Patent ID: 11924016
Assignee: MITSUBISHI ELECTRIC CORPORATION
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A method for transmitting a data stream from a transmitting device to a receiving device, the data stream comprising m data sub-streams, m ≥4, said method comprising:
encoding the data sub-streams with respective polar codes, such as to produce m polar-encoded data sub-streams,
modulating the m polar-encoded data sub-streams onto symbols of a multilevel modulation comprising m levels defining 2m different symbols in a complex plane, according to a predetermined labeling function Z which bijectively associates a symbol to a set c1, . . . , cm of m bits from respective polar-encoded data sub-streams, such that successive sets of m bits from respective polar-encoded data sub-streams are converted into successive symbols forming a symbol stream,
transmitting the symbol stream to the receiving device,
wherein the 2m symbols of the multilevel modulation are distributed in the complex plane such that they are regularly spaced along the real axis and the complex axis by a spacing factor K,
wherein the predetermined labeling function Z is such that:

Φ(Z)<1.7m×(0.0425×m−0.06)

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