Choul-Young Kim

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A 16-element phased array receiver with built-in-self test (BIST) is demonstrated at 76-84 GHz. The BIST technique employs a miniature capacitive coupler located at the input port of each phased-array channel, and uses the receiver I/Q down-converter to measure the amplitude and phase of each channel. This allows for measuring the response of individual(More)
We present a synchronization method and coherent ultra-wideband transceivers for a widely separated multiple-input multiple-output (MIMO) radar. Synchronization is essential for MIMO operation, but a spatially spread radar array is not a good structure for it. A wireless cooperative synchronization method is based on coherency of pulse signals and highly(More)
A quadrature radar topology with a Tx leakage canceller is presented. The canceller is composed of four branch-line hybrid couplers, a 90deg delay line, and a Wilkinson combiner. It has high Tx-to-Rx isolation and wide bandwidth characteristics. The isolation is 35.27 dB at 24 GHz and does not drop below 30 dB over a 2-GHz bandwidth. Given that the(More)
This paper presents a 16-element Q-band transmit/ receive phased array with high receive linearity and low power consumption. The design is based on the all-RF architecture with passive phase shifters and a 1:16 Wilkinson network. An input P<sub>1dB</sub> from -9 to -10 dBm and a noise figure of 10-11.5 dB at 44-46 GHz is achieved in the receive mode with a(More)
A fully integrated 24-GHz CMOS ultra-wideband (UWB) radar transmitter for short-range automotive application is presented. For high-range resolution and improved signal-to-noise ratio, a pulse compression technique using binary phase code is adopted. Design issues of UWB radar transmitter are investigated based on fundamental pulse theory. A pulse former,(More)
This paper presents a K-band CMOS UWB radar transmitter with highly accurate variable delay circuits and a bi-phase modulating pulsed oscillator. The UWB radar transmitter is composed of three blocks: variable delay circuits that consist of a digital synchronized counter and a Vernier delay line (VDL), a baseband control signal generator, and a pulsed(More)
This paper presents a low power UWB radar transceiver IC, which is used to make a radar system with precise range accuracy. The range accuracy is allowed by a variable delay circuit which can control the delay by 5 ps resolution. The detecting range of the transceiver is from 0.15 m to 8.4 m. The measurement results show that the maximum error is 3.75 mm.(More)
In this paper, we propose a standing-wave push-push voltage-controlled oscillator (VCO) using a transmission-line (TL) resonator that covers a frequency range of 151-174 GHz. By properly distributing negative g<sub>m</sub> cells in the TL resonator, a wide frequency tuning range with low phase noise can be obtained. The electrical length of the TL resonator(More)