[theamk]

Unfortunately Shannon–Hartley theorem is very harsh on mesh networks.

900MHz in US is 902-928 MHz, 26 MHz wide channel. The usual SNR ratio range is 0-40 dB. This corresponds to total bandwith over entire band of 26 to 172 Mbit/sec -- depending on the range. Let's be generous and say 100 Mbit/sec.

You are not going to get any sort of beanforming from the mobile pocket-held device, so your collision domain is going to be everyone around you. Say you are in the park, and there are 24 people around you, and you are all routing packets for each other, so each packet is transmitted twice before leaving the collision domain. In this case, single person's ideal, best case bandwith is 2 Mbit/sec.

In practice, you are not going to get anywhere close to 100% efficiency, so I'd expect internet speeds significantly less that 1 Mbit/sec. This is going to be very painful.