ヨサファット テトォコ スリ スマンティヨ

This paper presents a preliminary design of a conformal subarray antenna for circularly polarized synthetic aperture radar (CP-SAR) onboard UAV. The CP-SAR is operated in C-band with the center frequency of 5.3 GHz and bandwidth of 400 MHz. Limitation space inside the fuselage and the CP-SAR signal attenuation issue caused by the fuselage material will be attempted to overcome by installing a conformal CP-SAR antenna wrap-around outside the UAV fuselage. An osculating circle with a radius curvature of 920 mm is used to reference fuselage curvature to bend the antenna. Simulation results show the conformal antenna achieves excellent performance characteristics. The antenna is currently fabricated and will be validated in the next work.

Unmanned aerial vehicle (UAV) can be used to serve as aerial wireless base stations when the cellular network collapses. Most of the studies on UAV-served communication assumed that the users are located at outdoor and their position are coordinated as two-dimensional. However, most user traffic occurs indoors and a communication error is caused by a low throughput may cause casualties in indoor emergency. Recent studies that handle indoor disaster situation, only considered the UAV coverage. Therefore, practical research is needed for user's safety. In this paper, we propose uplink non-orthogonal multiple access for based full-duplex UAV increasing throughput in indoor disaster situation. We consider and modify indoor-to-outdoor path loss model for indoor users served by outdoor UAV, and the altitude of UAV ensuring signal to interference plus noise ratio. Simulation results show that the proposed model improves the performance of throughput than conventional scheme.

We are conducting an experiment for Circularly Polarized Synthetic Aperture Radar (CP-SAR) using Unmanned Aerial Vehicle (UAV). Raw image data obtained by radar is processed by FPGA on UAV. The Range Doppler Algorithm (RDA) is used for our image processing. Currently, our image processing system uses the KC705 evaluation board with Kintex-7 FPGA, and it communicates with CP-SAR controller unit to perform image processing. This KC705 evaluation board is a multipurpose board and has parts that are not used in image processing. Therefore, we select the parts required for image processing and design a board for SAR image processing that is smaller and lighter than the KC705.

In this research, we carried out the analysis of long-term continuous ground deformation (subsidence or uplift) based on C-band Differential Interferometric Synthetic Aperture Radar (DInSAR). This technique is employed to investigate ground deformation of the Yokohama and Miura cities of Kanagawa prefecture, Japan. The observation was starting from October 2Sth, 2017 to May 3rd, 2019. The study data used Sentinel-1 C-band data provided by the European Space Agency (ESA). The results of the research show that the maximum subsidence velocity of ground deformation was 5.89 cm/year, and the maximum uplift velocity was 8.36 cm/year in Yokohama city. Also, in Miura city, the maximum subsidence velocity of the ground deformation was 4.5 cm/year, and the maximum uplift velocity was 11.4 cm/year. In both cities, satellite SAR analysis results have the same tendency with each GNSS control point, and the difference of the subsidence was within approximately 0.5 cm. This result shows the analysis data of DInSAR was almost equal compare to the global navigation satellite system (GNSS) data by Geographical Survey Institute (GSI). This research shows the capability of the DInSAR technique to investigate long-term continuous ground surface conditions over a wide area with high accuracy in association with the occurrence of heavy rains and typhoons.

Previously, many researchers have developed various methods to observe land subsidence in the Sidoarjo area using synthetic aperture radar (SAR). This research proposed the equation to estimate the current and volume of outflow of hot mud in the study area using various SAR missions and a Bridging Consecutive DInSAR (BC-DInSAR). The analysis result of the proposed techniques was validated using differential GPS (DGPS) and acquired an accuracy of 0.46 m.

Forest fires, especially on peatlands, constitute a significant problem that is often faced in Indonesia. Forest fires that occur on peatlands are caused because the peatlands have been degraded due to deforestation, with the aim of utilizing peatlands for forestry and agricultural cultivation activities. Efforts to mitigate forest fires on peatlands need to be made. The first thing to do is to map peatlands that have a high risk of burning. In order to cover a large area, remote sensing technology is needed. Peatlands that have subsided are identical to peatlands that are dry, so they burn easily. SAR interferometry has the ability to detect the subsidence of peatlands. Combined with the Wosten model, areas with a high potential risk of forest fire on peatland can be mapped, and this has been demonstrated in this research.

This paper mainly studies despeckling method for Synthetic Aperture Radar (SAR) image. The denoising method based on deep learning usually needs a lot of samples and noiseless reference images to realize data regression. However, speckle noise is very different from random additive noise such as white Gaussian noise in that its distribution is affected by the background target and it is hard to obtain completely noiseless reference images. Therefore, we proposed a local learning method and constructed a deep learning model to overcome this challenge, which named Speckle-Denoise-Net (SD-Net). In proposed method, the speckle noise can be effectively suppressed without the need for noiseless reference images. It can not only solve the problem of lacking training samples and having excessive image size, but also take advantage of unsupervised learning for inherent noise to make a good balance between smoothing and structure-preserving compared With other methods. At present, the test results of this method (Including denoising effect, original information retention, and algorithm speed) have exceeded most of the existing traditional denoising algorithms and deep learning methods, which allow it to bring new inspirations to solve the problem of speckle noise.

GPM is a satellite that capture global precipitation data, using radar, microwave, and infrared sensor. The data has a rough spatial resolution, so it is necessary to detail the spatial resolution so that it can be used in a more local area. Geographically Weighted Regression (GWR) is a regression-based method that can be used to detail spatial resolution by utilizing the relationship of an independent variable, in this case precipitation, with a predictor variable that has a strong correlation. Topography is a biophysical element that is closely related to precipitation, for example, local type of rainfall or orographic type of rain. ALOS PALSAR is a radar sensor satellite that records the altitude of the earth's surface. The DEM product can be processed into topographic elements, namely Slope and Aspect, so that it is expected to be a predictor for the GWR model. The results of the model formula show that the slope has the greatest influence, the DEM has the opposite value to the slope, and the coefficient of the distribution of the relevant Aspects reflects the orographic conditions. The results of the accuracy test show that GWR is not only able to detail the resolution but also slightly improve the accuracy of GPM accuracy.

The design of a broadband circularly-polarized subarray antenna for airborne synthetic aperture radar is presented in this paper. The proposed antenna operates in X-band at the center frequency of 9.5 GHz with a bandwidth of 400 MHz. The subarray antenna employs 16 patches with 4×4 matrix formation and uniform patch separation of 0.7λs. The hybrid sequential rotation technique on the feeding network is proposed to obtain a wide axial-ratio bandwidth and a balanced radiation pattern. The proposed antenna consists of two stacked substrates with identical specifications. Generation of circular polarization wave applies a curved-truncation patch on the radiator patch printed on the top layer bottom substrate. Broadening impedance bandwidth and gain enhancement are improved by an additional parasitic patch with circle-slotted printed on the upper layer. A floating copper on the upper layer is also attempted to improve the gain. Simulation results achieve the impedance bandwidth of 3.533 GHz (37.2%), axial-ratio bandwidth of 3.436 GHz (36.17%), the gain of 19.16 dBic, and the antenna size of 107 mm x 107 mm. The half-power beam-width in both azimuth and range direction is 16.4° and 15.9° at the center frequency of 9.5 GHz.

Aviation turbulence is one of the dangerous events of a flight. This hazard impacts people and aircraft. One source of information on turbulence events comes from the NTSC report. Then one of the causes of flight turbulence is the presence of convective clouds. Indonesia, which is located in the tropics, is an area that is very active in its convective activities. Descriptive analysis was used in this study. There were three aviation turbulence events in 2016-2020, namely on 4 May 2016, 6 May 2016, and 24 October 2017. All incidents of aviation turbulence occurred wind shear around the incident location based on upper-air observation data. In two turbulence events, there are convective clouds around the scene.

Land subsidence is a problem in several big cities and areas in Indonesia; some of them occurred in Jakarta, Bandung, Semarang, and the North Coast of Java location. The subsidence conditions are different and highly dependent on many factors, including geological and excessive groundwater extraction. One of the cities experiencing severe subsidence conditions in Indonesia is Bandung. This research is based on Interferometric SAR analysis using C-Band Sentinel 1A frequency data released by the European Space Agency (ESA), recorded on 11 November 2018 and 18 November 2019. Based on the analysis of SAR interferometry, Bandung City experienced subsidence with an average size of 6 cm per year. The city of Bandung is located between the mountains and can be described as a bowl. The city of Bandung itself is formed from alluvial plains resulting from the sedimentation process from the surrounding mountains. Geologically, the city of Bandung can be described as a city composed of materials that have not undergone a perfect consolidation process. This condition causes the city of Bandung to be prone to land subsidence disasters. In addition, another factor that plays a dominant role in the process of excessive groundwater extraction by residential and primarily industrial activities scattered in the Bandung area. If not handled properly, the phenomenon of land subsidence in the city of Bandung will cause a very detrimental impact, reduce the carrying capacity of the environment, and threaten the sustainability of the city. Among the actual effects on the broader area in Bandung that is affected by floods, especially during the rainy season.

This paper presents a compact circular polarization array antenna. 4-antenna array is taken to compose 64-antenna array on Glass-Epoxy substrates varepsilon r 4.6,texttan delta 0.010. 4-antenna array is made by orthogonal arrangement, parallel feeding, and the minimum length of feeding wire. 16-antenna array is composed to minimize feeding length and loss by high texttan delta under the synchronous condition of each antenna. By 3D computer simulation, wideband characteristics were obtained as axial ratio less than 2dB, directive gain 21.8 dBi or more, and the size is the 162 mm width. This configuration contributes to reduce the cost of easy chemical processing.

Several techniques have proposed to observe long-term land deformation using phase information of synthetic aperture radar (SAR), for example, InSAR, DInSAR, PS-InSAR, SBAS using spaceborne SAR images. But every mission of spaceborne SAR has an orbit duty period less than ten years and other problems of discontinuity or blank period of observation using the similar specification of sensors. Hence land deformation with an observed time of more than ten years is not available to be monitored continuously using a single mission. This research proposed a method called Bridging Consecutive DInSAR (BC-DInSAR) to connect Consecutive DInSAR. These methods were employed to investigate land deformation and the impact caused by hot mudflow accident at Regency of Sidoarjo, Indonesia, where this disaster happened on 29 May 2006 and is flowing until now. The differential GPS data since 2006 was employed to validate the analysis result of BC-DInSAR, which obtained 0.46 m RMS error.

In this research, we propose a sub-array antenna that is the core of the X-band antenna for circularly polarized SAR (CP-SAR) onboard an unmanned aerial vehicle (UAV). We aim to realize a high-resolution CP-SAR with a wide bandwidth of 800MHz and a low axis ratio. For this purpose, we designed an ax-shaped radial surface with square slots and prototyped a low-axis band antenna using sequential array technology arranged in 4×4. The basic characteristics of the prototype antenna were verified by experiments in an anechoic chamber.

Kelok Sembilan flyover is located in West Sumatra-Riau province connection, Indonesia. Landslide occurs along with the connection every year. However, detecting and obtaining scientific information about the potential landslide zone in the area is difficult because it is mountainous, and there is no disaster equipment monitoring installed on it. Here, we identify the area that potential landslide using Satellite Radar SAR Synthetic Aperture Radar) technology with high accuracy until millimeter unit. Also, we showed how to observe the potential landslide with a low penetrate radar signal (C-band) and shifted polarization due to the topography in the vegetation area. The observation data is extracting from satellite Sentinel- 1A/B provided by the European Space Agency (ESA). The satellite is C-band frequency with 5.5 cm wavelength and 5 x 20-meter range-azimuth resolution. The acquisition time of SAR data is starting from October 2014 to August 2018, which is supported by 119 images. Processing the SAR data is using the Quasi-Persistent Scatterer technique to improve the number of scatterers in a non-urban area. Both ascending and descending orbit of the satellite with both VV and VH polarization were selected to confirm potential landslide detection consistency. The result of processing was validated with GPS geodetic by DGPS network configuration. Based on the QPS processing, five areas with significant land movement have been detected one of them is collapse after ten days since the last data observation. The land movement range in the area is approximately more than 500 millimeters in four years.

Pekanbaru City, Riau Province, Indonesia located at 0°25'29.20"- 0°39'15.22" N and 101°20'43.39"- 101°34'25.60" E. This research aims to study the common causes of flooding in Pekanbaru city with a good geological condition. Research in the flood area of the city of Pekanbaru using primary and secondary data geological, geomorphological, rainfall, and land use data. Information about this earth system combined with geographic information system (GIS) analysis using a small unmanned aerial vehicle (UAV) / drones including Geographic Positioning Systems (GPS) combined with online coordinate systems that can help spatial analysis to determine the level of vulnerability of flood disasters by producing a visual mapping model. The study shows that 4 locations were found vulnerable to being affected by flooding when it rained. The flood impact in those areas happened because those locations are in a geomorphological system with a low topographic area, the natural river system that controls the water to the main river, and a poor water escape-system / drainage. The geomorphological analysis showed two geomorphological units, i.e., lowland denudational and lowland structural with river flow-pattern that is dendritic, sub-dendritic, and parallel. Rainfall is quite high in 2018 with 2621.5 mm and caused flood-prone areas, which are divided into three categories: Non-vulnerable area (64.575%), Medium Vulnerable area (23,386%), and Vulnerable area (12,039%) from the entire of the research area.

Recently, the development of compact, lightweight, and low-power microwave remote sensed sensors for high-temperature of space environment becomes an interesting field to be explored for a future planetary mission. In this research, we propose a microstrip antenna for Circularly Polarized Synthetic Aperture Radar (CP-SAR), which has a heat resistance and enables observation in a high-temperature space environment. In this preliminary research, we investigated the antenna material with a target heat-resistant temperature of about 500°C, and the final temperature is 1000°C. The proposed antenna is a compact and lightweight microstrip antenna with wiring printed on a two-layer dielectric substrate. The antenna has to be wideband to realize the high resolution of Circularly Polarized SAR. We considered using alumina ceramics for the substrate and tungsten for the conductor as the material for the antenna. Both materials have excellent characteristics of heat resistance, and we consider the conductivity of tungsten will be sufficient. As a result of the heat resistance test at 500°C and 1000°C, no significant deformation or deterioration occurred in the material, and a slight change in impedance value due to oxidation of tungsten was observed. The antenna design was performed in the C band with a center frequency of 5.3 GHz. The design of the conventional circularly polarized antenna and simulated it using the electromagnetic field analysis software CST Studio Suite. The result shows that the reflection loss Sll was exceeded 0.4 GHz that centered on 5.3 GHz and the gain of center frequency was 5.95 dBic. However, the antenna design needs further improvement due to the narrow axial ratio bandwidth. In the fabrication of the prototype, a 1. 0mum tungsten thin film was formed on the alumina plate by a sputtering technique. The accuracy of this sputtering is about 0.1 mm. Further investigation is required regarding the selection of connectors, other peripheral parts, and their connection methods. The measurement shows a large deviation in the peak of the return loss Sll. Based on the measurement result of relative permittivity of the ceramic substrate, it shows an inhomogeneous value with average value varepsilon mathrm{r}=5.78, that we employed this value in the simulation. Therefore, improvement of material and manufacturing techniques are required to improve the heat resistance and performance of the antenna in further research.

Chiba University proposed and developed airborne and high altitude platform system (HAPS) onboard C band circularly polarized synthetic aperture radar (CP-SAR) for environment and disaster monitoring on altitude 2-20 km. This paper explains concept, system configuration, RF system and antenna, and flight test of CP-SAR in Hinotori-C2 (Firebird-C2) mission onboard CN235MPA aircraft on 14-15 March 2018 at Indonesia. The result of flight test depicts full polarimetric CP images that shows good performance of CP-SAR. The assessment of CP image analysis, and novel image classification using axial ratio (AR), ellipticity (ε), and polarization ratio (p) are discussed. We plan to hold the flight test of HAPS onboard CP-SAR in 2023.

In this article, airborne broadband (maximum 400 MHz bandwidth) C-band circularly polarized synthetic aperture radar (SAR) is proposed and developed for further study on airborne compact polarized synthetic aperture radar (CP SAR) system using circular polarization. This article explains the scattering characteristic of circular polarization as the concept of circularly polarized SAR, system configuration, RF system and antenna, ground test, and flight test of circularly polarized SAR in Hinotori-C2 (Firebird-C2) mission onboard CN235MPA aircraft on 14 and 15 March 2018 at South Celebes, Indonesia. The result of the flight test depicts multipath full polarimetric circularly polarized images that show good performance of circularly polarized SAR and matched well to the result of the ground test of a multipolarized single pulse. The circularly polarized scattering clarification using trihedral, cylindrical, and omni corner reflectors (TCR, CCR, and OCR), assessment of circularly polarized image analysis, and image classification using the conventional axial ratio (AR), ellipticity (ε), and polarization ratio (ρ) are discussed. The proposed circularly polarized SAR will enrich the existing CP SAR systems and could be employed in further study of CP SAR calibration technique, also applications development for the environment and disaster monitoring using CP SAR.

In this paper, the development and characterization of three-dimension (3D) printed wideband pyramidal horn antenna equipped with binomial polarizer is presented. The proposed pyramidal horn antenna which is designed to operate at the X-band frequency and optimized to produce circularly polarized waves is intended to be used for circularly polarized synthetic aperture radar (CP-SAR) application. The optimized antenna design is manufactured using 3D printing technology for fast prototyping time, low cost, and light weight which is very suitable for small platform of CP-SAR sensor. The performance of realized antenna has demonstrated the fractional impedance bandwidth of 26% for S11 below-10dB, the axial-ratio bandwidth of 6.2% below 3dB, and the gain achievement up to 12dBic at the desired frequency.

This article presents the design and analysis of an ultrawideband (UWB) circularly polarized (CP) antenna element and its array. First, an UWB CP antenna element using circular-arc-shaped monopole (CASM) with asymmetric ground plane is proposed. Characteristic mode analysis (CMA) is used to investigate its CP operating mechanism, providing physical insights into different modes (mode currents and characteristic radiation fields) at various frequencies. The CMA results show that the asymmetric ground plane makes great contribution to produce CP radiation in the lower frequency band, while another upper CP band is generated by CASM. Thus, the overall 3 dB axial ratio bandwidth (ARBW) of the element can be significantly expanded. Furthermore, a 2×2 UWB CP array is designed based on this element. A gradient artificial magnetic conductor (GAMC) with a metal cone is adopted to realize both a low-profile ( 0.1×λ , where λ is the air-free wavelength at lowest frequency) and the high-gain radiation for the first time. To validate this novel configuration, this array is fabricated and measured. The measured bandwidth ( |S11|<−10 dB, AR < 3 dB) is approximately 92.3% (1.75–4.75 GHz). It also achieves a wide 3 dB gain bandwidth of 72.3%. Both the simulated and measured results demonstrate that this low-profile high-gain antenna array is promising for applications in wireless systems such as mobile satellite communication system.

The increasing number of Jakarta Special Province residents further increased the amount of land required for daily usages. In order to maintain and improve the economy, agricultural land-use continued to be converted into non-agricultural land-use. The reduced amount of agricultural land-use was able to increase the population pressure on said land, surpassing the land carrying capability. Analyzing the remaining land resources of Jakarta Special Province aimed to understand the changes in land-use, land carrying capability, the scale of land resources, and to determine the population pressure of the residents of Jakarta Special Province. The methods used in this analysis was to use secondary data, presented in the form of tables, graphs, and maps, as well as quantitative and qualitative descriptive analysis. In general, Jakarta Special Province had experienced a conversion of agricultural land-use into non-agricultural land-use (e.g. residential and industrial) between the year 2010 to 2018. The number of residents had exceeded the carrying capacity of Jakarta's land. This resulted from a growing need for non-agricultural land as well as the amount of population pressure, causing the unmet settlement needs.

Resolution of synthetic aperture radar is divided into two-dimensional space: Azimuth and range resolution. The range resolution is determined by the bandwidth of signal. Conventional synthetic aperture radar system uses multiplier to expand the bandwidth, however, the distortion in spectrum also are expanded. In this paper, the method for bandwidth widening using multi direct digital synthesizer blocks is designed and compared. We formulate signal parameters to widen bandwidth without multiplier. In addition, we confirm the wide bandwidth while maintaining minimal system clock. However, the number of blocks is not proportional to the signal quality. We derive the optimal number of blocks considering by the cost effectiveness and the signal quality.

Synthetic Aperture Radar (SAR) has the advantage of operating regardless of the cloud cover or a lack of light. This makes SAR a potential substitution for optical sensors in various ways. SAR images have been effectively used for detecting the various terrain changes, particularly in comparing the terrain before and after natural disasters. In this paper, we compare SAR images to measure the forest loss rate before and after the fire. we analyze the Gangwon-do forest fire which occurred in 2019. SNAP (Sentinels Application Platform) is used in this paper to process Sentinel-1. Pre-processing, post-processing, color manipulation, cropping image was used in the program. Based on the calculated loss rate, we expect that it can be used for other researches such as flood or debris flow. It would be more accurate by using SAR images.

West Sumatra is one of has big geothermal energy resources potential. Remote sensing technology can have a role in geothermal exploration activity to measure the distribution of land surface temperatures (LST) and predict the geothermal potential area. Main study to obtain the assessment of Landsat 8 TIRS (Landsats Thermal Infrared Sensor) data capability for geothermal energy resources estimation. Mono-window algorithms were used to generate the LST maps. Data set was combined with a digital elevation model (DEM) to identify the potential geothermal energy based on the variation in surface temperature. The result that were derived from LST map of West Sumatra shows that ranged from-8.6 C° to 32.59 C° and the different temperatures are represented by a graduated pink to brown shading. A calculated result clearly identifies the hot areas in the dataset, which are brown in colour images. Lima Puluh Kota, Tanah Datar, Solok, and South Solok areas showed the high-temperature value (Brown) in the range of 28.1 C° to 32.59 C° color in images which means that they possess high potential for generating thermal energy. In contrast, the temperatures were lower (Pink) in the north-eastern areas and the range distribution was from-8.5 C° to 5 C°.

In this paper, a new EBG based compact design of dual band UWB MIMO antenna is proposed. This MIMO antenna operates in Ku-band and K-band. It consists of four slotted-rectangular element antennas and it occupies a compact size of 60.72×56.72 mm2 . The existence of EBG enhances a-10 dB impedance bandwidth (VSWR ≤ 2) and it reduces mutual coupling. Based on the simulated numerical results, it is shown that the EBG based design has a 3.518 GHz of ultrawideband in Ku-band and a 3.699 GHz of ultrawideband in K-band, respectively. There is a 17.46 % bandwidth improvement in Ku-band. In addition, reducing the level of mutual coupling by using EBG technique reaches – 30 dB until – 70 dB along dual band. In addition, the presented design has very low ECC level, i.e., 0.003. This new proposed design has a good performance including low mutual coupling, compact size and ability to operate in dual band UWB. Copyright © 2020 Praise Worthy Prize S.r.l.-All rights reserved.

This research aims to design a Curved Microstripline Antenna Array using an optimal characteristics parameter. The empirical formula and numeric analysis were optimally applied to the satellite communication system in relation to the antenna's characteristics. The analysis result showed that a 2×2 array curved microstripline antenna parameter obtained, comprises of 0.59 VSWR, 0.28 Reflection Coefficient, and-11.06 dB Return Loss. Also, a 2×4 array, consists of 1.19 VSWR, 0.09 Reflection Coefficient, and-20.92 dB Return Loss, while in a 4×4 array, the Antenna Parameter consists of 1.14 VSWR, 0.07 Reflection Coefficient and-23.58 dB Return Loss. These three simulations and measurement are compared to design a Curved Microstripline Antenna Array with more optimal characteristics parameters that are fabricated and applied to obtain a better satellite communication system.

This paper presents a X-band circular polarization antenna with elliptic stripline resonators on glass epoxy substrates. An elliptic antenna provides high efficiency to microwave energy transmission. Glass epoxy substrate provides reduced fabrication cost compared to conventional Teflon substrates. Wideband directive gain 16.5 dB and 1dB axial ratio in bandwidth 10 % by the array of 16 antennas. The directive gain became lower by dielectric loss of the glass epoxy substrate compared to Teflon.

A strong earthquake with M 6.4 in 14 km shallow depth occurs in the Eastern of Taiwan. To clarify the land deformation model and area damage covered, the SAR data of Sentinel-1A/B in ascending and descending orbit extracted. The data is collected from coseismic and post-seismic. In processing SAR data, Differential Interferometry Synthetic Aperture Radar (D-InSAR) technique applied. The result presents significant deformation reach to 250 millimeters in line of sight (LOS) for ascending and descending orbit.

The earthquake of May 27th 2006 has caused drought to several water sources in Mangunan village. Hence, it needed a preliminary study on the hydrology condition in the aftermath of earthquake in Mangunan Village - Bantul. Methods to identify the hydrology availability and water need condition using data calculation discharge and geometric population growth. According to the measurement result in Mangunan Village, the actual water availability is 128,484 m3/day, which can cover the water requirement to fulfill the need of the people amounting to 657,75 m3/day. Although, in fact, the village potentially has enough water availability with the amount of 14.037,845 m3/day. So, a further research could be done to achieve a stable condition of the dynamic discharge. Groundwater conservation is very needed in this research area. In general, the dry region in the village needs to be planted with vegetation that are resistant to dryness in the region with shortage of water and also with plants that do not absorb much groundwater or soil mosturizer.

FR-4 and NPC-220AH substrates are used to design antennas with Multiband frequency. This research, therefore, aims to design varying performance Curved Microstripline Array Antenna, with optimized parameters. This was carried out with the difference substrate in the simulation program. In addition, the proposed antenna is analyzed to determine the return loss (S11 parameter), Voltage Standing Wave Ratio (VSWR), Gain, and Radiation Pattern. The result showed that the microstrip antenna design uses the dielectric substrate materials of varying constant values. In conclusion, this study suggests the use of cost-effective substrate materials.

The significant ground deformation occurred at Lombok Island due to the large scale of series Earthquake in shallow depth from July to August 2018. Extract the information of ground deformation on the study area, Differential Interferometry Synthetic Aperture Radar (D-InSAR) technique was applied. The observation supported by SAR satellite data of Sentinel-1A/B (C-band) 5.5 GHz provided by the European Space Agency (ESA). The satellite direction observation is from ascending and descending orbit with vertical transmit and vertical received (VV) polarization. The data acquisition is taken from July 2018 to August 2018 in three pairs before and after the earthquake hit the Lombok Island. Three zones have significant land deformation during the Lombok earthquake in 2018 namely zone A, zone B and zone C with 16 cm, 25.2 cm, and 28 cm uplift in the line of sight (LOS), respectively. The value carried out by comparing the two-close time acquisition before and after the earthquake. Finally, the result of D-InSAR processing validates by ground data observation taken from an optical image of airborne.

This paper was aimed at estimating the forest aboveground biomass (AGB) in the Central Kalimantan tropical peatland forest, Indonesia, using polarimetric parameters extracted from RadarSAT-2 images. Six consecutive acquisitions of RadarSAT-2 full polarimetric data were acquired and polarimetric parameters were extracted. The backscattering coefficient ( σ o ) for HH, HV, VH, and VV channels was computed respectively. Entropy (H) and alpha ( α ) were computed using eign decomposition. In order to understand the scattering behavior, Yamaguchi decomposition was performed to estimate surface scattering ( γ s u r f ) and volume scattering ( γ v o l ) components. Similarly following polarimetric indices were computed; Biomass Index (BMI), Canopy Structure Index (CSI), Volume Scattering Index (VSI), Radar Vegetation Index (RVI) and Pedestal Height ( p h ). The PolSAR parameters were evaluated in terms of their temporal consistency, inter-dependence, and suitability for forest aboveground biomass estimation across rainy and dry conditions. Regression analysis was performed between referenced biomass measurements and polarimetric parameters; VSI, H, RVI, p h , and γ v o l were found significantly correlated with AGB. Biomass estimation was carried out using significant models. Resultant models were validated using field-based AGB measurements. Validation results show a significant correlation between measured and referenced biomass measurements with temporal consistency over the acquisition time period.

In this research, the potential of L-band SAR data is evaluated for tropical peatland forest biomass estimation using polarimetric features and field data. For this, ALOS-2 full polarimetric data are acquired over central Kalimantan, Indonesia. Total 54 sampled plots (20m×20m) were established in the study site; diameter at breast height (DBH) and tree species of every tree were collected in each plot. Locally developed allometric equations were used to convert field data to biomass and plot level biomass, and the upscaling factor was applied to upscale plot level biomass to standard tones per hectare scale. Backscattering coefficient (σo) was computed for HH,HV,V H and V V polarization. Similarly, eigen decomposition was performed to extract: entropy (E), alpha (α), and anisotropy (A); also diversity indices were computed. Yamaguchi decomposition was performed to extract scattering behavior of forest in central Kalimantan. All polarimetric parameters were upscaled to one-hectare scale. Field data were divided into training plots (70 percent → 42 plots) and validation plots (30 percent → 12 plots). Nonlinear regression analysis was performed between polarimetric parameters and training plots. Perplexity, Shannon index, entropy, Gini Simpson index, index of qualitative inversion, Reyni entropy (order 2), σHV , alpha, σV V , and volumetric scattering component were found significantly correlated (ranging R2 from 0.67 to 0.49) with the field data. The corresponding nonlinear model was inverted, and biomass maps were computed for the individual model. The resultant biomass maps were validated using a validation set of referenced measurements. Perplexity, Shannon index, entropy, Gini Simpson index, index of qualitative inversion, Reyni entropy (order 2), σHV , alpha, σV V , and volumetric scattering exhibited a significant correlation between field biomass and predicted biomass computed using developed model. R2 for validation ranges from 0.95 to 0.81 with RMSE ranging from 13.59 Mgha−1 to 25.63 Mgha−1. The estimated biomass in study site ranges from 49.31Mgha−1 to 290.60 Mgha−1.

Natural resource abundance in South Kalimantan has been expected to optimize public services. The SDGs accomplishment requires an equitable implementation in economic, social, and environmental aspects. This research aimed to (1) discover the human and economic condition and (2) determine the development direction of South Kalimantan Province. It was based on institutional-secondary data that were processed in GIS softwaee and analyzed with both qualitative and quantitative approaches. The results showed that: (1) the human resources in South Kalimantan could accelerate regional development-however, some of the quelitative indicators are associated with poverty complicated by gender disparity-, while the land resources became increasingly limited due to intensive agricultural practices that caussd the rise of industrial and trade sectors; and (2) the development of South Kalimantan should improve people's perception of gender-related toptcs, recruit more medical workers, and reduce pressures on agrioultural land by switching into stable industrial activities.

Electromagnetic wave backscattering by corner reflectors in an anechoic chamber is studied using our developed computational tool. The tool applies the Finite-Difference Time-Domain (FDTD) method to simulate the propagation of the wave’s electric and magnetic fields. Experimental measurement in an anechoic chamber is also carried out as a comparison. The two results show agreement, including the finding that the backscatter intensity variation amongst the four circularly polarized modes is significantly smaller than the variation amongst the four linearly polarization modes.

Cloud classification is not only important for weather forecasts, but also for radiation budget studies. Although cloud mask and classification procedures have been proposed for Himawari-8 Advanced Himawari Imager (AHI), their applicability is still limited to daytime imagery. The split window algorithm (SWA), which is a mature algorithm that has long been exploited in the cloud analysis of satellite images, is based on the scatter diagram between the brightness temperature (BT) and BT difference (BTD). The purpose of this research is to examine the usefulness of the SWA for the cloud classification of both daytime and nighttime images from AHI. We apply SWA also to the image data from Moderate Resolution Imaging Spectroradiometer (MODIS) onboard Aqua and Terra to highlight the capability of AHI. We implement the cloud analysis around Japan by employing band 3 (0.469 μm) of MODIS and band 1 (0.47 μm) of AHI for extracting the cloud-covered regions in daytime. In the nighttime case, the bands that are centered at 3.9, 11, 12, and 13 µm are utilized for both MODIS and Himawari-8, with somewhat different combinations for land and sea areas. Thus, different thresholds are used for analyzing summer and winter images. Optimum values for BT and BTD thresholds are determined for the band pairs of band 31 (11.03 µm) and 32 (12.02 µm) of MODIS (SWA31-32) and band 13 (10.4 µm) and 15 (12.4 µm) of AHI (SWA13-15) in the implementation of SWA. The resulting cloud mask and classification are verified while using MODIS standard product (MYD35) and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) data. It is found that MODIS and AHI results both capture the essential characteristics of clouds reasonably well in spite of the relatively simple scheme of SWA based on four threshold values, although a broader spread of BTD obtained with Himawari-8 AHI (SWA13-15) could possibly lead to more consistent results for cloud-type classification than SWA31-32 based on the MODIS sensors.

Siak Regency is one of the areas in Indonesia that has peat areas. Events of forest fires occurring in Indonesia caused by the dryness of peatland attracted the attention of many parties to pay attention to this land as a serious matter. From this study, we found variations in soil moisture conditions around 11 - 50%, associated with soil content, the limiting pH parameter in peatland is about 3 to 4. With the approach of remote sensing microwave technology and field validation measurements by counting humidity, sample properties, it is known that the character of the peatland as well as produce the latest geological map for the distribution of peat and the region contained within the Regency of Siak.

Deforestation in peatland areas such as Kalimantan, Indonesia has been going on for decades. The deforestation has indirectly increased peatlands to become degraded and flammable. The Synthetic Aperture Radar (SAR) interferometry approach for identification of degraded peatlands can be performed using ALOS-2 PALSAR-2 data by converting land deformation data generated from SAR interferometry analysis into water table (WT) depth data using Wosten models. Peatlands with WT depth conditions of more than 40 cm are classified as degraded peatlands which are flammable. By using fire data from previous studies, this research confirms that identification of degraded peatlands using SAR interferometry approach by ALOS-2 PALSAR-2 is more reliable with high precision related to forest fires, with a precision level of 88% compared to 5% precision level using the WT depth monitoring system that has been installed in Central Kalimantan. The highest wavelength of ALOS-2 PALSAR-2 (L-Band) data can resolve the limitation due to temporal and volumetric decorrelation, compared to C-Band and X-Band satellite data. The combination methods of SAR interferometry approach and the real-time WT depth monitoring system to identify degraded peatlands can be more efficient, faster, and accurate. The advantage of this research result shows that SAR interferometry analysis can reach blank spot areas that are not covered by the observation station of WT depth monitoring system. It also gives a benefit as a guide to select precise locations of observation stations related to degraded peatland and forest fire.

This paper presents a new design technique to reduce the thickness of the transmitarray (TA) panel while maintaining 360o phase shift range. Two types of unit cells, the receive-transmit unit cell and the frequency selective surface (FSS) unit cell, are placed in the same aperture. Comparing to the existing ultra-thin TA designs of similar panel thickness, the presented TAs do not suffer from the phase quantization loss and achieve better aperture efficiency. This study proves that it is viable to mix different types of TA unit cells to design a TA. The developed TA shows better gain than a homogeneous TA using the same elements and improved the overall efficiency by 60%. To verify the design concept, one TA with central frequency at 13.3 GHz was designed, fabricated and measured. The measured gain is 21.3 dBi and the calculated aperture efficiency of the TA is 37.9%.

The development of a 2×2 array antenna with sequential rotation network feeding for X-band data communication is presented. The minimum requirement of proposed antenna is having 400 GHz impedance bandwidth under -10 dB with working frequencies at 8.0 GHz-8.4 GHz. The proposed antenna will be developed in circularly polarized mode. Thus, the axial ratio must be under 3dB at the desired frequencies. To ensure the antenna design fulfilling all the minimum requirements, some techniques are implemented, for example, triangular truncation factor, ring slot with ellipse shape in the middle of patch, and sequential rotation with relative phases 0 degrees, 90 degrees, 180 degrees, 270 degrees. Then the radiator of antenna is formed by a circular shape. The proposed antenna could fulfil satisfied results. The impedance bandwidth of antenna is obtained 1.8 GHz (7.5 GHz-9.3 GHz). The simulated gain reached 12.5 dBic at the center frequency and the axial ratio bandwidth is 1.17 GHz (7.3 GHz-8.47 GHz). The antenna design is printed at an NPC H220A dielectric substrate with the dielectric constant of 2.17, the thickness of 1.6 mm, and the sizes of 60.92 mm x 60.92 mm.

This paper presents the development of circularly polarized microstrip antenna using triangular truncation with axial ratio enhancement for X-band communication of Synthetic Aperture Radar (SAR) system. It is well-known that the axial ratio is ome of most essential characteristics in term of antenna with circular polarization. Many methods had been reported in attempting to generate circular polarization, one of them is by utilizing a truncation technique. Thus, in this work a novel truncation shape using a triangular truncation is introduced. The required antenna dimension is less than 40\\mathbf{mm}\\times 40\\mathbf{mm}. A single patch antenna is developed by two layers of NPC-H220A substrate with each thickness of 1.6mm and dielectric constant of 2.17. The feeding line is positioned at the middle part between the first layer and the second layer. Here, the proposed antenna attains a decent circular polarization. The axial ratio obtained is 0.49GHz with the low frequency stands at 7.9GHz and the high frequency stands at 8.44GHz. Meanwhile, the minimum requirements of antenna design are 0.4GHz bandwidth with the resonant frequency at 8.2GHz.

This paper presents a novel hybrid design technique to minimize the number of layers of the transmitarray (TA) panel while maintaining 360° phase shift range. Two types of unit cells, the receive-transmit unit cell and the frequency selective surface (FSS), are placed in the same aperture. The resulting TA panel is very thin but does not sacrifice the radiation efficiency of the array. The receive-transmit unit cell is an aperture-coupled square patch, and the FSS unit cell is a novel wide bandpass FSS. Both types of unit cells have three conductive layers and are printed on two substrates with a total thickness of 0.07λ0. The developed hybrid TA shows better gain than a homogeneous TA using the same elements. Meanwhile, it has comparable radiation performance but with a much lower profile compared to the conventional FSS-based TA designs that use several substrates separated by air layers. To verify the design concept, two hybrid TAs of different sizes with central frequency at 13.3 GHz were designed and fabricated. The measurements show that the TAs have at least 6.7% 1 dB gain bandwidth and higher than 30% aperture efficiency. Compared to the existing ultrathin designs of similar panel thickness, the presented TAs do not suffer from the phase quantization loss and achieve better or similar bandwidths.

A novel unsupervised image classification algorithm which based on the sparse representation theory for polarimetric synthetic aperture radar (PolSAR) image is introduced in this paper. The algorithm conjunctively uses sparse representation-based classification (SRC) theory, dictionary updating method, and label smoothness constraint to update class labels. The unsupervised H/α/A Wishart classification method is introduced to provide the preliminary classification result, from which the initial dictionary and class labels can be extracted. An energy function is defined, and it contains two terms. The first term is based on the sparse representation theory. It reflects the cost of assigning different class labels to a pixel. The second term is label smoothness constraint. It constrains that class labels of neighbouring pixels in flat regions should be the same. By alternately minimizing the energy function, two unknown variables, dictionary and class labels are updated. Optimized class labels are the outputs to compose the final classification result. Extensive experimental results for three PolSAR datasets are analysed to verify the validity of the proposed method. Comparison with other unsupervised/supervised classification methods indicates its superiority.

This paper proposes development and performance analysis of wideband pyramidal horn antenna equipped with binomial polarizer to produce circularly polarized waves. The proposed antenna which is designed and optimized to operate at the X-band frequency is intended to be used for circularly polarized synthetic aperture radar (CP-SAR) application. The optimized antenna design is fabricated using 3D printing technology for fast, low cost and light weight which is very suitable for small platform of CP-SAR sensor. The performance of manufactured antenna has demonstrated the fractional impedance bandwidth of 26% for S11 below-10dB, the axial-ratio bandwidth of 6.2% below 3dB, and the gain achievement up to 12dBic at the desired working frequency.

In this paper, a soil moisture retrieval from full-polarimetric synthetic aperture radar (SAR) data is investigated for sparsely vegetated soil surfaces. An improved retrieval method adapting the variations in vegetation is proposed by incorporating the generalized volume model into the polarimetric two-scale two-component model (PTSTCM). The feasibility of the method, termed as the adaptive PTSTCM, has been tested for tropical peatland sites in Indonesia which exhibit a variety of sparse vegetation cover on soil after land clearing activities. The in situ data were collected in March and August 2017 with the time domain reflectometry (TDR) probe for a total of 18 sample points over 11 regions. The method was applied to ALOS-2 L-band quad-pol SAR data that were acquired simultaneously with field measurements. We compared the results between the proposed adaptive PTSTCM and the original PTSTCM that utilizes specific types of volume model (i.e., randomly, horizontally, and vertically oriented volume models). Scatterplots of estimated versus measured in situ results reveal that the adaptive PTSTCM yields a root-mean-square error (RMSE) of 5.1vol.% and inversion rate of 35.0% and 58.5% for March and August data, respectively, which are found to be superior to those of the original PTSTCM.

Chiba University proposed and developed airborne C band circularly polarized synthetic aperture radar (CP-SAR) for environment and disaster monitoring. This paper explains concept, system configuration, RF system and antenna, and flight test of CP-SAR in Hinotori-C2 (Firebird-C2) mission onboard CN235MPA aircraft on 14-15 March 2018 at Indonesia. The result of flight test depicts full polarimetric CP images that shows good performance of CP-SAR. The assessment of CP image analysis, and novel image classification using axial ratio (AR), ellipticity (ϵ), and polarization ratio (ρ) are discussed.

In this research, a Flood Warning System is designed based on Water Level Data image obtained by a simple web camera. The system processes the output data from the water level image into tables and then connect to the flood map database to select the corresponding map to be displayed as a flood prediction image with a GIS program. The system processes the data in real time to provide public users with an accurate flood area prediction. By using this system, user can expect the area which will be affected when the water level rises to allow peoples that live near the affected area to evacuate or at least to prepare for the upcoming flood. This kind of early warning system is expected not only will save the lives of people who live near the affected area but also save their valuables from the flood disaster. The flood area is segmented from LiDAR data at 1 m intervals and the water level is recorded at 10 cm intervals. The resulting area obtained from elevation data is considered as the boundary of the maximum extent of the flood. Each corresponding map layer is linked to specific water level recorded by the camera.