Letter download query method in BeiDou communication system, system, and related apparatus

A first terminal, comprising:

• one or more memories configured to store computer program code comprising computer instructions;
• and
• one or more processors coupled to the one or more memories and configured to execute the computer instructions to cause the first terminal to:
• receive a first letter;
• send a letter download query request packet to a satellite network device, wherein the letter download query request packet requests downloading first content of a letter from one or more second terminals to the first terminal, wherein the letter download query request packet comprises a message identifier (ID) field, wherein the message ID field indicates a first letter ID of the first letter, and wherein the first letter ID instructs the satellite network device to delete the first letter;
• receive a second letter from the one or more second terminals;
• and
• receive a letter download query result packet from the satellite network device, wherein the letter download query result packet comprises a letter content field and a second letter ID field, the letter content field indicates second content of the second letter, wherein the second letter ID field indicates an ID of the second letter, and wherein the second letter ID is arranged after the first letter ID in sequence.

A chip system, used in a terminal and comprising:

• an interface circuit configured to receive code instructions and transmit the code instructions;
• and
• a processing circuit coupled to the interface circuit and configured receive the code instructions, wherein the processing circuit is configured to:
• receive a first letter;
• send a letter download query request packet to a satellite network device, wherein the letter download query request packet requests downloading first content of a letter from one or more second terminals to the first terminal, wherein the letter download query request packet comprises a message identifier (ID) field, wherein the message ID field indicates a first letter ID of the first letter, and wherein the first letter ID instructs the satellite network device to delete the first letter;
• receive a second letter from the one or more second terminals;
• and
• receive a letter download query result packet from the satellite network device, wherein the letter download query result packet comprises a letter content field and a second letter ID field, the letter content field indicates second content of the second letter, wherein the second letter ID field indicates an ID of the second letter, and wherein the second letter ID is arranged after the first letter ID in sequence.