• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.7A
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• pp.1057-1062
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• 2000

Allow me to introduce the development of an FM transmitter. The transmitter uses millmeter waves at the frequency of 60 GHz, and it can produce as much as 20 mW power with the band width of 1 GHz. The great feature of the FM transmitter is that it has been created by the special technique of utilizing the NRD (non radiative dielectric) waveguide. The advantage of adopting the NRD waveguide is that it can significantly reduce transmission loss. We can construct a small-size NRD guide transmitter in a simple way that has superb transmission performance. The NRD guide transmitter is very useful for CATV transmission or transmission over a wide range. In addition, the transmitter has almost the same band width as optical communication, and the data transmission speed of the transmitter is faster than that of optical communication. A transmitter with these merits would be highly appreciated as a way of ultra-highspeed communication network over short distances.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.28A no.10
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• pp.806-813
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• 1991

In this paper, we suggested the diagnosis of the optical FSK transmitter output characteristics using the Micheloson interferometer. The transmitter is designed by the direct frequency modulation effect of a semoconductor laser diode. The optical FSK transmitter consists of a temperature stabilized semiconductor laser diode and an optimally designed equalizer. It is modulated by 100Mbit/s PRBS Generator to diagonosis of Optical FSK transmitter output characteristics. The Michelson Interferometer is used for the optical frequency discriminator which transforms the output frequency of the transmitter to the amplitude of light. The measurement of the performance of the transmitter to the amplitude of light. The measurement of the performance of the transmitter computer the transmitted data and their eye pattern with the simulation results, the received data and their eye pattern. As the result of experiment, the data transfer rate of the transmitters is 100Mbit/s.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.3
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• pp.384-393
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• 2012

Railroad signaling systems perform controlling the distance and routes between trains. Signaling methods on the wayside are to control passively the train speed by using signal flags which are installed on the wayside. ATS(Automatic Train Stop) device is used as the signaling method on the wayside in Korea. The ATS device is assistance equipment of engineers. Signal information is transmitted by combining mutual inductance between the wayside transmitter and on-board receiver. The wayside transmitter performs changing oscillation frequency according to the signal information. The on-board receiver performs controlling the train by receiving the frequency. Currently, the oscillation frequency on the on-board receiver is 78[kHz] in case of normal state. When the on-board receiver is over the wayside transmitter, the oscillation frequency is changed by capacitors of the wayside transmitter according to signal flags. In case of changing the oscillation frequency, the waveform is modified in the wayside transmitter and on-board receiver. This phenomenon is that other signals or communication frequency are included. In this paper, electric model between the wayside transmitter and on-board receiver is suggested and frequency response in the wayside transmitter and on-board receiver including other signals is estimated by the coupling coefficient. Also, the value of coupling coefficient is proposed to exclude other signals and demonstrated by using Matlab and PSpice program.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.63 no.3
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• pp.206-211
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• 2014

In this Paper, We proposed the HLS(Http Live Streaming) transmitter which is operated easily and cheap in all networks and client environments compared to the exist video live streaming transmitter. We analyzed the HLS protocol and then implemented for making the HLS transmitter cheaper and portable. After designing the HLS transmitter hardware using the RISC processor of Arm11 core, we ported the Linux Operating System and implemented the HLS protocol using the open source FFmpeg and Segmenter. For the performance evaluation of the developed HLS transmitter, we made the testing environment which is including the notebook, iPhone, and aroid Phone. In this testing environment, we analysed the received video data at the client displayer. As a results of the performance evaluation, we could certify that the proposed HLS transmitter has a higher performance than the Apple company's HLS.

• ETRI Journal
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• v.45 no.1
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• pp.150-162
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• 2023

The polar delta-sigma modulator (DSM) transmitter architecture exhibits good coding efficiency and can be used for software-defined radio applications. However, the necessity of high clock speed is one of the major drawbacks of using this transmitter architecture. This study proposes a low-complexity timeinterleaved architecture for the polar DSM transmitter baseband part to reduce the clock speed requirement of the polar DSM transmitter using an upsampling technique. Simulations show that using the proposed four-branch timeinterleaved polar DSM transmitter baseband part, the clock speed requirement of the transmitter is reduced by four times without degrading the signal-tonoise-and-distortion ratio.

• International journal of advanced smart convergence
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• v.10 no.4
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• pp.45-51
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• 2021

Polar transmitter can support multi-band and multi-mode operation. The efficiency of frequency usage can be increased if polar transmitters can transmit multi-carrier signals. In this paper the configuration of polar transmitters is investigated to generate multi-carrier signals. Spectrum and CCDF Simulation results of two-carrier signals generated by the polar transmitter can be used to design of PM and AM path in a polar transmitter.

• The Transactions of the Korean Institute of Power Electronics
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• v.25 no.3
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• pp.181-187
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• 2020

In this study, we propose a spherical flux concentration structure for omnidirectional wireless power transfer. Omnidirectional wireless power transfer technology is a method that can transmit power to a transmitter located in an arbitrary position in a two-dimensional or three-dimensional space. However, to improve the power transfer distance in a wireless power transfer system, the diameter of the coil or the number of windings must increase, thereby increasing the size of the transmitter. The proposed transmitter structure adds a ferrite core inside the transmitter coil so that the magnetic flux generated by the transmitter is directed toward the position of the receiver. As a result, the flux linkage and the mutual inductance increase. By implementing the omnidirectional wireless power transfer system using the proposed structure, the power transfer distance can be improved by 65% compared with the conventional system without increasing the size of the transmitter. Simulation shows that the proposed spherical flux concentration structure increases the mutual inductance of the omnidirectional wireless power transmission system.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.11
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• pp.84-91
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• 2009

A high speed serial link transmitter using multi-level signaling is proposed. To achieve high data rate m high speed serial link, 4-pulse amplitude modulation (PAM) is used. By transmitting 2 bit data in each symbol time, high speed data transmission, two times than binary signaling, is achieved. The transmitter transmits current-mode output instead of voltage-mode output Current-mode output is much faster than voltage-mode output, so higher data transmission is available by increasing switching speed of driver. $2^5-1$ pseudo-random bit sequence (PRBS) generator is contained to perform built-in self test (BIST). The 4-PAM transmitter is designed in Dongbu HiTek $0.18{\mu}m$ CMOS technology and achieves 8 Gb/s, 160 mV of eye height with 1.8 V supply voltage. The transmitter consumes only 98 mW for 8 Gb/s transmission.

• Proceedings of the IEEK Conference
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• 2000.07b
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• pp.914-918
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• 2000

In this paper, a next generation high speed QPSK transmitter is designed based on 1.8${\mu}$m design rule. The designed transmitter supports the MPEG2-TS coded packed data for the DAVIC standard. Transmitter is composed of the convolutional coder, the shortened Reed-Solomon coder, and QPSK modulator. The coded packets are modulated in APSK with an RC filter. Especially, Galois Field multiplier with a standard basis is designed with the pipelined parallel architecture. Also, in the QPSK modulator, the RC filter and mixer are simplified into the ROM table, which can improve the performance of the transmitter. The total number of gates for the implemented baseband transmitter is 26,875.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.43 no.2 s.308
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• pp.28-32
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• 2006

In this paper, NTSC TV Transmitter Modulo will be designed and produced which make possible playing the motion picture not only on TV but also on portable TV. NTSC TV Transmitter Module modulates signals that received Video and Audio signals from a mobile on NTSC TV CH4 mechanism. so it has an advantage of convenience that watching the motion picture of mobile on TV without any other cable through transmitting signals by wireless. But it has some demerits of long size antenna and noise sensitiveness. In the future, if some problems like a size of antenna distortion of signal and noise can be solved through continuous researching about Radio Frequency part, it is possible to play mobile motion pictures on the more media like a camcorder, DVD player and so on.