• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.6
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• pp.929-938
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• 2000

A summary of the development and verifications of a computer code being developed at Pohang University of Science and Technology (POSTECH) for calculating the radar cross section(RCS) of complex targets is presented. The complex targets are modeled in terms of patches and wedges. This code utilizes physical optics, physical theory of diffraction and shooting and bouncing rays method to calculate the RCS of complex targets. For the verification of the RCS prediction code, a simple-shaped scale-model was manufactured and the RCS was measured at the POSTECH compact range. The obtained RCS was processed to give frequency-domain RCS patterns and ISAR images. The predicted RCS shows good agreement with measured one. The RCS prediction methods presented here are applicable to stealth design and target recognition.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.1 s.116
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• pp.31-36
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• 2007

In the RFID system, one of the important criteria of tag antenna performance is the detection distance. The most important factor determining the detection distance of the tag antenna is the Radar Cross Sections(RCS). In this paper, we propose a method to simply measure the RCS of the RFID tag antenna using two reader antennas(Tx and Rx) and a network analyzer. We estimate RCS' from the RCS equation based on the measured $S_{21}$ using the network analyzer. We compare the measured $S_{21}$ values with the calculated $S_{21}$ values and the simulated $S_{21}$ values using EM simulator. The used tag antennas are two kinds of dipole-type, metal-type, and an inductively-coupled type ones. In case of the dipole type, the measured, simulated and calculated values of the RCS are almost the same. In case of other types, we obtain the measured RCS values with a difference of about 3 dB.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.9
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• pp.840-846
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• 2011

In this paper, reflection and RCS characteristic of the EGS(Electromagnetic Gradient Surface) due to incident angle and polarization is analyzed. Incident angle, ${\theta}_i$, is rotated from $0^{\circ}$ to $50^{\circ}$ with $10^{\circ}$ steps and perpendicular and parallel polarization of incident wave are also considered each incident angle. Reflection and RCS characteristic is not much affected by variation of polarization for normal incidence(${\theta}_i=0^{\circ}$). Reflection pattern has different characteristic due to variation of incident angle and polarization but the EGS has about 2 dB of RCS difference due to polarization in RCS characteristic.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.5
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• pp.77-82
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• 2016

Web developers have had difficulties in using Rich Communication Service-e(RCS-e) on their applications because of complicated protocols and closed interfaces. In order to vitalize the use of RCS-e, we need a RCS Application Program Interface(API) which has simple protocols and can be accessed easily. This paper presents the web-based Open API Framework for the RCS-e presence feature. A system architecture for the framework is defined. Call flows for the presence feature between the framework and other nodes are defined. Also, one of the call flows is illustrated to explain how to convert web-based requests to RCS-e requests. Finally, performance evaluation proves that the framework does not add any loads to the existing network infrastructure.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.5
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• pp.593-600
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• 2014

In this paper, Radar cross section (RCS) calculations of advanced naval vessels model with RCS reduction methods are simulated and RCS results are discussed. Especially, this paper are mainly focusing on the facts influencing on RCS, the ways minimizing RCS and material characteristics of RCS changing-rate. RCS analysis results are given for a DDG-1000 type advanced naval vessels, which show that as the elevation angle increased 10 degree, the mean RCS value increased 23.91 dBsm. Also, as the superstructure angle increased 6 degree, the mean RCS value reduced 1.27 dBsm. Finally, the radar absorbing material attachment at the front and back superstructure have been reduced 2.27 dBsm in terms of mean RCS value.

• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.4
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• pp.429-436
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• 2018

The RCS value of maritime ship is indicator of ship's stealth performance and it should be particularly measured for navy ship to ensure survivability on the battlefield. In the design phase of the navy ship, a RCS prediction should be performed to reduce RCS value and achieve ROC(Required Operational Capability) of the ship through configuration control. In operational phase, the RCS value of the ship should be measured for verifying the designed value and obtaining tactical data to take action against enemy missile. During the measurement of RCS for the ship, ship motion can be affected by roll and pitch in accordance with sea state, which should be analyzed into threat elevation from view point of enemy missile. In this paper, we propose a method to measure and analyze RCS of ship in 3-dimensions using a ship motion measuring instrument and a fixed RCS measurement system. In order to verify the proposed method, we conducted a marine experiment using a test ship in sea environment and compared the measurement data with RCS prediction value which is carried by prediction SW($CornerStone^{TM}$) using CAD model of the ship.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.6
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• pp.581-588
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• 2015

In this paper, we researched that setting standard for RSC(Radar Cross Section) of naval surface ship could be determined and considered in various ways on ship's survivability, technical building feasibility, operation and so on. This study presented fundamental capacity on anti-ship missile, radar, flight and so no and the procedure to set of target/standards for RSC. The RCS standards is good at setting low as low as to improve survivability aspect, but because we should consider effect, technical limit, cost etc, this paper analyzed necessary elements to set standard than to suggest specific number and suggested procedure to set standars according to suggest the boundary of RCS.

• International Journal of Aeronautical and Space Sciences
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• v.8 no.1
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• pp.54-65
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• 2007

Parameter optimization technique is applied to planning UAVs(Unmanned Aerial Vehicles) path under artificial enemy radar threats. The ground enemy radar threats are characterized in terms of RCS(Radar Cross Section) parameter which is a measure of exposure to the radar threats. Mathematical model of the RCS parameter is constructed by a simple mathematical function in the three-dimensional space. The RCS model is directly linked to the UAVs attitude angles in generating a desired trajectory by reducing the RCS parameter. The RCS parameter is explicitly included in a performance index for optimization. The resultant UAVs trajectory satisfies geometrical boundary conditions while minimizing a weighted combination of the flight time and the measure of ground radar threat expressed in RCS.

• International Journal of Internet, Broadcasting and Communication
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• v.11 no.1
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• pp.8-16
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• 2019

As smartphone users grow, mobile operators are trying to standardize and commercialize Rich Communication Suite (RCS), which is a next-generation messaging service, so that it can replace legacy messaging services. However, it is not enough to spread RCS widely to the users only by publishing an RCS app. To increase the use of RCS, a web-based open API for common RCS capabilities is needed. By using the API, Internet-based developers can create applications that make use of the RCS capabilities with less effort and time. This paper proposes a lightweight Comet-based open API to allow mobile operators to expose useful information and capabilities to application developers. The system architecture of the open API framework and call flow between relevant nodes are defined. In addition, examples of protocol translations on the framework are provided.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.5
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• pp.576-584
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• 2014

In this paper, a study on the optimization of fuzzy classifier using radar cross section(RCS) values is presented to classify shell-shaped targets. Method of moments(MOM) is exploited to construct RCS database of generic shell-shaped targets in uniform angular intervals. Relative orientations are estimated from various flight scenarios of shell-shaped targets, and associated RCS values are interpolated from the generated RCS database with uniform angular intervals. Initial membership functions are determined using the interpolated RCS values, and particle swarm optimization(PSO) is utilized to optimize the membership functions of the fuzzy classifier in terms of probability of correct classification.