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1.
基于高次谐波体声波谐振器(HBAR)的高品质因数(Q)值和多模谐振特性,设计了Colpitts和Pierce两种形式的微波振荡器。采用HBAR与LC元件组成谐振回路的方法,与放大电路构成反馈环路直接基频输出微波频段信号。Colpitts振荡器输出信号频率为980 MHz,信号输出功率为-4.92dBm,信号相位噪声达-119.64dBc/Hz@10kHz;Pierce振荡电路输出信号频率达到2.962GHz,信号输出功率为-9.77dBm,信号相位噪声达-112.30dBc/Hz@10kHz。 相似文献
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《Microwave Theory and Techniques》1984,32(7):719-721
A technique for the design of microwave transistor oscillators is presented in which measurements made on an experimentally optimized amplifier are used to calculate six basis oscillator circuits which yield maximum power output. The procedure has been experimentally verified by the construction of a silicon bipolar transistor test oscillator at 1 GHz. 相似文献
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《Solid-State Circuits, IEEE Journal of》2009,44(7):1950-1958
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Youngoo Yang Jaehyok Yi Bumman Kim 《Microwave Theory and Techniques》2001,49(2):387-390
In this paper, we present a new silicon RF LDMOSFET large-signal model including a self-heating effect. A new empirical channel current model suited for accurately predicting intermodulation distortion is employed. The proposed channel current model can represent transconductance (gm) saturation and rolloff in the continuous manner. It has continuous higher order derivatives for accurate prediction of nonlinear microwave circuit behavior, such as power amplifiers, microwave mixers, oscillators, etc. Using the complete large-signal model, we have designed and implemented a 1.2 GHz power amplifier. The measured and simulated amplifier characteristics, especially the intermodulation and harmonic behaviors, are in good agreement 相似文献
6.
《Solid-State Circuits, IEEE Journal of》1969,4(6):400-408
Because of the excellent results of the noise-loading test on an IMPATT oscillator that is phase-locked to an external FM driving signal, a new microwave amplifier for multichannel FM signals using a synchronized oscillator is proposed. An IMPATT oscillator, injection-synchronized with an FM signal, is regarded as an amplifier and its noise characteristics for multichannel signals are evaluated with the noise-loading method as recommended by the International Radio Consultative Committee. The results show that when this oscillator satisfies the noise characteristics for 960 telephone message channels, it assures a gain of approximately 15 dB at 11 GHz, and in this sense, this oscillator can be regarded as an amplifier for multimessage channels. The degradation of SNR of this amplifier is less than 2 dB. This excellent result is obtained because of the following. In the video band, the modulation suppression of an FM driving signal in the injection-synchronized oscillator, such as the IMPATT, is very small, while the oscillator noise, which dominates the entire output characteristic, is considerably reduced by the synchronizing action of the oscillator. This amplification continues up to the high-frequency range in which this principle of operation applies. 相似文献
7.
Pankiewicz B. Wojcikowski M. Szczepanski S. Yichuang Sun 《Solid-State Circuits, IEEE Journal of》2002,37(2):125-136
A programmable high-frequency operational transconductance amplifier (OTA) is proposed and analyzed. A general configurable analog block (CAB) is presented, which consists of the proposed programmable OTA, programmable capacitor and MOSFET switches. Using the CABs, the universal tunable and field programmable analog array (FPAA) can be constructed, which can realize many signal-processing functions, including filters. A tuning circuit is also discussed. The proposed OTA has been simulated and fabricated in CMOS technology. The results show that the OTA has the transconductance tunable/programmable in a wide range of 700 times and the -3-dB bandwidth larger than 20 MHz. A universal 5×8 CAB array has been fabricated. The chip has also been configured to realize OTA-C 60-kHz and 500-kHz bandpass filters based on ladder simulation and biquad cascade 相似文献
8.
High-performance operational transconductance amplifiers (OTAs) are important in the design of high-frequency analog transconductance-C (g
m
-C) filters. Critical design considerations for OTAs are frequency response, linearity, tuning, output impedance, power supply rejection (PSR), and common-mode rejection (CMR). In CMOS technology, satisfactory OTA design techniques are available, except that the linear input range often is relatively small and the frequency response of the OTA is limited by the intrinsic speed of transistors. In this paper, a new approach is developed to increase the linear input range, and a trade-off between linearity and input range is discussed. A CMOS OTA with less than ±0.4% linearity error over a very large input range is given as a design example. To achieve a very high frequency response, 1m depletion-mode GaAs MESFETs with high intrinsic speed are used to replace MOSFETs. Simple ac compensation, a new technique for output impedance enhancement, and a new tuning method for OTAs with all N-channel devices are used to design a GaAs OTA with very small parasitics and f
–3dB=7 GHz. To improve PSR and CMR, fully balanced structures are used for the OTAs. Design considerations for the interaction of the operation of common-mode feedback (CMF) and tuning are discussed, and improved CMF circuits are proposed. Using the GaAs OTA and considering the frequency limitations imposed by parasitics, the design of a high order ladder filter with 300MHz cutoff frequency is presented as an application. 相似文献
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Pandey P. Silva-Martinez J. Xuemei Liu 《IEEE transactions on circuits and systems. I, Regular papers》2006,53(4):811-820
A 550-MHz linear-phase low-pass continuous-time filter is described. The operational transconductance amplifier (OTA) is based on complementary differential pairs in order to achieve high-frequency operation. A common-mode feedback (CMFB) based on a Class AB amplifier with improved stability at high frequencies is introduced. Results for the stand alone OTA show a unity gain frequency of 1 GHz while the excess phase is less than 5/spl deg/. The filter is based on G/sub m/-C biquads and achieves IM3 <-40 dB for a two-tone input signal of -10 dBm each. The power consumption of the fourth-order filter is 140 mW from supply voltages of /spl plusmn/1.65 V. The chip was fabricated in a standard 0.35-/spl mu/m CMOS technology. 相似文献
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In this paper, a low-phase-noise 67-GHz CMOS oscillator is presented. This inductorless voltage-controlled oscillator (VCO)
employs a combination of standing-wave and travelling-wave oscillators to generate multi-phase outputs. A filtering technique
is used to reduce the phase noise of the VCO. The oscillator achieves a tuning range of 5.2 GHz using a combination of coarse
and fine tuning methods. The proposed multi-phase oscillator is designed and fabricated in a 0.13-μm CMOS process. Operating
at 67 GHz, the VCO consumes 14 mW from a 1.2-V supply and achieves an output phase noise of −95.66 dBc/Hz (−107.89 dBc/Hz)
at a 1 MHz (10 MHz) offset. The chip area is 0.9 mm2. As an application example for the presented multi-phase oscillator, a polar transmitter structure is proposed. The transmitter
is designed for systems that use a circular quadrature-amplitude modulation (QAM) constellation. A specific example of a 16-QAM
transmitter is presented. The desired output phase is chosen by an 8-to-1 multiplexer, and a variable gain amplifier (VGA)
is used to achieve the desired amplitude. Based on post-layout simulations, the 60-GHz 16-QAM transmitter consumes 43.2 mW
from a 1.2-V supply. 相似文献
11.
Eduardo Ortigueira Taimur Rabuske Luís B. Oliveira Jorge Fernandes Manuel M. Silva 《Analog Integrated Circuits and Signal Processing》2017,90(1):101-111
In this paper, the effects that limit the performance of practical implementations of RC relaxation oscillators are investigated. The insights gained are used to suggest a topology for high-frequency quadrature relaxation oscillators with closer-to-optimal performance. The proposed oscillator uses a modified latch to improve the switching speed without increasing the power consumption. Moreover, the new topology avoids static current sources, maximizes the voltage swing and has an active coupling structure without static power consumption that reduces the circuit phase-noise. Experimental results show that the oscillator operates in relaxation mode at 2.4 GHz and achieves a FoM of \(\mathrm {-162\,dBc/Hz}\), which is, as far as the authors know, the best FoM for relaxation oscillators operating in the GHz range. 相似文献
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《Microwave and Wireless Components Letters, IEEE》2009,19(6):395-397
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Veeravalli A. Sanchez-Sinencio E. Silva-Martinez J. 《Solid-State Circuits, IEEE Journal of》2002,37(6):776-781
A pseudodifferential CMOS operational transconductance amplifier (OTA) with wide tuning range and large input voltage swing has been designed for very small GM's (of the order of a few nanoamperes per volt). The OTA is based on a modified four-quadrant multiplier architecture with current division. A common-mode feedback circuit structure has been proposed and designed using floating-gate transistors to handle large differential signals. Large on-chip capacitors are emulated through impedance scaling circuits. The circuits, fabricated in a 1.2-μm CMOS process, have been used to design a fourth-order bandpass filter and a relaxation oscillator. Experimental results are in good agreement with the theoretical results 相似文献
14.
The established method of frequency drift compensation in voltage controlled oscillators (VCOs) resulting from temperature variance involves modulation of control voltage using a non-linear voltage internally generated. An innovative frequency drift compensation scheme for a VCO, based on amplitude control, is described in this paper. Two peak detectors are used to generate voltages representing positive and negative peaks of the sinusoidal driving an error amplifier. The amplifier output controls the delivery of transconductance accessible to the oscillator, thereby keeping the oscillation amplitude steady. Frequency stability has improved to 16 ppm/°C from an uncompensated value of 189 ppm/°C and is applicable where frequency stability requirements are not stringent, such as HS-USB and S-ATA. The temperature stabilized VCO at 2.4 GHz center frequency is prototyped using CMOS technology from ams AG (formerly austriamicrosystems AG). The result obtained from this study indicates that better frequency stability may be achievable if the traditional compensation scheme is preceded by amplitude control. 相似文献
15.
Poobuapheun N. Wei-Hung Chen Boos Z. Niknejad A.M. 《Solid-State Circuits, IEEE Journal of》2007,42(8):1669-1677
An integrated quadrature demodulator with an on-chip frequency divider is reported. The mixer consists of a transconductance stage, a passive current switching stage, and an operational amplifier output stage. A complementary input architecture has been used to increase the transconductance for a given bias current. The circuit is inductorless and is capable of operating over a broad frequency range. The chip was implemented in a 0.13-mum CMOS technology. From 700 MHz to 2.5 GHz, the demodulator achieves 35 dB of conversion voltage gain with 250-kHz IF bandwidth, a double-sideband NF of 10 dB with 9-33 kHz 1/f-noise corner. The measured IIP3 is 4 dBm for a 0.1-MHz IF frequency and 10 dBm for a 1-MHz IF frequency. The total chip draws 20 to 24 mA from a single 1.5-V supply. 相似文献
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《Solid-State Circuits, IEEE Journal of》2009,44(8):2138-2153
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本文研究了一种新型的微波开关.利用震荡电路产生频率为50Hz(占空比为1%)的低频信号,低频信号通过施密特触发器得到10GHz的高频信号,然后通过高频振荡器发射微波束.利用波束障碍原理,当接收振荡器接收到的微波束经过滤波、放大、解调后,控制芯片(MSP430F149)对得到的幅值、低频频率、高频频率等参数进行判断,从而... 相似文献
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《Microwave Theory and Techniques》2008,56(8):1899-1908
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《Electron Devices, IEEE Transactions on》1967,14(9):517-522
Linear microwave amplifiers with continuous power outputs of 100 mW have been constructed utilizing the frequency-independent negative conductance observed externally in Gunn oscillators. This negative conductance is exhibited only in samples containing propagating dipole layers, in other words,n_{0} . L must be larger than 1012cm-2for n-GaAs. The output power obtainable from this amplifier is substantially larger than that from a subcritically doped GaAs amplifier (n_{0} . L < 10^{12} cm-2) becausen_{0} . L can be increased. Power output and efficiency are discussed in terms of n0 andL . The upper-frequency limit for amplification is determined by the time the domain takes to readjust itself after a change of external voltage which leads to an upper limit for thef. L product (about 108cm/s). The essential feature of the amplifier circuit is to provide both a short circuit at the Gunn oscillation frequency and a broadband circuit at the signal frequency. An average gain of 3 dB was exhibited from 5.5 GHz to 6.5 GHz. Gain compression of 1 dB occurred at 60 mW output power with 9 dB gain, while the noise figure was about 19 dB. 相似文献