Tutorial-38: Harmonic Balance Simulations

[@junzhang8214]

You have simply the best explination on ADS on KZbin. Thank you!

[@BhargavaAnurag]

You're very welcome!

[@GiangPham-yq3nf]

i'm a beginner so it's very useful for me. Thank you for taking the time to make this video

[@BhargavaAnurag]

You're very welcome!

[@rjhall351]

This is really good content, thank you for putting all of these tutorials together.

[@BhargavaAnurag]

You're very welcome!

[@rjrodrig]

As usual... great information

[@BhargavaAnurag]

Thanks for watching

[@yaoyucao9601]

Hi Bhargava, I am a big fan of you and have watched all your videos several times, whenever you are available, could you please create some tutorials of nested die, laminate, PCB technology setup? Also if possible, can you create some tutorials about electrical-thermal simulation tutorials including thermal layer stack up setup? Thanks a lot !!!

[@BhargavaAnurag]

Hi Yaoyu, You can refer to this tutorial for multi-tech simulation, this videos illustrates concept of Smart Mount which is much easier as well as superior to older nested technology setup: kzbin.info/www/bejne/jZqalp2Bp8yFoq8 I will cover Electrothermal simulations in near future tutorials...👍

[@emmanuelmuganza3426]

great video sir, How did you calculate the components values for the feedback stability network ? thank you !

[@BhargavaAnurag]

I simply used S-Par simulation and tuned/optimize the stability component values.

[@sirdancealot2645]

Hello Mr. Bhargava. Thank you for these tutorials. They are very helpful in many ways. I have one consideration of the videos and that is your voice is too low. I'm actually using headphones at max level to hear you out. Can you please increase the input power sensitivty of your mic for next videos or perhaps boost the output? Thank you very much.

[@BhargavaAnurag]

Hi, This is surprising because I test the voice before every upload and haven't heard any other complaint about this. I can hear it properly on my side. Could you recheck audio settings on your side? You do have the volume control on the video as well as on the PC Audio Mixer, make sure both are set to proper levels to improve audio quality/level.

[@Mouftih8]

Great eplaining sirm I would like to thank you for your easy tutorials you're a life saver Thank you so much!

[@BhargavaAnurag]

You're very welcome!

[@Mouftih8]

@@BhargavaAnurag Thank you :D please sir I have a small question, How can I plot the derivatives (transconductances) of a transistor (g1,g2 and g3) ? I need them for my "Derivative Superposition" research and thank you in advance

[@rfengineering2022]

Thank you sir. Your tutorials are awasome

[@BhargavaAnurag]

Glad you like them!

[@jemvajemva1]

Thank for the content Mr. Bhargava. Which version of ADS are you using here? ADS 2019?

[@BhargavaAnurag]

Hi Mario, The content explained in this video would be applicable for latest as well as earlier releases of ADS.

[@bios546]

ye know, It feels more like 2minutes to me 'cause the way you present info is pretty flawless.

[@BhargavaAnurag]

Appreciate your feedback...👍

[@raphaelcardoso7927]

Can we use this type of simulation to evaluate an oscillator? So without an input source

[@auburn360guy7]

Can you please tell us what is the {o} means in front of the series gate resistance right next to 15 ohm

[@BhargavaAnurag]

{o} represents the optimizable variable in your design and this will be used when you run Optimization.

[@aquibsayed4251]

Nice video. But to calculate the output power is dBm(vout) sufficient ? I thought dBm(vout) is only converting the output voltage into dBm. Can we also use a P_probe at the output instead and use wtodbm(P_probe.p) equation ?

[@BhargavaAnurag]

Sure, you could do that and results of both approaches will be similar...👍

[@SaiKrishna-ru1qd]

Hello Mr.Bhargava your videos helped me a lot I have question in which I have some issues in solving can you please do a video or can you provide the schematic for Design, by synthesizing its matching networks, a Class AB large-signal power amplifier based on the Broadcom ATF-35143 pHEMT model. In particular, maximize the output power at f=2 GHz. Evaluate the THD and the 1-dB compression point.

[@BhargavaAnurag]

Hello Sai, The device that you mentioned is a low noise device more suited for LNA purposes and I am not sure why are you using it for PA? Anyways, for max power, you can find out the required impedance from a LoadPull analysis, and then it is no different than doing a normal impedance matching. For 1-dB compression point, TOI/IP3 etc kindly watch the Harmonic Balance and 2-Tone tutorial videos. We will cover all these topics when I create a tutorial for PA design in the near future....

[@SaiKrishna-ru1qd]

@@BhargavaAnurag thank you so much actually i got this question in my exam which i was anable to do so i did watch the harmonic balance video helped me a lot

[@BhargavaAnurag]

Sure, if you want to do class AB operation then select Bias point near cut-off region and rest of the process will be same. Also you can plot voltage & current at different nodes to see how the conduction is happening to prove the point that it is indeed working in Class AB mode.... Hope this helps....

[@파시러]

Thank you for this video. where can I find this design kit?? How to use the demo kit in this video?

[@BhargavaAnurag]

It is included in the ADS itself. When you create a new workspace, click ok "Change Libraries" and in the pop up window you will see Demo Kit Non-Linear, simply select it to be added to your workspace...😊

[@ismailk7070]

Hello Sir, I am a beginner. It is very useful for me to understand HB analysis. While I am following your steps, I got output at 0 frequency also in harmonic plots. I don't understand how it is happening.

[@BhargavaAnurag]

whenever you run HB simulation you will always have power at DC or 0Hz unless you have a coupling capacitor in series to the RF path.

[@saurabhshukla1490]

Sir, I have a question for device stability, can provide the stability only from adding the resistance component along with the transistor then after it could increase the stablity factor by the tunning of resistance value.Is any feasibility there to do this ?

[@BhargavaAnurag]

Yes, a resistor is a key component for achieving stability but again there are various techniques and considerations you need to take while designing a stability network. I will cover all that when we start with LNA circuit design shortly but I need to cover other basics before we can get to that point and that's what I am doing right now.

[@saurabhshukla1490]

Okay Sir I got your point...one more thing ..if I am working on millimeter wave frequency then what type of component should add there like lumped or distributed.. should I use chip register?

[@eeengineers3958]

Sir can you provide any design tutorial for RF Frequency Multipliers?

[@BhargavaAnurag]

Hi, I wrote a article in Microwave Journal many years ago for Frequency Multipliers, see it here: www.microwavejournal.com/authors/997-anurag-bhargava-isro

[@ilyassvino1154]

Hello , I would like to ask you if i am using 2 P Tone sources , let say onP tone source for RF and the other one for OL. Do I need to use 2 palettes ? that is one for each P Tone. Greeting from Morocco, thank you

[@BhargavaAnurag]

I don't understand your question fully but you can watch video 39 that talks about 2-tone analysis and that should answer your question

[@brothers6196]

hello sir i have one confution.By analysing a graph, where there is zero gain at 0 db ( graph of 5 hormonics ) what you actually conclude from that graph..??? all other graphs are understood.

[@BhargavaAnurag]

That graph shows you power output of fundamental frequency as well as its harmonics which will be important for circuit like Power Amplifier where it is intended not only to achieve output power on the desired fundamental frequency but also to make sure harmonic power should remain below a certain threshold.

[@Muhammadali-jd6td]

Hello Mr. Bhargava, can you please elaborate how did you obtain the RLC feedback and series gate resistance values and How can we stabilize any switch/active component?

[@BhargavaAnurag]

Kindly go thru the LNA design tutorial video to understand more on this

[@faruktutorial943]

@@BhargavaAnurag Dear Sir, I have gone through LNA tutorial 9-10 videos but it could not solve the problem. First, you used series resistance at the input and output sides separately. Then, you deactivate input resistance, and connect RC network towards the ground. The values were picked previously and there was no RLC feedback. kzbin.info/www/bejne/n3jOiKGsqq16ftk

[@peterkern7757]

Hi sir I want to ask how can I add two signals in ADS, for example I want to add PTRF_Pulse and VtSine together as an input signal, how can I do it

[@BhargavaAnurag]

Hi, I am not sure about the application but you could probably use Power Splitter/Combiner from System-Passive library.

[@Phanphuc2101]

Hi sir. I can't find Demo_netlist_include. Can u help me?. Thank you!

[@BhargavaAnurag]

Pls reach to Keysight Tech support team at [e-mail]

[@peimanparand]

awesome thanks so much

[@allenxiao9895]

Why once I change the order in the HB setting to see more spectrum, the V/I (mag) of fundamental also changes?

[@BhargavaAnurag]

Hi Allen, It is difficult to comment as it largely depends on how much change you are seeing. Little bit of change is expected as you have more harmonics where the power is distributed which is the true nature of your circuit but in a typical circuit you won't see any appreciable change after 5th harmonic. Sometimes, this can change due to your circuit config. I would recommend you to connect with Keysight tech support team to show them your circuit and they can comment on the root cause.

[@allenxiao9895]

@@BhargavaAnurag thanks for the reply. The changes is mainly on the satiation range, which seems to me that when selecting order, not only to show higher order hams, it also to include higher order calculation for accurate foundamental value, right?

[@BhargavaAnurag]

I notice typo errors so difficult to understand complete meaning but yes you should include atleast upto the 5-7 harmonics during HB for better accuracy or may be more depending on what kind of circuit you are simulating.

[@sreepadaneeha]

I am trying to perform HB simulation of frequency doubler design to generate 2nd harmonic, can you please help me with the steps? Thank you in advance

[@BhargavaAnurag]

There is no special effort there other than to setup a HB analysis with sufficient Order so that all needed harmonics are captured. For more details, contact your local Keysight tech support team for help

[@qtoan96]

Hi sir, how can you plot PAE from the schematic from this video?

[@qtoan96]

what is the equation for plotting PAE on the same DDS? TIA!

[@sukhpreetsingh9011]

Hello Sir I want to plot gain, efficiency with respect to frequency instead of power in ADS as I am keeping swept parameters frequency but not able to plot it. It will be great help for me. Thanks in advance

[@BhargavaAnurag]

Hi Sukhpreet, It shouldn't be too difficult. Here is what I would suggest to keep it simple: 1. Setup a Parameter Sweep for frequency variable. 2. Mention this variable in HB Simulation Controller as well as the P_1Tone source used in the design 3. Run simulation and plot the efficiency. You will need to filter out the efficiency from the output node e.g. Efficiency[::.1] where :: represents all the fundamental frequency points and 1 represents the fundamental frequency only as results will also contain Harmonic Frequencies so you may want to only plot data for fundamental frequency. For more info, kindly refer to earlier videos in this playlist on Multi-dimensional Data Processing video. If still can't make it working then contact local Keysight Tech Support team for help.

[@sukhpreetsingh9011]

@@BhargavaAnurag As per your suggestion I am able to plot w.r.t frequency but now I am getting efficiency, gain graphs at each input power value and this input power pin I have set as parameter to sweep in HB sweep tab. Can you please help how can I get variation w.r.t only one variable frequency.when in make fixed power input value in my design and only one swept variable frequency then it shows nothing on graphs

[@sukhpreetsingh9011]

@@BhargavaAnurag Thanks sir able to plot w.r.t frequency.

[@brothers6196]

hello sir..thanks for this tutorial. plz also make a video on how can we play with phase of wave in Rf . i am working on a poject 1×4 power couplers/splitter.power splitting is on coupling not all ports are directly connecting to main line. somethinh like this _!_!_!_| Despite kreping same length between all four ports phase is not same ..?? plz help me i stuck here for long time..???

[@BhargavaAnurag]

That should be pretty easy. Use one of the output port as reference, calculate the delta phase difference between other ports and adjust the line lengths accordingly. Sometimes you may need to reduce length little bit and sometimes you need to increase but if you have done it right it would be very small amount of adjustment needed.

[@brothers6196]

sir i have keep the lenght between all ports exactly same..?? Does ADS give error in some design..???

[@BhargavaAnurag]

@@brothers6196 Keep length of each path exactly the same is not a requirement as phase can change a little bit at various discontinuities such as TEE, BEND etc so you need to compensate the small phase difference based on your design and the delta difference observed.

[@faruktutorial943]

Although I added the I_probe block in the right direction and options block settled to 16.85 simulation temperature, I cannot plot the Iout graph. It even did not appeared in the list of parameters that can be plotted.

[@BhargavaAnurag]

I am not sure what relation 16.85 temperature has with I_Probe? Iout is the name of the current probe in my case and it will appear in the dataset based on the name of the current probe which by default is I_Probe1 so you should see something like I_Probe1.i in the dataset....

[@Techifly]

sir, my gain is coming in negative... what is the solution? please help

[@BhargavaAnurag]

Kindly check your simulation setup. If you can't resolve it yourself then contact your local Keysight tech support team for help.

[@Techifly]

@@BhargavaAnurag thank you sir for the reply.. These videos are really helpful for us.

[@faruktutorial943]

I have the same problem, but I used CG2H40035 model; and its characteristics is different. Unfortunately, the feedback network does not fit into my situation; and I could not learn step by step determination of R-L-C values from previous videos.

[@UzairKhan-mu7pw]

Sir how to find output voltage of rectifier circuit?Also how to match rectifier circuit please?

[@BhargavaAnurag]

To simulate rectifier you can run Transient simulation and place the wire label at the required node. Its pretty east to do. I am not sure what do you mean by "match the rectifier circuit"?

[@user-lk1os1sb4u]

increase your voice volume, I cannot hear you!

[@BhargavaAnurag]

Sorry about that but it comes out fine on my side as well as others. Could you check you KZbin video volume or PC volume settings?