SouthPark
Newbie level 6
Hi all. While there are lots of articles explaining OFDM signals, I'm having trouble trying to find information (on the internet) about how each OFDMA mobile phone starts off its communication with a mobile base station.
That is, if 3 mobile phones near 1 mobile phone base station is trying to call out at the same time, then what happens in terms of :
What frequencies (sub-carrier frequencies) are used?
What channels are used so that the mobile base station can handle those call-outs at the same time?
When 3 mobile phone want to let a base station know that these phones are active (ie connect to the base station), then how do they know which frequencies to use in order to all talk to the base station at the same time without clashing or conflicting with each other? That is, how does each of those three mobile phone indicate its own presence at the same time? Do they have their own specially assigned communication frequencies to begin with so that one mobile phone doesn't clash with another one?
If anyone can direct me to some good reading material to help me understand many-user to base-station communications protocol for OFDM-type systems, then that would be really really appreciated. Thanks to all in advance!
That is, if 3 mobile phones near 1 mobile phone base station is trying to call out at the same time, then what happens in terms of :
What frequencies (sub-carrier frequencies) are used?
What channels are used so that the mobile base station can handle those call-outs at the same time?
When 3 mobile phone want to let a base station know that these phones are active (ie connect to the base station), then how do they know which frequencies to use in order to all talk to the base station at the same time without clashing or conflicting with each other? That is, how does each of those three mobile phone indicate its own presence at the same time? Do they have their own specially assigned communication frequencies to begin with so that one mobile phone doesn't clash with another one?
If anyone can direct me to some good reading material to help me understand many-user to base-station communications protocol for OFDM-type systems, then that would be really really appreciated. Thanks to all in advance!