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Local Oscillator (local + oscillator)

Distribution by Scientific Domains

Engineering	100%

Selected Abstracts

Nonlinear simulation of mixers for assessing system-level performance

INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 4 2005
Nuno B. Carvalho
Abstract This article deals with nonlinear simulation methods intended to evaluate the impact of mixer nonidealities on the performance of a wireless system. Behavioral models capable of accurately describing the mixer's nonlinear dynamic features at the system level are currently unavailable. The possibility of using alternative circuit analysis techniques to reach this goal is discussed. After a brief review of existing mixer analysis methods, the focus is directed to the techniques amenable to efficiently handling periodic carriers modulated by complex stochastic signals. In particular, it is shown how multi-envelope transient methods coupled with a three-dimensional harmonic-balance engine can model a nonlinear dynamic mixer excited by a modulated RF signal accompanied by a strong adjacent channel interferer and with a local oscillator corrupted by phase noise. © 2005 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2005. [source]

Coherent detection for spectral amplitude-coded optical label switching systems

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 12 2010
Alexey V. Osadchiy
Abstract Coherent detection for spectrally encoded optical labels is proposed and experimentally demonstrated for three label tones spectrally spaced at 1 GHz. The proposed method utilizes a frequency swept local oscillator in a coherent receiver supported by digital signal processing for improved flexibility and upgradeability while reducing label detection subsystem complexity as compared with the conventional optical autocorrelation based approaches. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2732,2735, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25585 [source]

A low local oscillator power K-band mixer based on tunneling diodes

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 4 2009
Iacopo Magrini
Abstract In this article, we will demonstrate a low local oscillator (LO) power K-band mixer based on a tunneling diode technology. Due to its unique diode characteristics, no DC supply is needed, whereas an LO power as low as ,2 dBm is required for nominal functionality. The energy-efficient MMIC prototype integrates a pair of heterojunction interband tunnel diodes and a 90° coplanar broadband coupler. The prototype is optimized within the 19,26 GHz band, with an IF ranging from zero to 7 GHz. In addition, when compared with other mixers, it has the lowest LO power requirement with a conversion loss ranging from 6 to 10 dB, an input compression point of ,3 dBm and an intercept 2nd and 3rd order intermodulation point of 22 and 12 dBm, respectively. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1140,1143, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24228 [source]

A 26,38 GHz millimeter-wave band APDP sub-harmonic mixer

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 8 2008
Shu-Jenn Yu
Abstract A 26,38 GHz millimeter-wave (MMW) band sub-harmonic mixer has been designed using a 0.15-,m GaAs pseudomorphic high-electron-mobility transistor (pHEMT) technology. The anti-parallel diode pair (APDP) configuration as the basic unit in this sub-harmonic mixer design to suppress the fundamental frequency signals is used. The radio-frequency (RF) and the local oscillator (LO) signals are imported by two Lange couplers in the proposed design, with four pairs of APDPs connected in a ring structure. Superior RF/LO-to-IF (intermediate-frequency) and 2LO-to-RF/IF isolations have been achieved. The sub-harmonic mixer circuit has also exhibited excellent conversion loss of 13.7 dB with LO power of 13 dBm. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2135,2138, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23595 [source]

A 3.1 to 5 GHZ CMOS RF transmitter for direct-sequence code division multiple access applications

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 12 2007
Bon-Hyun Ku
Abstract An ultra-wideband RF transmitter with local oscillator (LO) leakage reduction method for direct-sequence code division multiple access (DS-CDMA) is presented. To achieve ultra-wideband gain flatness, the method of combining two shunt-peaking loads with different resonant frequencies is used. A double balanced mixer with a linear transconductance stage is used to increase the linearity of the mixer. To reduce the LO leakage at the output port, an additional DC feedback loop is applied to the linear transconductor. Measurement results show 9.5 dB gain with ±0.8 dB variation over 3.1,5 GHz range. The output P1dB is approximately ,3 dBm and the output IP3 is more than 9.8 dBm for a frequency greater than 3,5 GHz. By the LO leakage reduction method, the LO leakage output power is 5 dB lower than without it. The transmitter consumes 54 mW with a 1.8 V supply and is realized with a 0.18 ,m RF CMOS technology. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 3140,3145, 2007; Published online in Wiley Inter-Science (www.interscience.wiley.com). DOI 10.1002/mop.22960 [source]

A 16-GHz CMOS differential Colpitts VCO for DS-UWB and 60-GHz direct-conversion receiver applications

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 10 2007
C.-C. Lee
Abstract A 16-GHz CMOS differential Colpitts VCO fabricated with the 0.18 ,m 1P6M process is presented. The 16-GHz VCO is a good choice for the local oscillator (LO) circuit of the UWB or 60-GHz WPAN direct conversion receiver. The VCO is composed of a PMOS transistor-pair core circuit and two source follower output buffers. The VCO can operate at 16.5 GHz, and the measured phase noise at 1-MHz offset is ,115 dBc/Hz. The power consumption of the VCO core is 12.6 mW. Compared with previous reported works, this VCO has an output power of ,0.9 dBm and about 800-mV output peak-to-peak voltage swing of the VCO core at 16.5 GHz. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2489,2492, 2007; Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/mop.22742 [source]

A CMOS subharmonic mixer with input and output active baluns

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 12 2006
Brad R. Jackson
Abstract A CMOS 0.18 ,m subharmonic mixer is experimentally demonstrated that uses active baluns at the local oscillator (LO) and RF inputs, as well as at the output. With this subharmonic mixer, a 2.1 GHz RF input and a 1.0 GHz LO input produce a 100 MHz output signal. The conversion gain is 8 dB, the LO and RF input reflection coefficients are better than ,10 dB, and IIP3 is ,8.5 dBm. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2472,2478, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21957 [source]