[SI-LIST] Re: Via insertion loss
- From: Jory McKinley <jory_mckinley@xxxxxxxxx>
- To: "praveenkumardr@xxxxxxxxx" <praveenkumardr@xxxxxxxxx>, "si-list@xxxxxxxxxxxxx" <si-list@xxxxxxxxxxxxx>
- Date: Sat, 4 Aug 2012 12:08:14 -0700 (PDT)
Hello Paveen,
You are hitting quarter-wavelength in the setup you describe below @
approximately 5.9Ghz. Can you get your second port to where you made your
cut(s)? You can measure IL directly and will be able to see the resonances if
your LNA has enough bandwidth.
-Jory
From: Praveen Kumar <praveenkumardr@xxxxxxxxx>
To: si-list@xxxxxxxxxxxxx
Sent: Friday, August 3, 2012 3:17 PM
Subject: [SI-LIST] Via insertion loss
Hi all,
I'm trying to find via insertion loss in a RF path that has a antenna
connector on one end, followed by a trace (300 mils long) and then a via
and again trace that connects to LNA.
Now to find Via loss, all i'm doing is
first case : I measure S11 (path from Antenna-trace- via , cut the via
trace on the bottom) from Antenna to "after-via" (open end).
second case: I measure S11 (path from Antenna-trace on top just before it
connects via,) from Antenna to "before-via" (open end).
thus i get return loss in both scenarios, with via and without via. The
difference is return loss of via. half of this value is via insertion loss.
At 5 GHz I'm getting a value of 0.1 dB (actually little less than this)
loss and increases to 0.6 dB at 5.9 GHz.
I repeated this for all the Cores (All three available RF Paths (from
Antenna to Via) and got similar values.
The details are as follows here..
RF path length : approximately 350 mils
Number of layers : 8
thickness: 1.6mm (with tolerance)
via size: 20 mil pad - 10 mil drill (32 mil antipad).
dielectric :PER IPC-4101/94, /95, /125, /128, /130 OR /131 (HALOGEN-FREE
EPOXY-GLASS).
At the lower end of the frequency these values seem to be ok, but for
higher frequencies via loss seem to be way more than expected.
Do you feel the values are ok since it is at the extreme 5.9 GHz range only
that the via loss value is at its worst ?
please let me know if there is anything wrong with the method followed ?
Thank you,
Praveen
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxxxxxx 'unsubscribe' in the Subject field
or to administer your membership from a web page, go to:
//www.freelists.org/webpage/si-list
For help:
si-list-request@xxxxxxxxxxxxxxxxx 'help' in the Subject field
List forum is accessible at:
http://tech.groups.yahoo.com/group/si-list
List archives are viewable at:
//www.freelists.org/archives/si-list
Old (prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu
------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
or to administer your membership from a web page, go to:
//www.freelists.org/webpage/si-list
For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
List forum is accessible at:
http://tech.groups.yahoo.com/group/si-list
List archives are viewable at:
//www.freelists.org/archives/si-list
Old (prior to June 6, 2001) list archives are viewable at:
http://www.qsl.net/wb6tpu
Other related posts:
