• Title/Summary/Keyword: 2$\times$2 array

Search Result 742, Processing Time 0.036 seconds

A $2{\times}2$ Microstrip Patch Antenna Array for Moisture Content Measurement of Paddy Rice (산물벼 함수율 측정을 위한 $2{\times}2$ 마이크로스트립 패치 안테나 개발)

  • 김기복;김종헌;노상하
    • Journal of Biosystems Engineering
    • /
    • v.25 no.2
    • /
    • pp.97-106
    • /
    • 2000
  • To develop the grain moisture meter using microwave free space transmission technique, a 10.5GHz microwave signal with the power of 11mW generated by an oscillar with a dielectric resonator is transmitted to an isolator and radiated from a transmitting $2{\times}2$ microstrip patch array antenna into the sample holder filled with the 12 to 26%w.b. of Korean Hwawung paddy rice. the microwave signal, attenuated through the grain with moisture, is collected by a receiving $2{\times}2$ microstrip patch array antenna and detected using a Shottky diode with excellent high frequency characteristic. A pair of light and simple microstrip patch array antenna for measurement of grain moisture content is designed and implemented on atenflon substrate with trleative dielectric constant of 2.6 and thickness of 0.54 by using Ensemble ver. 4.02 software. The aperture of microstrip patch arrays is 41 mm width and 24mm high. The characteristics of microstrip patch antenna such as grain. return loss, and bandwidth are 11.35dBi, -38dB and 0.35GHz($50^{\circ}$ at far-field pattern of E and H plane. The width of the sample holder is large enough to cover the signal between the antennas temperature and bulk density respectively. The calibration model for measurement of grain moisture content is proposed to reduce the effects of fluectuations in bulk density and temperature which give serious errors for the measurements . From the results of regression analysis using the statistically analysis method, the moisture content of grain samples (MC(%)) is expressed in terms of the output voltage(v), temperature (t), and bulk density of samples(${\rho}b$)as follows ;$$MC(%)\;=\;(-3.9838{\times}10^{-8}{\times}v^{3}+8.023{\times}10^{-6}{\times}v^{2}-0.0011{\times}v-0.0004{\times}t+0.1706){\frac{1}{{\rho}b}}{\times}100$ Its determination coefficient, standard error of prediction(SEP) and bias were found to be 0.9855, 0.479%w.b. and -0.0.369 %w.b. respectively between measured and predicted moisture contents of the grain samples.

  • PDF

SIW-Based 2×4 Array Antenna with a Sequential Feeding for X-Band Satellite Communication (순차적 급전을 이용한 위성 통신용 SIW 2×4 배열 안테나)

  • Jung, Eun-Young;Lee, Jae-Wook;Lee, Taek-Kyung;Lee, Woo-Kyung
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.22 no.2
    • /
    • pp.125-130
    • /
    • 2011
  • In this paper, SIW-based $2{\times}4$ uniform array antenna with a sequentially fed 8-way power divider with an equal division characteristic is proposed for an application of X-band satellite communication. In particular, sequential feeding structures with a progressive phase difference of 90 degrees between the nearest elements have been suggested to protect the cancellation of electric fields due to the array alignments and to enhance the purity of RHCP(Right-Handed Circular Polarization). The obtained results according to the return loss bandwidth, RHCP antenna gain, axial ratio bandwidth are 760 MHz ranging from 7.90 to 8.66 GHz under the criterion of less than -10 dB, 14.3 dBic at 8.3 GHz, and 600 MHz from 8.15 to 8.75 GHz, respectively. In addition, it is observed that the equal-division characteristic of SIW-based 8-way power divider is approximately -9.2 dB in all ports.

Design of a 1 × 2 Array Microstrip Antenna for Active Beam Compensation at X-band (X-밴드 능동적 빔 보상 1 × 2 배열 마이크로스트립 안테나 설계)

  • Choi, Yoon-Seon;Woo, Jong-Myung
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.15 no.2
    • /
    • pp.111-118
    • /
    • 2016
  • This paper presents an X-band (9.375 GHz) $1{\times}2$ array microstrip antenna which is capable of active beam compensation for installation of an unmanned aerial vehicle (UAV). First of all, a basic $1{\times}2$ array microstrip antenna incorporated with wilkinson power divider was designed and performance of the array antenna was verified. Next, to verify beam steering performance of the designed array microstrip antenna, we fabricated a phase shifter, and the wilkinson power divider as module structure and measured characteristics of beam steering according to phase shifting. The main lobe is 0.6 dBi at $0^{\circ}$, and the side lobe decreased 18.8 dB. The reliable radiation pattern was achieved. Finally, an active beam steering microstrip array antenna attached with the phase shifter and the power divider on the back side of the antenna was designed and fabricated to install wing of UAV for compactness. The maximum gain is 0.1 dBi. Therefore, we obtained a basic antenna technology for compensating beam error according to wing deformation of an UAV installed array antennas.

Development of SiPM-based Small-animal PET

  • Lee, Jin Hyung;Lee, Seung-Jae;Chung, Yong Hyun
    • IEIE Transactions on Smart Processing and Computing
    • /
    • v.4 no.5
    • /
    • pp.324-329
    • /
    • 2015
  • A decreased number of readout method is investigated to provide precise pixel information for small-animal positron emission tomography (PET). Small-animal PET consists of eight modules, and each module is composed of a $6{\times}6$ array of $2{\times}2{\times}20mm^3$ lutetium yttrium orthosilicate (LYSO) crystals optically coupled to a $4{\times}4$ array of $3{\times}3mm^2$ silicon photomultipliers (SiPMs). The number of readout channels is reduced by one-quarter that of the conventional method by applying a simplified row and column matrix algorithm. The performance of the PET system and detector module was evaluated with Geant4 Application for Emission Tomography (GATE) 6.1 and DETECT2000 simulations. In the results, all pixels of the $6{\times}6$ LYSO array were decoded well, and the spatial resolution and sensitivity, respectively, of the PET system were 1.75 mm and 4.6% (@ center of field of view, energy window: 350-650 keV).

Design of a Circular Polarization Microstrip $12\times12$ Series-Parallel Array Antenna at 10 GHz (원형 편파 마이크로스트립 $12\times12$ 직-병렬 배열 안테나 설계)

  • 이영주;정명숙;박위상
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.11 no.1
    • /
    • pp.26-36
    • /
    • 2000
  • A circularly polarized $12\times12$ array with application in the satellite communications is designed at 10 GHz. The radiator is an aperture-coupled ring patch, which is suitable of large arrays. The element spacing of the array is chosen to be $0.7\lambda_0$to maintain the main beam in the broadside direction. The array is a sequential array constructed on a series-parallel feed network to obtain high gain and low axial ratio. Measurement results for the array, acquired by experiments in the compact range of POSTECH, showed a directivity of 27.88 dB, a high gain of 25.55 dB, an efficiency of 60%, an axial ratio of 1.74 dB, and a side-lobe level of -13 dB. The bandwidth of the array was 43% when the VSWR was 2, and the bandwidth of the axial ratio was 16%.

  • PDF

Investigation of the Lateral Acoustic Signal Detection Using by Two Fabry-Perot Fiber Optic Sensor Array (두 개의 Fabry-Perot 광섬유 센서 배열을 이용한 횡방향 음압 감지 특성 연구)

  • Lee, Jong kil
    • 대한공업교육학회지
    • /
    • v.31 no.1
    • /
    • pp.185-199
    • /
    • 2006
  • In this paper, to detect lateral direction sound pressure fiber optic sensor using Fabry-Perot interferometeric sensor array was fabricated and experimented. This parallel sensor array composed of one light source and the light split into each sensor using directional coupler and to see the output signal the array system do not need any digital signal processor. As a lateral direction sound source arbitrary sound frequency of 100Hz, 200Hz, and 655Hz using by nondirectional speaker were applied to the array sensor which installed on $60cm{\times}60cm{\times}60cm$ latticed structure. The detected signals from the two sensors were analyzed in the time and frequency domains. It was confirmed that the suggested sensor array detected applied sound source well but there were a little amplitude differences in between the sensors. Because the sensor supported simply at both ends theoretical analysis was performed and its solution was suggested. To compare the theoretical and experimental results arbitrary sound frequency of 2kHz was applied to the sensor array. It shows that experimental results was good agreement with theoretical results.

Expansion of Variable Range of Oscillation Frequency of Active Phased Array Antenna by a Varactor Diode (바랙터다이오드에 의한 능동 위상차 배열 안테나의 발진 주파수 가변 범위의 확장)

  • 최영규
    • The Transactions of the Korean Institute of Electrical Engineers C
    • /
    • v.52 no.11
    • /
    • pp.521-528
    • /
    • 2003
  • A varactor diode was utilized in order to expand variable range of the natural oscillation frequency of an active phased-array antenna. We have conformed experimentally that the variable range of the natural oscillation frequency was expanded about three times in the oscillator controlled by the varactor diode. When frequency difference was given to the oscillators in the two elements antenna system, phase difference was appeared between the oscillators. The 2-, 3-, 5-elements patch antenna array was composed for the beam scanning experiments. All the above patch antennas showed good phased array characteristics. The experimental results are as follows that the scanning angle of the 2-elements array antenna is 28.6$^{\circ}$, the 3-elements array antenna is 29.4$^{\circ}$, and the 5-elements array antenna is 26.2$^{\circ}$.

Design of a Ka-Band Microstrip Array Antenna for Satellite Communication (위성통신용 Ka-Band 마이크로스트립 배열안테나의 설계)

  • 류정기;임인성;이덕재;민경일;오승엽
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.10 no.1
    • /
    • pp.142-149
    • /
    • 1999
  • In this paper, Aperture-coupled microstrip array antenna was designed and manufactured for satellite communication at Ka-Band. We analyzed a microstrip radiation element and designed power divider using $\lambda$g/4 transformer and T-junction power divider. A manufactured Aperture-coupled $2\times2$ microstrip array antenna has a resonant frequency of 20 GHz. The experimental results are as followings : resonant frequency of 19.62 GHz, VSWR 1.0692, return loss -29.61 dB, Bandwidth 1.76 GHz and -3 dB beamwidth $42^{\circ}$.

  • PDF

A Study On The Microstrip Slot Array Antenna Design (마이크로스트립 슬롯 배열 안테나 설계에 관한 연구)

  • 한석진;박익모;신철재
    • Proceedings of the IEEK Conference
    • /
    • 1999.11a
    • /
    • pp.147-150
    • /
    • 1999
  • A T-shaped microstripline-fed printed slot array antenna having wide bandwidth, high gain, and narrow bandwidth is presented in this paper. The proposed antenna is analyzed by using the transmission line model method. We fabricated 4$\times$1 microstrip slot array antenna and measured its return loss and radiation pattern. The maximum bandwidth of this array antenna is from 1.43 ㎓ to 2.60 ㎓, which is 58.1% for the VSWR $\leq$ 2.

  • PDF

A Broadband Microstrip Array Antenna for 3G Smart Antenna System Testbed

  • Rashid, Zainol Abidin Abdul;Islam, Mohammad Tariqul;Jiunn, Ng Kok
    • Journal of The Institute of Information and Telecommunication Facilities Engineering
    • /
    • v.7 no.1
    • /
    • pp.41-58
    • /
    • 2007
  • A compact and broadband $4{\times}1$ array antenna was developed for 3G smart antenna system testbed. The $4{\times}1$ uniform linear array antenna was designed to operate at 1.885 to 2.2GHz with a total bandwidth of 315MHz. The array elements were based on the novel broadband L-probe fed inverted hybrid E-H (LIEH) shaped microstrip patch, which offers 22% size reduction to the conventional rectangular microstrip patch antenna. For steering the antenna beam, a commercial variable attenuator (KAT1D04SA002), a variable phase shifter (KPH350SC00) with four units each, and the corporate 4-ways Wilkinson power divider which was fabricated in-house were integrated to form the beamforming feed network. The developed antenna has an impedance bandwidth of 17.32% ($VSWR{\leq}1.5$), 21.78% ($VSWR{\leq}2$) with respect to center frequency 2.02GHz and with an achievable gain of 11.9dBi. The design antenna offer a broadband, compact and mobile solution for a 3G smart antenna testbed to fully characterized the IMT-2000 radio specifications and system performances.

  • PDF