Here's a thought experiment. Remember, there's only one channel.
Let's say you have 100 meshtastic nodes in a residential valley. And you have 1 meshtastic repeater up on a mountain overlooking the valley (or it could be on a radio tower or water tower, say).
So it's clear that most of these nodes won't see each other because terrain, housing, trees, etc.
But it is possible that the repeater may have clear line of sight to most of them. And that's where the hidden node problem lies.
And adding more nodes and more repeaters is not going to help. The problem is either solved by increasing the number of channels (hence the sdr angle) or by time division multiplexing the single channel and coordinating who can talk at what time. The first is easy. The second is much harder.
Let's say you have 100 meshtastic nodes in a residential valley. And you have 1 meshtastic repeater up on a mountain overlooking the valley (or it could be on a radio tower or water tower, say).
So it's clear that most of these nodes won't see each other because terrain, housing, trees, etc.
But it is possible that the repeater may have clear line of sight to most of them. And that's where the hidden node problem lies.
And adding more nodes and more repeaters is not going to help. The problem is either solved by increasing the number of channels (hence the sdr angle) or by time division multiplexing the single channel and coordinating who can talk at what time. The first is easy. The second is much harder.