Amplitude-variation encoding for high-density 5G/6G modulation
Modulation schemes for 5G/6G are disclosed that include amplitude-variation modulation states as well as prior-art constant-amplitude states. In an amplitude-variation scheme, the amplitude of the transmitted signal is varied during each message element instead of being held constant throughout the message element. The variation may be a stepwise amplitude switch between two amplitude levels, or a linear amplitude ramp, according to the modulation scheme. The amplitude-variations provide many additional modulation states, thereby providing higher bits per message element, so that messages can be made shorter, with no decrease in message content. In addition, methods to mitigate frequency shifts, sideband generation, and signal spill-over to adjacent subcarriers are provided. With amplitude-variation modulation, the network throughput can be increased and expenses can be decreased, according to some embodiments.
1. Non-transitory computer-readable media in a wireless transmitter, the media containing instructions that when executed in a computing environment cause a method to be performed, the method comprising:
transmitting a message element comprising a wireless message, the message element comprising one resource element, the resource element comprising one symbol-time in time and one subcarrier in frequency, the message element modulated according to a modulation scheme, the modulation scheme comprising a plurality of modulation states, each modulation state comprising amplitude modulation according to a plurality of predetermined amplitude levels, wherein:
each modulation state comprises a first amplitude level followed by a second amplitude level;
the amplitude modulation of the message element varies, during the symbol-time of the message element, from the first amplitude level to the second amplitude level;
calculating, according to a difference between the first and second amplitude levels, a frequency shift;
calculating a corrected frequency by subtracting, from a transmission frequency of the subcarrier, the calculated frequency shift; and
transmitting the message element at the corrected frequency.
2. The media of claim 1 wherein
the message element comprises a first portion followed by a second portion, the first portion amplitude modulated according to a first amplitude level of the modulation scheme, and the second portion amplitude modulated according to a second amplitude level of the modulation scheme, the second amplitude level different from the first amplitude level.
3. The media of claim 2 , wherein the first portion comprises a first half of the symbol-time and the second portion comprises a second half of the symbol-time.
4. The media of claim 1 , wherein the amplitude modulation varies linearly from a first amplitude level of the modulation scheme to a second amplitude level of the modulation scheme during the symbol-time.
5. The media of claim 1 , wherein the first amplitude level and the second amplitude level have the same sign.
6. The media of claim 1 , wherein the first amplitude level and the second amplitude level have opposite signs.
7. The media of claim 1 , the method further comprising:
transmitting, proximate to the wireless message, a demodulation reference comprising one or more reference resource elements, each reference resource element modulated according to a predetermined modulation state the modulation scheme.
8. Non-transitory computer-readable media in a wireless transmitter, the media containing instructions that when executed in a computing environment cause a method to be performed, the method comprising:
transmitting a message element comprising a wireless message, the message element comprising one resource element, the resource element comprising one symbol-time in time and one subcarrier in frequency, the message element modulated according to a modulation scheme, the modulation scheme comprising a plurality of modulation states, each modulation state comprising amplitude modulation according to a plurality of predetermined amplitude levels, wherein:
each modulation state comprises a first amplitude level followed by a second amplitude level;
the amplitude modulation of the message element varies, during the symbol-time of the message element, from the first amplitude level to the second amplitude level;
transmitting, proximate to the wireless message, a demodulation reference comprising one or more reference resource elements, each reference resource element modulated according to a predetermined modulation state the modulation scheme; and
providing a gap before and after each reference resource element;
wherein each gap comprises a resource element with zero transmission therein.
9. A method for demodulating a wireless message comprising:
receiving a message element comprising the message;
determining a first amplitude value of the message element;
determining a second amplitude value of the message element, the second amplitude value different from the first amplitude value;
determining a first code or number according to the first amplitude value and a second code or number according to the second amplitude value; and
providing the first code or number and the second code or number to a processor configured for interpreting the message;
calculating, according to a difference between the first amplitude value and the second amplitude value, a spill-over comprising energy or amplitude generated in an adjacent subcarrier, the adjacent subcarrier adjacent to the subcarrier of the message element; and
subtracting, from an adjacent message element in the adjacent subcarrier, the calculated spill-over.
10. The method of claim 9 , wherein:
the message element comprises a resource element, the resource element comprising one symbol-time and one subcarrier;
the message element comprises a first portion of the symbol-time followed by a second portion of the symbol time; and
the message element is amplitude modulated according to the first amplitude value during the first portion, and amplitude modulated according to the second amplitude value during the second portion.
11. The method of claim 10 , wherein the first portion comprises a first half of the symbol-time and the second portion comprises a second half of the symbol-time.
12. The method of claim 9 , wherein:
the message element comprises a resource element, the resource element comprising one symbol-time and one subcarrier; and
the message element amplitude varies linearly from the first amplitude value to the second amplitude value during the symbol-time.
13. A method for demodulating a wireless message comprising:
receiving a message element comprising the message;
determining a first amplitude value of the message element;
determining a second amplitude value of the message element, the second amplitude value different from the first amplitude value;
determining a first code or number according to the first amplitude value and a second code or number according to the second amplitude value; and
providing the first code or number and the second code or number to a processor configured for interpreting the message;
receiving a demodulation reference proximate to the message;
determining, from the demodulation reference, at least two predetermined amplitude levels;
recording, in a calibration set, the at least two predetermined amplitude levels; and
assigning, to each of the at least two predetermined amplitude levels, a distinct code or number.