very small aperture terminals (T1VSAT) were developed for
NASA by the Harris Corporation to work with the on-board processor
and prove that small terminals could be used with spot beams
in a single-hop, full mesh network. Using a 1.2-meter antenna,
these terminals provided a full 1.8 Mbps on-demand service
at data rates from 64 Kbps to 1.8 Mbps for voice, video and
They operated using time division multiple access (TDMA)
in a demand-assigned multiple access (DAMA) scheme. Communications
to the spacecraft occurred at a burst rate of 27.5 Mbps (uncoded)
and 13.75 Mbps (coded). The spacecraft burst traffic at 110
Mbps (uncoded) and 55 Mbps (coded) to these terminals.
Maximum EIRP: 60/66 dBW. Maximum G/T: 16/22
dB/K. Modulation: 5 MSK for uplink and downlink. Nominal
BER: 5x10-7(10 dB fade margin).