• Journal of rehabilitation welfare engineering & assistive technology
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• v.4 no.1
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• pp.35-41
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• 2010

By the development of medical devices, high-frequency medical devices are becoming widely used. Imaging diagnosis in hospital and clean treatment by high-frequency medical devices and cancer treatment through high-frequency heaters around us, all serve as the examples. However, it still lacks the measures to the problems of the RF(Radio Frequency) mutual interference between the high-frequency devices. In order to prevent the problematic factors for technical and industrial development, a new reasonable and suitable test method is required. In this paper, we study a standard test method for EMC evaluation to solve the RF mutual interference.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.10 no.6
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• pp.512-521
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• 2017

Telemetry ground station use very high gain directional antenna systems that are sensitive to interference from other RF communication systems, Without appropriate interference protection, these systems could be severely impacted or even rendered useless for mission support. In ECC, we suggested ans interference analysis method between LTE-TDD system and telemetry ground station using 2.3GHz. In this paper, based on the interference analysis scenario considered in Electronic Communication Committee, We have derived mutual coexistence separation distance between telemetry ground station and LTE-TDD system(Base station, User equipment) in Spatial domain.

• Journal of the Korean Physical Society
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• v.80
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• pp.640-646
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• 2022

Hybrid PET/MRI is a useful imaging system that can improve diagnostic accuracy by providing both functional and anatomical information. However, the combination of PET and MRI can lead to mutual interference, which can degrade the performances of both imaging systems. One of the methods that is capable of preserving the performance of both modalities is to apply RF shielding to PET detectors and electronics. The purpose of this study was to propose a new RF shielding method using Au-plated conductive fabric (PCF) tape that could not only minimize RF interference and eddy current, but that could also be applied to complex PET gantry and detector module structures more easily than thin Cu foils, which have been widely used as a shielding material for hybrid PET/MRI systems. To evaluate the performance of the proposed new RF shielding method, the effects of the two RF shield materials (Cu and Au) on the B1 + field generated by the RF head coil were estimated using a computer simulation method. The effects of the Au PCF tape and Cu foil on the homogeneity and SNR of the MR image were also experimentally evaluated using a commercial 3-T MRI. The uniformity of the B1 + field map was slightly decreased by the use of Cu and Au RF shields. The deterioration in the MR image quality caused by the Au PCF tape was less than that caused by Cu foil. The simulation and experimental results indicate that Au PCF tape can serve as an alternative shielding material that reduces RF interference and eddy current for hybrid PET/MRI systems.

• ETRI Journal
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• v.26 no.6
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• pp.605-614
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• 2004

In this paper, we investigate array calibration algorithms to derive a further improved version for correcting antenna array errors and RF transceiver errors in CDMA smart antenna systems. The structure of a multi-channel RF transceiver with a digital calibration apparatus and its calibration techniques are presented, where we propose a new RF receiver calibration scheme to minimize interference of the calibration signal on the user signals. The calibration signal is injected into a multi-channel receiver through a calibration signal injector whose array response vector is controlled in order to have a low correlation with the antenna response vector of the receive signals. We suggest a model-based antenna array calibration to remove the antenna array errors including mutual coupling errors or to predict the element patterns from the array manifold measured at a small number of angles. Computer simulations and experiment results are shown to verify the calibration algorithms.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.11
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• pp.978-984
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• 2015

In this paper, we designed a RF transceiver operating up to 200 km operating range and 45 Mbps data rate. The RF transceiver operates in Ku band and composed of up/down converter, high power amplifier, front-end elements. To satisfy the operating range of RF transceiver, 10W power amplifier was required and realized by using GaN power amplifier. Moreover, to mitigate mutual interference for different bandwidth signals due to the adaptive transmission speed control function, SAW filter bank structure was used. To verify system requirement satisfaction AWR simulation tool was used.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.7
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• pp.500-507
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• 2018

A three-channel radio frequency (RF) monopulse receiver using a data signal with a maximum transmission rate of 274 Mbps was designed. A monopulse receiver using a broadband communication signal was designed to operate in the Ku band, and it consists of a down-conversion module and a signal-processing module. To satisfy the performance of the proposed RF monopulse receiver, a signal-processing function less than the reception sensitivity for each transmission rate according to the adaptive transmission rate is required. To minimize signal reception and mutual frequency interference of various bandwidths, two RF filters were applied. To verify the satisfaction of system requirements, an AWR Corp. simulation tool was used.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.2
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• pp.79-85
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• 2023

To make normal operation of S-Band PSR(Primary Surveillance Radar) which are in operation near distance, Minimizing the mutual frequency interference was studied in this paper. First, the phenomenon of radar receiver was analyzed when the interference between PSR was occurred. And next, the proper S-Band Bandpass filter(BPF) was chosen to deal with the interference. And inhibition performance of BPF was verified by comparative analysis of Radar's RF reception characteristic before and after of BPF application. There is 6.4~7.7 dB passband attenuation when BPF was applied at Radar receiver. So the PSR probability of detection were compared and analyzed to check the radar detection performance was deteriorated or not, And this result proved the usefulness of this study.