Search:

Type: Posts; User: ktr

Page 1 of 6 1 2 3 4

Search: Search took 0.01 seconds.

  1. Closed: Re: Lamda equals to how many degrees on smith chart

    1 Ghz - 30 cm wavelength in air Epsilon = 1 -- 15cm wavelength in FR4 Epsilon= 4

    1/sqrt(4) = 1/2 will be the velocity of wave in FR4 when compared to Air.

    Electrical length in terms of S11,S22...
  2. Replies
    4
    Views
    392

    Closed: Re: Suggestion to design a matching network

    I'm not sure if thats what you want, but you can use an RF switch(SP6T or something like that) with a couple nanosec~switch time; and design different matching networks covering different frequencies.
  3. Replies
    3
    Views
    261

    Closed: Re: Layout design book recommendation

    -keep your traces about lambda/10 long in your circuit for phase stability.
    -make sure to do em simulation to observe how your current travels through the PCB.
    -use proper DC-block and RF-choke...
  4. Replies
    4
    Views
    284

    Closed: Re: Microwave amplifier, component distance

    Easiest way for you to learn is, look at an eval board of a commercial amplifier at your frequency of interest. Download it's gerber file, and look at it's via placement and size. Analog Devices and...
  5. Replies
    3
    Views
    204

    [SOLVED]Closed: Re: Using a 0db Attn as termination

    Hello Dr. Volker,



    Thanks for replying. That's the part I'm struggling to figure out, if reasonable. If not properly terminated circulator does not work; hence I thought maybe a 0-db attenuator...
  6. Replies
    3
    Views
    204

    [SOLVED]Closed: Using a 0db Attn as termination

    Hello Microwave Forum,

    I am trying to incorporate a RF power detector in my circuit at C-band to understand if a discontinious cable or a rusty connector exists between my antenna and PA.

    I...
  7. Replies
    2
    Views
    556

    Closed: Re: 90 nm cmos 60 ghz and 130 nm

    you need to sign a confidentiality agreement with a foundry for them to share their production parameters with you. that sort of datasheet is hard to find online.
  8. Replies
    1
    Views
    310

    Closed: Re: group delay of waveguides

    Because, waveguides are also frequency dependent in their own nature. When u design a waveguide or a transmission line, it actually works perfect for a single frequency. So, if your aim is to get a...
  9. Replies
    3
    Views
    1,483

    [SOLVED]Closed: Negative voltage needed in K-band

    Hello,

    I am trying to incorporate a medium power PA into my circuit, which had only positive voltages before that. For this PA, I need to include a negative gate voltage for active bias purposes....
  10. Replies
    1
    Views
    273

    Closed: Re: Loop bandwidth of a Charge pump PLL

    PLL locks the free-running oscillator to a certain frequency using the VCO's tuning voltage pin by adjusting the voltage of that pin. PLL controls the output voltage of the charge pump so that VCO...
  11. Replies
    3
    Views
    644

    Closed: Re: design band stop filter

    Maybe you can search the web for a filter design software like FilPro.
  12. Replies
    6
    Views
    892

    Closed: Re: RF IQ Quadrature modulator

    Maybe you can draw the setup in your mind, so we can talk about it?
  13. Replies
    43
    Views
    3,349

    Closed: Re: need 7pF to 10pF at 2.5GHz

    4-4.5 GHz (500MHz) not wide but not too narrow either.
  14. Replies
    43
    Views
    3,349

    Closed: Re: need 7pF to 10pF at 2.5GHz

    Reading these makes me sad about my job. How can I find people/material to help me learn about these stuff?

    I am currently suffering from a similar phenomeon on extracting the parasitic values of...
  15. Replies
    1
    Views
    294

    [SOLVED]Closed: DDS vs PLL RF Link Budget

    Hello all,

    I am wondering whats the difference between DDS generated chirp and PLL generated chirp's phase noise characteristics in Radar Link budget analysis? It seems many papers reference DDS...
  16. Replies
    8
    Views
    654

    [SOLVED]Closed: Re: Determining Switch Current

    Yeah you are correct, I should not be lazy about these stuff.
    However, things get messy in mind from time to time. Thinking about gigahertz level matching and transistors then going back to low...
  17. Replies
    8
    Views
    654

    [SOLVED]Closed: Re: Determining Switch Current

    Hmm, Square wave with aforementioned limits and
    I'm not sure with rise time since it will depend on PLL lock time as well.
  18. Replies
    8
    Views
    654

    [SOLVED]Closed: Re: Determining Switch Current

    Hello,

    I thought I said it in first post.

    100Hz or so is my switch rate, and +3.3 to -1 Volt is my Gate voltage.

    Maybe you mean something else?

    ktr
  19. Replies
    8
    Views
    654

    [SOLVED]Closed: Re: Determining Switch Current

    Hello,

    Although poorly drawn, this is what I mean. I am designing a multi-stage PA, and want to be able to control the current it draws by manipulating gate voltages.

    151250

    Kind Regards,
    ...
  20. Replies
    8
    Views
    654

    [SOLVED]Closed: Determining Switch Current

    Hello all,

    I have some basic questions regarding capacitor and switch behavior.

    Lets say Gate voltage of a transistor is 3.3V and I have bypass capacitors at the gate which makes 5uF in...
  21. [SOLVED]Closed: Re: Via Ground in ADS for connecting source of transistor to ground

    Ah, I used that transistor before. Nice for high power applications. Although, it have some stability issues, so be careful of that.

    You gotta simulate for different via dimaters along the...
  22. Replies
    8
    Views
    773

    [SOLVED]Closed: Re: X-Band Multiple Channel Config

    Yes, at first I thought I would put switch after PA, then I realized that switch can not handle 1-2 W power, so I decided to use it before PA, where line power is around 10mW. I will use a secondary...
  23. Replies
    8
    Views
    773

    [SOLVED]Closed: Re: X-Band Multiple Channel Config

    I found a switch which I thought good for me. https://www.analog.com/en/products/adrf5027.html this one(SPDT)151134

    I am thinking of giving a control voltage with duty cycle proportionate with...
  24. Replies
    1
    Views
    992

    Closed: Re: How to interpret EMC testing results?

    EMC test is required to determine that your device should have no effect on the other equipment around. Like placing a Transciever in a plane, where there are tens of other equipment around. You need...
  25. Closed: Re: Vivaldi antenna behave different with and without SMA connector in HFSS

    whats the definition of "behaving well" and "behaving badly" ?
Results 1 to 25 of 131
Page 1 of 6 1 2 3 4