Spacecraft --- Space Station --- Communication

The ISS must be able to communicate with flight controllers on the ground daily and, astronauts must be able to communicate with each other within the ISS and when conducting spacewalks outside the station.

Talking with the Ground
NASA's Mission Control in Houston will send signals to a 60-foot radio antenna at White Sands Test Facility. White Sands will relay the signals to a pair of Tracking and Data Relay satellites. The satellites will relay the signals to the U.S. portion of the ISS and/or the space shuttle if it is attached.
During the early phase, signals will be sent through the Russian Space Agency's communications system of ground stations and/or satellites.
The ISS has two systems for communicating with the ground:
S-band - voice, commands, telemetry and data files
Ku-band (high bandwidth) - video and transfer of two-way data files

Talking Within the ISS and to Spacewalkers
The Internal Audio Subsystem (IAS) will provide intercom, telephone and alarm system communications within the ISS's pressurized modules.
The IAS will also connect with the following:
- Ultra-High Frequency (UHF), to talk with spacewalkers
- External connectors, to talk with a docked space shuttle
- Russian segment's audio system

Structure of the ISS Propulsion Communication Navigation Power Computer Resupply Escape Research in the ISS