zigbee is a ieee802.15.4 wireless protocol used to transfer data up to 75mts
I doubt the above statement..
According to digi
XBee
• Indoor/Urban: up to 133’ (40 m)
• Outdoor line-of-sight: up to 400’ (120 m)
• Transmit Power: 2 mW (3 dBm)
• Receiver Sensitivity: -96 dBm
XBee-PRO
• Indoor/Urban: up to 300’ (90 m), 200' (60
m) for International variant
• Outdoor line-of-sight: up to 1 mile (1600
m), 2500' (750 m) for International variant
• Transmit Power: 50mW (17dBm), 10mW
(10dBm) for International variant
• Receiver Sensitivity: -102 dBm