mtt-11 : Messages : 1-29 of 29

Hello Igor,

In MultiCal and StatistiCAL you put in an estimate for the length of the fixture. The programs use this estimate at the lowest frequency to resolve this phase ambiguity. This is usually not difficult if the frequency is low enough. Then the programs use the solution at this lowest frequency and the length estimate to estimate the phase at the next frequency point, and so on. In this way, the programs step from frequency to frequency, each time estimating the phase at the next frequency point. The approach is not perfect, but it usually works in practice.

I hope that his is helpful,

Dylan

At 09:37 AM 7/30/2008, you wrote:

Thank you Dylan

When S21=S12 there is a 180deg ambiguity in the answer because of the
square root function. Similarly, there is a square root to solve for
S22 of the input adapter that gives another 180deg ambiguity.

The first 180deg ambiguity is ok because usually we need S12*S21
products and as long as the same 180deg error is made in calculating
both S-parameters of the input and the output adapters, the DUT
deembedding will be correct. However I'm not sure the 180deg ambiguity
in S22 of the input adapter is as easy to deal with.

BTW, I'd like to write a matlab routine to determine the full
S-parameters of the input and the output adapters.

Regards
Igor

>
> Sorry Igor,
>
> When de-embedding adapters you can use reciprocity
(S21=S12) to
> solve this problem. Both MultiCal and StatistiCAL allow you to solve
for
> adapter scattering parameters with multiline TRL, and that would be
a good
> place to start.
>
> Next time I will have to be more careful about getting the
reply
> to you!
>
> Best,
>
> Dylan
>
>
> At 03:54 PM 7/22/2008, you wrote:
>
> >Hello Dylan
> >
> >Looks like you replied to my message but the text did not show?
> >
> >Regards
> >Igor
> >
> >--- In < mailto:mtt-11%40yahoogroups.com>mtt-11@yahoogroups.com, Dylan
> >Williams <dylan@> wrote:
> > >
> > > At 07:46 AM 7/22/2008, you wrote:
> > >
> > > >Hello
> > > >
> > > >I've been following Doug Rytting presentation called "TRL
> > > >Calibration". The equations all make sense and give good results
> > > >however the presentation does not seem complete as it does not
discuss
> > > >how to do the final step of separating e10e32 and e23e01 terms
(these
> > > >terms are the S12's and S21's of the two error adapters).
> > > >
> > > >Can anybody help me with this? I'd like to determine the
S-parameters
> > > >of the two error adapters.
> > > >
> > > >Thank you
> > > >Igor
> > > >
> > > >
> > >
> > >
> > >
> > > -----------------------------------------------------
> > > Dylan Williams <dylan@>
> > > NIST 818.01 <dylan@>
> > > 325 Broadway [+1] (303)497-3138 (TEL)
> > > Boulder CO 80305 USA [+1] (303)497-3970 (FAX)
> > >
< http://www.boulder.nist.gov/dylan/ > http://www.boulder.nist.gov/dylan/
> > > -----------------------------------------------------
> > >
> >
> >
>
>
>
> -----------------------------------------------------
> Dylan Williams <dylan@...>
> NIST 818.01 <dylan@...>
> 325 Broadway [+1] (303)497-3138 (TEL)
> Boulder CO 80305 USA [+1] (303)497-3970 (FAX)
> http://www.boulder.nist.gov/dylan/
> -----------------------------------------------------
>

-----------------------------------------------------
Dylan Williams               <dylan@...>
NIST 818.01                  <dylan@...>
325 Broadway                 [+1] (303)497-3138 (TEL)
Boulder CO 80305 USA         [+1] (303)497-3970 (FAX)
http://www.boulder.nist.gov/dylan/
-----------------------------------------------------

#28

From: "igorlinetsky" <igor_linetsky@...>
Date: Wed Jul 30, 2008 5:56 pm
Subject: Re: TRL self-calibration algorithm

igorlinetsky

Offline

Actually knowing the type of the reflect standard corrects the S22 phase.

Igor

--- In mtt-11@yahoogroups.com, "igorlinetsky" <igor_linetsky@...> wrote:
>
> Thank you Dylan
>
> When S21=S12 there is a 180deg ambiguity in the answer because of the
> square root function.  Similarly, there is a square root to solve for
> S22 of the input adapter that gives another 180deg ambiguity.
>
> The first 180deg ambiguity is ok because usually we need S12*S21
> products and as long as the same 180deg error is made in calculating
> both S-parameters of the input and the output adapters, the DUT
> deembedding will be correct. However I'm not sure the 180deg ambiguity
> in S22 of the input adapter is as easy to deal with.
>
> BTW, I'd like to write a matlab routine to determine the full
> S-parameters of the input and the output adapters.
>
> Regards
> Igor
>
> >
> > Sorry Igor,
> >
> >          When de-embedding adapters you can use reciprocity
> (S21=S12) to
> > solve this problem. Both MultiCal and StatistiCAL allow you to solve
> for
> > adapter scattering parameters with multiline TRL, and that would be
> a good
> > place to start.
> >
> >          Next time I will have to be more careful about getting the
> reply
> > to you!
> >
> > Best,
> >
> > Dylan
> >
> >
> > At 03:54 PM 7/22/2008, you wrote:
> >
> > >Hello Dylan
> > >
> > >Looks like you replied to my message but the text did not show?
> > >
> > >Regards
> > >Igor
> > >
> > >--- In <mailto:mtt-11%40yahoogroups.com>mtt-11@yahoogroups.com,
Dylan
> > >Williams <dylan@> wrote:
> > > >
> > > > At 07:46 AM 7/22/2008, you wrote:
> > > >
> > > > >Hello
> > > > >
> > > > >I've been following Doug Rytting presentation called "TRL
> > > > >Calibration". The equations all make sense and give good results
> > > > >however the presentation does not seem complete as it does not
> discuss
> > > > >how to do the final step of separating e10e32 and e23e01 terms
> (these
> > > > >terms are the S12's and S21's of the two error adapters).
> > > > >
> > > > >Can anybody help me with this? I'd like to determine the
> S-parameters
> > > > >of the two error adapters.
> > > > >
> > > > >Thank you
> > > > >Igor
> > > > >
> > > > >
> > > >
> > > >
> > > >
> > > > -----------------------------------------------------
> > > > Dylan Williams <dylan@>
> > > > NIST 818.01 <dylan@>
> > > > 325 Broadway [+1] (303)497-3138 (TEL)
> > > > Boulder CO 80305 USA [+1] (303)497-3970 (FAX)
> > > >
> <http://www.boulder.nist.gov/dylan/>http://www.boulder.nist.gov/dylan/
> > > > -----------------------------------------------------
> > > >
> > >
> > >
> >
> >
> >
> > -----------------------------------------------------
> > Dylan Williams               <dylan@>
> > NIST 818.01                  <dylan@>
> > 325 Broadway                 [+1] (303)497-3138 (TEL)
> > Boulder CO 80305 USA         [+1] (303)497-3970 (FAX)
> > http://www.boulder.nist.gov/dylan/
> > -----------------------------------------------------
> >
>

#27

From: "igorlinetsky" <igor_linetsky@...>
Date: Wed Jul 30, 2008 3:37 pm
Subject: Re: TRL self-calibration algorithm

igorlinetsky

Offline

Thank you Dylan

When S21=S12 there is a 180deg ambiguity in the answer because of the
square root function.  Similarly, there is a square root to solve for
S22 of the input adapter that gives another 180deg ambiguity.

The first 180deg ambiguity is ok because usually we need S12*S21
products and as long as the same 180deg error is made in calculating
both S-parameters of the input and the output adapters, the DUT
deembedding will be correct. However I'm not sure the 180deg ambiguity
in S22 of the input adapter is as easy to deal with.

BTW, I'd like to write a matlab routine to determine the full
S-parameters of the input and the output adapters.

Regards
Igor

>
> Sorry Igor,
>
>          When de-embedding adapters you can use reciprocity
(S21=S12) to
> solve this problem. Both MultiCal and StatistiCAL allow you to solve
for
> adapter scattering parameters with multiline TRL, and that would be
a good
> place to start.
>
>          Next time I will have to be more careful about getting the
reply
> to you!
>
> Best,
>
> Dylan
>
>
> At 03:54 PM 7/22/2008, you wrote:
>
> >Hello Dylan
> >
> >Looks like you replied to my message but the text did not show?
> >
> >Regards
> >Igor
> >
> >--- In <mailto:mtt-11%40yahoogroups.com>mtt-11@yahoogroups.com, Dylan
> >Williams <dylan@> wrote:
> > >
> > > At 07:46 AM 7/22/2008, you wrote:
> > >
> > > >Hello
> > > >
> > > >I've been following Doug Rytting presentation called "TRL
> > > >Calibration". The equations all make sense and give good results
> > > >however the presentation does not seem complete as it does not
discuss
> > > >how to do the final step of separating e10e32 and e23e01 terms
(these
> > > >terms are the S12's and S21's of the two error adapters).
> > > >
> > > >Can anybody help me with this? I'd like to determine the
S-parameters
> > > >of the two error adapters.
> > > >
> > > >Thank you
> > > >Igor
> > > >
> > > >
> > >
> > >
> > >
> > > -----------------------------------------------------
> > > Dylan Williams <dylan@>
> > > NIST 818.01 <dylan@>
> > > 325 Broadway [+1] (303)497-3138 (TEL)
> > > Boulder CO 80305 USA [+1] (303)497-3970 (FAX)
> > >
<http://www.boulder.nist.gov/dylan/>http://www.boulder.nist.gov/dylan/
> > > -----------------------------------------------------
> > >
> >
> >
>
>
>
> -----------------------------------------------------
> Dylan Williams               <dylan@...>
> NIST 818.01                  <dylan@...>
> 325 Broadway                 [+1] (303)497-3138 (TEL)
> Boulder CO 80305 USA         [+1] (303)497-3970 (FAX)
> http://www.boulder.nist.gov/dylan/
> -----------------------------------------------------
>

#26

From: Dylan Williams <dylan@...>
Date: Wed Jul 23, 2008 12:56 am
Subject: Re: Re: TRL self-calibration algorithm

dylanmtt

Offline

Sorry Igor,

When de-embedding adapters you can use reciprocity (S21=S12) to solve this problem. Both MultiCal and StatistiCAL allow you to solve for adapter scattering parameters with multiline TRL, and that would be a good place to start.

Next time I will have to be more careful about getting the reply to you!

Best,

Dylan

At 03:54 PM 7/22/2008, you wrote:

Hello Dylan

Looks like you replied to my message but the text did not show?

Regards
Igor

--- In mtt-11@yahoogroups.com, Dylan Williams <dylan@...> wrote:
>
> At 07:46 AM 7/22/2008, you wrote:
>
> >Hello
> >
> >I've been following Doug Rytting presentation called "TRL
> >Calibration". The equations all make sense and give good results
> >however the presentation does not seem complete as it does not discuss
> >how to do the final step of separating e10e32 and e23e01 terms (these
> >terms are the S12's and S21's of the two error adapters).
> >
> >Can anybody help me with this? I'd like to determine the S-parameters
> >of the two error adapters.
> >
> >Thank you
> >Igor
> >
> >
>
>
>
> -----------------------------------------------------
> Dylan Williams <dylan@...>
> NIST 818.01 <dylan@...>
> 325 Broadway [+1] (303)497-3138 (TEL)
> Boulder CO 80305 USA [+1] (303)497-3970 (FAX)
> http://www.boulder.nist.gov/dylan/
> -----------------------------------------------------
>

#25

From: "igorlinetsky" <igor_linetsky@...>
Date: Tue Jul 22, 2008 9:54 pm
Subject: Re: TRL self-calibration algorithm

igorlinetsky

Offline

Hello Dylan

Looks like you replied to my message but the text did not show?

Regards
Igor

--- In mtt-11@yahoogroups.com, Dylan Williams <dylan@...> wrote:
>
> At 07:46 AM 7/22/2008, you wrote:
>
> >Hello
> >
> >I've been following Doug Rytting presentation called "TRL
> >Calibration". The equations all make sense and give good results
> >however the presentation does not seem complete as it does not discuss
> >how to do the final step of separating e10e32 and e23e01 terms (these
> >terms are the S12's and S21's of the two error adapters).
> >
> >Can anybody help me with this? I'd like to determine the S-parameters
> >of the two error adapters.
> >
> >Thank you
> >Igor
> >
> >
>
>
>
> -----------------------------------------------------
> Dylan Williams               <dylan@...>
> NIST 818.01                  <dylan@...>
> 325 Broadway                 [+1] (303)497-3138 (TEL)
> Boulder CO 80305 USA         [+1] (303)497-3970 (FAX)
> http://www.boulder.nist.gov/dylan/
> -----------------------------------------------------
>

#24

From: Dylan Williams <dylan@...>
Date: Tue Jul 22, 2008 7:07 pm
Subject: Re: TRL self-calibration algorithm

dylanmtt

Offline

At 07:46 AM 7/22/2008, you wrote:

Hello

I've been following Doug Rytting presentation called "TRL
Calibration". The equations all make sense and give good results
however the presentation does not seem complete as it does not discuss
how to do the final step of separating e10e32 and e23e01 terms (these
terms are the S12's and S21's of the two error adapters).

Can anybody help me with this? I'd like to determine the S-parameters
of the two error adapters.

Thank you
Igor

#23

From: "igorlinetsky" <igor_linetsky@...>
Date: Tue Jul 22, 2008 1:46 pm
Subject: TRL self-calibration algorithm

igorlinetsky

Offline

Hello

I've been following Doug Rytting presentation called "TRL
Calibration".  The equations all make sense and give good results
however the presentation does not seem complete as it does not discuss
how to do the final step of separating e10e32 and e23e01 terms (these
terms are the S12's and S21's of the two error adapters).

Can anybody help me with this?  I'd like to determine the S-parameters
of the two error adapters.

Thank you
Igor

#22

From: Dylan Williams <dylan@...>
Date: Tue Feb 26, 2008 4:27 am
Subject: Re: Re: What is the Most Practical Method to Add Optical Capabilities to an 8510C?

dylanmtt

Offline

Hello Fei,

It still is very difficult to measure scattering parameters with non-contact means. Nevertheless you might find this paper our group wrote on the subject interesting.

D.F. Williams, P.D. Hale, T.S. Clement, and J.M. Morgan, "Calibrated 200 GHz Waveform Measurement," IEEE Trans. Microwave Theory and Tech ., vol. 53, no. 4, pp. 1384-1389, April, 2005.

Dylan

At 08:03 AM 2/25/2008, you wrote:

Are you guys talking about the contactless probing solution? Sorry
about that if not.

A few years back, I heard that people used optoelectronic probe to do
[S] measurements without mechanical contacts? Is it getting more and
more practical and feasible?

Thanks
Fei
--- In mtt-11@yahoogroups.com, Dylan Williams <dylan@...> wrote:
>
> Hello Cory,
>
> If you are interested in power calibrations, I think that
Agilent,
> New Focus, Newport, U2t, perhaps other options exist. Some of these
might
> have phase calibrations as well, probably measured with an
oscilloscope.
>
> For magnitude and phase calibrations with mismatch
corrections
> traceable to electro-optic sampling, as far as I know, only NIST
and
> Anritsu have anything to offer. Our calibrations are quite
difficult and
> time consuming, so I think that Anritsu might be a better choice
for you.
>
> I hope that is helpful,
>
> Dylan
>
> At 01:01 PM 7/31/2007, you wrote:
>
>
> >Dylan,
> >
> >I contacted Anritsu, and they only support 1550nm for now, and
their list
> >price is about 25K. Do you know of any other vendors that are
selling
> >calibrated photodiodes (I think Agilent is only selling full
systems)? Can
> >you give me an order of magnitude estimate as to how much would it
cost
> >from NIST?
> >
> >Thanks,
> >Cory
> >
> >Dylan Williams
> ><< mailto:dylan%40boulder.ni>dylan@...
> >st.gov> To
> >Sent by: < mailto:mtt-11%40yahoogroups.com>mtt-11@yahoogroups.com
> >mtt-11@yahoogroup cc
> >s.com
> >Subject
> >Re: [mtt-11] What is the Most
> >07/31/2007 07:38 Practical Method to Add Optical
> >AM Capabilities to an 8510C?
> >
> >
> >Please respond to
> >mtt-11@yahoogroup
> >s.com
> >
> >
> >
> >Hello Cory,
> >
> >I believe that you are correct that the most inexpensive way to
> >proceed is to use a calibrated photodiode. I am not sure how much
Anritsu
> >sells their calibrated photodiodes for, but I would imagine that
would be
> >less expensive than purchasing a photodiode and calibration
directly from
> >NIST.
> >
> >Dylan
> >
> >At 07:25 PM 7/30/2007, you wrote:
> >
> >Hi,
> >
> >I am looking into what is the most practical method to add optical
> >capabilities to my 8510C. I need to be able to measure
communication
> >laser diodes and photodiodes over the wavelength range of 850nm to
> >1550nm (from 1Gbps to 10Gbps). I don't have the budget to purchase
> >an off the shelf lightwave component analyzer (especially since I
> >probably need more than one to cover this range), so I am looking
> >into adding calibrated laser sources and detectors to my existing
> >VNA. From what I gather the biggest challenge is to calibrate the
> >detector, and then that can be used to calibrate the source.
> >
> >I see many papers regarding calibrating photodetectors, but this
> >seems to be fairly involved. Is this the only practical option, or
> >does anyone sell reasonably priced calibrated photodetectors? So
> >far, I have only seen a single wavelength model by Anritsu.
> >
> >For the light source, is there anything good that is commercially
> >available, or am I best off building something myself. For home
> >built, is it better to directly modulate or use and external
> >modulator?
> >
> >Any feedback is appreciated.
> >
> >Thanks,
> >Cory
> >
> >-----------------------------------------------------
> >Dylan Williams << mailto:dylan%40boulder.nist.gov>dylan@...>
> >NIST 818.01 << mailto:dylan%40ieee.org>dylan@...>
> >325 Broadway [+1] (303)497-3138 (TEL)
> >Boulder CO 80305 USA [+1] (303)497-3970 (FAX)
>
>< http://www.boulder.nist.gov/dylan/ > http://www.boulder.nist.gov/dylan
/
> >-----------------------------------------------------
> >
> >
>
>
>
> -----------------------------------------------------
> Dylan Williams <dylan@...>
> NIST 818.01 <dylan@...>
> 325 Broadway [+1] (303)497-3138 (TEL)
> Boulder CO 80305 USA [+1] (303)497-3970 (FAX)
> http://www.boulder.nist.gov/dylan/
> -----------------------------------------------------
>

-----------------------------------------------------
Dylan Williams               <dylan@...>
NIST 818.01                  <dylan@...>
325 Broadway                 [+1] (303)497-3138 (TEL)
Boulder CO 80305 USA         [+1] (303)497-3970 (FAX)
http://www.boulder.nist.gov/dylan/
-----------------------------------------------------

#21

From: "feicaguo" <feicaguo@...>
Date: Mon Feb 25, 2008 3:03 pm
Subject: Re: What is the Most Practical Method to Add Optical Capabilities to an 8510C?

feicaguo

Offline

Are you guys talking about the contactless probing solution?  Sorry
about that if not.

A few years back, I heard that people used optoelectronic probe to do
[S] measurements without mechanical contacts?  Is it getting more and
more practical and feasible?

Thanks
Fei
--- In mtt-11@yahoogroups.com, Dylan Williams <dylan@...> wrote:
>
> Hello Cory,
>
>          If you are interested in power calibrations, I think that
Agilent,
> New Focus, Newport, U2t, perhaps other options exist. Some of these
might
> have phase calibrations as well, probably measured with an
oscilloscope.
>
>          For magnitude and phase calibrations with mismatch
corrections
> traceable to electro-optic sampling, as far as I know, only NIST
and
> Anritsu have anything to offer. Our calibrations are quite
difficult and
> time consuming, so I think that Anritsu might be a better choice
for you.
>
> I hope that is helpful,
>
> Dylan
>
> At 01:01 PM 7/31/2007, you wrote:
>
>
> >Dylan,
> >
> >I contacted Anritsu, and they only support 1550nm for now, and
their list
> >price is about 25K. Do you know of any other vendors that are
selling
> >calibrated photodiodes (I think Agilent is only selling full
systems)? Can
> >you give me an order of magnitude estimate as to how much would it
cost
> >from NIST?
> >
> >Thanks,
> >Cory
> >
> >Dylan Williams
> ><<mailto:dylan%40boulder.ni>dylan@...
> >st.gov> To
> >Sent by: <mailto:mtt-11%40yahoogroups.com>mtt-11@yahoogroups.com
> >mtt-11@yahoogroup cc
> >s.com
> >Subject
> >Re: [mtt-11] What is the Most
> >07/31/2007 07:38 Practical Method to Add Optical
> >AM Capabilities to an 8510C?
> >
> >
> >Please respond to
> >mtt-11@yahoogroup
> >s.com
> >
> >
> >
> >Hello Cory,
> >
> >I believe that you are correct that the most inexpensive way to
> >proceed is to use a calibrated photodiode. I am not sure how much
Anritsu
> >sells their calibrated photodiodes for, but I would imagine that
would be
> >less expensive than purchasing a photodiode and calibration
directly from
> >NIST.
> >
> >Dylan
> >
> >At 07:25 PM 7/30/2007, you wrote:
> >
> >Hi,
> >
> >I am looking into what is the most practical method to add optical
> >capabilities to my 8510C. I need to be able to measure
communication
> >laser diodes and photodiodes over the wavelength range of 850nm to
> >1550nm (from 1Gbps to 10Gbps). I don't have the budget to purchase
> >an off the shelf lightwave component analyzer (especially since I
> >probably need more than one to cover this range), so I am looking
> >into adding calibrated laser sources and detectors to my existing
> >VNA. From what I gather the biggest challenge is to calibrate the
> >detector, and then that can be used to calibrate the source.
> >
> >I see many papers regarding calibrating photodetectors, but this
> >seems to be fairly involved. Is this the only practical option, or
> >does anyone sell reasonably priced calibrated photodetectors? So
> >far, I have only seen a single wavelength model by Anritsu.
> >
> >For the light source, is there anything good that is commercially
> >available, or am I best off building something myself. For home
> >built, is it better to directly modulate or use and external
> >modulator?
> >
> >Any feedback is appreciated.
> >
> >Thanks,
> >Cory
> >
> >-----------------------------------------------------
> >Dylan Williams <<mailto:dylan%40boulder.nist.gov>dylan@...>
> >NIST 818.01 <<mailto:dylan%40ieee.org>dylan@...>
> >325 Broadway [+1] (303)497-3138 (TEL)
> >Boulder CO 80305 USA [+1] (303)497-3970 (FAX)
>
><http://www.boulder.nist.gov/dylan/>http://www.boulder.nist.gov/dylan
/
> >-----------------------------------------------------
> >
> >
>
>
>
> -----------------------------------------------------
> Dylan Williams               <dylan@...>
> NIST 818.01                  <dylan@...>
> 325 Broadway                 [+1] (303)497-3138 (TEL)
> Boulder CO 80305 USA         [+1] (303)497-3970 (FAX)
> http://www.boulder.nist.gov/dylan/
> -----------------------------------------------------
>

#20

From: Dylan Williams <dylan@...>
Date: Tue Jul 31, 2007 10:04 pm
Subject: Re: What is the Most Practical Method to Add Optical Capabilities to an 8510C?

dylanmtt

Offline

Hello Cory,

If you are interested in power calibrations, I think that Agilent, New Focus, Newport, U2t, perhaps other options exist. Some of these might have phase calibrations as well, probably measured with an oscilloscope.

For magnitude and phase calibrations with mismatch corrections traceable to electro-optic sampling, as far as I know, only NIST and Anritsu have anything to offer. Our calibrations are quite difficult and time consuming, so I think that Anritsu might be a better choice for you.

I hope that is helpful,

Dylan

At 01:01 PM 7/31/2007, you wrote:

Dylan,

I contacted Anritsu, and they only support 1550nm for now, and their list
price is about 25K. Do you know of any other vendors that are selling
calibrated photodiodes (I think Agilent is only selling full systems)? Can
you give me an order of magnitude estimate as to how much would it cost
from NIST?

Thanks,
Cory

Dylan Williams
<dylan@...
st.gov> To
Sent by: mtt-11@yahoogroups.com
mtt-11@yahoogroup cc
s.com
Subject
Re: [mtt-11] What is the Most
07/31/2007 07:38 Practical Method to Add Optical
AM Capabilities to an 8510C?

Please respond to
mtt-11@yahoogroup
s.com

Hello Cory,

I believe that you are correct that the most inexpensive way to
proceed is to use a calibrated photodiode. I am not sure how much Anritsu
sells their calibrated photodiodes for, but I would imagine that would be
less expensive than purchasing a photodiode and calibration directly from
NIST.

Dylan

At 07:25 PM 7/30/2007, you wrote:

Hi,

I am looking into what is the most practical method to add optical
capabilities to my 8510C. I need to be able to measure communication
laser diodes and photodiodes over the wavelength range of 850nm to
1550nm (from 1Gbps to 10Gbps). I don't have the budget to purchase
an off the shelf lightwave component analyzer (especially since I
probably need more than one to cover this range), so I am looking
into adding calibrated laser sources and detectors to my existing
VNA. From what I gather the biggest challenge is to calibrate the
detector, and then that can be used to calibrate the source.

I see many papers regarding calibrating photodetectors, but this
seems to be fairly involved. Is this the only practical option, or
does anyone sell reasonably priced calibrated photodetectors? So
far, I have only seen a single wavelength model by Anritsu.

For the light source, is there anything good that is commercially
available, or am I best off building something myself. For home
built, is it better to directly modulate or use and external
modulator?

Any feedback is appreciated.

Thanks,
Cory

-----------------------------------------------------
Dylan Williams <dylan@... >
NIST 818.01 <dylan@...>
325 Broadway [+1] (303)497-3138 (TEL)
Boulder CO 80305 USA [+1] (303)497-3970 (FAX)
http://www.boulder.nist.gov/dylan/
-----------------------------------------------------

#19

From: cory.compton@...
Date: Tue Jul 31, 2007 7:01 pm
Subject: Re: What is the Most Practical Method to Add Optical Capabilities to an 8510C?

comptoca

Offline

Dylan,

I contacted Anritsu, and they only support 1550nm for now, and their list
price is about 25K.  Do you know of any other vendors that are selling
calibrated photodiodes (I think Agilent is only selling full systems)?  Can
you give me an order of magnitude estimate as to how much would it cost
from NIST?

Thanks,
Cory




              Dylan Williams
              <dylan@...
              st.gov>                                                    To
              Sent by:                  mtt-11@yahoogroups.com
              mtt-11@yahoogroup                                          cc
              s.com
                                                                    Subject
                                        Re: [mtt-11] What is the Most
              07/31/2007 07:38          Practical Method to Add Optical
              AM                        Capabilities to an 8510C?


              Please respond to
              mtt-11@yahoogroup
                    s.com






Hello Cory,

         I believe that you are correct that the most inexpensive way to
proceed is to use a calibrated photodiode. I am not sure how much Anritsu
sells their calibrated photodiodes for, but I would imagine that would be
less expensive than purchasing a photodiode and calibration directly from
NIST.

Dylan

At 07:25 PM 7/30/2007, you wrote:

       Hi,

       I am looking into what is the most practical method to add optical
       capabilities to my 8510C. I need to be able to measure communication
       laser diodes and photodiodes over the wavelength range of 850nm to
       1550nm (from 1Gbps to 10Gbps). I don't have the budget to purchase
       an off the shelf lightwave component analyzer (especially since I
       probably need more than one to cover this range), so I am looking
       into adding calibrated laser sources and detectors to my existing
       VNA. From what I gather the biggest challenge is to calibrate the
       detector, and then that can be used to calibrate the source.

       I see many papers regarding calibrating photodetectors, but this
       seems to be fairly involved. Is this the only practical option, or
       does anyone sell reasonably priced calibrated photodetectors? So
       far, I have only seen a single wavelength model by Anritsu.

       For the light source, is there anything good that is commercially
       available, or am I best off building something myself. For home
       built, is it better to directly modulate or use and external
       modulator?

       Any feedback is appreciated.

       Thanks,
       Cory





-----------------------------------------------------
Dylan Williams               <dylan@...>
NIST 818.01                  <dylan@...>
325 Broadway                 [+1] (303)497-3138 (TEL)
Boulder CO 80305 USA         [+1] (303)497-3970 (FAX)
http://www.boulder.nist.gov/dylan/
-----------------------------------------------------

#18

From: Dylan Williams <dylan@...>
Date: Tue Jul 31, 2007 2:38 pm
Subject: Re: What is the Most Practical Method to Add Optical Capabilities to an 8510C?

dylanmtt

Offline

Hello Cory,

I believe that you are correct that the most inexpensive way to proceed is to use a calibrated photodiode. I am not sure how much Anritsu sells their calibrated photodiodes for, but I would imagine that would be less expensive than purchasing a photodiode and calibration directly from NIST.

Dylan

At 07:25 PM 7/30/2007, you wrote:

Hi,

I am looking into what is the most practical method to add optical
capabilities to my 8510C. I need to be able to measure communication
laser diodes and photodiodes over the wavelength range of 850nm to
1550nm (from 1Gbps to 10Gbps). I don't have the budget to purchase
an off the shelf lightwave component analyzer (especially since I
probably need more than one to cover this range), so I am looking
into adding calibrated laser sources and detectors to my existing
VNA. From what I gather the biggest challenge is to calibrate the
detector, and then that can be used to calibrate the source.

I see many papers regarding calibrating photodetectors, but this
seems to be fairly involved. Is this the only practical option, or
does anyone sell reasonably priced calibrated photodetectors? So
far, I have only seen a single wavelength model by Anritsu.

For the light source, is there anything good that is commercially
available, or am I best off building something myself. For home
built, is it better to directly modulate or use and external
modulator?

Any feedback is appreciated.

Thanks,
Cory

#17

From: "comptoca" <cory.compton@...>
Date: Tue Jul 31, 2007 1:25 am
Subject: What is the Most Practical Method to Add Optical Capabilities to an 8510C?

comptoca

Offline

Hi,

I am looking into what is the most practical method to add optical
capabilities to my 8510C.  I need to be able to measure communication
laser diodes and photodiodes over the wavelength range of 850nm to
1550nm (from 1Gbps to 10Gbps).  I don't have the budget to purchase
an off the shelf lightwave component analyzer (especially since I
probably need more than one to cover this range), so I am looking
into adding calibrated laser sources and detectors to my existing
VNA.  From what I gather the biggest challenge is to calibrate the
detector, and then that can be used to calibrate the source.

I see many papers regarding calibrating photodetectors, but this
seems to be fairly involved.  Is this the only practical option, or
does anyone sell reasonably priced calibrated photodetectors?  So
far, I have only seen a single wavelength model by Anritsu.

For the light source, is there anything good that is commercially
available, or am I best off building something myself.  For home
built, is it better to directly modulate or use and external
modulator?

Any feedback is appreciated.

Thanks,
Cory

#16

From: Dylan Williams <dylan@...>
Date: Thu Mar 15, 2007 5:10 pm
Subject: Re: Laser Diode (TOSA) Measurment Fixture

dylanmtt

Offline

Dear Cory,

In my experience, on-wafer probes can be made to work quite nicely with TRL standards printed on PCB. I would consider establishing your first-tier electrical reference plane right in a microstrip line on the PCB. This will allow you to connect your TO can directly to the PCB in the same way you do in production, and determine its parasitics in the environment you intend to use it in. The best way to do this generally is to use the same transmission line in your TRL calibration as you use to connect to the TO can in your circuit, if that is possible.

Good luck,

Dylan

At 07:42 PM 2/14/2007, you wrote:

Hi,

I am trying to measure and model a comunication laser diode (TOSA) in
a TO can. In this case it is a 1550nm wavelength DFB laser intended
for 2.5Gbps. It will be used with a dual-loop laser driver, and we
are primarily interested in the monitor photodiode response rather
than the optical response.

Since I don't have an optical VNA, I am just doing electrical
measurements from the laser diode input to the photodiode output with
a standard 2-port VNA (8510C or 8753E). The TOSA has three
terminals: laser cathode, photodiode anode, common laser anode and
photodiode cathode. I am currently using a homemade fixture composed
of two SMA PCB connectors soldered end to end, with the center pins
shortened to allow the insertion of the TOSA. I am doing a coaxial
adapter removal calibration on the VNA, and I have created additional
fixtures in open, short, and thru configurations in order to develop
a model for the fixture.

I am having a couple of issues with this approach. First, the TOSA
is normally mounted on the edge of a PCB, with the laser and common
nodes connected on top of the PCB and the photodiode node connected
to the bottom of the PCB. This is obviously a different environment
than my fixture, so there will be some discrepancy. Second, in order
to connect the common lead I either have to bend the lead to reach
the fixture or add a short piece of wire. The inductance in the
ground lead significantly affects the results of the coupling between
input and output.

I am interested in obtaining a better fixture, but I don't know if
there is something commercially availible that would work well in
this situation. My other option is to design a PCB fixture myself
(with help from our PCB group). Please let me know if you have any
suggestions or comments.

Thanks,
Cory

#15

From: "comptoca" <cory.compton@...>
Date: Thu Feb 15, 2007 1:42 am
Subject: Laser Diode (TOSA) Measurment Fixture

comptoca

Offline

Hi,

I am trying to measure and model a comunication laser diode (TOSA) in
a TO can.  In this case it is a 1550nm wavelength DFB laser intended
for 2.5Gbps.  It will be used with a dual-loop laser driver, and we
are primarily interested in the monitor photodiode response rather
than the optical response.

Since I don't have an optical VNA, I am just doing electrical
measurements from the laser diode input to the photodiode output with
a standard 2-port VNA (8510C or 8753E).  The TOSA has three
terminals: laser cathode, photodiode anode, common laser anode and
photodiode cathode.  I am currently using a homemade fixture composed
of two SMA PCB connectors soldered end to end, with the center pins
shortened to allow the insertion of the TOSA.  I am doing a coaxial
adapter removal calibration on the VNA, and I have created additional
fixtures in open, short, and thru configurations in order to develop
a model for the fixture.

I am having a couple of issues with this approach.  First, the TOSA
is normally mounted on the edge of a PCB, with the laser and common
nodes connected on top of the PCB and the photodiode node connected
to the bottom of the PCB.  This is obviously a different environment
than my fixture, so there will be some discrepancy.  Second, in order
to connect the common lead I either have to bend the lead to reach
the fixture or add a short piece of wire.  The inductance in the
ground lead significantly affects the results of the coupling between
input and output.

I am interested in obtaining a better fixture, but I don't know if
there is something commercially availible that would work well in
this situation.  My other option is to design a PCB fixture myself
(with help from our PCB group).  Please let me know if you have any
suggestions or comments.

Thanks,
Cory

#14

From: "rolandgesche" <roland.gesche@...>
Date: Thu Jul 20, 2006 7:03 am
Subject: XML measurement data files

rolandgesche

Offline

Hallo,

we are storing our measured data, e. g. s-parameters from the VNA,
transistor parameter sets, load-pull data, intermodulatioon data, etc.
in ASCII-Files, formated in Touchstone or MDIF.

We think it would be a good idea to change to XML-formats to make it
easier to import data in external software products like EXCEL and we
could write our own software faster using XML-tools for parsing.

But it makes not so much sense to define out own syntax. We woulkd
prefer to have a standard with naming and structure conventions for
microwave measurement data. Then data and application would be
portable and exchangable. We asked Agilent and R&S which might be the
ones to set standards like this, but there seems no much activity yet.

Does anybody in this group know about such activities?

Regards
Roland Gesche

#13

From: faisal jamil <faisal_burak@...>
Date: Sat Oct 15, 2005 1:28 pm
Subject: Matched Filters

faisal_burak

Offline

Hello,

I need some help about implementation of matched
filters, or correlators, in Lab View. I am new in Lab
view and know only its basics. I need to develop
matched filters for a qpsk receiver, in Lab view. I am
receiving a signal of 600 KHz, and 1.5 volts, having
data on it.

I've Lab view 6.2 installed on my system, I'll be
thank ful if anybody guides me about which VI to use,
for matched filters, Or if there is some example
already present.

Best Regards,
/Faisal.



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#12

From: "ezz_zheng" <ezz_zheng@...>
Date: Sat Jul 16, 2005 9:29 pm
Subject: 4 port calibration

ezz_zheng

Offline

Hi

This will be my first time to perform 4 port measurement with PNA.
Could you let me know what is the best way to perform 4-port
calibration with both SOLT and TRL measurement?

Thanks,
Emily

#11

From: Dylan Williams <dylan@...>
Date: Tue Feb 8, 2005 4:44 pm
Subject: Re:

dylanmtt

Offline

In general, we only use NISTCal for 4-port calibrations. If you are
performing 2-port calibrations, you would better off using MultiCal or
StatistiCAL. Here are some partial answers to your questions.

At 11:09 AM 2/1/2005 +0200, you wrote:

>I would like to know if you have software available to load the 12-term
>VNA calibration coefficients from statistiCAL into the HP8510 VNA.

Sorry, but I do not have such software.


>
>
>In NISTcal, I am unable to click the "DEEMBED AND SAVE 2-PORT PARAMETERS"
>button. The "devices in this directory" indicator does not switch on.

The device directory must be filled with device measurements taken by
NISTCal before this button will light up. That is a possible problem.

>I am not sure in what format file the device must be, but is currently
>named dut.s2p. In the "calibrate 2-port" menu there is another indicator
>between the thru and reflect indicators called the "Switching Terms File".
>The text-box is hidden on my PC (windows XP) and I am not sure what to
>enter there. I think that I understand the rest of the program. It would
>be nice to have a test example.

You need switch terms for a first-tier calibration, but not for a
second-tier calibration. So perhaps that is the problem. Usually we
automatically save the switch terms in a file "GXXX" where XXX is the name
of the thru measurement, but we only do that for first-tier calibrations.


>
>
>Is there a publication available on the optimum number of lines for a
>multiline trl calibration or the effect of using more lines. On page 1212
>of IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 39, NO. 7,
>JULY 1991, A Multiline Method of Network Analyzer Calibration, Roger B.
>Marks, Member, IEEE it states:
>
>Although we have no proof, an
>
>optimal design seems to require one line to be a quarter
>
>wavelength long at the band center and the other line to
>
>be three times that length .
>
>Has further research been done in this field and is there a rule of thumb?

No, little research has been done. But the program FINDLEN will allow you
to design these calibration sets.


>
>
>Thank you.
>
>
>
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-----------------------------------------------------
Dylan Williams               <dylan@...>
NIST 818.01                  <dylan@...>
325 Broadway                 [+1] (303)497-3138 (TEL)
Boulder CO 80305 USA         [+1] (303)497-3970 (FAX)
http://www.boulder.nist.gov/div813/dylan/
-----------------------------------------------------

Visit the new MTT-11 Measurement Website at www.mtt.org/measurements for
answers to all your microwave measurement questions. You will find oodles
of useful measurement links and information, as well as nine friendly
measurement forums moderated by MTT's top measurement experts !

#10

From: "Du Plessis FD <fran@...>" <fran@...>
Date: Tue Feb 1, 2005 9:09 am
Subject: (No subject)

f_duplessis

Offline

I would like to know if you have software available to load the 12-term VNA calibration coefficients from statistiCAL into the HP8510 VNA.

In NISTcal, I am unable to click the "DEEMBED AND SAVE 2-PORT PARAMETERS" button. The "devices in this directory" indicator does not switch on. I am not sure in what format file the device must be, but is currently named dut.s2p. In the "calibrate 2-port" menu there is another indicator between the thru and reflect indicators called the "Switching Terms File". The text-box is hidden on my PC (windows XP) and I am not sure what to enter there. I think that I understand the rest of the program. It would be nice to have a test example.

Is there a publication available on the optimum number of lines for a multiline trl calibration or the effect of using more lines. On page 1212 of “IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 39, NO. 7, JULY 1991, A Multiline Method of Network Analyzer Calibration, Roger B. Marks, Member, IEEE” it states:

“Although we have no proof, an

optimal design seems to require one line to be a quarter

wavelength long at the band center and the other line to

be three times that length”.

Has further research been done in this field and is there a rule of thumb?

Thank you.

From: Dylan Williams <dylan@...>
Date: Sat Jun 19, 2004 2:11 am
Subject: Re: substrate loss modelling

dylanmtt

Offline

Dear Indrajit,

You might look at this paper:

D. F. Williams, M. D. Janezic, A. Ralston, S. List, "Quasi-TEM model for coplanar waveguide on silicon," 1997 EPEP Conference Digest, pp. 225-228, Oct. 27-29, 1997.

You can find it easily enough on my website.

I hope it is helpful,

Dylan

At 12:33 PM 1/3/2004, you wrote:

hi all,
I am a masters student at Indian institute of
science, bangalore and am working on RF MEMS based
distributed phase-shifter.
I had a doubt regarding the modelling of the
substrate losses in a periodically loaded transmission
line.
Is there any possible way to find an equivalent
circuit for the substrate losses, probably some
resistance(depending on the measured attenuation
values) can be incorporated in the equivalent circuit.
Please clarify.


Also do you have any information regarding the effect
of DC bias on substrate losses i.e. when we apply DC
to the central conductor in CPW,for actuation, does it
effects the substrate loss .


Thanks
Indrajit

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From: "Mr.Indrajit Paul" <paulindrajit@...>
Date: Sat Jan 3, 2004 6:33 pm
Subject: substrate loss modelling

paulindrajit

Offline

hi all,
  I am a  masters student at Indian institute of
science, bangalore and am working on RF MEMS based
distributed phase-shifter.
   I had a doubt regarding the modelling of the
substrate losses in a periodically loaded transmission
line.
Is there any possible way to find an equivalent
circuit for the substrate losses, probably some
resistance(depending on the measured attenuation
values) can be incorporated in the equivalent circuit.
Please clarify.


Also do you have any information regarding the effect
of DC bias on substrate losses i.e.  when we apply DC
to the central conductor in CPW,for actuation, does it
effects the substrate loss .


Thanks
Indrajit


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From: "Mr.Indrajit Paul" <paulindrajit@...>
Date: Sat Jan 3, 2004 6:28 pm
Subject: hi i want to jin this group.

paulindrajit

Offline

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From: "Halsey Taylor" <wesbrodsky@...>
Date: Sun Apr 25, 2004 3:26 pm
Subject: MTT chat groups on IEEE Online Communities?

halsey_01

Offline

I am curious as to why the MTT chat Groups are not part of the
IEEE Online Communities; for information go to:
https://www.ieeecommunities.org

From: "BOUDIAF,ALI (A-NewEngland,ex1)" <ali_boudiaf@...>
Date: Mon Feb 4, 2002 6:25 pm
Subject: RE: Duplicate?

ali_boudiaf@...

Hi Dylan,

It's been a while...!, I tried to use the macro that you've sent to me
that makes the transformation from S4p to your program format, unfortunatly
I was not successful. Do you want me to send you the measured files in S4p?

I tried to loggin the MTT-11 web site but I do have a problem right now, do
you know how to recover the ID and the password ?

Regards
Ali

-----Original Message-----
From: Dylan Williams [mailto:dylan@...]
Sent: Monday, February 04, 2002 11:14 AM
To: mtt-11@yahoogroups.com
Subject: Re: [mtt-11] Duplicate?

Hi Roger- Jeff was working on setting up the question and answer "clubs" we
discussed earlier. The first step was understanding how the yahoo sites
work, so he asked us to be his guinea pigs while he figured out what he
could do within the yahoo structure. Jeff is now working on a sample web
page for the clubs that will allow IEEE members to do things like sign up,
submit a question, browse responses, and look through a bibliography. He
was not trying to recreate our internal MTT-11 discussion group. Dylan

At 08:57 AM 2/4/2002 +0000, you wrote:
>Hi all:
>
>We seem to have created a duplicate group since mtt-11 already
>exists!!!!!!
>
>Regards,
>
>Roger.
>
>
>
>
>
>
>To unsubscribe from this group, send an email to:
>mtt-11-unsubscribe@yahoogroups.com
>
>
>
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

-----------------------------------------------------
Dylan Williams               <dylan@...>
NIST 813.01                  <dylan@...>
325 Broadway                 [+1] (303)497-3138 (TEL)
Boulder CO 80305 USA         [+1] (303)497-3970 (FAX)
http://www.boulder.nist.gov/div813/dylan/
-----------------------------------------------------

To unsubscribe from this group, send an email to:
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Reply | Forward | Messages in this Topic (3)

From: Dylan Williams <dylan@...>
Date: Mon Feb 4, 2002 4:14 pm
Subject: Re: Duplicate?

dylan@...

Hi Roger- Jeff was working on setting up the question and answer "clubs" we
discussed earlier. The first step was understanding how the yahoo sites
work, so he asked us to be his guinea pigs while he figured out what he
could do within the yahoo structure. Jeff is now working on a sample web
page for the clubs that will allow IEEE members to do things like sign up,
submit a question, browse responses, and look through a bibliography. He
was not trying to recreate our internal MTT-11 discussion group. Dylan

At 08:57 AM 2/4/2002 +0000, you wrote:
>Hi all:
>
>We seem to have created a duplicate group since mtt-11 already
>exists!!!!!!
>
>Regards,
>
>Roger.
>
>
>
>
>
>
>To unsubscribe from this group, send an email to:
>mtt-11-unsubscribe@yahoogroups.com
>
>
>
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

-----------------------------------------------------
Dylan Williams               <dylan@...>
NIST 813.01                  <dylan@...>
325 Broadway                 [+1] (303)497-3138 (TEL)
Boulder CO 80305 USA         [+1] (303)497-3970 (FAX)
http://www.boulder.nist.gov/div813/dylan/
-----------------------------------------------------

Reply | Forward | Messages in this Topic (3)

From: "rogerpollard" <r.pollard@...>
Date: Mon Feb 4, 2002 8:58 am
Subject: Duplicate - correct

rogerpollard

Offline

Sorry ... the existing group is labelled mtt11. (It's been up since
May last year!)

From: "rogerpollard" <r.pollard@...>
Date: Mon Feb 4, 2002 8:57 am
Subject: Duplicate?

rogerpollard

Offline

Hi all:

We seem to have created a duplicate group since mtt-11 already
exists!!!!!!

Regards,

Roger.

Reply | Forward | Messages in this Topic (3)

From: Jeffrey Jargon <jargon@...>
Date: Fri Feb 1, 2002 7:46 pm
Subject: First test message

jeff_jargon

Offline

Dear Newsgroup Members,

I thought I'd try sending the first message as a test since we have 9
people signed up so far. Feel free to post to the newsgroup with any
comments or questions. After we're convinced that this type of newsgroup
works satisfactorily or we make modifications, I will begin working with
Dylan Williams in starting our first specific Measurement Club, dealing
with on-wafer measurements. It will be a bit more involved than the general
newsgroup, so I figured I'd start with this general one first.

Best regards,

Jeff