Exhibit B Necessary Bandwidth

0150-EX-ST-2002 Text Documents

Mobile Satellite Ventures Subsidiary LLC

2002-04-17ELS_55364

Exhibit B: Explanation of Necessary Bandwidths

The following table shows the terminal, data rate, modulation type, baud (modulation rate), and
corresponding necessary bandwidth for each type of terminal to be used in the MT demonstrations. All data
transmitted in these demonstrations will be digital. BPSK modulation is used for the 600-bps data rate
transmissions and QPSK or offset-QPSK (OQPSK) is used for all other transmissions. As can be found in
numerous references on the topic, the bandwidth efficiency for BPSK-modulated emissions is 1 bit/s/Hz,
while that for QPSK-modulated emissions is 2 bits/s/Hz.

Transmissions from the AERO/H, WorldPhone Marine, and Saturn-B terminals will use concatenated
(220,200) Reed-Solomon and 7/8-rateViterbi FEC codes that will increase the coded data rate. The baud
will be half the coded data rate, due to QPSK bandwidth efficiency. The HPA will be driven into saturation
during transmission, expanding the necessary emission bandwidth approximately 20% above the baud.

Terminal Type Data Rate Coding Rate Digital Baud Necessary
(bps) (chips/s) Modulation Bandwidth (Hz)
AERO/I 600 Uncoded Aviation BPSK 600 600
AERO/I 10500 Uncoded Aviation QPSK 5250 5250
AERO/H 256000 322000 OQPSK 161000 193000
Saturn-Bm/Bt2 512000 644000 OQPSK 322000 386000
WorldPhone 16000 20100 OQPSK 10100 12100
Marine w/TPU

Document Created: 2002-04-18 07:12:36
Document Modified: 2002-04-18 07:12:36

© 2024 FCC.report
This site is not affiliated with or endorsed by the FCC