Question about Gaussian Noise Generator?

Discussion in 'VHDL' started by oscarvhdl, Nov 7, 2009.

  1. oscarvhdl

    oscarvhdl

    Joined:
    Nov 7, 2009
    Messages:
    3
    Hello all,

    I have a problem with this. I need to generate 2bit noise with a gaussian distribution (only 4 possible values, 11,10,00 and 01), for this purpose I'm using a LFSR code with 32 bits that gives 32-bits noise with an uniform distribution. Then, I added ten signals from ten LFSR block, each one of 32 bits.

    The result of this operation gives numbers with 36 bits. If a consider all bits and I plot them using matlab, gives a gaussian distribution. But when I extract only the 2 most significant bit and I plot the result lost all sense.

    Is any other way to obtain with only 2 bit a gaussian distribution??

    Thanks for any possible help
    oscarvhdl, Nov 7, 2009
    #1
    1. Advertising

  2. oscarvhdl

    jeppe

    Joined:
    Mar 10, 2008
    Messages:
    348
    Location:
    Denmark
    Well - with only 4 possible values theres couldn't be much left of the gaussian distribution - how about a 3,4,5 bit value (just for the test of algorithm)
    Jeppe
    jeppe, Nov 7, 2009
    #2
    1. Advertising

  3. oscarvhdl

    oscarvhdl

    Joined:
    Nov 7, 2009
    Messages:
    3
    it has to be with only two bits. I need to obtain (for example, with 1000 samples) a distribution like this:

    11: 150 times
    10: 350 "
    00: 350 "
    01: 150 "

    Thanks anyway
    oscarvhdl, Nov 7, 2009
    #3
  4. oscarvhdl

    jeppe

    Joined:
    Mar 10, 2008
    Messages:
    348
    Location:
    Denmark
    Lets say your LFSR block was 8-bits instead of 36-bit (just for the example)
    Then: 0..127 and 128..255 should be 50% ranges.
    If you compare and detect the range 0..50 could you get 15% (just a quess)
    -----------------------------------51..127 ----------- 35% -------------
    and so on.

    Hopefully it helped you
    jeppe, Nov 8, 2009
    #4
  5. oscarvhdl

    oscarvhdl

    Joined:
    Nov 7, 2009
    Messages:
    3
    Jeppe:

    I was thinking the same, I'm going to do these and I look what hapen.

    Thanks for all :)
    oscarvhdl, Nov 8, 2009
    #5
    1. Advertising

Want to reply to this thread or ask your own question?

It takes just 2 minutes to sign up (and it's free!). Just click the sign up button to choose a username and then you can ask your own questions on the forum.
Similar Threads
  1. MNQ

    white noise generator

    MNQ, Aug 3, 2004, in forum: VHDL
    Replies:
    5
    Views:
    4,614
  2. Peter Strøiman
    Replies:
    1
    Views:
    2,070
    Peter Strøiman
    Aug 23, 2005
  3. Adam Hartshorne
    Replies:
    1
    Views:
    644
    Victor Bazarov
    Jul 9, 2005
  4. Mesvak
    Replies:
    1
    Views:
    683
    Daniel Pitts
    Aug 27, 2008
  5. Jim Weirich
    Replies:
    0
    Views:
    140
    Jim Weirich
    Aug 21, 2003
Loading...

Share This Page