RF Cascade Workbook for Excel
RF & Electronics Symbols for Visio
RF & Electronics Symbols for Office
RF & Electronics Stencils for Visio
RF Workbench
T-Shirts, Mugs, Cups, Ball Caps, Mouse Pads
Espresso Engineering Workbook™
Smith Chart™ for Excel
|
|
Receiver system design - RF Cafe Forums
|
Microstrip
|
Post subject: Receiver system design
Posted: Wed Apr 12, 2006 8:38 am
|
|
Joined: Wed Apr 12, 2006
8:21 am Posts: 4 |
Hi guys. I'm getting ready to embark on one of my
1st receiver design projects (2nd year out of engineering
school - MSEE). They taught us about receiver budgets,
but most of those classes were taught by TAs that
had never really designed anything in real life.
I' going to need some software to help out. Anybody
care to suggest something other than the $10k programs
like MDS et al? I'd like to buy this myself so I
can use it at home.
Here's the kind of parameters
I'm looking to plan: Gain Noise Figure
Intercept Point 1 dB Compression Point Downconversion
Filtering BER (maybe but not)
Can anyone
suggest a good book on the subject that convers
strategy?
Thanks.
Eric
|
|
|
|
|
JimB |
Post subject:
Posted: Thu Apr 13, 2006 11:10 am
|
|
Joined: Mon Apr 10, 2006
12:07 pm Posts: 3 Location: Harrod, OH
|
Take a look at some of the free vendor software
available. I've used Agilent AppCAD and Cascade32
from Spectrum Microwave, both of which I believe
are linked through RF Cafe. I've also used an Excel
spreadsheet passed down through co-workers with
changes I've made. It's created from the basic cascaded
noise figure and intermod equations. Also, I believe
Kirt has a spreadsheet for a small fee. Doing your
own spread sheet would be very instructive. Use
one of the other programs mentioned as a double
check.
Keep in mind that a mixer will add
out of band noise unless that is filtered out of
the applied signal.
Filters can be handled
by allowing for a bandwidth term in the spreadsheet.
There will be some manual tweaking of the equations
but it will assist you in seeing the effects of
a 5 MHz BW filter and a 20 MHz BW filter.
None of the mentioned software does BER, however,
that is dependent upon the SNR and SFDR you have,
so you should be able to get close.
Also,
be aware that the simulations don't typically take
into account component to component variations and
also rely on ACCURATE data at all frequencies involved.
This means a lot of bench testing of simple amplifiers.
(You haven't lived until you've taken intermod data
on a mixer over temperature and LO drive for ten
units and then find there is no pattern to the distortion
products or losses that can easily be quantified
or described in any equation.)
Temperature
drift and stage to stage mis-match need to be taken
into account also.
To sum up, your best bet
is to get one of these software packages and start
using them with component manufacturer's data, building
small functional blocks, always comparing simulation
with measured data.
GOOD LUCK!!
_________________ Jim Beckford RF Engineer
|
|
|
|
|
jaslovkel |
Post subject:
Posted: Tue Jul 10, 2007 11:00 pm
|
|
|
Captain |
|
Joined: Tue Jun 26, 2007
10:27 am Posts: 21 Location: Dallas, TX
|
Just a follow up to the previous post:
Another
program which can be used is SystemView by Elanix.
It has proven to be pretty accurate for system level
design in the few projects I have used it for. Another
program you can use is the Simulink portion of Matlab.
Although it does cost some money to get licenses
for these, you can install these on your PC at home
and they won't set you back $10k. It will definitely
take some getting used to and some trial and error
before you are good with these programs, but in
addition to the aformentioned software, these programs
are definitely starting to provide good systems
with decent examples in the nominal libraries.
Hope this helps.
-J
|
|
|
|
|
RFDave |
Post subject:
Posted: Wed Jul 11, 2007 9:03 pm
|
|
|
Captain |
|
Joined: Sat Apr 22, 2006
11:14 pm Posts: 20 |
I've written a bunch of receiver and transmitter
spreadsheets over the years, and you can certainly
calculate most of the parameters you want in a spreadsheet
as a starting point. I'd recommend Dr. Egan's Book
"Practical RF System Design" as an excellent starting
point. It's the only book I've come across that
covers spreadsheet analysis.
Dave
|
|
Posted 11/12/2012
|
|
|
|