I bought a little usb wifi booster but don't know how to use it on public wifi. Since there's no WPA security or such how would I do that? I've read that using a vpn can better allocate the signal. Is that true?
Basic answer is that you cannot boost the signal that you are not generating and is thus under your control. You can receive and re-transmit a signal that is present, this will boost the range that the signal is usable at. The devices used for this are often called signal boosters but in fact the best name is a Range Extender.
These small USB devices are useful to allow you to boost the signal locally to you to use other devices eg. the USB device in a laptop improves the signal for your phone - the laptop's wifi components are usually better than those in a smartphone so you set up a sub-network using the laptop as a relay station
As there is normally a power amplifier in the range extender, to make up for losses in initial transmission, it may be possible to build a device that would take the incoming signal, amplify this, and retransmit a stronger signal than the original
As any amplification adds noise to the original signal, and this is acceptable for Audio Transmission where human ears are quite forgiving, with data transmission the noise can result in damage to the data, so high quality, (and cost), amplification would be essential
I bought some of these range extender boosters on eBay for $10-15 and they did improve my home wifi. I could use an ethernet cable connection and had to enter an IP number to access my router. I guess you can't do that with a public wifi.They probably have some way of preventing access.
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