Retransmission of selected PAM-modulated message portions in 5G/6G

A wireless receiver configured to:

• receive a first message comprising message elements, each message element modulated according to a modulation scheme, the modulation scheme comprising a plurality of predetermined amplitude levels and an I-branch signal multiplexed with a Q-branch signal, each of the I-branch and Q-branch signals modulated according to one of the predetermined amplitude levels respectively;
• determine that the first message is corrupted;
• measure, for each message element of the first message, an I-branch amplitude value and a Q-branch amplitude value;
• calculate, for each message element of the first message, a first difference between the I-branch amplitude value and the closest predetermined amplitude level, and a second difference between the Q-branch amplitude value and the closest predetermined amplitude level;
• determine, for each message element of the first message, a modulation quality according to the first and second differences;
• select one or more of the message elements having modulation quality lower than a predetermined limit;
• and
• determine a portion of the first message, the portion containing all of the selected message elements.

Non-transitory computer-readable media in a base station of a wireless network comprising instructions that when executed by a computing environment cause a method to be performed, the method comprising:

• transmitting, to a user node of the wireless network, a first message;
• receiving, from the user node, a retransmit request specifying a portion of the first message;
• and
• retransmitting, to the user node, the specified portion of the first message.