Method to demodulate amplitude offsets in a differential modulation system
AssigneeDelphi Technologies, Inc.
InventorsEric Dibiaso, Michael Hiatt, Glenn Walker
Life of this patent
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Abstract
Where the additional data throughput is added using an amplitude offset or a combination of phase and amplitude offset, the legacy differential demodulator does not recover the amplitude information. The present invention provides a method for demodulating amplitude offsets in a differential modulation system in order to recover the amplitude information. The demodulated amplitude information may be used to recover the additional Level 2 data transmitted as an amplitude offset or combination phase and amplitude offset in a differential multiple phase shift keying (D-MPSK) transmission, such as across adjacent OFDM symbols and/or adjacent frequency subcarriers.
Claims16
A method for demodulating amplitude offsets in a digital transmission system, comprising the steps of:
- a. receiving differential multiple phase shift keying (D-MPSK) modulated symbols with amplitude offset information;
- b. differentially demodulating D-MPSK modulated symbols;
- and
- c. demodulating Level 2 data encoded as amplitude offsets from D-MPSK modulated data.
An apparatus for demodulating amplitude offsets in a digital transmission system, said apparatus comprising:
- a. a digital transmission receiver adapted to detect differential multiple phase shift keying (D-MPSK) modulated symbols;
- and
- b. an amplitude offset detector.
An apparatus for modulating amplitude offsets in a digital transmission system, said apparatus comprising:
- a. a digital transmitter adapted to transmit differential multiple phase shift keying (D-MPSK) modulated symbols;
- and
- b. an amplitude offset encoder.
Dependencies are inferred from the claim text.