It depends.
The reason a repeater losses bandwidth is because the user of the repeater must make two wireless hops to reach the wireless router.
[wireless router]<-- wireless -->[repeater]<-- wireless -->[wireless client]
All the wireless stations are using the same wireless frequency. But only two wireless stations can be transmitting at any given time. So whenever the wireless client is talking to the repeater, the repeater can’t be talking w/ the wireless router, and vice versa. In effect, all communications is serialized, it never happens in parallel (as would be the case w/ wire). As a result, the effective bandwidth is HALVED for the wireless client. Add more repeaters and it’s HALVED again and again.
The reason I said it depends is because this same problem *does* affect any wireless access point.
[wireless router]<-- wireless -->[wireless clients (two of them)]
In this case, whenever BOTH wireless clients are trying to communicate w/ the wireless router at the same time, one of them must wait for the other to complete its transmission before the other can begin. IOW, it’s the exact same issue as when using a repeater!
A repeater is just a specific example of a more general problem. The fact everyone is using the same frequency means everyone is in contention for that frequency. It’s like having everyone using walkie-talkies on the same frequency. It’s a party line and ppl have to take turns. And the more ppl you add, the more it slows communications throughput.
The only reason we speak of the problem more readily w/ repeaters is that a repeater is GUARANTEED to cause a bandwidth loss with even a single wireless client, whereas in the second case it would require at least two wireless clients, AND, only when attempting to access the wireless access point at the exact same time (e.g., two large, concurrent downloads). For many ppl, the latter is not something that either happens to them (they are the lone wireless client), or it does so only rarely, or when it does, they don’t notice the impact over short-lived transmissions. But it’s always there lurking as a potential problem.
Hopefully that explanation should stir some ideas about how to avoid the problem. One way is to create YOUR OWN repeater. Nothing says you can’t chain a wireless ethernet bridge to another wireless access point (that’s all a repeater is), each using DIFFERENT frequencies, and thus preserve your bandwidth.
[wireless router]<-- wireless -->[wireless ethernet bridge]<-- wire -->[wireless access point]<-- wireless -->[wireless client]
Yes, it adds more “bulk” to the solution, but it’s still a repeater, and now each side of the repeater can communicate at the same time.