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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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The Journal of Korean Institute of Electromagnetic Engineering and Science
Journal Basic Information
Journal DOI :
The Korean Institute of Electromagnetic Engineering and Science
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Volume & Issues
Volume 23, Issue 12 - Dec 2012
Volume 23, Issue 11 - Nov 2012
Volume 23, Issue 10 - Oct 2012
Volume 23, Issue 9 - Sep 2012
Volume 23, Issue 8 - Aug 2012
Volume 23, Issue 7 - Jul 2012
Volume 23, Issue 6 - Jun 2012
Volume 23, Issue 5 - May 2012
Volume 23, Issue 4 - Apr 2012
Volume 23, Issue 3 - Mar 2012
Volume 23, Issue 2 - Feb 2012
Volume 23, Issue 1 - Jan 2012
Selecting the target year
A CPW-Fed Ultra-Wideband Planar Monopole Antenna for UHF Band Applications
Yoo, Tae-Hoon ; Kim, Tae-Hyung ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 23, issue 7, 2012, Pages 761~767
DOI : 10.5515/KJKIEES.2012.23.7.761
In this paper, a novel ultra-wideband planar monopole antenna for the UHF communications and Digital-TV reception is proposed. The proposed antenna fed by a coplanar waveguide(CPW) is based on a triangular patch that has a broadband characteristic. To further increase the bandwidth of the triangular patch antenna, the top side of the regular triangular patch is loaded with a notch cut and each oblique side with a step. In addition, a slope is given to the ground plane of the CPW structure. Experimental results show that the -10 dB return loss bandwidth of the proposed antenna is 2,320 MHz from 480~2,800 MHz(5.83:1 bandwidth), which covers all the frequency bands of the various wireless communication systems and Digital TV broadcasting in the UHF band. Within the entire operating frequency range, the measured antenna gain in y-z plane(E-plane) varies from 3.01 to 4.71 dBi.
A Branch-Line Hybrid Using Triangle-Patch Type Artificial Transmission Line
Oh, Song-Yi ; Hwang, Hee-Yong ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 23, issue 7, 2012, Pages 768~773
DOI : 10.5515/KJKIEES.2012.23.7.768
A branch-line hybrid using microstrip artificial transmission lines(ATLs) with slotted-triangular patches is proposed. The proposed artificial transmission line is compact in structure as well as easy to adjust the characteristic impedance and electrical length of equivalent transmission line by changing the slot's parameters; hence, it is useful for miniaturizing conventional transmission lines. The designed branch-line hybrid, because of the use of the right angled isosceles triangular shaped artificial transmission lines as building blocks, has no useless empty space, and hence optimally miniaturized. A fabricated 3 dB branch-line hybrid shows the coupling variation of
dB and the phase difference between two output ports of
within 15 % bandwidth at 2.45 GHz center frequency. The size of proposed branch-line hybrid is only 38% of the conventional branch-line hybrid.
Periodically Corrugated Transmission Line Design for Crosstalk Reduction
Oh, Jang-Teak ; Park, Ik-Mo ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 23, issue 7, 2012, Pages 774~783
DOI : 10.5515/KJKIEES.2012.23.7.774
In this paper, a periodically corrugated transmission line is proposed. The proposed transmission line can reduce crosstalk between transmission lines. The corrugated transmission line can adjust the amount of inductive coupling and capacitive coupling equally. Thus, the crosstalk is effectively reduced because the inductive coupling and capacitive coupling cancel each other. The corrugated transmission line is fabricated on RO4003 substrate with a dielectric constant of 3.38 and a thickness of 0.508 mm. The simulated far-end crosstalks of conventional transmission line and corrugated transmission line with a period of A=1 mm have maximum values of -3.6 dB and -22 dB, respectively, up to 30 GHz. Measurement results showed that far-end crosstalks of the conventional and corrugated transmission line have maximum values of -6.3 dB and -20.5 dB, respectively, up to 30 GHz.
Digital Low-Power High-Band UWB Pulse Generator in 130 nm CMOS Process
Jung, Chang-Uk ; Yoo, Hyun-Jin ; Eo, Yun-Seong ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 23, issue 7, 2012, Pages 784~790
DOI : 10.5515/KJKIEES.2012.23.7.784
In this paper, an all-digital CMOS ultra-wideband(UWB) pulse generator for high band(6~10 GHz) frequency range is presented. The pulse generator is designed and implemented with extremely low power and low complexity. It is designed to meet the FCC spectral mask requirement by using Gaussian pulse shaping circuit and control the center frequency by using CMOS delay line with shunt capacitor. Measurement results show that the center frequency can be controlled from 4.5 GHz to 7.5 GHz and pulse width is 1.5 ns and pulse amplitude is 310 mV peak to peak at 10 MHz pulse repetition frequency(PRF). The circuit is implemented in 0.13 um CMOS process with a core area of only
and dissipates the average power of 11.4 mW at an output buffer with 1.5-V supply voltage. However, the core consumes only 0.26 mW except for output buffer.
Pulse 2 kW RF Limiter at S-band
Jeong, Myung-Deuk ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 23, issue 7, 2012, Pages 791~796
DOI : 10.5515/KJKIEES.2012.23.7.791
A RF limiter is a component to protect the receiver front end from undesired signal. A RF limiter is a key component whose output is constant level for all inputs above a critical value. A RF limiter use a diode to pass signals of low power while attenuating those above some threshold. A RF limiter for receiver protection in modern radar systems is playing a vital role in order to meet challenges of new interference threats and complicated electromagnetic environments. This paper proposed a new circuit for high power RF limiter whose structure is the combination of the PIN diode and Limit diode. PIN diode take a use of its isolation characteristics which act as a switch does. A 2 kW RF limiter with 200 us pulse width at S-band was developed. It shows good agreements between estimated value and measured results.
Design of QAPM Modulation for Low Power Short Range Communication and Application of Compressive Sensing
Kim, So-Ra ; Ryu, Heung-Gyoon ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 23, issue 7, 2012, Pages 797~804
DOI : 10.5515/KJKIEES.2012.23.7.797
In this paper, we propose a QAPM(Quadrature Amplitude Position Modulation) modulation using compressive sensing for the purpose of power efficiency improvement. QAPM modulation is a combination technique of QAM (quadrature amplitude modulation) and PPM(Pulse Position Modulation). Therefore it can decrease the transmission power and improve BER performance. Moreover, even if the band width is widened when the number of positions is increased, high sparsity characteristic caused by position number can be applied to compressive sensing technique. Compressive sensing has recently studied as a method that can be successfully reconstructed from the small number of measurements for sparse signal. Therefore, the proposed system can lower price of receiver by reducing sampling rate and has performance improved by using QAPM modulation. And the results are confirmed through simulations.
Analysis of Reference Signal for Immunity Test of Sound System and Television Broadcast Receiver
Choi, Su-Na ; Cho, Sung-Woong ; Park, Seung-Keun ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 23, issue 7, 2012, Pages 805~814
DOI : 10.5515/KJKIEES.2012.23.7.805
Intermittent or periodic signals with undulating amplitudes of mobile devices cause interference noise at audible frequency to the sound system which is installed nearby. In this regard, it is recently issued that the intermittently transmissions of LTE mobile phones cause the interference noises with sound systems, similar to that of GSM mobile phones. For retaining the immunity to noises, a national regulation KN20 suggests a 1 kHz AM 80 % and a CDMA modulation signal as reference signals for immunity test of sound and television broadcast receiver. In this paper, the effects of interference noises of AM and CDMA are compared with those of GSM and LTE, and the improvement of reference signal for national immunity test of sound systems is suggested. It is recommended to delete the CDMA modulation signal from reference signals for immunity test because it hardly cause interference noise with sound systems. On the other hand, it is desirable to select the modulation signal of LTE instead of CDMA as a reference signal for immunity test of sound system and television broadcast receiver because many people use the LTE service and it is analysed that the LTE signal causes considerable interference noises.
The Relation of Time Resolution and Radial Velocity Accuracy of a CW Doppler Radar
Ryu, Chung-Ho ; Jang, Yong-Sik ; Choi, Ik-Hwan ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 23, issue 7, 2012, Pages 815~821
DOI : 10.5515/KJKIEES.2012.23.7.815
A CW Doppler radar can measure radial velocity of an object. It detects a Doppler frequency shift that is proportioned to radial velocity of a moving object. To detect a Doppler frequency shift, FFT(Fast Fourier Transform) is conducted. In this process, the time domain received signal is transformed to a frequency domain. A number of FFT affects not only the time resolution but also signal to noise ratio of received signal. So finally it is related with a radial velocity accuracy. Therefore in this paper, it is described the relation of time resolution and the radial velocity accuracy.
Approximated Modeling Technique of Weibull Distributed Radar Clutter
Nam, Chang-Ho ; Ra, Sung-Woong ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 23, issue 7, 2012, Pages 822~830
DOI : 10.5515/KJKIEES.2012.23.7.822
Clutters are all unwanted radar returns to affect on detection of targets. Radar clutter is characterized by amplitude distributions, spectrum, etc. Clutter is modelled with considering these kinds of characteristics. In this paper, a Weibull distribution function approximated by uniform distribution function is suggested. Weibull distribution function is used to model the various clutters. This paper shows that the data generated by the approximated solution of Weibull distribution function satisfy the Weibull probability density function. This paper shows that the data generation time of approximated Weibull distribution function solution is reduced by 20 % compared with the generation time of original Weibull probability density function.
Development of Exponential Model of Korea for Improved Altitude Estimation Performance of High-Altitude Target at Radar System
Moon, Hyun-Wook ; Jeon, Min-Hyun ; Kim, Woo-Joong ; Oh, Seong-Keun ; Lee, Jong-Hyun ; Kwon, Se-Woong ; Yoon, Young-Joong ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 23, issue 7, 2012, Pages 831~839
DOI : 10.5515/KJKIEES.2012.23.7.831
In this paper, an exponential model of Korea is proposed to minimize an altitude-error of high-altitude target due to atmosphere refraction at radar system. The relation between surface refractivity and refractivity gradient, which is extracted using the least square fit from the measured data at 7 weather stations, is applied to the exponential model. And in order to verify the proposed model, the altitude-errors for a standard atmosphere, a CRPL(Central Radio Propagation Lab.) exponential model, the proposed model are extracted and analyzed using a ray tracing. As a result, the proposed model can improve the altitude estimation performance of radar compared to conventional atmosphere refractive index models.
Dual-Band Metamaterial Absorber without Metallic Back-Plate
Lee, Hong-Min ; Lee, Hyung-Sup ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 23, issue 7, 2012, Pages 840~843
DOI : 10.5515/KJKIEES.2012.23.7.840
In this paper, the authors present a new design for a dual-band metamaterial(MTM) absorber that utilizes resonant-magnetic inclusion of a split-ring resonator(SRR). The proposed MTM unit cell is constructed by two open complementary split-ring resonators(OCSRRs) and an SRR arrangement. To avoid the need for metallic back plate a planar array of SRRs for resonant-magnetic inclusion is placed facing toward the incident wave propagation direction. Each unit cell is printed on the two sides of a FR-4 substrate. A prototype absorber was fabricated with a planar array of
unit cells, and measured. The proposed backplane-less absorber can be used for microwave applications.
Compact and Broadband 90° Coupler Using a Metamaterial
Kim, Hong-Joon ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 23, issue 7, 2012, Pages 844~847
DOI : 10.5515/KJKIEES.2012.23.7.844
By using LHTL(Left-Handed Transmission Line) which is a form of a metamaterial and conventional RHTL (Right-Handed Transmission Line), we designed, fabricated and tested a broadband
coupler which is a basic circuit for I-Q vector signal generation. Synthetic LHTL and RHTL were implemented with capacitors and inductors only, that the size is minimized. Also, by implementing a Wilkinson power divider which is required for the suggested circuit using a synthetic RHTL, the size of whole circuit is only
. For the frequency range 0.8~1.25 GHz, the phase difference at the outputs maintained
and thus, a broadband
coupler could be made in a compact form. for the same frequency range, the insertion loss is less than 1.6 dB and return loss is more than 10.1 dB. To the best of our knowledge, this is the smallest and broadband
coupler for the frequency range and if the circuit is made with MMIC(Monolithic Microwave Integrated Circuit) technology, the size will be reduced much further.
Effective Detection and Suppression of Low-Amplitude Interference in FMCW Radars
Cho, Byung-Lae ; Lee, Jung-Soo ; Lee, Jong-Min ; Sun, Sun-Gu ;
The Journal of Korean Institute of Electromagnetic Engineering and Science, volume 23, issue 7, 2012, Pages 848~851
DOI : 10.5515/KJKIEES.2012.23.7.848
As many radar systems are simultaneously operated with overlapping frequency bands, interference between systems inevitably occurs. Because interference can degrade radar performance, suppression of interference is a critical issue in radar systems. In this letter, a new interference detection and suppression method using a short-time Fourier transform and an adaptive notch filter is proposed. An experiment is carried out to validate the proposed method and the results demonstrate that the proposed method is suitable for application in real FMCW radars.