• Proceedings of the International Microelectronics And Packaging Society Conference
• /
• 2000.11a
• /
• pp.61-64
• /
• 2000

We fabricated and characterized Low Noise Amplifier (LNA) using MCM-C (Multi-Chip-Module-Cofired) technology for 2.14 GHz IMT-2000 mobile terminal application. First, We designed LNA circuits and simulated it's high frequency characteristics using circuits simulator. For the simulation, we adopted high frequency libraries of all the devices used in LNA samples. By the simulation, Gain was 17 dB and Noise Figure was 1.4 dB. We used multilayer process of LTCC (Low Temperature Co-fired Ceramics) substrate and conductor, resistor pattern for the MCM-C LNA fabrication. We made 2 buried inductors, 2 buried capacitors and 3 buried resistors. The number of the total layers was 6. On the top layer, we patterned microstrip line and pads for the SMT device. We measured the high frequency characteristics, and the results were 14.7 dB Gain and 1.5 dB Noise Figure.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
• /
• v.8 no.2
• /
• pp.90-95
• /
• 2009

All-optical fiber-type gain flattening filer (GFF) for an EDFA (Erbium doped fiber amplifier) were fabricated by using a FBT (fiber biconical tapered) process and the performance of the GFF was tested and athermal package was proposed. Historically, the chief contributor to gain unevenness has been the EDFA. Due to the inherent gain response of the EDFA's operation, there is always a modest imbalance in the gain applied as a function of wavelength. FBT methods have been used to make fiber type couplers and WDM filter since 1980. Attractivity of this methods was simple, cost effective and thermal stability. Simulation program tool is made to design target GFF profile for this paper. Fiber coupler manufacturing machine is modified for the GFF process. The final GFF is obtained by cascading 4 unit filter that has 6 taper stage. Test result shows 1 dB of wavelength flatness in the C band. Polarization dependent loss is under 0.15dB. The center wavelength variation is below ${\pm}$0.35nm at the temperature range of $20^{\circ}C$ to $70^{\circ}C$.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.27 no.5C
• /
• pp.522-529
• /
• 2002

MMIC circuits in whole receiver system was fabricated based on GaAs pHEMT technology. And a V-band downconverter module was fabricated by integrating these circuits. The downconverter module consists of a LO drive power amplifier which generates 24dBm output power, a low noise amplifier(LNA) which shows 20 dB small signal gain, an active parallel feedback oscillator which generates 1.6 dBm output power, and a cascode mixer which shows over 6dB conversion gain. The good conversion gain performance of our mixer made no need to attach any IF amplifier which grows conversion gain. Measured results of the complete downconverter show a conversion gain of over 20 dB between 57.5 GHz and 61.7GHz without IF amplifier.

• The Transactions of the Korean Institute of Electrical Engineers C
• /
• v.53 no.8
• /
• pp.443-446
• /
• 2004

In this paper, a multi-band ceramic chip antenna for WLAN(Wireless LAN) applications is designed. The design target is to obtain 0 dBi of coverage gain with omni directional radiation pattern. The antenna is fabricated using Low Temperature Co-fired Ceramic(LTCC) technology. The size of the chip antenna is $2.2{\times}9.65{\times}1.02$mm. The measured antenna gain is 1 dBi at 2.44 GHz and 0.5 dBi at 5.5 GHz. The omni directional radiation pattern for the two operating bands is obtained. The measured bandwidth(S11=-10 dB) are 90 MHz at 2.44 GHz and 1280 MHz at 5.5 GHz respectively

• Journal of electromagnetic engineering and science
• /
• v.7 no.3
• /
• pp.103-108
• /
• 2007

In this paper, a low-power 2.4 GHz front-end for sensor network application (IEEE 802.15.4 LR-WPAN) is designed in a 0.18 um CMOS process. A power supply circuit with a novel temperature-compensation scheme is presented. The simulation and measurement results show that the front-end (LNA, Mixer) can achieve a voltage gain of 35.3 dB and a noise figure(NF) of 3.1 dB while consuming 5.04 mW (LNA: 2.16 mW, Mixer: 2.88 mW) of power at $27^{\circ}C$. The NF includes the loss of BALUN and BPF. The low-IF architecture is used. The voltage gain, noise figure and third-order intercept point (IIP3) variations over -45$^{\circ}C$ to 85$^{\circ}C$ are less than 0.2 dB, 0.25 dB and 1.5 dB, respectively.

• Journal of the Korean Institute of Telematics and Electronics C
• /
• v.36C no.9
• /
• pp.13-19
• /
• 1999

This paper describes a design of an 8-bit 100KSPS 1mW CMOS A/D Converter. Using a novel systematic offset cancellation technique, we reduce the systematic offset voltage of operational amplifiers. Further, a new Gain amplifier is proposed. The proposed A/D Converter is fabricated with a $0.6{\mu}m$ single-poly triple-metal n-well CMOS technology. INL and DNL is within ${\pm}1LSB$, and SNR is about 43dB at the sampling frequency of 100KHz. The power consumption is $980{\mu}W$ at +3V power supply.

• Journal of the Korean Institute of Telematics and Electronics C
• /
• v.36C no.5
• /
• pp.48-55
• /
• 1999

This paper describes automatic gain control circuit (AGC) design techniques for CMOS CCD camera interface systems. The required gain of the AGC in the proposed system is controlled directly by digital bits without conventional extra D/A converters and the signal settling behavior is almost independent of AGC gain variation at video speeds. A capacitor-segment combination technique to obtain large capacitance values considerably improves the effective bandwidth of the AGC based on switched-capacitor techniques. A proposed layout scheme for capacitor implementation shows AGC matching accuracy better than 0.1 %. The outputs from the AGC are transferred to a 10b A/D converter integrated on the same chip. The proposed AGC is implemented as a sub-block of a CCD camera interface system using a 0.5 um n-well CMOS process. The prototype shows the 32-dB AGC dynamic range in 1/8-dB steps with 173 mW at 3 V and 25 MHz.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.17 no.1 s.104
• /
• pp.24-38
• /
• 2006

In this paper, we investigate the design and fabrication of a conical spiral antenna suitable for satellite TT&C applications. The shape of the spiral is optimized using a commercial electromagnetic software for good gain and axial ratio performances over $2.0{\sim}2.3\;GHz$ frequencies. A coaxial infinite balun feeding the spiral is designed using experimental methods. A method for precision fabrication of the spiral is presented. Measurements of the fabricated antenna show satisfactory performances over $2.0{\sim}2.3\;GHz$ such as a reflection coefficient less than -18 dB, a maximum gain greater than 4 dB, a gain greater than 0 dB over angles ${\pm}75^{\circ}$ from the antenna boresight, an axial ratio less than 5 dB over angles ${\pm}90^{\circ}$ from the antenna boresight, a front-back ratio greater than 15 dB.

• Proceedings of the IEEK Conference
• /
• 1998.10a
• /
• pp.323-326
• /
• 1998

A LNA(Low Nosise Amplifer) module for the Ka-band satellite transponder has been developed, which is composed of developed two MMIC chips and 50$\Omega$ line. This LNA exhibited noise figure less than 3.12dB, linear gain higher than 32dB from 30.085GHz to 30.885GHz frequency range. Temperature test from $20^{\circ}to$ $60^{\circ}C$ of the LNA Module showed very small noise figure and linear gain variation of 0.2 dB and 0.4dB.

• Korean Journal of Optics and Photonics
• /
• v.12 no.3
• /
• pp.200-204
• /
• 2001

The structural design and the measured characteristics of optical signal amplification unit for 640 Gbps (10 Gbps$\times$64 ch.) WDM transmission systems are reported. The unit is composed of two sub gain block units for the amplification of C-band (1530-1560 nm) and L-band (1570-1600 nm), respectively. Programmable microprocessors monitor the states of operation and optimize the optical output conditions. Each sub gain block unit can maintain total optical output power of +21 dBm with gain flatness of < 1 dB and noise figure of <7.2 dB for the input power in the dynamic range from-5 to +1 dBm.+1 dBm.