• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.5
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• pp.561-568
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• 2014

The Republic of Korea Army is using R-NAD of MIL-STD-188-220 as a Media Access Control protocol. Under urgent situations, almost all stations transmit data frames and then the network will reach a saturation state. Several articles have been devoted to the study of R-NAD performance. However, most of them focus on comparing the performance of some NADs using network simulation tools. We propose an analytical model to compute the throughput of R-NAD under the assumption of a network traffic saturation. Analytical results were verified by Monte Carlo methods. We have shown that the performance of a success probability and an average idle time remains almost unchanged as the total number of stations increases. We have also shown that Type 1/2/4 operation mode outperforms Type 3 operation mode in throughput. The results showed that the system with a squelch detection achieved a better performance than the one without it. The longer DATA time had a higher throughput.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.894-897
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• 2008

This paper analyzes the throughput performance of a selective repeat (SR)/automatic repeat request (ARQ) scheme to transmit packet data in burst home network channel. To combat the high degree of error caused by transmission of home network data a robust error control scheme is a necessity. Basically, error control schemes can be divided in two categories: ARQ schemes and forward error correction (FEC) schemes. ARQ schemes are often used for reliable data transmission. The performance of packet transmission using SR-ARQ schemes for bursty channels is analyzed and simple analytical expressions of its throughput are presented. Theoretic analysis and numerical results indicate that a small number of packet sizes can get good performance in bursty home network channel.

• Journal of Internet Computing and Services
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• v.10 no.1
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• pp.51-61
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• 2009

This paper analyzes the throughput of DCF protocol at the MAC layer in the 802.11a wireless LAN. The throughput of DCF protocol is related on probability of backoff, depends on retransmission of each terminal. This paper applied to nonmarcov discrete model for each terminal BER in the base station versus the packet throughput is progressing with the data rate of 6,12,24,54 Mbps, We find the fact that the less the data rate be the higher the throughput. We also find from the throughput calculation by means of traffic intensity in OFDM wireless LAN.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.6
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• pp.1410-1418
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• 2007

This paper analyzes the throughput of DCF protocol at the MAC layer in the 802.11a wireless LAN. The throughput of DCF protocol is related on probability of backoff, depends on retransmission of each terminal. This paper applied to nonmarcov discrete model for each terminal BER in the base station versus the packet throughput is progressing with the data rate of 6,12,24,54 Mbps, We find the fact that the less the data rate be the higher the throughput. We also find from the throughput calculation by means of traffic intensity in OFDM wireless LAN.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.18 no.8
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• pp.2281-2297
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• 2024

Employing multiple drones as a swarm to complete missions can sharply improve the working efficiency and expand the scope of investigation. Remote UAV swarms utilize satellites as relays to forward investigation information. The increasing amount of data demands higher transmission rate and complex field network coding (CFNC) is deemed as an effective solution for data return. CFNC applied to UAV swarms enhances transmission efficiency by occupying only two time slots, which is less than other network coding schemes. However, conventional CFNC applied to UAVs is combined with constant coding and modulation scheme and results in a waste of spectrum resource when the channel conditions are better. In order to avoid the waste of power resources of the relay satellite and further improve spectral efficiency, a CFNC transmission scheme with MPSK modulation is proposed in this paper. For the proposed scheme, the satellite relay no longer directly forwards information, but transmits information after processing according to the current channel state. The proposed transmission scheme not only maintains throughput advantage of CFNC, but also enhances spectral efficiency, which obtains higher throughput performance. The symbol error probability (SEP) and throughput results corroborated by Monte Carlo simulation show that the proposed transmission scheme improves spectral efficiency in multiples compared to the conventional CFNC schemes. In addition, the proposed transmission scheme enhances the throughput performance for different topology structures while keeping SEP below a certain value.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.703-704
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• 2009

• Journal of Navigation and Port Research
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• v.40 no.2
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• pp.57-65
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• 2016

The port throughput situation has changed since the 2008 financial crisis in the US. Therefore, we studied the situation, accurately estimating port traffic of Korean port after the 2008 financial crisis. We ensured the proper port facilities in response to changes in port traffic. In the results of regression analysis, Korean GDP and the real effective exchange rate of Korean Won were found to increase the container throughput in Korean and Busan port, as well as trade volume with China. Also, the real effective exchange rate of Korean Won was found to increase the port transshipment cargo volume. Based on the ARIMA models, we forecasted port throughput and port transshipment cargo volume for the next six years (72 months), from 2015 to 2020. As a result, port throughput of Korean and Busan ports was forecasted by increasing annual the average from about 3.5% to 3.9%, and transshipment cargo volume was forecasted by increasing the annual average about 4.5%.

• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.4
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• pp.587-594
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• 2022

This paper analyzed radio link throughput performance by applying radio link simulation and test equipment because there is limit in train filed test in 420 km/h high speed environment. According to the radio performance analysis, the throughput performance is slightly degraded in QPSK and 16QAM modulation schemes. But throughput performance is highly degraded in 64QAM modulation scheme.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.9
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• pp.1891-1897
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• 2009

This paper describes the optimization of the spectrum sensing in terms of the throughput of the cognitive radio (CR)system. The conventional rapers do not describe the optimization problem of the spectrum sensing by considering the channel search and channel move of the CR system to be caused by the appearance of the incumbent user. However this paper evaluates the throughput of the CR user by considering the situations such as the channel search and channel move additionally. Also, this paper suggests the sensing structure being separated the data receiver from sensing receiver, and compares the sensing performance for the same receiver structure of sensing and communication with that for the separated sensing receiver in terms of the throughput of the CR user. The numerical result demonstrates that the performance of the throughput efficiency is improved by the proposed sensing receiver to be separated from the data communication path.

• Journal of the Korea Society for Simulation
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• v.21 no.2
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• pp.51-58
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• 2012

In IEEE 802.16j MMR protocol, two modes about usage of RS are proposed; one is transparent mode to enhance data throughput and the other is non-transparent mode to extend coverage. In this paper, we focus on non-transparent mode and find that the mode can also improve data throughput. Therefore, we analyze data throughput on various RS topology and their extended coverage area by simulation in IEEE 802.16j non-transparent mode. We also compare the simulation results with the single MR-BS system of which coverage is extended by higher transmission power. From the comparisons of simulation results, we see that higher throughput can be obtained in the proposed non-transparent mode.