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Both PCB antenna and external

Iron

Open Space, Clustered Buildings

Iron

thank you for an interesting info

Iron

or you can duplicate the fader circuitry for bidirectional channel modeling.

Blogger

you can have a return path for the ACKs via just RF cabling or via RF cabling plus attenuators.

Blogger

how are ack/nacks received for bidrectional faders? do you have another connection with a variable attenuator not shown in the diagram?

Iron

thanks fanny, rob, digikey and ieee

reverberation environment is also referred to as 'isotropic'. we will discuss more tomorrow.

Blogger

There were reverberation specific models proposed for reverberation chambers where it is difficult to emulate clusters.

Blogger

Geometric models are defined usinga physical model detailed in the standards.  It takes a lot of work to determine what models are more realistic.  Typically manufacturers want to use whatever models give them the highest throughput.

Blogger

Thanks Fanny for the excellent program. Also, thanks everyne for attending and commenting. See you tomorrow.

Blogger

Yes - correlation matrix is indicative of MIMO channel capacity.

Blogger

Can you say something about the importance of the OTA models being geometric vs. classical correlation matrix implementations? How does this affect implementations in anechoic chambers vs. reverberation chambers?

Iron

Doppler filtered noise is what makes TDL coefficients time-variable

Blogger

so a correlation matrix is a means of how well the usefull signal is detected or not?

Iron

Slide 25 has some explanation of the correlation matrix computations.

Blogger

Correlation matrix is part of the computation of the coefficients for each TDL (tapped delay line).  It is a function of TX and RX antenna array spacing.  The explanation gets into some heavy matrix math.  

Blogger

When testing for muti-user cases, you use multiple users or you also sometimes emulate a number of similar of different users?

Iron

Doppler filter shape and bandwidth are defined by the standards. Filter bandwidth is a function of velocity and center frequency

Blogger

could you please define more spatial correlation and polarisation matrix? if it is related to the transfer function and the polarisation pattern of the antennas?

Iron

Doppler is emulated by putting white AWGN through a specifically shaped filter

Blogger

to measure MIMO PDP (impulse response) we need to fire with a MIMO transmitter and detect with a MIMO receiver.

Blogger

How is the doppler emulated?  By varying the delays in an element?  You aren't creating waveforms from scratch, are you?

Iron

?? Fanny, I think it was slide 13 where you mentioned some mathematician's name who did theory on this.  Who was that?

Platinum

@spencestan - There is only 1 evaluation form for the entire course (Monday - Friday). It is not one per day. Thanks!

 

Yes - we can build any channel model.  Commercial faders typically offer standards based models and some capabilities to define your own model based on the channel impulse response

Blogger
Spencestan: I think there is only one evaluation form for each week's class.
 
Blogger

Forgot most of this stuff since I studied worked with it. Good reminders -- might as well be new stuff. ;-)

Iron

 

I always have to do homework after Fanny's presentations.

Iron

Kurting, make sure you actually downloaded a PPT file and not saved the web page itself. My PPT opened fine.

Iron

More stuff to digest, I know very little about MIMO. Thank you very much Fanny.

Iron

Given a certain testing office/house, can you build a detailed model of it in a fader, or the modelling is more generic?

Iron

40MHz; probably 64QAM (?)

Iron

octoScope has an RF based fader that can emulate static model of a house, for example.  For programmable channel models, you may need to downconvert the signal in order to get it to a sampling rate for computing logic to keep up.

Blogger

@spencestan, you are supposed to do the evaluation after the last lecture on Friday

Platinum

Thanks Franny

This is good stuff. long time since impulse step response

Iron

The evaluation form link is yesterday's lecture (already completed).  changing to today's date doesn't fix it either

Iron

Thanks Fanny, Great lecture

Iron

Thank you. A very interresting presentation

Iron

Question: Why does the fadder use Demod / Mod?  Shouldn't it just act on the RF as it happens in the real world?

Iron

Thank you very much!

Iron

Fanny, thank you. this is a lot of information to absorb, but very interesting

Iron

Wow.  The degree of complexity is just mind boggling.  Why would one want to design their own algorythm?

 

Thanks.

Iron

Thanks for the lecture

Iron

thank's Fanny, thank's Rob!

Iron

@Kurting

I have had problems once or twice in the past but not today

 

Iron

BW typically encountered is the BW of 802.11 channels

Iron

Thank you Fanny, Design News, and Digi-Key.
That was quite a firehose to drink from.

Platinum

Thanks Fanny, Rob & Digikey.

Iron

Thanks for the lecture!

Iron

Thanks for the lecture

Iron

has anyone had difficulties to open the today´s silde deck using power point application?

Iron

course evaluation Form link not working correctly.

Iron

Thank you Fanny.

Thank you Rob

Iron

I don't currently use RT

Iron

fan's? no project yet.  (8% 64QAM) MEANS?

EVM One reference:

http://www.antenna-theory.com/definitions/evm.php

cheers

Iron

We're now on sldie 30.

Blogger

narrow band. 12.5kHz and 25kHz QPSK-256QAM

Iron

 Fanny's queston:

What is the channel width and highest order modulation your radio technology uses?

Blogger

not familiar with evm

Iron

learnred about EVM in advanced math course but not how it relates to comm sys

Familiar with Error Vector Magnitude.

Iron

EVM - a measure of TX quality

Iron

We're now on slide 28.

Blogger

We're now on slide 27.

Blogger

@dhajicek, the fourrier spectrum of the noise has high frequency components.  It is where these sum that is in the RF band.

Iron

We're now on slide 26.

Blogger

We're now on slide 25.

Blogger

We're now on slide 24.

Blogger

How do environmental noises sum into signal.  Aren't they outside the receive band?

 

Iron

We're now on slide 22 and 23.

Blogger

We're now on slide 21.

Blogger

We'r e now on slide 20.

 

Blogger

We're now on slide 19.

Blogger

We're now on page 18.

Blogger

We're now on slide 16.

Blogger

is polarization matrix related to antenna polarisation?

Iron

I have got troubles to open the today´s slide deck with power point  application. can anyone help me?

Iron

We're now on slide 15.

Blogger

No bidirectional yet.

Iron

We're now on slide 14.

Blogger

at moment, I don't need bidirectional, too early for mine stage of learning

Iron

Normally no fading used

Iron

not yet.  still learning.

Iron

ATM, manily focus on range; interested in using beamforming

Iron

 

I have kept it simple so far 

 

Iron

fan's? no project at this time

No bi-directional fade

 

Iron

I don't quite understand, the fader block diagrams are just used in oredr to model the fading channel?

Iron

Usually LOS distance not radiational paterns.

 

Iron

Mainly focusing on receiver tests for now.

Iron

Yes, we would need bidirectional

Iron

Not using bi-directional fader

Iron

bidirectional is required

Iron

not yet, still learning

Iron

Is the bottom "Fader Logic" block reversed (i.e. arrows in wrong direction)?

 

Iron

We're now on slide 13.

Blogger

Fanny's question:

Does your application require bi-directional fader (e.g. for beamforming testing) or will you mainly be focusing on receiver testing?

Blogger

Why multiple channels in fader?  Doesn't the single channel emulation cover all the delays and amplitudes?

Iron

symetric channel is only in TDD systems, they are not symetric in FDD systems

Iron

Isn't the channel different for FDD operation?

 

Question: Why doesn't the fadder only act on the RF? Why is there a demod, mod in the path?  Isn't the fadding really acting on the RF in the real world?

Iron

We're now on slide 12.

Blogger

Our antennas are printed.

Iron

We're now on slide 11.

Blogger

Internal for products with external for R&D Tests

Iron

We're now on slide 10.

Blogger

PCB antenna with optional external antenna for some models.

Iron

I largely use modules that incorporate printed or chip antennas, except in some industrial applications)

Iron

PCB printed antennae in mobile device.

Iron

STILL no luck, so I am giving up for today. I will check for the archive later. Have fun!

 

I have used ext antenna exclusively

 

Iron

Use external antennas

Iron

I have not worked with fader. Our antennas are internal.

Iron

printed or chip antenna

Iron

I prefer external antennas

Iron

surface mount antenna

Iron

I use external antennae

Platinum

I have not worked on faders.

Iron

We're now on slide 9.

Blogger

I have not worked with a channel emulator for my testing and most likely will not in the future.

Iron

Fader incorporated in lab test cabinet.

Iron

I have never used a fader or channel emulator

Not currently used, no future use of fader

Iron

 

have never used a fader just fixed value attenuator

 

Iron

No, have not worked with a fader.

Iron

i work only in terms of simulation in Matlab

Do you remember cantena?

Iron

Haven't worked with faders. Should I get into lower-level RF design, I imagine I would.

Iron

never worked with a fader

 

Iron
Possible I might use one in the future
Iron

I have not worked with either.

Iron

fan's? never used or planned to use fader

Never worked with fader. Probably will not use one in the future, but not sure.

Iron

No, I never hear of the term in mimo

Iron

never used, no planned future use

I have not used a fader

Iron

have not worked with faders

 

Iron

I have worked with aTAS/Spirent  fader in the past. 

 

No and probably not.

Iron

We have not used a fader.  We should move in that direction.

Iron

Not directly, other engineers in my company do.

 

Iron

Have not worked with faders

Iron

never worked with fader

Platinum

Lab simulation emmissions shielded box

Iron

Have not used fader

Iron

Still no audio, and I just tried IE as well. Our network is wireless!

Typically inside; office, store, manufacturing.

Iron

Some targeted environments: largely indoors; some industrial (some residential)

Iron

Have not worked with a fader.

Iron

Fanny's question:

Have you used a fader in the past?  Do you plan to use a fader in your testing?

Blogger

indoor and outdoor -- pretty variable conditions

Iron

Residential installation

 

usually work in open space sometimes ground clutter issues

Iron

Manufacturing plant -open space, many reflections

Iron

Outdoors over many miles.

 

Iron

fan's? no project as yet. but would be industrial area.

 

small office and short distance in metal high ceiling manufacturing space

Iron

indoor somewhat open

Iron

Typically indoors in an industrial environment.

Iron

Our environment is Open pit Mining (outdoor)

 

It would be indoors.

Iron

Wide open space but lots of trees within 0.1 mile all around

Platinum

Building to building (campus setting)

Iron

our environment: indoor, open space, office, work areas with concrete block walls.

Iron

Indoors mostly, but can be outdoors. Concert venues.

Iron

We work in indoor environments, but can have receivers on multiple floors in the same building.

Iron
Indoor mostly open warehouse environments
Iron

Indoor and outdoor environments

Iron

We're now on slide 8.

Blogger

Fanny's question:

What environment does your radio operate in?  Open space? Small office?  Other? 

Blogger

We're now on slide 7.

Blogger

I use IE9. Audio is ok.

Iron

We're now on slide 6.

Blogger

Still no audio here but it may be our system.

 

audio is consistant and clear for me

 

Iron

SMDPE -- Post is what you click after you've entered you message in the chat window.

Blogger

We're now on slide 5.

Blogger

We're now on slide 4.

Blogger

If the audio is not working -- for whatever reason -- you can always play back the program as an archive. It is avaible shortly after the end of the program.

Blogger

We're now on slide 3.

Blogger

Unfortunately I am unable to hear audio. Running Chrome, up to date flash. tried many times!

 

slide 4 I think

 

Iron

-The streaming audio player will appear on this web page when the show starts at 2 PM Eastern time today. Note however that some companies block live audio streams. If when the show starts you don't hear any audio, try refreshing your browser. If that doesn't work, try using Firefox or Google Chrome as your browser. Some users experience audio interruptions with IE. If that doesn't work, the class will be archived immediately following our live taping.

Blogger

Good day from So Cal :-)

 

We're now on slide 2.

Blogger

We're now on slide 1.

Blogger

 

audio is live

 

Iron

Hello from rainy and cold Split, Croatia

Iron

Hi all -Audio is live! If you don't see the audio bar at the top of the screen, please refresh your browser. It may take a couple tries. When you see the audio bar, hit the play button. If you experience audio interruptions and are using IE, try using FF or Chrome as your browser. Many people experience issues with IE. Also, make sure your flash player is updated with the current version. Some companies block live audio streams, so if that is the case for your company, the class will be archived on this page immediately following the class and you can listen then. People don't experience any issues with the audio for the archived version.

Good Morning from Calgary

Good afternoon.  It's a balmy 7 degrees here in Minnetonka.

Iron

good afternoon for Detroit

Iron

Hello from Chicago where it's a wind chill of -11 F.

Iron

As a rule my state board does not provide a list of accepted training providers or courses, and refuses to pre-accept any providers. But like the others said, IEEE carries a lot of credibility.

Iron

Hello from FL where it is 80!

Hello from Barranquilla

 

Rob, the state boards decide which continuing ed providers they accept.  PE's need to check their individual state board.  Generally, everyone accepts IEEE.

Iron

Lots of good material in today's slide deck.

Iron

Hello from SW Michigan

Iron

Hello everyone, it is cold in Dayton Ohio also. looking forward to another great lecture!

Iron

CPU, you'd have to check with IEEE about credibility to state boards. But I would guess the IEEE blessing would carry some isgnificant weight.

 

Blogger

-The streaming audio player will appear on this web page when the show starts at 2 PM Eastern time today. Note however that some companies block live audio streams. If when the show starts you don't hear any audio, try refreshing your browser. If that doesn't work, try using Firefox or Google Chrome as your browser. Some users experience audio interruptions with IE. If that doesn't work, the class will be archived immediately following our live taping.

Blogger

My state's rules make no statement regarding whether or not any IEEE PDHs are accepted. They seem to be intentionally vague to let the state board have lots of room to say yea or nay.

Iron

IEEE PdH credits for PE's depends on the rules your state has for PdH.

 

Iron

Hi Rob,

offering the IEEE prof. dev. hours is a good thing. I'd like to submit these hours for Professional Engineer continuing education required training. Having them accepted by IEEE should give them credibility to state boards, I hope. Do you have any comment about that?

Iron

-Be sure to click 'Today's Slide Deck' under Special Educational Materials above right to download the PowerPoint for today's session.

Blogger

Hello from ccccold PA

Iron

Hello from balmy northwest Montana - high 20s, no wind.

Platinum

-You are eligible to earn IEEE Professional Development Hours by attending these courses and participating in the chat function. Additionally, we are no longer using the points system, offering "graduation", or giving grades. The IEEE hours are taking the place of that. There are some important things for you to know about earning the hours. The most important ones are that you need to attend these courses live, you need to attend a minimum of two of them per semester, you need to fill out a course evaluation form within 2 weeks of the end of the class, you need to attend 4 out of the 5 classes per course, and you need to participate in the chat function every day you attend. Please click on the link at the top of this page that says "How do I earn IEEE professional development hours" to read all of these important details and more

Blogger

-Be sure to follow @designnews and @DigiKeyCEC on Twitter for the latest class information. We encourage you to tweet about today's class using #DigiKeyCEC.

Blogger

Hello from Ana, Macedonia

Iron

 

hello from steamy -3F Mishawaka 

 

Iron

Hello from the COLD windy city of Chicago

Iron

Greetings and felicitations!

Iron
Hello from Mahwah, NJ
Iron

Looking for another great lecture from Fanny.

Iron

Good Afternoon. How is everyone doing?

Iron

Hello from Sunny SE Lake SImcoe Ontario Canada. Just -20C -- a balmy spring like day... yeah!

Iron

Hello from Hudsons Hope BC

Iron

Hello from El Paso, TX

Iron

Hello from IA - I wish I was in Albuquerque - it is -10F here.

Iron

-Please join our Digi-Key Continuing Education Center LinkedIn Group at http://linkd.in/yoNGeY

Blogger

Hello from Albuquerque, New Mexico.

 

Blogger


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