If you're having trouble connecting to a Wi-Fi hotspot, your home wireless network or another person's network such as in an RV park, there are a couple of different means of boosting the signal.
Relocate your router or wireless adapter. You can boost a signal from a Wi-Fi network by adding a Wi-Fi repeater, adding a high-gain Wi-Fi antenna at the receiving end or boosting the signal from the router from which the signal is originating. First, if you have a home network, place your router as high as possible, such as on a shelf at head level, and see if it improves the signal throughout the house. You can also purchase an external antenna for most brands of routers. If you add an external, outdoor antenna to your router you'll increase the range of your home network. This may not be desired if you are worried about someone hacking your network. However, this may be an acceptable solution to cover a large office building or warehouse, farm or RV park where you grant access.
Add a high-gain Wi-Fi antenna on the receiving end . These are available with gains up to 38 decibels. You typically mount them outside the home on a pole and aim them in the direction of the Wi-Fi network you want to connect to. Many occupants of recreational vehicles and truckers use these to connect to wireless access points that may be up to a mile away.
Increase the Wi-Fi range in your home with a Wi-Fi repeater. These pick up the signals from your home Wi-Fi network and resend them. You normally place a Wi-Fi repeater halfway between your computer and the router. For example, if the router is located in the kitchen in the far end of the house, you'ld place the Wi-Fi repeater at a midpoint in the home to distribute a better signal in all areas.
When boosting your home Wi-Fi network, enable your security settings. Enable WEP or similar encryption keys that prevent others from stealing your Wi-Fi.
Check with the manufacturer of your router or wireless adapter for compatible high-gain antennas that do not violate Federal Communications Commission rules.