• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.21 no.6
• /
• pp.670-680
• /
• 2010

A low power single-chip CMOS receiver for 60 GHz mobile application are proposed in this paper. The single-chip receiver consists of a 4-stage current re-use LNA with under 4 dB NF, Cgs compensating resistive mixer with -9.4 dB conversion gain, Ka-band low phase noise VCO with -113 dBc/Hz phase noise at 1 MHz offset from 26.89 GHz, high-suppression frequency doubler with -0.45 dB conversion gain, and 2-stage current re-use drive amplifier. The size of the fabricated receiver using a standard 0.13 ${\mu}m$ CMOS technology is 2.67 mm$\times$0.75 mm including probing pads. An RF bandwidth is 6.2 GHz, from 55 to 61.2 GHz and an LO tuning range is 7.14 GHz, from 48.45 GHz to 55.59 GHz. The If bandwidth is 5.25 GHz(4.75~10 GHz) The conversion gain and input P1 dB are -9.5 dB and -12.5 dBm, respectively, at RF frequency of 59 GHz. The proposed single-chip receiver describes very good noise performances and linearity with very low DC power consumption of only 21.9 mW.

• Journal of the Korean Institute of Telematics and Electronics D
• /
• v.36D no.1
• /
• pp.38-46
• /
• 1999

o.25${\mu}m$ T-shaped gate P-HEMT is fabricated and used for design of X0band three stage monolithic microwave integrated circuit(MMIC) low noise amplifier(LNA). The fabricated P-HEMT exhibits an extrinsis transconductance of 400mS/mm and a drain current of 400mA/mm. The RF and noise characteristics show that the current gain cut off frequency is 65GHz and minimum noise figure(NFmin) of 0.7dB with an associated gain of 14.8dB at 9GHz. In the design of the three stage LNA, we have used the inductive series feedback circuit topology with the short stub. The effects of series feedback to the noise figure, the gain, and the stability have been investigated to find the optimal short stub length. The designed three staage LNA showed a gain of above 33dB, a noise figure of under 1.2dB, and ainput/output return loss of under 15dB and 14dB, respectively. The results show that the fabricated P-HEMT is very suitable for a X-band LNA with high gain.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.19 no.4
• /
• pp.484-491
• /
• 2008

In this paper, we design and fabricate the L-band high speed pulsed HPA using LDMOS FET. And we propose the high voltage and high speed switching circuit for LDMOS FET. The pulsed HPA using LDMOS FET is simpler than using GaAs FET because it has a high gain, high output power and sin81e voltage supply. LDMOS FET is suitable for pulsed HPA using switching method because it has $2{\sim}3$ times higher maximum drain-source voltage(65 V) than operating drain-source voltage($V_{ds}=26{\sim}28\;V$). As results of test, the output peak power is 100 W at 1.2 GHz, the rise/fall time of output RF pulse are 28.1 ns/26.6 ns at 2 us pulse width with 40 kHz PRF, respectively.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.8 no.5
• /
• pp.1120-1128
• /
• 2004

In this paper, we has designed and implemented Up-converter for K-band with high IMD3 performance using balanced power amplifier. It is consisted of PA module and, Local Oscillator module with reject Filter, mixer module and If block, and Up-converter has a local loop path to decide whether it operate or not and has the sensing port to inspect output power level. According to the power budget of designed Up-converter, K-band balanced power amplifier was fabricated by commercial MMIC. Measurement results of up-converter show about 40dB Gain, PldB of 29dBm and OIP3 was 38.25dBm, that is good performance compared to power budgets. We has adjusted gate voltage of MMIC to control more than 30 dB gain. This up-converter was used in transceiver for PTP and PTMP, and applied to digital communication system that use QAM and QPSK modulation.

• Journal of Korea Society of Industrial Information Systems
• /
• v.21 no.1
• /
• pp.43-50
• /
• 2016

In this paper, new automatic LC calibrator is proposed for realizing a passive LC filter with almost constant frequency characteristic regardless of the PVT variations. The SAW-less GPS RX front-end is implemented using a 65nm CMOS process using the proposed LC calibrator. Also, new dual-mode low noise amplifier (LNA) structure is proposed to generate the RF signal required for the LC calibrator. The characteristics of the implemented GPS RX front-end show the voltage gain of about 42.5 dB, noise figure of below 1.35 dB, the blocker input P1dB of -24 dBm in case of the worst blocker signal at 1710 MHz frequency, while it consumes 7 mA current at 1.2 V power supply voltage.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.22 no.6
• /
• pp.149-154
• /
• 2022

Due to high power capabilities and high linearity of GaN devices, GaN Low-Noise Amplifiers (LNAs) without a limiter can be implemented in order to improve noise figure and reduce chip area in radar receivers. In this paper, a GaN LNA is presented for Ka-band radar receivers. The designed LNA was realized in a 150-nm GaN HEMT process and measurement results show that the voltage gain of >23 dB and the noise figure of <6.5 dB including packaging loss in the target frequency range. Under the high-power stress test, measured gain and noise figure of the GaN LNA is degraded after the first stress test, but no more degradation is observed under multiple stress tests. Through post-stress noise and s-parameter measurements, we verified that the GaN LNA is resilient to pulsed input power of ~40 dBm.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.53 no.11
• /
• pp.25-31
• /
• 2016

Parasitic capacitance and resistance of FinFET transistors are the important components that determine the frequency performance of the circuit. Therefore, the researchers in our group developed more accurate parasitic capacitance and resistance for FinFETs than BSIM-CMG. To verify the RF performance, proposed model was applied to design an LNA that has $S_{21}$ more than 10dB and center frequency more than 60GHz using HSPICE. To verify the accuracy of the proposed model, mixed-mode capability of 3D TCAD simulator Sentaurus was used. $S_{21}$ of LNA was chosen as a reference to estimate the error. $S_{21}$ of proposed model showed 87.5% accuracy compared to that of Sentaurus in 10GHz~100GHz frequency range. The $S_{21}$ accuracy of BSIM-CMG model was 56.5%, so by using the proposed model, the accuracy of the circuit simulator improved by 31%. This results validates the accuracy of the proposed model in RF domain and show that the accuracies of the parasitic capacitance and resistance are critical in accurately predicting the LNA performance.

• Journal of IKEEE
• /
• v.2 no.1 s.2
• /
• pp.1-14
• /
• 1998

In this paper, Antenna, LNA, Mixer, VCO, and Modulation/Demodulation in Baseband processor which are the RF main components in Wireless LAN system for ultra high-speed communications network are studied. Antenna bandwidth and selective fading due to multipath can be major obstacles in high speed digital communications. To solve this problem, wide band MSA which has loop-structure magnetic antenna characteristics is designed. Distributed mixer using dual-gate GaAs MESFET can achieve over 10dB LO/RF isolation without hybrid, and minimize circuit size. As linear mixing signal is produced, distortions can be decreased at baseband signals. Conversion gain is achieved by mixing and amplification simultaneously. Mixer is designed to have wide band characteristics using distributed amplifier. In VCO design, Oscillator design method by large signal analysis is used to produce stable signal. Modulation/Demodulation system in baseband processor, DS/SS technique which is robust against noise and interference is used to eliminate the effect of multipath propagation. DQPSK modulation technique with M-sequences for wideband PN spreading signals is adopted because of BER characteristic and high speed digital signal transmission.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.21 no.11
• /
• pp.1275-1284
• /
• 2010

100 MHz bandwidth and 1 Gbit/s data speed are needed in LTE-advanced for the next generation mobile communication system. Therefore, spectrum aggregation method has been studied recently to extend usable frequency bands. Also bandwidth utilization is increased since vacant frequencies are used to communicate. However, transceiver structure requires the digital RF and SDR. Therefore, frequency synthesizer and PA must operate over wide-bandwidth and RF impairments also increases in transceiver. Uplink of LTE advanced uses DFT-S OFDM using plural power amplifier. The effect of ICI increases in frequency domain of receiver due to phase noise and IQ imbalance. In this paper, we analyze influences of ICI in frequency domain of receiver considering phase noise and IQ imbalance in multiband system. Also, we separate phase noise and IQ imbalance effect from channel response in frequency domain of uplink system. And we propose a method to estimate the channel exactly and to compensate IQ imbalance and phase noise. Simulation result shows that the proposed method achieves the 2 dB performance gain of BER=$10^{-4}$.

• Korean Journal of Remote Sensing
• /
• v.23 no.2
• /
• pp.137-144
• /
• 2007

In KORDI (Korea Ocean Research and Development Institute), the KOSC (Korea Ocean Satellite Center) construction project is being prepared for acquisition, processing and distribution of sensor data via L-band from GOCI (Geostationary Ocean Color Imager) instrument which is loaded on COMS (Communication, Ocean and Meteorological Satellite); it will be launched in 2008. Ansan (the headquarter of KORDI) has been selected for the location of KOSC between 5 proposed sites, because it has the best condition to receive radio wave. The data acquisition system is classified into antenna and RF. Antenna is designed to be $\phi$ 9m cassegrain antenna which has 19.35 G/T$(dB/^{\circ}K)$ at 1.67GHz. RF module is divided into LNA (low noise amplifier) and down converter, those are designed to send only horizontal polarization to modem. The existing building is re-designed and arranged for the KOSC operation concept; computing room, board of electricity, data processing room, operation room. Hardware and network facilities have been designed to adapt for efficiency of each functions. The distribution system which is one of the most important systems will be constructed mainly on the internet. and it is also being considered constructing outer data distribution system as a web hosting service for offering received data to user less than an hour.