A method for communication includes transmitting a first uplink message from a first remote node (200, 300, 400) to a central node (100) in a wireless communication system according to a first frequency hopping scheme, and transmitting a second uplink message from a second remote node to the central node in the wireless communication system according to a second frequency hopping scheme, different from the first scheme. Both the first and the second uplink messages are received and processed at the central node.