Jerome has given one solution.
Here is one more: You can connect multiple STBs to single dish using Multi-Switch. Connection diagram for reference is here - http://www.dmsiusa.com/diagrams/3x4mult1.gif
I am not sure where you will find a multi-switch in India or Bangladesh. But with a dual-LNBF and a multi-switch you can connect 4 or 8 STBs to one Dish. Check this link for Switches- DMS International :: Switches
Advantages of this solution: You need lesser cabling as you only need 2 cables to come inside the house from Dish. LNBF required is cheaper compared to Quad LNBF. But you need to spend extra for switch and connectors.
Here is one more: You can connect multiple STBs to single dish using Multi-Switch. Connection diagram for reference is here - http://www.dmsiusa.com/diagrams/3x4mult1.gif
I am not sure where you will find a multi-switch in India or Bangladesh. But with a dual-LNBF and a multi-switch you can connect 4 or 8 STBs to one Dish. Check this link for Switches- DMS International :: Switches
Advantages of this solution: You need lesser cabling as you only need 2 cables to come inside the house from Dish. LNBF required is cheaper compared to Quad LNBF. But you need to spend extra for switch and connectors.