Is it possible to implement a128k Point FFT in a FPGA?

[Circuit_seller]

128k Point FFT

Hi

Is it possible to implement a 128k point FFT in a FPGA.
If yes, which family of FPGAs?

Regards

 

[lucbra]

Re: 128k Point FFT

I've seen 1k FFT and 2k FFT with performance of +200MHz in Lattice's ECP family (FPGA with embedded DSP blocks).
Consult your local Lattice FAE, he will help you in this process.

Regards,

L

 

[Black Jack]

Re: 128k Point FFT

I've seen 1k FFT and 2k FFT with performance of +200MHz in Lattice's ECP family (FPGA with embedded DSP blocks).
Consult your local Lattice FAE, he will help you in this process.

Regards,

L

How many resources are used

 

[lucbra]

Re: 128k Point FFT

Resources for 1024 point complex FFT:
1.4k LUT
1.7k regs

202MHz

 

[echo47]

Re: 128k Point FFT

200 MHz is the clock. 1K FFT takes 1024 clock cycles.

 

[Circuit_seller]

Re: 128k Point FFT

Hi

I have found that there is some IP Cores which implement up to 256k Point FFT in Virtex-II FPGA family from xilinx.


Regards

 

[Ace-X]

Re: 128k Point FFT

I have found that there is some IP Cores which implement up to 256k Point FFT in Virtex-II FPGA family from xilinx.

Could you please provide links here?

 

[Circuit_seller]

Re: 128k Point FFT

Hi

Here is the links:
1- **broken link removed**.
2- **broken link removed**

Download the datasheet, you will find that this IP Core can be used to perfrom FFT by more than 128k point.

Regards

 

[Ace-X]

128k Point FFT

Thanks!

They stated that more than 128K core require special request. Anyway, following data in datasheet it should be not a problem to implement even 1M FFT with V2P100. As to 128K, logic resources of V2P20 should be enough (but not sure about PaR).

 

[Mazi3]

Re: 128k Point FFT

only need one butterfly, which is the same for 16 point fft or 128k point fft, problem is ram...

 

[nj_jack]

128k Point FFT

i find a way to implement rapid FFT calculation.
you can search a document about Walsh-Hadamard transform. it can complete FFT algorithm through creating the relation between them.

 

[mami_hacky]

128k Point FFT

Why the 128k point fft should be computed using an FPGA? did you first think about the possibility of using a for example pentium or even a dsp?
If you are going to use a Virtex-II Pro FPGA for doing such a thing, you should make sure that there is no other solution with lower costs. usually there are some better lower cost solutions.
Look! Virtex-II Pro FPGA is some thing really amazing, Gigabit interfaces, powerpc core, lot's logic resource, and OK! the price is not low. are you willing to pay the price? even when lower costs solutions such as industrial motherboards and dsp dev kits are available?
Would you please tell me, your system's sample rate? I want to caculate if a V2P is really needed.
thanks,
mami_hacky.

 

[Circuit_seller]

Re: 128k Point FFT

Hi

Thank you for your attention.
Our sampling rate is more than 65MSPs, so there is only one way to implement a 128k point FFT in 30ms.

Regards

 

[Ace-X]

Re: 128k Point FFT

Would you please tell me, your system's sample rate? I want to caculate if a V2P is really needed.

Here is one more example: real-time hi-end audio-mixing system with 128 simultaneous audio channels with 128k FFT each. Sampling rate is 56kHz each.

 

[Mazi3]

Re: 128k Point FFT

hint: fisrt analyse the problem. if you are fammiliar with FFT and FPGA design, you can calculate (just sketch), how many MHz you'll need.
for a buttefly, you need 2-4 multipliers, two adders, two subtractors....

sketch pipeline sequence, you'll probably need a lot of ram and wiiiiide bus
maybe using double port ram, you'll need 17 stages...

very costly stuff

have a nice new year anyway