Measuring RF and EMI

[pedja089]

Hi,
I'm starting few project which include Rf MCU(eg RfPIC, CC430FXXX at 868MHz), and 3G GSM modems...
I need test equipment for measuring RF output, from boards, and antennas, and EMI for preliminary test for CE/EMC/etc...
Can some one recommend me some test equipment?

I found couple instruments, but I'm not sure if they are suitable
**broken link removed**
Is this frequency range of this spectrum analyzer enough to take measurements on GSM antennas?
I'm concerned about harmonics...
For EMI measurement I found this
**broken link removed**
but I'm not sure which version I need...
On board usual there is DC/DC converters, some analog circuit, and MCU. I'm wory about MCU...
Because they work on frequency up to 30MHz...
Should I use 30MHz version of EMI spectrum analyzer? Or 1 MHz option is suitable?
Any help appreciate...
Thanks.

 

[FvM]

The Arronia analyzers are working partly different from industry standard instruments. They don't implement full frequency selection, trying to identify each frequency component by a specific modulation algorithm. My impression impression is that this doesn't work well for some kinds of EMI measurement problems. I suggest to buy a used Agilent or other known quality spectrum analyzer.

I made some RF transmitter pre-compliance measurements with a customer's TTI PSA2701. Although it has some limitations compared to benchtop SAs, it keeps all speciications accurately.

The Aaronia antennas aren't bad. I'm using a Hyperlog 4040 for most >400 MHz measurements.

Most EMI problems with microcontrollers are radiated emissions in a several 100 MHz range.

 

[pedja089]

Thanks... I'm hoping to get different answer...
Agilent and similar spectrum analyzer is really out of mu price range.
I'm found PSA2701T in Farnell, and price is about 2000€.
So, with 2 Arronia SA I get much wider frequency range for same price as PSA2701T, but did I really need it? I'm not familiar with that equipment.
I can't find another spectrum analyzer which is in my price range.
So should I buy PSA2701T or 2 Arronia SA's?

 

[FvM]

If you consdier Aaronia, you should absolutely arrange a way to test if it's suitable for your purposes before buying the instrument. Ideally, you should do that with any other device, too.

 

[pedja089]

I'm trying to do that... Probably I can get this bundle
**broken link removed**
Do you have any advice for tests? Any advice on what to look for?
Thank you very much.

 

[vfone]

I am confused with the price you got from Farnell.

Check the price list from TTi where a PSA2702USC (12GHz) is 1342 €. Do I miss something?

https://www.tti1.co.uk/products-tti/price-tti-euro.pdf

 

[FvM]

PSA2701T is the previous model. Farnell hasn't the new one, I see a Farnell price of 1260 €.

I didn't yet get hands on PSA series II, before buying an instrument, one should probably check the features of the new series.

PSA2702 is still 2.7 GHz, there's apparently a 12.7 typo in the price list.

 

[pedja089]

We must pay customs fee, because we aren't in EU...
I'll check everything I can, and post when finally decide what to buy.
Thank for info.

- - - Updated - - -

I just found distributors for Aim TTi in my country. Ill contact them, and ask for presentation, for PSA2702USC(12,7GHz version).
Thank again.

 

[FvM]

It seems like PSA series II is pretty new, and not presently available in every place. An important change is that it doesn't use a Palm handheld computer inside rather than a TTI designed controller.

 

[pedja089]

That fine for me. I can wait until they get one.
I'm just preparing for next year.

 

[E Kafeman]

I have a Aaronia HF-60100X SA (-9GHz). It is hardly not usable to anything else then as a RF detector for stable carriers. Noisy bursts are not reliable detected.
Every 10 / 20 MHz for swept bandwidth do it have a more or less blind spot. Probably a kind of zero IF.
Noise floor is also a bit special. See attached photo where a 50 Ohm resistor is input load.

This type of spectrum can not be included in a serious measurement report.
Aaronia did specify snr around 4.9 GHz in data sheet. Not really honest.
It have poor programming interface so it is not simple to use it in combination with other EMI measurement equipment such as tracking signal generators or turn-tables. Current firmware and software is rather buggy and experimental.
Besides that do it work for my main needs, detecting stable and and relative strong harmonics. It is small, cheap, noiseless and takes almost no place on lab bench.

Do also have a Anritsu MT8801 with SA option. Old but much more professional tool, GPIB interface, can handle relative strong signals, half the price compared to Aaronia (used at Ebay) but max frequency is 3 GHz which not is enough for my needs (mostly cell phone related harmonics). Almost all of these MT8801 have a very weak contrast-less display but it is possible to use external monitor.
A alternative new SA in similar price range is ATTEN AT5030 (Ebay), do not know anything about it but as it is including tracking generator and a price below US $2k is it very interesting.

Agilent, R&S and similar are expensive labels, support and calibration makes the instrument twice as expensive, but for qualified measurements above 3 GHz have I not found any alternative. I mostly have relative old Agilent/HP equipment, which can be bought cheap but it is problem with calibration and spare parts.

 

[FvM]

I have a HF-60105-V4 (Q2 2009 production), which exposes quite similar flaws. It has a wideband detector option, I'm showing below a validation measurement for a 10 Mhz to 4 GHz, I leave it to the readers decision, if the function is of much use.

The wideband detector frequency response can be possibly seen as an annoying but not so important point, the level error at 434 MHz can't. Most alarming, you get two a completely different curves after switching the device off and on. Aaronia support guys said something about software problems etc. I must confess, that I didn't make yet another attempt to fix the problem with a software update. I decided for a used E4407 some months later.

I'm under the impression that the strange behaviour of Aaronia SAs is related to the measurement method described in DE19530812 https://worldwide.espacenet.com/pub...m&locale=en_EP&CC=DE&NR=19530812A1&KC=A1&ND=4

Apparently, too much "undesired (and desired) components of the received signal are removed by filtering or subtraction".

 

[pedja089]

I'm definitely disappointed with Aaronia...
I hope that PSA2702USC is much better...

 

[Aimtti]

I'm definitely disappointed with Aaronia...
I hope that PSA2702USC is much better...

The PSA S2 is very new and demo models are still rather limited. But please contact us at aim-tti and we will do all we can to get a unit to you to be evaluated. The RF performance of the PSA S2 models is the same as the original T versions. However the user interface has been improved and we now have USB interfaces for transfering data and using the Big Screen software you can easily display the screen on your PC.

 

[biff44]

unless you needed the handheld feature, why would one waste money on a toy spectrum analyzer. You can buy a used agilent e4406a spectrum analyzer on ebay for $1100. There is free data capture software to work with the E4406 available at http://www.thegleam.com/ke5fx/

ebay has 8562a's that go to 22 ghz in the $4000 range, 3 GHz anritsus for $2000....

 

[pedja089]

Project was delayed. So we didn't buy anything...
Thanks for your help.