• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.4
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• pp.489-496
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• 2018

In this paper, a performance comparison of dynamic TDMA and fixed TDMA in tactical data link system is conducted. The performance metric include: delay, queue size and system throughput. To perform comparison of two TDMA schemes, we adopt the modified M/D/1 queueing model. Computer simulation is also performed to verify conducted analytical results.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.6A
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• pp.820-831
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• 1999

In this paper, we have compared the performance of a D-TDMA protocol with that of a CDMA protocol, in radio access system for integrated voice/data services.The D-TDMA protocol is based on a generic dynamic channel assignment approach to be followed a combination of “circuit mode” reservation for voice calls, along with dynamic first-come-first served assignment of remaining capacity for data messages. In the CDMA protocol, we have used the voice activity detection to reduce the interface power of other mobiles in internal and external cells, and analyzed the interference power ratio. Also we have computed BER(Bit Error Rate) by using this interference power ratio and evaluated voice blocking probability(voice packet loss probability) and data transmission delay, according to average data length and average data arrival rate.We have found the CDMA protocol achieves comparatively higher performance for short data length, regardless of data arrival rate. Otherwise, the data transmission delay of D-TDMA protocol is shorter than that of the CDMA protocol for long data message.

• Journal of the Korea Institute of Military Science and Technology
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• v.16 no.6
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• pp.789-796
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• 2013

Next Generation Weapon system from the center of the platform to share information in real-time Network Centric Warfare(NCW: Network Centric Warfare) has been changed. Data link system is defined as a network. That is, all in real-time battlefield information is to enable sharing. Data link system is classified as a precision strike, Monitoring/control, control of a Patriot missile battery systems. These systems are most effective in a Joint warfare and precision strike. Data Link Systems(Data Communications) implementation is accomplished by using the KDLM(Korean Data Link Modem) and Radio Transceiver. KDLM is operated in conjunction with the legacy Radios(re-using fielded HF/VHF/UHF radio systems). In this paper, we describe in terms of KDLM system design. In this paper, the proposed design structure is how to effectively interact with legacy various radio. First, The results provide an analysis of that Dynamic TDMA system and apply modem structure. Radio characteristics data are necessary for an effective TDMA system design. This article analyzes the test results and describes the structure to improve the receive performance.

• Journal of the Korea Institute of Military Science and Technology
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• v.23 no.4
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• pp.371-380
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• 2020

Video is principal information that facilitates commander's immediate command decision. Due to fading characteristics of radio link, however, it is difficult to stably transmit video in a multi-hop wireless environment. In this paper, we propose a MANET structure composed of a link adaptive routing protocol and a TDMA MAC protocol to stably transmit video traffic in a ultra-narrowband video streaming network. The routing protocol can adapt to link state change and select a stable route. The TDMA protocol enables collision-free video transmission to a destination using multi-hop dynamic resource allocation. As a result of simulation, the proposed MANET structure shows better video transmission performance than proposed MANET structure without link quality adaption, AODV with CSMA/CA, and OLSR with CSMA/CA structures.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.261-262
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• 2008

TD-SCDMA is considered as an innovative Chinese 3G technology adopted by the ITU for the IMT-2000 family. TD-SCDMA combines TDMA and CDMA components to provide more efficient use of radio resources. However, the downlink scheduler of TD-SCDMA should transmit data packets with the initial configuration and cannot change the configuration dynamically. Therefore, in this paper, we propose an enhanced channel allocation, by which mobile terminals can share the downlink channelization codes dynamically.