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Simulators >> RF Simulators >> cmos down conversion mixer
https://designers-guide.org/forum/YaBB.pl?num=1202753208

Message started by udaykumarchintala on Feb 11^th, 2008, 10:06am

Title: cmos down conversion mixer
Post by udaykumarchintala on Feb 11^th, 2008, 10:06am

hii.
How to generate square wave of desired frequency in RF spectre for simulating the mixer????

Title: Re: cmos down conversion mixer
Post by Ken Kundert on Feb 11^th, 2008, 5:10pm

With a pulse source, just like you would in transient analysis.

-Ken

Title: Re: cmos down conversion mixer
Post by udaykumarchintala on Feb 12^th, 2008, 9:25am

hiii,
By using a pulse source I am unable to generate the required frequencies ,it is asking for a particular time period..............

Title: Re: cmos down conversion mixer
Post by didac on Feb 12^th, 2008, 9:52am

Hi,
Time-frequency duality. f=1/period,period=1/f
Hope it helps,

Title: Re: cmos down conversion mixer
Post by udaykumarchintala on Feb 14^th, 2008, 1:11am

Hi,
For example if I want to generate a 2.3 GHz LO square signal, can I generate it by giving a time period of
.434 n sec for the pulse source????????Will it work?????

Title: Re: cmos down conversion mixer
Post by Ken Kundert on Feb 14^th, 2008, 3:56pm

Set the period to 1/2.3GHz. The width and levels of the pulses can be adjusted with other parameters. See "spectre -h vsource" for more information.

-Ken

Title: Re: cmos down conversion mixer
Post by udaykumarchintala on Feb 26^th, 2008, 11:47am

Hi.....
How to calculate the extrapolation points while measuring the 1dB compression point and IIP3 for the mixer in spectre........

Thanks in advance.......

Title: Re: cmos down conversion mixer
Post by udaykumarchintala on Mar 3^rd, 2008, 9:24am

hi,
I have designed a mixer which has -1.477dBm 1dB compression point,but for the same I am unable to simulate the IIP3, RF frequncy is 2.4GHz and LO is 2.3GHz for this
mixer...please help......

Thanks in advance
uday

Title: Re: cmos down conversion mixer
Post by udaykumarchintala on Mar 3^rd, 2008, 12:15pm

Hi,
How to find out the LO-RF isolation in cadence spectre for a mixer?

Thanks in advance.......
uday

Title: Re: cmos down conversion mixer
Post by udaykumarchintala on Mar 4^th, 2008, 11:06am

Hi,
I have designed a mixer with RF =2.4GHz,LO=2.3GHz as we know the IF is at 100MHz.I got 1 dB compression point of -1.47dBm for this,but I am unable to calculate IIP3 for this in the spectre,I have taken the interfer as 2.41GHz ,for this the third order interferers at the output will be at 140MHz and at 90 MHz,while simulating I am unable to give the arry of indices in the PAC analysis in spectre......help me....

Thanks in advance......

Title: Re: cmos down conversion mixer
Post by khouly on Mar 24^th, 2008, 8:03am

to get the feed through , just plot the spectrum of the node u want , and then find the component and calculate how much attenuation

khouly

Title: Re: cmos down conversion mixer
Post by udaykumarchintala on Mar 25^th, 2008, 11:48pm

Hi,
expalin me a bit more......if i want to measure the feed through from LO-RF how should I do ?Should I use PSS analysis and plot spectrum at both LO
and RF ports and to see the feed through????

Title: Re: cmos down conversion mixer
Post by udaykumarchintala on Apr 11^th, 2008, 11:43am

hii,
For my mixer I have plotted voltage gain by PSS analysis and conversion gain by PSS/PXF .I am not getting the same value.whay?what is the difference?

Thanks

Title: Re: cmos down conversion mixer
Post by pancho_hideboo on Apr 13^th, 2008, 8:06am

udaykumarchintala wrote on Apr 11^th, 2008, 11:43am:

For my mixer I have plotted voltage gain by PSS analysis and conversion gain by PSS/PXF.
I am not getting the same value.whay?what is the difference?

Maybe you are using "Direct Plot Menu" to plot Gain. Is this correct ?
Do you understand gain definitions of PSS, PAC, PXF and Pnoise in "Direct Plot Menu".
See the followings.
http://www.designers-guide.org/Forum/YaBB.pl?num=1122952471/5#5
http://www.edaboard.com/viewtopic.php?t=214650&highlight=

You should write down gain definitions for PSS and PXF in "Direct Plot Menu".
Especially you have to study denominator of gain each for PSS and PXF.