Comments on: Young’s model for Rayleigh fading

By: Mathuranathan

Mathuranathan — Wed, 05 Dec 2012 06:35:53 +0000

Hi Jasper,
Please check my reply for one of the similar topics in our forums for implementing a time varying channel.

https://www.gaussianwaves.com/forums/topic/time-varying-channel/

By: Jasper Hatilima

Jasper Hatilima — Sun, 02 Dec 2012 15:00:14 +0000

Hey Mathuranathan, I am implementing differential space time modulation and it’s purpose is to do detection without CSI. I have managed to implement it with a time invariant channel but now I want to see how it performs in a slow time varying channel at various doppler spreads….and the theory says I should use the Jakes model to have a relationship between one channel matrix to the next…by multiplying one channel matrix by some value obtained through zeroth order bessel function of first kind….But it just doesn’t give sensible results 🙁 Kindly assist on this implementation of a time varying channel that depends on doppler spread using Jakes model.

By: Upul

Upul — Wed, 16 May 2012 12:59:26 +0000

In reply to Mathuranathan. Thank you very much for your support...

By: Mathuranathan

Mathuranathan — Wed, 16 May 2012 12:51:54 +0000

In reply to Upul. Hi Upul, Please follow this excellent tutorial FFT/IFFT in OFDM In the meantime, I might try to make an article.

By: Upul

Upul — Wed, 16 May 2012 12:03:09 +0000

In reply to Mathuranathan.

Basically I just need to know how FFT and IFFT works to compute Fourier transform and Inv. Fourier transform in discrete domain.

As a example ,lets say we want to model OFDM Transmission using FFT/IFFT (lets say in MatLab). Can you explain the approach I should follow in order to use FFT and IFFT at receiver and transmitter with out using direct formulas?

Thank You.

By: Mathuranathan

Mathuranathan — Wed, 16 May 2012 11:38:14 +0000

In reply to Upul. Can you elaborate ?

By: Upul

Upul — Wed, 16 May 2012 10:54:17 +0000

Hi,

Could you please explain how we can use FFT and IFFT in order to solve specific problem in discrete domain? I’m glad if you can publish another post for that.

Thanks.

By: Kharis-aki

Kharis-aki — Sun, 12 Jun 2011 23:02:14 +0000

well actually I’m planning to do it in vhdl for test bench. but I got the idea. Thank you sir

By: Kharis-aki

Kharis-aki — Sun, 12 Jun 2011 19:02:14 +0000

well actually I’m planning to do it in vhdl for test bench. but I got the idea. Thank you sir