iPhone 4 and download speed via WiFi

Last night I did a small test in which I tried to see what the download speed is from the Internet through the WiFi network of the iPhone 4. For the test I connected to an ad hoc network made with a WiFi network card that shared the Internet from a network card connected to RDS. I have a subscription of 39 lei (the one with the speed of up to 100mbits), with fiber optic connection, from switch to switch, and network cable to the switch. From the tests done, it appears that I should have a download speed of at least 10mbits/1MB from the servers connected to the RDS metropolitan network and in reality it is, but I did not manage to get more than 1MB even though the network I am connected to supports up to at 54mbps.

I tried to copy something to the phone with WinSCP, but the speed did not exceed 700KB/s even though I was connected to a network that supports up to 54mbps. I don't know what exactly produces this "cooking" of the speed, but since I have an iPhone I have not been able to copy anything to it via WiFi with more than a few hundred KB and I have not been able to download anything from the Internet at a higher speed of 1MB. What speeds did you achieve when downloading from the Internet or copying to your phone via WiFi (regardless of which iPhone model you have)?