Modulation and coding adjustment based on slant range characteristics for satellite downlinks

A method of identifying a modulation and coding format according to slant range distances, the method comprising:

• associating each of a plurality of modulation and coding formats with a different set of slant range distances;
• identifying a slant range distance between a low earth orbit satellite and a receiving terminal;
• determining a selected one of the different sets of slant range distances including the identified slant range distance;
• and
• identifying a selected one of the plurality of modulation and coding formats associated with the selected set of slant range distances.

A method for adapting a modulation and coding format according to slant range distances, the method comprising:

• associating each of a plurality of modulation and coding formats with a different set of slant range distances;
• identifying time periods associated with each of at least a subset of the different sets of slant range distances;
• and
• associating each of the identified time periods with a selected one of the modulation and coding formats.

A terminal for transmitting data identifying a modulation and coding format, the ground terminal comprising:

• a memory unit configured to store an association between each of a plurality of modulation and coding formats with a different set of slant range distances;
• a scheduler unit, communicatively coupled with the memory unit, and configured to:
• calculate slant range distances associated with a low earth orbit satellite over time;
• utilize the calculated slant range distances to identify time periods each associated with selected ones of the different sets of slant range distances;
• and
• associate each of the identified time periods with a selected one of the modulation and coding formats;
• and
• a transmitter unit, communicatively coupled with the scheduler unit, and configured to transmit information comprising an identification of the modulation and coding formats and associated time periods.