I have an Airport Express (AE) configured as base station with two airport express units acting as repeaters. All AE's are first generation with latest software updates installed. Configuration:
Airport Express 1 creating wireless network 2.4 GHz
AE repeater 2 configured as "extend wireless network" connects to AE 1
AE repeater 3 configured as "extend wireless network" connects to AE 2
All AE's display green light. AE number 2 does repeat and transmit the wifi signal, but it does in fact not repeat the wifi signal. If I take any mobile device near AE number 3, it does not connect to this AE.
Any ideas what could be wrong here?
... I suspected this limitation but Apple does not make mention of this in their documentation.
If another extended Wi-Fi base station ➋ is placed between the primary Wi-Fi base station ➊ and the extended Wi-Fi base station ➌, the extended Wi-Fi base station ➌ will not allow clients to join it. All extended Wi-Fi base stations must be in direct range of the primary Wi-Fi base station
It is also untrue that "everytime you repeat a signal in my configuration, the throughput speed is cut in half. " This was true for WDS but not with an 802.11n "extended" network. The throughput is reduced but the effect is much less than 50%.
The fact that you have a lot of range to conver including concrete walls means that you will have challenges with "extending" a network wirelessly. Wireless signals will be attenuated by such structures. If you can find a way to create a "roaming network" your troubles will be over.