• Proceedings of the IEEK Conference
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• 2001.06b
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• pp.101-104
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• 2001

In this paper, we have analyzed algorithm about physical layer, data link layer and MAC layer of out-of-band specified in the DVS 178 and designed architecture of Out-of-band processor. Out-of-band processor extracts session key information from EMM packet to descramble MPEG-2 TS packet scrambled. Also, analyze EAS Packet including emergency alert information to provide emergency communications such as national emergency. In this paper, we have implemented prototype board for out-of-band processor.

• Journal of Broadcast Engineering
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• v.17 no.6
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• pp.990-1003
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• 2012

In this paper, the possibility and necessity of the digital broadcasting propulsion in AM and FM is presented based on DRM and DRM+ transmission modes, They are the members of series technological family in digital radio development. As the frequency utilization, the application of DRM+ is flexible in any mode such as IN-BAND or OUT-OF-BAND. When the digital audio broadcasting is planned at LOW-VHF bandwidth such as TV channel No.5 and NO.6 being adjacent to FM band and OUT-Of-BAND DRM+ technology is applied, there is no collision and jamming. Particularly, in the IN-BAND Hybrid mode, it is mentioned that there was the difficulty problem for multiple SFN transmitters uses. Not like the IN-BAND mode the OUT-OF-BAND mode lets multiple transmitters, because neighbor transmitters do not interfere each other. Digital transmitter can be combined with the existing FM transmitter. The intensity of power and size of area can be easily determined according to local broadcasters' condition. And the OUT-OF-BAND mode is advantageous for AM/FM integration in digital radio receiver manufacturing, which makes the conversion schedule much shorter.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.7
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• pp.2212-2230
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• 2014

Cognitive radio (CR) users, known as secondary users (SUs), should avoid interference with primary users (PUs) who own the licensed band, while trying to access it; when the licensed band is unused by the PUs. To detect PUs, spectrum sensing should be performed over in-band channels that are currently in use by SUs. If PUs return to access the band, SUs need to vacate it, disrupting the SUs' communication unless a non-utilized band is discovered. Obtaining a non-utilized band in a short period facilitate seamless communication for SUs and avoid interference on PUs by vacating from the channel immediately. Searching for a non-utilized band can be done through proactive out-of-band (OB) sensing. In this paper, we suggest a proactive OB sensing scheme that minimizes the time required to discover a non-utilized spectrum in order to continue communication. Although, the duration spent on OB sensing reduces the throughput of the CR networks that can be achieved on band being utilized, the lost throughput can be compensated in the new discovered band. We demonstrate that, the effect of our proposed scheme on the throughput owing to OB sensing is insignificant, while exhibiting a very short channel discovery time.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.2
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• pp.146-150
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• 2017

In OFDM system, the out-of-band radiation of ensemble interferes with the adjacent ensemble and result in the reduction of receiving performance. So the reduction scheme of out-of-band radiation is very important. In this paper, a time-domain windowing method to reduce the out-of-band radiation is considered to DAB systems. We adopt the considered method to T-DMB(DAB mode-1) and AT-DMB Systems, and we get about 3-dB gains of out-of-band radiation. And also we show that the considered method doesn't reduce the BER performance.

• Proceedings of the IEEK Conference
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• 2000.11a
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• pp.393-396
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• 2000

Repeater Duplexer of 800MHz band consists of 4pole transmitter band pass filter, receiver band pass filter and branch circuit. Circuit parameter of Duplexer such as coupled capacitance of equivalent circuit was drawn out and used to coupled line characteristics impedance (Zoo, Zoe) that satisfied resonator condition and attenuation condition. Simulation was carried out by the ADS(Advanced Design System) were obtained good attenuation characteristics (869~894MHz： 65㏈(Min.),824~349MHz： 65㏈(Min.)

• Current Optics and Photonics
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• v.2 no.6
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• pp.629-634
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• 2018

A broad dual-band terahertz metamaterial filter with sharp out-of-band rejections is designed and demonstrated. The center frequencies of the first and the second bands occur at 0.35 THz and 0.96 THz with 3 dB relative bandwidth of 31% and 17%, respectively. Results are measured using a THz time-domain spectroscopy system that shows agreement with simulations. Physical mechanisms of the broad dual-band resonance are clarified based on transmissions of different structures and surface current density distributions. Influence of structure parameters on the transmission characteristics are discussed. Symmetry of the structure ensures the filter polarization independence at normal incidence. These results supported by the design of the filter could find applications in broad multi-band sensors, terahertz communication systems, and other emerging terahertz technologies.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.8B
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• pp.1188-1196
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• 2010

In this paper, worldwide standards and regulations on in-band/out-of-band emission characteristics of DMB broadcasting equipments are reviewed, and emission mask requirements of terrestrial low power DMB repeater under 10mW/MHz are analyzed. Out-of-band emission mask drafts suitable for single/multiple block low power repeaters are proposed. Validity and usefulness of the proposed drafts is evaluated and verified in the several experiments. Using the proposed standard, small-sized and cost-effective DMB repeater can be easily implemented to broaden DMB broadcasting coverage by reducing weak signal areas.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.3
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• pp.45-55
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• 2000

DAB(Digital Audio Broadcasting)는 기존 아날로 그 방식 AM과 FM 라디오 방송의 한계와 문제점을 극복하고 CD 수준 음질의 오디오를 포함한 다양한 멀티미디어 서비스를 제공하는 차세대 라디오 방송이다. DAB는 전송 주파수 대역에 따라 기존의 FM/AM 대역과 다른 새로운 대역을 사용하는 Out-of-Band 방식과 기존의 FM/AM 대역을 사용하는 In-Band 방식으로 분류할 수 있다. Out-of-Band 방식으로는 유럽의 Eureka-147과 일본의 협대역 ISDB-T(Integrated Services Digital Broadcasting-Terrestrial) 방식이 있으며, In-Band 방식은 미국의 USADR(USA Digital Radio)사와 LDR(Lucent Digital Radio)사가 개발하고 있는 IBOC(In-Band On Channel) 방식과 국내 한국전자통신연구원(ETRI)에서 개발 중인 IBAC(In-Band Adjacent Channel) 방식이 있다. 본 고에서는 DAB의 전송 주파수 대역에 따른 방식별 특성을 고찰하고 유럽, 일본, 미국과 국내에서 상용화 서비스 또는 개발되고 있는 DAB 시스템의 기술동향을 분석 한다.

• Progress in Superconductivity
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• v.4 no.2
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• pp.132-136
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• 2003

Extremely selective high temperature superconducting (HTS) band -pass filters were developed for the base transceiver station applications of Digital Cellular communication Service (DCS). The filters have a bandwidth of 25 MHz at a center frequency of 834 MHz. There are 12 resonators which have spiral-meander microstrip-line structures in order to reduce far-field radiations with a reasonable tunability. As a result, the size of filters is 5 mm $\times$ 17 mm $\times$ 41 mm. Device characteristics exhibited a low insertion loss of -0.4 dB with a -0.2 dB ripple and a return loss better than -10 dB in the pass-band at 65 K. The out-of-band signals were attenuated better than 60 dB about 3.5 MHz from the lower band edge, and 3.8 MHz from the higher band edge.

• Journal of IKEEE
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• v.20 no.1
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• pp.54-60
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• 2016

In this paper, out-of-band emission regulations and measurement methods of terrestrial DTV broadcasting services are analyzed, and a novel method to evaluate the out-of-band emission characteristics of DTV transmitter is proposed. Experimental results show that proposed method can be easily used to measure the characteristics of DTV transmitter with inexpensive measuring equipments. With a few modifications, proposed method can be widely adopted to measure the RF performances of the general radio equipments efficiently.