• Journal of Advanced Navigation Technology
• /
• v.20 no.6
• /
• pp.528-538
• /
• 2016

In this paper, an extend kalman filter based relative navigation algorithm is proposed for Link-K based relative navigation. Link-K is a tactical data link system for joint operation capability upgrade of ROK forces. Link-K is inter-operable with Link-16 and transmit and received information of operations and target. In Link-K communication channel, PPLI message including transmitter position and TOA measurement can be used for relative navigation. Therefore Link-K based relative navigation system can be operated. In this paper, software based simulations were carried out for operational feasibility test and performance verification as error factors of proposed Link-K based relative navigation system.

• Journal of Information Technology and Architecture
• /
• v.11 no.1
• /
• pp.11-23
• /
• 2014

Kill Chain is getting attention due to North Korea's recent nuclear test and missile launches and has emerged the need for an early build up. In order to build a materialized kill chain, you should review the unique kill chain to support operations effectively using various sensors and striking weapon system. Especially, you need a suitable network to reduce a reaction time against the enemy attack under joint operations environment etc. Currently there are many communication ways(e.g. data link, voice, video and text message) used in operations through satellite, wired and wireless and so on. Now, this paper contains analysis on various means for target information exchange which are used in the kill chain. And appropriate network of the kill chain for target information transmission is addressed to confirm feasibility of its alternatives, which is developed using AHP(Analytic Hierarchy Process). Finally, this paper is suggesting network and means of its building up for target information transmission of kill chain which can be implemented under the situation of joint battle field.

• Journal of Advanced Navigation Technology
• /
• v.14 no.5
• /
• pp.625-631
• /
• 2010

In this paper, robustness performance of SNUR message is compared with those of existing ones, RTCM(Radio Technical Commission for Maritime Services) v2 MT(Message Type) 18/19 and MT 20/21 under a poor broadcast condition such as temporary data loss or disconnection We defined the temp oral data loss as 2 second delay and reconnection after disconnection as 7 second latency, and then evaluated its robustness for each latency case by double differentiating the observables. Our result shows that SNUR protocol method can reduce the latency error of the existing RTCM messages by 30~60%. Moreover, a rover using SNUR message, whose latency error is bounded within 1/4 L1 wave length, can figure out its own fixed position continuously in spite of 7 second disconnection, while the other using RTCM message, whose error is larger than half wave length, cannot keep its previous fixed solution.

• Journal of Advanced Navigation Technology
• /
• v.22 no.5
• /
• pp.367-374
• /
• 2018

A trajectory-based scheduling system is proposed for air traffic management using next generation aviation data communication link. Based on the service concept of 4-dimensional trajectory data link (4DTRAD) using air traffic serveices (ATS) datalink Baseline 2, a procedure for trajectory-based operation of an en-route flight is established and described in detail. To mitigate air traffic controllers' workload which might be caused by various and complicated data utilization, a prototype of the scheduling system, which predicts the aircraft trajectory based on the flight intents received by air traffic service system and provides advisory information for air traffic control, was developed. The simulation environment for trajectory based operation was built to validate the scheduling functionality of the prototype.

• Journal of IKEEE
• /
• v.24 no.1
• /
• pp.72-80
• /
• 2020

This paper describes the design and fabrication of a BUC(Block Up-converter) which is a component of a FST (Flyaway Satellite Terminal), one of the ET(Earth Terminal) of the military satellite. BUC is physically composed of an up-converter module, a high power amplifier module, a receive band suppression filter, a housing, and a cable assembly. It was designed using simulator AWR to satisfy the electrical characteristics of BUC's such as maximum output power, gain, unwanted signal, and intermodulation. The maximum output power and gain characteristics were measured at 43.4dBm and 51.8dB, respectively. The unwanted wave and intermodulation characteristics were -73.5dBc and -31.9dBc, respectively. Of the electrical requirements of Table 1, not only the above four but also all of the items were confirmed to be satisfied.

• Journal of IKEEE
• /
• v.24 no.1
• /
• pp.81-89
• /
• 2020

This paper describes the design and fabrication of a LNB(Low Noise Block downd-converter) which is a component of a FST(Flyaway Satellite Terminal), one of the ET(Earth Terminal) of the military satellite. LNB is physically composed of an down-converter module, a low noise amplifier module, a transmit band suppression filter, a isolator, a housing, and a cable assembly. It was designed using simulator (AWR) to satisfy the electrical characteristics of LNB's such as gain, noise figure and unwanted signal. The gain and noise figure characteristics were measured at 61.4dBm and 1.37dB, respectively. The unwanted wave was measured at -66.79dBc. Of the electrical requirements of Table 1, not only the above three but also all other items were confirmed to be satisfied.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.3B
• /
• pp.100-111
• /
• 2008

In this paper, to support a QoS level appropriate for the user in Wireless Home Network based Wireless LAN, we propose a QoS support architecture which includes Wired Network and Wireless Network. Actually, an important problem to support QoS in Wireless Home Network is approached not only on a MAC level in Wireless LAN but on a integrated method to combine Network layer with Datalink layer. Applying the integrated QoS support method. It is possible to provide QoS support architecture using a Wireless LAN terminal with a minimum changing, the proposed scheme has advantage of QoS support method, which is more superior than a existing scheme to support QoS in MAC level of Wireless LAN. Simulation results that overall performance of the proposed scheme can be improved.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.10 no.12
• /
• pp.1315-1320
• /
• 2015

In this paper Communication data link equipment on a high speed-hopping method to use the frequency resources efficiently for the frequency environment is introduced such as sensing techniques, using the same frequency band by using the received two-channel technique and the receive filter bank unit applied to be shared with other equipment such as radar and so on. The real-time measurement and analysis were operated for measurement the frequency environment of the operating band in advance. and primarily equipment to develop is analyzed how the interference effect to the radar minimize the operation of radar equipment. In reverse, to use the same frequency band the methods such as frequency sharing techniques are presented in this paper. Finally, by design of the main items of the RF transceiver NF, transmission output, and a simulation of the IMD, such as whether the key is verified prior to meet specifications.

• Journal of IKEEE
• /
• v.21 no.4
• /
• pp.338-347
• /
• 2017

This paper describes the design and fabrication of a high power amplifier which is a component of TDL(Tactical Data Link) aircraft terminal. We applied high-speed frequency hopping technology, cognitive radio technology, and receive filter bank technology to efficiently use limited frequency resources with radar and other communication equipment using the same frequency band. The high-power amplifier is physically composed of a transmitter, a receiver, a mechanical part, and a cable assembly, and is designed to meet temperature characteristics and electrical characteristics such as maximum transmission distance and reception sensitivity. Modeling and simulator were used to satisfy the requirement of high power amplifier. The transmit power and the noise figure were measured at 50.02dBm and 2.682dB, respectively. It was confirmed that all the required specifications were satisfied in the electrical characteristics test and the environmental characteristic test.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.41 no.10
• /
• pp.1210-1220
• /
• 2016

As modern warfare has changed into network centered, the ability to share situational awareness among allies become a core competency for performing operational missions. In an airborne environment, it uses a tactical data link such as Link-16 for shared situational awareness. There exist problems when it shares situational awareness over the existing data link that can not allocate slots dynamically or that can not change the number of a slot to be allocated. In addition, there was a problem that can not share this failure so that failed to improves situation awareness because of finite time slot resources. In this paper, we accommodate dynamic slot allocation and changes of slot allocation with mixed structure of TDMA (time division multiple access) and random access. We propose a technique that can be used when available slots are exhausted, and a load balancing method to prevent slot allocation delay when slot requesting or message sending is concentrated on a single subframe.