These methods wil help to boost your wifi signals but cant guarantee that it will reach upto 0.3km
*.reposition your routeror access point (AP) to avoid obstructions and radio interference. Both reduce the range of Wi-Fi network equipment. Common sources of interference in residences include brick or plaster walls, microwave ovens, and cordless phones. Additionally, considerchanging the Wi-Fi channel numberon yourequipment to avoid interference.
*.upgrade the antenna on your routeror access point. Wi-Fi antennas on most wireless base stations can be removed and replaced with more powerful ones.
*.add another access point(or router). Large residences typically require no more than two APs, whereas businesses mayemploy dozens of APs. In a home, this option requires connecting your primary wireless router (access point) to the second one with Ethernet cable; home wireless routers and/or APs don't normally communicate with each other directly.
*.add a bi-directional Wi-Fi signal amplifierto wireless devices as needed. A Wi-Fi signal amplifier (sometimes called "signal booster") attaches to a router, access point or Wi-Fi client at theplace where the antenna connects. Bi-directional antennas amplify the wireless signal in both transmit and receive directions. These should be used as Wi-Fi transmissions are two-way radio communications.
*.add a Wi-Fi repeater. Awireless repeateris a stand-alone unit positioned within range of a wireless router or access point. Repeaters (sometimes called"range expanders") serve as a two-way relay station for Wi-Fi signals. Clients too far away from the original router or AP can instead associate with the same local wireless network through the repeater.