• The Journal of the Acoustical Society of Korea
• /
• v.38 no.2
• /
• pp.200-206
• /
• 2019

In this paper, the characteristics of receiving voltage sensitivity about acoustic package in towed array sonar is analyzed through the numerical simulation and design of experiments. Simulation results show that the variation of receiving voltage sensitivity is caused by the structural resonance mode shape on baseline acoustic package. The effect of design parameters of the acoustic package are analyzed through the design of experiments to reduce the deviation of receiving voltage sensitivity. A change of hydrophone shield can thickness (t) is the greatest effect on the deviation of receiving voltage sensitivity. As a result of water tank test, the acoustic package derived from the design of experiments has reduced deviation of receiving voltage sensitivity.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.5
• /
• pp.2272-2278
• /
• 2011

It is essential to various evaluate about statistic character of the signal and additional noise for optimization of the optical communication system. We expressed various error probability with the m which was bandwidth and a bit numerical function and carried out performance evaluation of a PIN receiver. This research analyzed the receiving sensitivity of the PIN receiver and verified reception sensitivity through computer simulation in the optical communication system. As a result, the receiving sensitivity for PIN receiver are $9.2{\times}10^4$ photon/bit for given error probability.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 2008.04a
• /
• pp.151-154
• /
• 2008

The advanced technical data collected from home and abroad have properly been analyzed, so that they are useful to improve the photoelectric sensitivity tester. The results of this study have quickly been supplied to the related industry. Our research and development team has verified the response characteristics of the light-emitting and -receiving part of the photoelectric sensitivity tester in order to help the local manufacturer to study, develope and produce their photoelectric detectors.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.30 no.3B
• /
• pp.138-143
• /
• 2005

This paper aims to optimize an access probe algorithm for the CDMA 2000 system. The incremental value of PWR_STEP increases as NUM_STEP as 1dBm±0.2 for access probe of the area with good receiving sensitivity when the mobile station transmits via access channel and does not receive any ACK message. However, for the area with weak receiving sensitivity, according to the algorithm of open-loop power control, the transmitting power amplifier becomes saturated and PWR_STEP incremental value keeps performing access probe to 0dBm±0.2. Therefore interference and battery consumption increases according to the transmission of the mobile station. We have optimized the access probe algorithm according to the receiving sensitivity. We transmit the incremental value of access probe power, with delaying as much RT slot value as indicated by IS-95C standard in case of good receiving sensitivity and with delaying RT+l slot value in case of weak receiving sensitivity. Simulation results showed that the proposed algorithm contributes to decrease of the interference and battery consumption according to the transmitting power of the mobile station and improves the call duration.

• Proceedings of the Korea Contents Association Conference
• /
• 2004.11a
• /
• pp.461-465
• /
• 2004

In this paper, we examined receiving parameters of IMT-2000 receiving system and also analyzed them through simulation based on the minimum specification of DCS and PCS mobile station. As a result of simulation, noise figure which is the parameter of specification of the receiving sensitivity is 7.21dB, 6.03dB, and 7.89dB in case of DCS, PCS and IMT-2000 respectively. Therefore we found the receiving sensitivity of IMT-2000 mobile station lower than that of DCS and PCS.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
• /
• 2003.11a
• /
• pp.550-554
• /
• 2003

In order to detect very short electromagnetic pulses (EMP) with picosecond width, a receiving antenna with a wide bandwidth and good sensitivity over several GHz is needed. In this paper, the receiving characteristics of various thin wire monopole (or dipole) antennas with nonreflecting resistive loading are analyzed for determining the optimum configurations. This study also indicates that it is possible to choose an ideal load impedance for achieving the required fidelity and sensitivity. The analysis is facilitated by introducing the frequency transfer function.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 1997.04a
• /
• pp.493-499
• /
• 1997

In this study, the changes in transmitting and receiving characteristics, especially resonance frequencies, of the underwater acoustic planar array transducer by the transformers used in the analog weighting circuit are investigated. Electrical equivalent circuit analysis shows that an ideal transformer does not change the resonance frequency of the transmitting mode, but the resonance frequency which gives the maximum receiving sensitivity can be designed by adjusting the magnitude of reactance of transformer.

• Journal of the Korea Computer Industry Society
• /
• v.2 no.11
• /
• pp.1477-1482
• /
• 2001

In this paper, we examined receiving parameters of receiver and also analyzed them through simulation based on J-STD-018, which is the minimum specification of PCS mobile station. Receiving system was made a passive double balance mixer which has low gain and high IIP3, and an intermediate frequency amplifier for enhancing the low gain. The result of simulating receiving parameter is as follows: noise figure which is the parameter of specification of the receiving sensitivity is 6.746dB, IIP3 which is the parameter of specification of the intermodulation spurious response attenuation is -11.358dBm.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.44 no.4
• /
• pp.413-422
• /
• 2011

An improved split-beam transducer for a 50 kHz fish-sizing echo sounder was developed. The main objective of this study was to minimize the side lobe level in the beam pattern and the distance between acoustic centers for adjacent transducer quadrants in the geometrical arrangement of array elements while maintaining a given number of transducer elements and beam width. To achieve these goals, a 32-element planar array transducer ($6{\times}6$ array with one element in each corner missing) was designed using the Dolph-Chebyshev shading function to suppress side lobes in the array beam pattern and fabricated by arranging the inter-element spacing to be substantially equal to half the wavelength using the transducer element of 0.4 times the wavelength in diameter. The performance characteristics of this split-beam transducer were evaluated in the experimental water tank of $5m{\times}5m{\times}6m$ (length${\times}$height${\times}$width). In this study, the design goal of the beam width and side lobe level for transmitting a beam pattern was initially set at $21^{\circ}$ and -30 dB, respectively. However, the measured beam width at 3 dB was $21^{\circ}$ in both directions with side lobe levels of -24.7 dB in the horizontal plane and -25.6 dB in the vertical plane. The averaged beam width at -3 dB of the receiving beam patterns for four receiving quadrants was $31.4^{\circ}$. The transmitting voltage response was 161.5 dB (re $1{\mu}Pa$/V at 1 m) at 50.23 kHz with a bandwidth of 2.16 kHz, and the averaged receiving sensitivity for four receiving quadrants was -178.13 dB (re 1 V/${\mu}Pa$) at 49.8 kHz with a bandwidth of 2.64 kHz.

• Journal of Institute of Control, Robotics and Systems
• /
• v.19 no.9
• /
• pp.755-759
• /
• 2013

A broad-band underwater acoustic transducer that uses thickness vibration mode, derived from a disk type piezoelectric ceramic, has been proposed and designed for DVL (Doppler Velocity Log). Three different types of acoustic transducer were evaluated with respect to the transmitting voltage response, receiving voltage sensitivity and bandwidth of the transducer. The effect of the acoustic impedance matching layer and backing layer is discussed. The results demonstrated that three matching layer with lossy backing layer is the best configuration for underwater transducer. The trial underwater acoustic transducer with three matching layer has a frequency bandwidth of 55%, maximum transmitting voltage response of 200 dB and a maximum receiving voltage sensitivity of -187.3 dB.