pavan
New Member
Posts: 1
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Post by pavan on Nov 4, 2005 19:13:16 GMT -5
Hi,
I am confused on how to do you find the number of basis functions needed to represent the given dataset of signals. For example for 8 ary PSK the minimum number of basis functions needed is two. How do you find that?
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Post by charan langton on Nov 7, 2005 12:31:52 GMT -5
Most common basis functions are a sine and a cosine. The condition of a set of basis functionsis that they be orthogonal to each other and to all in the saet. How you find them is limited only by your imagination.
Walsh codes are an example for basis functions used in CDMA.
Charan Langton
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disha
New Member
Posts: 3
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Post by disha on Nov 23, 2005 10:50:20 GMT -5
basis functions have two properties:
1.they r orthogonal to each other.
2.their energy is unity.
so,for the signal constellations you can find out the basis function by using rigid methods like gram schmidt or by intuition this way:
suppose u have 3 signals,two of them have some common area/overlapp =>they are a linear combination of each other ,and hence the dimension will be less than 3.so u know it has 2 basis functions,commonly they r sin and cosines.
i hope this helps
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