Complex sentence: For military communications satellites, the ITU assigned X-band uplink frequency band (for sending modulated signals) is from 7.9 to 8.4 GHz, and the ITU assigned downlink frequency band (for receiving signals) is from 7.25 to 7.75 GHz.
Split into simpler sentences: For military communications satellites, the ITU has assigned the X-band uplink frequency band (for sending modulated signals) as from 7.9 to 8.4 GHz. The ITU-assigned downlink frequency band (for receiving signals) is from 7.25 to 7.75 GHz.