SDR and virtex 4 sx35

[asraf]

hai there,
my name is asraf and im from malaysia.currently im working on software defined radio implemented in FPGA.
im a new beginner to FPGA and wondering which FPGA board shall i use to implement the SDR?wheter virtex 4 or spartan 3e?
i also need to know whether i have to buy any extra module to support the FPGA board to make the SDR workout.
please reply to me as soon as possible.tq

 

[amitjagtap]

SDR, means you have to have big FPGA that too with lots of DSP slices and BLock RAM. Again Support of hard or soft microprocessor
will be much helpful. Selecting Virtex 5 FPGA will be good...But if this is first time.... you can go for V4 to generate and test independent module.
Well for testing your code you will require good signal generator and DSO. Let you first start with basic module development. All the best.

 

[asraf]

thank you for your reply Mr amitjagtap. im still wondering whether i have to use IF module and RF module with the virtex 4 as Baseband module to test my generated QPSK modulation ? is there anyway other way for me to test my code? and i have another problem : now i only have virtex 4 sx35 ML402 board.im not sure how to integrate the board(virtex 4) with IF and RF module as RF front end.please help me.im a new beginner.

 

[amitjagtap]

Asraf,
you should have RF front end before virtex4 kit. Which will receive from antenna, down convert the signal sample it. and provide you a I & Q signals in digital. these you can use in FPGA. Or If you have signal generators which directly generate desired digital IQ signals. One more way is you use your QPSK code in MATLAB with MATLAB DSP modules and simulate it, Fine tune it......
Hope this help you.

 

[Scrts]

Remember that You will also need a good op-amp (probably variable gain) and a fast and accurate ADC before FPGA. I don't know the frequency You want to use, but for SDR it will definitely be fast. Anyway, maybe You have some resources to share to read about SDR implementation in FPGA? For output, You can either use an external DAC, which is much cheaper at the same speed comparing to ADC or do a synthesizable DAC and RC circuit on the output.

 

[asraf]

thank you for your reply.here i attached a link so that so can view and give your comments regarding the SDR implemented in FPGA.thank you so much

**broken link removed**

 

[amitjagtap]

Asraf, the card DG4000 is the CPCI RF front end card... It has only ADC & DAC, Low noise Amplifier...etc. This card will work with other cards like Digital signal processing card (Most probably FPGA based) with same form factor CPCI in CPCI chassis. All signal processing required for modulation and demodulation of BPSK, DPSK, QPSK, OQPSK, 8PSK, MSK, GMSK, FSK etc will be done in DSP card. and respective signal is given to this DG4000 card...
Checkout RT logic might be having this DSP in CPCI form factor too.
Check this: http://www.rtlogic.com/datasheets/RTL-DST-DG5000.pdf

 

[asraf]

im quit confused here.if i want to use the DG4000 so i have to have the chasis first rite? i cannot connect the DG4000 with xilinx board or direct to pc rite?
how if i want to use the following board to implement the SDR?please revue the link and give your comment. thank you so much for your help

**broken link removed**
**broken link removed**

 

[amitjagtap]

As GD4000 has PCI connection on one side (you can see a strip of connector called Compact PCI) , you can connect it to PC or some other FPGA with PCI interface. But for this (with PC) you will need drivers to drive this PCI card.
Check this for more details: http://www.rtlogic.com/datasheets/RTL-DST-DG4000.pdf
But as per my knowledge these cards are especially designed in CPCI 3U form factor, so that integrated in a system with other CPCI cards, so that load can be shared....
For your understanding see this 3U cPCI chassis with 6 slots... it means you can plug 6 cPCI cards..lets say one is power card (mandatory), second - Master CPU or control card, Third: DSP card, Fourth: RF front end card (DG4000) etc.... All these cards are connected to each other through PCI interface, according to backplane....
**broken link removed**
Hope you got some idea.......
---------------------------------------
Combining DSPs and FPGAs in next-generation multimode wireless handset designs
LYRtech Virtex-4 FPGA Software Defined Radio (SDR) Development Platform
------ These are good option as compared to DG4000.
Best of luck

 

[asraf]

i get the idea.but is there any other way for me to have RF front end in separate module so that i can integrate it with my xilinx virte sx 35 board?

 

[amitjagtap]

Yes you can go for any customized low cost RF front end... or you can build it by your own..In first, don't try complex things..
Make things as easier as possible.

 

[asraf]

need your advice for the following board.can i use it to program HDL code to become QPSK demodulator? thank you

**broken link removed**

 

[cisco32544]

I'm in the same position as you. I purchased a FPGA with the ultimate goal of wanting to make an SDR. I purchased the SP605 which has limited DSP slices, but it was a rather cheap board and hopefully I will learn enough from this board to move up to a more advanced board. Right now I'm taking baby steps and am learning how to interface the FPGA with a DAC to make a function generator.

Take a look at: www dot epiq-solutions dot com/product_detail.php?line=Bitshark&product=Bitshark_FMC it's FMC based RF tuner that covers 300MHz - 4GHz. The FMC interface should work with a majority of the Xilinx development boards, it's LPC too which means you can use a lower-end board. You won't be able to transmit with this as it's receive only, but the FMC version (there's also one specifically for the USRP) includes a reference design which you should be able to learn a great deal from.

There's some other vendors out there like 4dsp.com but they're a little expensive. If you want cheap you can also go the Texas Instrument route. They have ADC development boards for $300 depending on what kind you want. They also have a rather handy FMC adapter for their development boards, not sure if they offer reference designs though. Perhaps it would be easier to forgo the tuner part and stick with direct conversion in the beginning.

Please keep us posted with your progress, I'm sure there's a number of us here (including me) that are interested in your results.

Cheers

Sorry about the link, as a first time poster this website won't let me post a link. :???: