All the members of IEEE802 family include the MAC (Media Access Control) sub-layer and Physical Layer of the OSI Model of the network.
In the wireless network, IEEE802.11 is used which adopt the CSMA/CA in the MAC The main point of CSMA/CA is that, before the sender beginning to send signal, it should listen to the channel, to be exactly, whether some signal is being transmitted right now, if there is, it should wait a period of time to avoid collision.
The simplest situation that hidden terminal prolem could happen: node B can communicate with node A and node C, however A and C don't know the existence of each other for some reason because they didn't find out any signal that is being transmitted. So, collision will happen when both A and C are trying to send message to B.
In order to solve the problem RTS (Request To Send) /CTS (Clear To Send) is used. If A wants to send message to B, it should send RTS to B first, if B received the RTS from A, and if it permits A to send message it will send CTS, at this time CTS can also be received by C, in this situation, C knows that B is prepared to received a message from someone others and restrains itself not disturbing others.
However, RTS/CTS method can not solve the hidden terminal problem perfectly for several reasons.
1. RTS and CTS from different node may also collision
2. CTS may not be received
3. RTS/CTS can also be influent by the condition of channel