• Proceedings of the Korean Institute of Communication Sciences Conference
• /
• 2004.07a
• /
• pp.88-88
• /
• 2004

• TTA Journal
• /
• s.93
• /
• pp.132-137
• /
• 2004

한국정보통신기술협회(이하 TTA)는 지난 2004년 4월 22일 CDMA휴대폰에 대한 시험인증 기술동향을 소개하고자''제 1회 Global CDMA Handset Testing Technology 세미나''를 개최하였다. 본 행사에서는 현재 Qualcomm의 주도로 추진중인 TRAC 인증프로그램의 개요와 시험기술 및 시험장비 개발 현황 등이 소개되었다. 본 고를 통해 TRAC 인증프로그램을 중심으로 CDMA휴대폰 시험인증기술 동향을 소개하도록 한다.

• Proceedings of the Korea Society of Design Studies Conference
• /
• 2001.10a
• /
• pp.26.1-26
• /
• 2001

• 한국ITS학회:학술대회논문집
• /
• 2002.11a
• /
• pp.198-201
• /
• 2002

• 한국ITS학회:학술대회논문집
• /
• 2004.11a
• /
• pp.97-100
• /
• 2004

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.49 no.5
• /
• pp.91-98
• /
• 2012

Since the major cellular data service providers in U.S, Japan as well as in Korea started the LTE (Long Term Evolution) service, there has been more strong need for the methods that can accurately measure the MIMO (Multi Input-Multi Output) OTA (Over The Air) performance of LTE handsets because the performance of the MIMO antenna determines the data throughput in the downlink. In this paper, the hand effect on the MIMO antenna performance is analyzed by numerically and experimentally. The hand effect on the LTE mobile handset is analyzed by measuring the link level performance in the MIMO OTA system.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.6 no.2
• /
• pp.113-118
• /
• 2007

KPCS internal antenna in this paper, is designed and fabricated using the theory based on the folded monopole antenna. I propose folded monopole internal antenna which has high gain low profile structure with easy installation into the handset of mobile phone. Design frequency is 1.8 GHz that is a center frequency of Korea PCS frequency band, and the impedance variances due to change of antenna structure as a length and width are simulated. Measurements show that input VSWR range under 2:1 is 1.72 - 1.88 GHz, and radiated H-plane pattern is omnidirectional under passive state. Active sensitivities and output power of phone applied antenna are $-105\;{\sim}\;-108\;dBm$ and $22.5\;{\sim}\;23.6\;dBm$ max., respectively.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.17 no.2 s.105
• /
• pp.221-227
• /
• 2006

The SAR evaluation system with 9 stationary probes inserted into the object to be surveyed can calculate area SAR value based on the 9 measured electric field data. The results can be acquired in a few seconds by converting obtained area SAR to the volume SAR. The system can be very useful tool in the stages of handset development for mobile communication as well as in the handset production line because of its rapid SAR measurement ability. The validity of the measurement system is checked by showing that the measured SAR values agree well with reference SAR values suggested in the reference documents.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.20 no.7
• /
• pp.603-607
• /
• 2009

In this paper, a GPS antenna is designed by using metal film which can be attached on the case of battery without additional space for antenna in GPS band operation. The proposed metal film has a half-wavelength slot radiator. The slot radiator is fed by th electromagnetic field coupled from the GSM850/PCS band antenna. The proposed GPS antenna obtains about 20 MHz bandwidth(VSWR<3) which can cover entire GPS band. The antenna has an average gain of -3.8 dBi.

• ETRI Journal
• /
• v.36 no.2
• /
• pp.214-223
• /
• 2014

A fully-integrated penta-band reconfigurable power amplifier (PA) is developed for handset Tx applications. The output structure of the proposed PA is composed of the fixed output matching network, power and frequency reconfigurable networks, and post-PA distribution switches. In this work, a new reconfiguration technique is proposed for a specific band requiring power and frequency reconfiguration simultaneously. The design parameters for the proposed reconfiguration are newly derived and applied to the PA. To reduce the module size, the switches of reconfigurable output networks and post-PA switches are integrated into a single IC using a $0.18{\mu}m$ silicon-on-insulator CMOS process, and a compact size of $5mm{\times}5mm$ is thus achieved. The fabricated W-CDMA PA module shows adjacent channel leakage ratios better than -39 dBc up to the rated linear power and power-added efficiencies of higher than around 38% at the maximum linear output power over all the bands. Efficiency degradation is limited to 2.5% to 3% compared to the single-band reference PA.