Pseudoinverse of matrix...

Status
Not open for further replies.

vkekk

Full Member level 3
Joined
Mar 30, 2007
Messages
159
Helped
5
Reputation
10
Reaction score
4
Trophy points
1,298
Activity points
2,211
what is pseudoinverse matrix and in what way it differ from inverse matrix.

For example , The pseudoinverse of channel matrix, H is

H' = ( H*H)^-1 H*

Where H' ---- pseudoinverse of channel matrix, H.

Can anybody explain me to understand the above equation (i.e in what way pseudoinverse work , ( H*H)^-1 H* )
 

Let y = Hx be your system equation where x is the input and y is the output.
If you have inv(H), then your system equation is easily solved by doing x = inv(H)y. However, we cannot have inv(H) directly in many of the real applications. That is where the pseudo inverse comes from.

Although you don't have inv(H), you can change y = Hx to H'y = H'Hx which in turn x = ((H'H)^-1)Hy. In deed, x is the famous 'least square approximation'. Therefore, to be precise, x_ls = ((H'H)^-1)Hy where x_ls is the least square solution and ((H'H)^-1)H is the pseudo inverse of H.
 

Status
Not open for further replies.
Cookies are required to use this site. You must accept them to continue using the site. Learn more…