Wifi uses spread spectrum technology which can have difficulties decoding signals when two identical signals are received with a small time delay. Wimax uses OFDMA which divides data across multiple subcarriers, making it more robust to signal interference and easier to implement MIMO. While Wifi struggles at distances over a few hundred meters, Wimax can provide throughput of up to 2.5Gbps at 20km and is better suited for mining sites due to its ability to handle high signal reflection and absorption. Key considerations for a Wimax implementation include data throughput needs, quality of service requirements, and allowing suppliers flexibility in choosing parameters to optimize performance within bandwidth limits.