C 1

C 2

C n

A 1

h 11 k ¯

h 12 k ¯

h 1 n k ¯

A 2

h 21 k ¯

h 22 k ¯

h 2 n k ¯

A m

h m 1 k ¯

h m 2 k ¯

h m n k ¯