| Author |
Message |
StoppTidigare
Joined: 16 Jul 2002
Posts: 156
Helped: 1
Location: Northern earth
|
 15 Oct 2003 13:00 RF CMOS-chip project |
|
|
|
Hi elektrodians, since I've haven't so much to do at work
I've decided to start a project (5GHz CMOS tranceiver-chip) with a university far away from here.It's a project that I'll do just to learn, and I do it for free, no strings attached...Its just for fun.
The guy who I am having a contact with, suggests a testability project. A built in test that is enabled by the dsp. The test would focus on the RF-front end, and he suggests a simulink/matlab systemsimulation before starting up the design of the RF-parts.
Quote:"The architecture should be integrable such as zero-IF or low-IF so that off chip filters can be avoided"
(??? Don't know what integrable means !)
The tranceiver should be generic so that it can be used for an arbitrary protocol: bluetooth, 801.11b,or whatever
Questions:
i. What kind of tests do I want to do with the help of a DSP ?
My idea is to check if the PLL can lock on each frequency now and then.
Then you might also want to use A/D converter of DSP, to check for SWR somehow (Can it be done on chip ?)
ii. How should the architecture look like approximately ?
(For instance should it be a double conversion system ? Do I need several PLL, because of the frequency hopping ?)
iii. At which abstraction level should the system-simulation be done at ?
I've seen a tutorial on Eagleware's Spectrasys and understand that more or less that I can make rather big blocks of systemcomponents.
Will I be able to model frequency hopping
iv. How does Simulink work, I don't acess it yet, do I have have the Laplacian transfer function when I specify a subsystem, like for instance a filter ?
Kindest regards,
StoppTidigare
|
|
| Back to top |
|
 |
goxy
Joined: 25 Jul 2002
Posts: 268
Helped: 1
|
| 15 Oct 2003 15:05 Re: RF CMOS-chip project |
|
|
|
Matlab has very powerful tools for problems like yours. There are many examples on this theme.
Integrable architecture means that process of modulation/demodulaton is integrable so you no need filter.
You need just one pll with short response.
In Simulink you can get Laplacian transfer function when you specify subsystem.
|
|
| Back to top |
|
|
StoppTidigare
Joined: 16 Jul 2002
Posts: 156
Helped: 1
Location: Northern earth
|
| 16 Oct 2003 7:19 Re: RF CMOS-chip project |
|
|
|
Thanks for the responce goxy, still don't understand
your quote: "Integrable architecture means that process of modulation/demodulaton is integrable so you no need filter"
Does this mean that modulation and demodulation is done digitally, by the way which parts are digital in these software radio things.
regards,
StoppTidigare
|
|
| Back to top |
|
|
buta
Joined: 16 Apr 2003
Posts: 105
|
| 16 Oct 2003 13:44 |
|
|
|
I will read it as the component count is as low as possible because most of the functions are integrated into a chip.
The architecture depends on the system requirement. For example, we use zero IF for 802.11b (2.4GHz DSSS). But we can't use zero IF for 802.11a (5GHz OFDM), instead all 802.11a chips available on the market employ low IF.
|
|
| Back to top |
|
|
goxy
Joined: 25 Jul 2002
Posts: 268
Helped: 1
|
| 16 Oct 2003 14:10 Re: RF CMOS-chip project |
|
|
|
Here you explanations for the start:
http://amesp02.tamu.edu/~boxia/research/bluetooth/papers/low-if%20topo.pdf
http://videos.dac.com/videos/39th/51/51_3/51_3slides.pdf
http://www.agere.com/client/docs/multimode_white_paper.pdf
http://images.rfdesign.com/files/4/0201Mehta76.pdf
http://www.microlinear.com/downloads/PR/news_03_Feb25.pdf
http://www.icsl.ucla.edu/aagroup/PDF_files/dir-con.pdf
Also search by Google and look into chip specifications.
|
|
| Back to top |
|
|
superluminal
Joined: 31 Jan 2002
Posts: 95
Helped: 1
Location: Inside a quantum well
|
| 16 Oct 2003 14:11 Re: RF CMOS-chip project |
|
|
|
"Integrable architecture" means that you should make all of your design using on-chip components only and not to use off-chip filters like SAW filters or alike.
Many challenges you will face to solve these problems. I have a friend that did a TRX at 1GHz , from about 3 years , that can not work with on-chip filter at all . He had to make an off-chip filter to make it works.
As I know , only few companies can make all-on-one-chip TRX without a need for an off-chip components.
Best luck
|
|
| Back to top |
|
|
