A method of operating a communication system to communicate with a plurality of wireless devices comprises determining a first shape for a first wireless signal to reach the plurality of wireless devices, transmitting the first wireless signal encoded with a first communication to the plurality of wireless devices, receiving an acknowledgment from a first device of the plurality of wireless devices indicating that the first device received and decoded the first communication, determining a second shape for a second wireless signal to reach a second device of the plurality of wireless devices, and transmitting the second wireless signal encoded with error correction information for the first communication to the second device of the plurality of wireless devices.