UHF modem which is used while the satellite is in orbit, is an AstroDev Li-100. This modem has extensive flight heritage.
The UHF antenna is selected as a turnstile dipole in order to keep omni-directionality and circular polarization. The antennae will be wrapped during launch in order to fit into the launcher pod. Some 20 minutes after orbit injection the antennae will be released by melting the holding wires by heating resistors. Below you see a picture of the satellite back plate, with the antennae wrapped around the turnstiles. After release, the antennae will unfold and spread along the diagonals of the plate.
The Iridium modem, used right after the re-entry black-out phase tos end the scientific payload data to the Iridium constellation is a COTS Iridium 9523 modem.