using 2nd wifi modem as a wifi bridge to access to net

can someone help me out too ?

i have these two wireless modem router
my BSNL connection is connected with ZTE ZXDSL 531B
and another extra wireless modem router i have is Huawei MT841 ,

i am using 531B at my home but in some area in my home the network doesent reaches , so i want to connect my extra mt841 wirelessly with my 531B and then use the internet in the low network area using mt841 ...

please help

i am attaching the image of what i want ..

*img405.imageshack.us/img405/9213/4202001.png