Transformation from analog Lowpass filter to Bandpass filter is 
obtained by following steps
1 - desing low pass filter having specifications of bandpass filter
2 - obtain transfer function of lowpass filter
3 - subsitute
s' = [(s^2+wo^2)/s] into Lowpass Tansfer fn to obtain banspass 
Transfer fn.

but how can we transform a BP filter to Lowpass filter in analog 
domain.....
if anyone has an idea ...plz repond
awaiting...