QO-100 WB Bandplan

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The QO-100 Wideband Transponder Digital ATV operating guidelines and bandplan were revised in March 2020 and can be found here: QO-100 Bandplan V2.0.

The bandplan can also be represented graphically:

V2.0 Graphic Final 2.JPG

Recommended Frequencies

Narrow DATV transmissions should be confined to the “Narrow DATV” section, but may use the “Wide and Narrow DATV” section if the Narrow DATV section is fully occupied.

The recommended Narrow DATV frequencies in the new bandplan are all now at 250 kHz spacing, with alternate channels (*.250 and *.750) designated for 333 kS and 250 kS.

Bandplan V2.0 Table.JPG

Power Levels

During March 2020, the beacon bandwidth was reduced to leave more bandwidth for users on the transponder. However, to maintain the data rate, the FEC was increased from 2/3 to 4/5. This meant that to leave the same signal margin for signal decoding, the beacon power density had to be increased by just over 1 dB.

What this means is that user signal power densities (for QPSK) should now be limited to 1 dB lower than the beacon. This can clearly be seen on the spectrum monitor, and the overpower indication trigger limit has been adjusted. For signals of 333 kS and below (only), it is acceptable to exceed this marging if 8PSK, 16 APSK or 32 APSK modes are being used.