superb approach, DRO is not affordable due to narrow/fixed frequency characteristics for satellite com applications we are looking for 11.8-12 GHz planar VCO for SATCOM applications. could not find this model in the catalog, can author give us the availability of this part? regards, Nijhaman

Ulrich, i like this manuscript, well written and self-explanatory. Thanks, - Putin Jamdagni

informative article but need prerequisite knowledge of advance mathematics...

Hi Ajay, Good work,scientific flavor, and state-of-the-art approach !!! Rgds, Jeena

Dr. S. Jeena, Senior Scientist, Delhi

what kind of bandwidth we expect in IC version versus disrete circuits, which are described in this paper.

good article but very difficult to correlate mathematical derivation pertaining to noise reduction approach as cited in the second part. like to read extension of this paper if any in future.

Readable but not easily digestable. I am impressed with the mathematical part of this paper that makes sense while correlating conventional approach to new one.

We have immidiate requirement of 11.2-11.8 GHz VCO in 0.3x0.3 inches size. We have limitation in supply voltage and current (Vcc=3V, Ic=20mA) but flexible for tuning voltage. Can this technlogy provides solution for lower supply voltage? The phase noise performance is -95 dBc/Hz @ 100 kHz offset. David Solanki RF Component, Tokyo

Ulrich, Outstanding paper. What is maximum operating frequency of this technology? What we understand that physical dimension of the planar resonator may dictate the over all Q factor and performance. BiCMOS process is the technlogy to go for this kind of configuration for a given cross-coupling in integrated circuit.

paper makes sense but i am not sure about the thermal stability. can authors explain about the thermal drift (ppm ???), and how one can control drift in IC. PLL based design can control the thermal driftb(any idea???).

What is chip dimension, We are looking for 0.25x0.25 inches size for our production units. Quantity can be several thousands???

This work attracts me, although it's bound to be big turn-around till we get chip in hand for commercialization and replacement of existing DROs market. John, RFMD

This work attracks me, although it's bound to be big turn-around till we get chip in hand for commercialization and replacement of existing DROs market. John, RFMD

Dear Rohde, et.al, Can we use your circuit layout for integrated circuit for my educational research work? If yes, then advance thanks. If not then what I'm supposed to do for getting permission. This is purely academic work and will be properly referenced with the patent number as shown in your layout. Dr. T. Rukediza, Brazil

Ulrich, let me concur first that this is superb paper on planar resonator based signal sources. As you described about the novel MCSTPR approach, example tunable DCO/DXO VCOs using a SiGe heterojunction- bipolar-transistor (HBT) active device (a model BFP 740 from Infineon) were fabricated on Rogers substrate material with a dielectric constant of 3.38 and thickness of 30 mils (microstripline); can we understant that the phase noise performance and other characteristics will remain unchanged in other technologies such as GaAs or BiCMOS. Please comment, may be other readers might have similiar queries on this matter. Thanks, Prof. J. Bahal

Authors may like to extend this article in part-III, and describe in detail about the technological pitfalls while selecting processing (GaAs,SiGe, BiCMOS,and other possible choice). This part is just Wow !!! First time reading, it was boring but in second time it was interesting, and while reading third time, I am now fascinated with this article.

New dimension and new approach...both part of the article generates immense interest while reading...

Can we get samples for my PhD work, we are interested to build point to point radio using 0.3x0.3 inches VCO (11.8-12.2 GHz). Thanks, Rajeev Agrawal Caltech,USA

We seldom find state of the art work in journal, but this is solid piece of work that has significant vaues in electronic industries. Author's work will be referenced in my article (IEEE Journal of solid state), and I convey my personal thanks to Ulrich.

state of the art article but real breakthrough... M. Sundarajan Prof., EED, Delhi

read both parts but still not clear cut answer is given about the technology transition from discrete to integrated. authors may like to address this issues in next part for clear understanding. i read author's oscillator book, found some useful mathematical derivation, which is helping is understanding this article.

This article is simply great! this is the real piece of work in printed coupled resonator VCO that can be seamlessly transformed into integrated oscillators. I read both part of the papers and previous papers on the subject by the authors and there is much more to know about the concept of mode coupling. It is well organized, to the point, and fresh for new RF engineers who are working in this field.

Ulrich, Keep it up, solid piece of design work... Rgds

Can authors highlights drawback of this approach. This is a solid piece of design work that contains high level of mathematics with clear correlations what they are talking about. We seldom find this kind of paper that has mathematical derivation in support of CAD simulations and experimental results. As describe in part-I and part-II, we understand design approach but fail to digest the concept of Q factor in IC, which is bound to degrade, resulting poor phase noise. Would it be possible to you to describe the concept of compensating/nullifying the Q degradation phenomena in lossy IC substrate. FYI, this techniques as a whole would change the design philosophy of integrated TX-RX circuit; authors are highly appreciated for their innovative and novel concept utilized in this research work. Dr. Roshan Giakwad Analog Devices, Bangalore

Can authors highlights drawback of this approach. This is a solid piece of design work that contains high level of mathematics with clear correlations what they are talking about. We seldom find this kind of paper that has mathematical derivation in support of CAD simulations and experimental results. As describe in part-I and part-II, we understand design approach but fail to digest the concept of Q factor in IC, which is bound to degrade, resulting poor phase noise. Would it be possible to you to describe the concept of compensating/nullifying the Q degradation phenomena in lossy IC substrate. FYI, this techniques as a whole would change the design philosophy of integrated TX-RX circuit; authors are highly appreciated for their innovative and novel concept utilized in this research work. Dr. Roshan Giakwad Analog Devices, Bangalore

Hi Ulrich, I enjoyed reading your paper in which part-I introduces the mathematical basis for designing integrable oscillator (inexpensive alternative of DRO, and subsequent verification of the design via measured data. The second part adds practical circuits using MCSTPR theory to classical terminology, expands Leeson noise model to dynamic phase noise model, and includes beta opt and mopt concept for oscillator analysis. This piece of work can ca help readers, provided some insights for transformations from discrete to the integrated circuits while maintaining comparable performances. My PhD students are building some of the example circuits for academic purpose with a proper reference (not for commercial use), will update you the outcomes of your discrete example circuit in IC configurations. Regards, Prof. T. Jacob

New approach

New approach

This part (II) demonstrates the feasibility of printed resonator based regenerative circuits that can partially substitute the DROs (if we need more tuning range).

I enjoyed reading both parts (part 1 and 2) of the article, would like to express my thanks to authors who are pioneer in VCO's field. It is but natural to expect breakthrough in technology but and it seems that gradually printed structures are winning other territories in faster pace than expected in reality. The only risk what we anticipate is the thermal stability and real challenge witnessed by design communities to compensate the frequency drift due to changes in temperature and associated cross-couplings and substrate noise in integrated VCOs.