The Experts below are selected from a list of 2544 Experts worldwide ranked by ideXlab platform
Songcheol Hong - One of the best experts on this subject based on the ideXlab platform.
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a w band 4 ghz bandwidth phase modulated pulse compression Radar Transmitter in 65 nm cmos
IEEE Transactions on Microwave Theory and Techniques, 2015Co-Authors: Juntaek Oh, Jingyu Jang, Songcheol HongAbstract:This paper presents a fully integrated W-band 4-GHz bandwidth (BW) pseudo-noise (PN)-coded pulse compression Radar Transmitter (TX) in a CMOS technology. The PN-coded pulse compression scheme is adopted to obtain high spectral density and to lower the TX leakage using a 63-bit PN code generator based on linear feedback shift registers. We propose a sub-harmonic pumped pulse former and a pulsed power amplifier for high TX efficiency with the suppression of local oscillator (LO)/2LO leakage. A frequency synthesizer including a frequency divider chain generates a sub-harmonic LO signal, as well as a 5-GHz digital clock. Digital blocks with the PN-code generator are synchronized with the clock signal, which makes all pulses start with the same phase. The proposed TX achieves 14.5-dBm maximum output power with the tuning range of 75–81.5 GHz, and the phase noise is ${-}{\hbox{95.2}}$ dBc/Hz at a 1-MHz offset in the range of LO frequencies. In pulse mode, it generates a 4-GHz BW RF pulse signal, which corresponds to a range resolution of 7.5 cm, and the average dc power dissipation is 160 mW.
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a k band cmos uwb Radar Transmitter with a bi phase modulating pulsed oscillator
IEEE Transactions on Microwave Theory and Techniques, 2012Co-Authors: Songcheol HongAbstract: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 oscillator. The VDL allows a high range accuracy level of several millimeters. Asymmetric signals generated by the baseband control signal generator can control the phase of each output pulse. Because the pulsed oscillator operates only for the duration of a pulse, it has an extremely low level of DC power consumption and no LO leakage. It is fabricated with 0.13-μm CMOS technology and a chip with dimensions of 0.98 mm × 0.69 mm. The output spectrum is centered at 26.0 GHz, and the pulse width is controllable from 280 to 680 ps. The peak output power is about 2 dBm.
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A $K$ -Band CMOS UWB Radar Transmitter With a Bi-Phase Modulating Pulsed Oscillator
IEEE Transactions on Microwave Theory and Techniques, 2012Co-Authors: Songcheol HongAbstract: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 oscillator. The VDL allows a high range accuracy level of several millimeters. Asymmetric signals generated by the baseband control signal generator can control the phase of each output pulse. Because the pulsed oscillator operates only for the duration of a pulse, it has an extremely low level of DC power consumption and no LO leakage. It is fabricated with 0.13-μm CMOS technology and a chip with dimensions of 0.98 mm × 0.69 mm. The output spectrum is centered at 26.0 GHz, and the pulse width is controllable from 280 to 680 ps. The peak output power is about 2 dBm.
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A 24-GHz CMOS UWB Radar Transmitter With Compressed Pulses
IEEE Transactions on Microwave Theory and Techniques, 2012Co-Authors: Jaemo Yang, Songcheol HongAbstract: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, which operates as a switch to generate a pulse modulated carrier signal and a bi-phase modulator for pulse compression, is proposed. The proposed Transmitter achieves 4-GHz output signal bandwidth, which means a minimum range resolution of 7.5 cm, and the total dc power dissipation is 63 mW.
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A CMOS Ultra-wideband Radar Transmitter with pulsed oscillator
2010 IEEE Radio Frequency Integrated Circuits Symposium, 2010Co-Authors: Songcheol HongAbstract:A design of Ultra-wideband (UWB) Radar Transmitter is presented. The Transmitter which uses a pulsed oscillator consists of pulse generator, switching buffers and control signal generator. The control signal generator includes modulators of binary-phase shift keying (BPSK) and pulse position modulation (PPM) for spreading the spectral lines. It is fabricated using 0.13 μm CMOS technology and the chip size is 910 × 485 μm2. The output spectrum is centered at the 22.0 GHz with the 10-dB bandwidth of 2.48 GHz and the pulse width of output pulse is tunable from 630ps to 830ps. Also, the BPSK and PPM modulations are confirmed. In conclusion, the generated pulse complies with FCC's spectral mask.
M.p.j. Gaudreau - One of the best experts on this subject based on the ideXlab platform.
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Solid-state Radar Transmitter upgrades
Conference Record of the Twenty-Sixth International Power Modulator Symposium 2004 and 2004 High-Voltage Workshop., 2004Co-Authors: M.a. Kempkes, P.d. Brown, T.j. Hawkey, I.s. Roth, J.m. Mulvaney, M.p.j. GaudreauAbstract:In this paper, we present summaries of our work in developing solid-state components for four Radar Transmitter modulator upgrades. While each Transmitter is uniquely specified, the modulator upgrades share the common approach of replacing vacuum tube switches with reliable, flexible high voltage solid-state technology.
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Radar Transmitter upgrades
Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786), 2004Co-Authors: M.a. Kempkes, P.d. Brown, J.a. Casey, M.p.j. GaudreauAbstract:This paper summarizes DTI's work in developing components for several different Radar Transmitter upgrades. The systems discussed include the AN/SPS-49 long range air surveillance Radar, the Cobra Judy X-band systems, and the AN/SPQ-9A Radar. The new technology is a viable and cost-effective replacement for obsolete components. Further, it improves the reliability of the Transmitter and delivers better protection to the RF amplifier (klystron, TWT, etc.).
Jaemo Yang - One of the best experts on this subject based on the ideXlab platform.
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A 24-GHz CMOS UWB Radar Transmitter With Compressed Pulses
IEEE Transactions on Microwave Theory and Techniques, 2012Co-Authors: Jaemo Yang, Songcheol HongAbstract: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, which operates as a switch to generate a pulse modulated carrier signal and a bi-phase modulator for pulse compression, is proposed. The proposed Transmitter achieves 4-GHz output signal bandwidth, which means a minimum range resolution of 7.5 cm, and the total dc power dissipation is 63 mW.
M.a. Kempkes - One of the best experts on this subject based on the ideXlab platform.
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Solid-state Radar Transmitter upgrades
Conference Record of the Twenty-Sixth International Power Modulator Symposium 2004 and 2004 High-Voltage Workshop., 2004Co-Authors: M.a. Kempkes, P.d. Brown, T.j. Hawkey, I.s. Roth, J.m. Mulvaney, M.p.j. GaudreauAbstract:In this paper, we present summaries of our work in developing solid-state components for four Radar Transmitter modulator upgrades. While each Transmitter is uniquely specified, the modulator upgrades share the common approach of replacing vacuum tube switches with reliable, flexible high voltage solid-state technology.
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Radar Transmitter upgrades
Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786), 2004Co-Authors: M.a. Kempkes, P.d. Brown, J.a. Casey, M.p.j. GaudreauAbstract:This paper summarizes DTI's work in developing components for several different Radar Transmitter upgrades. The systems discussed include the AN/SPS-49 long range air surveillance Radar, the Cobra Judy X-band systems, and the AN/SPQ-9A Radar. The new technology is a viable and cost-effective replacement for obsolete components. Further, it improves the reliability of the Transmitter and delivers better protection to the RF amplifier (klystron, TWT, etc.).
L.e. Atlas - One of the best experts on this subject based on the ideXlab platform.
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Optimization of time and frequency resolution for Radar Transmitter identification
1999 IEEE International Conference on Acoustics Speech and Signal Processing. Proceedings. ICASSP99 (Cat. No.99CH36258), 1999Co-Authors: B.w. Gillespie, L.e. AtlasAbstract:An entirely new set of criteria for the design of kernels for time-frequency representations (TFRs) has been previously proposed. The goal of these criteria is to produce kernels (and thus, TFRs) which will enable accurate classification without explicitly defining, a priori, the underlying structure that differentiates individual classes. These kernels, which are optimized to discriminate among multiple classes of signals, are referred to as signal class-dependent kernels, or simply class-dependent kernels. Until now, our technique has utilized the Rihaczek TFR as the base representation, deriving the optimal smoothing in time and frequency from this representation. Here the performance of the class-dependent approach is investigated in relation to the choice of the base representation. Classifier performance using several base TFRs is analyzed within the context of Radar Transmitter identification. It is shown that both the Rihaczek and the Wigner-Ville distributions yield equivalent results, far superior to the short-time Fourier transform. In addition, a correlation reduction step is presented. This improves performance and extensibility of the class-dependent approach.
