Abstract:Phase-locked loops (PLLs) for ultra-wideband, low noise, and linear frequency ramp synthesis exhibit a wide variation of the loop gain, if no compensation method is applied. This impairs the performance of the PLL and the corresponding microwave measurement systems. To overcome the disadvantages of existing compensation techniques, we present a new compensation method based on a phase-frequency detector gain modulation. This offers low hardware complexity and avoids additional noise. Furthermore, we present an… Show more
“…It should be noted, that the 65 GHz measurement was limited by the equipment, while the steep K VCO also becomes difficult to account for. To improve the results at the low signal frequencies, the feasibility of a loop gain compensation as we presented in [23] will be investigated in future works. Fig.…”
Radio telescopes are among the applications with the highest demands on a local oscillator (LO), which is used to receive and process the signals coming from the sky. Therefore the modules providing the required LO signal have traditionally been big and complicated. To overcome this disadvantage, we implement our own integrated frequency synthesizer inside a small LO module in this article. With this synthesizer we are able to achieve a jitter of only 50 fs integrated from 10 Hz to 2.5 GHz offset at a carrier frequency of 75 GHz. This is in part achieved by a very low in-band phase noise of −111.8 dBc at 10 kHz offset. The stabilizable frequency range is 62–88 GHz. Thus achieving promising results to fulfill this very demanding task with integrated frequency synthesizers in the future.
“…It should be noted, that the 65 GHz measurement was limited by the equipment, while the steep K VCO also becomes difficult to account for. To improve the results at the low signal frequencies, the feasibility of a loop gain compensation as we presented in [23] will be investigated in future works. Fig.…”
Radio telescopes are among the applications with the highest demands on a local oscillator (LO), which is used to receive and process the signals coming from the sky. Therefore the modules providing the required LO signal have traditionally been big and complicated. To overcome this disadvantage, we implement our own integrated frequency synthesizer inside a small LO module in this article. With this synthesizer we are able to achieve a jitter of only 50 fs integrated from 10 Hz to 2.5 GHz offset at a carrier frequency of 75 GHz. This is in part achieved by a very low in-band phase noise of −111.8 dBc at 10 kHz offset. The stabilizable frequency range is 62–88 GHz. Thus achieving promising results to fulfill this very demanding task with integrated frequency synthesizers in the future.
“…The publications of different tunable oscillators in Table I offer different information. The works [24], [27], [28] and [17] only specify the phase noise at single, but not equal, offset frequencies. Whereas, the publications [19], [20] and [18] show the phase noise only at one or two oscillation frequencies, but as a function of the offset frequency.…”
Section: Resultsmentioning
confidence: 99%
“…First, voltage-controlled oscillators (VCOs) based on an LC tank resonator utilize a varactor to tune the output frequency. On the one hand, the entire VCO can be implemented in a single monolithic microwave integrated circuit (MMIC) [17], [18], which allows for low cost, weight, and size. On the other hand, the continuously tunable relative bandwidth is limited and the phase noise is only moderate [17], [18].…”
Wideband and low-noise tunable oscillators at microwave frequencies are crucial within microwave frequency synthesizers and key to high-end measurement systems based on electromagnetic sensing in the microwave range as well as in the terahertz (THz) and sub-THz range. This paper presents a novel, wideband, and low-noise differential yttrium iron garnet (YIG) tuned oscillator. It is based on a SiGe monolithic microwave integrated circuit and a transmission-type YIG resonator. The integrated circuit contains a fully differential amplifier as a part of the oscillator core. The resonator was realized by two orthogonal, crossed pad-to-pad bonds and an YIG sphere, which is positioned between those bonds and the integrated circuit. To design and optimize the oscillator, an equivalent circuit modeling the resonator was developed. Concerning the tuning range and the phase noise, the results of the circuit simulations are in good agreement with the measurements. Two oscillators with different lengths of the inductive load transmission line were realized. First, the oscillator with a short transmission line offers very high-oscillation frequencies with a tuning range from 32.0 to 48.2 GHz. It exhibits an excellent phase noise of less than −119 dBc/Hz at an offset frequency of 100 kHz for oscillation frequencies up to 42 GHz. Second, the oscillator with a longer transmission line length offers a tuning range from 19.1 to 41.4 GHz. This configuration exhibits an excellent phase noise of less than −120 dBc/Hz at an offset frequency of 100 kHz for oscillation frequencies up to 38 GHz. Index Terms-Low noise source devices, microwave and millimeter wave oscillators, SiGe HBT circuits, ultra-wideband sources devices, yttrium iron garnet (YIG). I. INTRODUCTION M ICROWAVE frequency synthesizers are key to high-end measurement systems based on electromagnetic (EM)
“…Once the choice of the active component is made, it is necessary to have models which describe the performances corresponding to the circuit to be made and this according to the width of the grids for the field-effect transistors (FETs) or the length of the transmitter for the hetero-junction bipolar transistor (HBT) [5]. For instance, in [6], the voltage controlled oscillator (VCO) is based on an liquid crystal (LC) resonator and can be implemented in a single MMIC and itis characterized by low cost, low weight and so low size. However, [7] and [6], the continuously tunable bandwidth is limited and the phase noise only moderate.…”
Section: Introductionmentioning
confidence: 99%
“…For instance, in [6], the voltage controlled oscillator (VCO) is based on an liquid crystal (LC) resonator and can be implemented in a single MMIC and itis characterized by low cost, low weight and so low size. However, [7] and [6], the continuously tunable bandwidth is limited and the phase noise only moderate. In [8], the push-push strategy is applied to coplanar MMIC with InGaPi-GaAs-HBTs, which are known to combine 1/f noise with mm-wave capabilities.…”
novel structure of low phase noise and high output power monolithic microwave integrated circuit (MMIC) oscillator is presented in order to use it in 5G applications. The oscillator is based on the ED02AH process which allows us to design a microwave oscillator keeping a minimum size which is impossible to have it using other technologies since microwave oscillators are sensitive components above 20 GHz. The oscillator is studied, designed, and optimized on a GaAs substrate from the OMMIC foundry using the advanced design system (ADS) simulator in order to obtain a miniaturized oscillator (1.1×1.3 mm<sup>2</sup>) generating two signals of different frequencies f<sub>o1</sub>=26 GHz and f<sub>o2</sub>=30 GHz. The objective is to design an oscillator with high output power and low phase noise while respecting its specifications. The optimization of the proposed microwave oscillator shows satisfying results. Indeed, at 26 GHz and 30 GHz, the output powers are respectively 13.33 dBm and 14.89 dBm. The oscillator produces a sinusoidal signal of 1.5 V and 1.75 V amplitude respectively at 26 GHz and 30 GHz. The oscillator phase noise at f<sub>o1</sub> and f<sub>o2</sub> resonance frequencies using the liquid crystal (LC) resonator shows respectively -109 dBc/Hz and -110 dBc/Hz at 10 MHz offset.
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