do activities, including compliance with the requirement of voice, data, and video communication in office buildings. Infrastructures are a primary consideration for a reliable connection, large-capacity, and stable communication lines. Recently, Fiber-optic communication systems are now the backbone of information signal delivery technology. This paper proposes a design of optical fiber transmission media for deployment in urban office buildings. It has been called fiber to the building (FTTB), which uses a fiber optic communication system to support the availability of multimedia network in an office area. A typical office building in an urban area has a multilevel structure that is used by various companies with multimedia network access services to support business activities. This study considers XGPON technology as a fiber optic-based broadband access technology that is deemed appropriate to the needs of the use of a multimedia network. The design begins with conducting a data collection survey. The next is the chosen device components based on the estimated distribution of the number of users. There are three parameters will be calculated include Power Link Budget (PLB), Rise Time Budget (RTB), and Bit Error Rate (BER), to determine the design feasibility. Based on PLB, RTB, and BER data, the proposed fiber to the building (FTTB) can meet the parameters to be achieved in the design, namely PLB of -27,24 dBm for downstream and -11,68 dBm for upstream, the value of is 0,049 ns, and value of BER is 0,186 x 10-1085. The design of FTTB can meet the requirement of users with a bandwidth of 9014,4 Mbps for 1200 users

インドネシアの州の形状変化分析に基づく経済指標評価

This paper presents our work on analyzing provincial economic differences in Indonesia based on economic indicators. The data were obtained from the official website of Indonesian Central Bureau of Statistics (Badan Pusat Statistik Indonesia) that is responsible for conducting national statistical survey, and is a non-departmental government institute which directly report to the president. In this paper, we studied the provinces Gross Domestic Product (GDP) percentage, the average monthly expenditure per capita for food, the electricity distribution per province, and the distribution of cleaned water. We conduct the statistical analysis to data of 33 provinces in a time series from the year 2007 to 2015. We performed the deformation analysis to indicate the local economics movement/changes. The analysis of GDP percentage in 2000 to 2013 shows that the economic distribution tends to be from Java Island to other provinces. This analysis indicates the emerging regional economy which is happening in provinces located outside the Java Island. Our shape analysis of the deformation data of the average monthly food expenditure and GDP percentage shows that the higher expenditure group of provinces tends to move down and the lower expenditure group of provinces tends to move up. Therefore, the trend is that the food expenditure and GDP becomes closer to the average value in all provinces in Indonesia. For electricity distribution per province and the GDP percentage, the deformation analysis shows that there are almost no significant changes in all provinces. From clean water and the GDP percentage, the deformation shows that the Jakarta data tends to move down insignificantly, although almost all other provinces analysis move up. These results indicate that economic emergence happened in various provinces

High-Performance Radiation Design of a Planar Bow-tie Antenna Combined with a Dielectric Lens and Cascaded Matching Layers at Terahertz Frequencies

The demand for high-speed data transmission has increased significantly in the last decades. Terahertz (THz) frequency, which lies between 100 GHz to 10 THz, has been considered as the solution to the demand. However, the low gain and low efficiency of a THz antenna remain to be issues that hinder reasonable performance for various applications. This paper proposes the design of a high-gain and high-efficiency planar bow-tie antenna for applications in the THz frequency. A planar bow-tie on a high-resistivity silicon substrate is considered to obtain the broadband characteristics. To increase the gain and efficiency, a dielectric silicon lens and a matching layer based on the quarter-wavelength are applied in the design. From simulations using Computer Simulation Technology (CST) Microwave Studio, gain and radiation efficiency of up to 32.69 dB and 90.4% are obtained, respectively. This proposed design has shown high radiation performance suitable for high-speed transmission systems

テラヘルツ帯シリコン誘電体レンズアンテナおよびアッテネータに関する研究

博士(工学)doctoral創造科学技術大学院静岡大学甲第868号ET