Tomlinson-harashima precoding with non-overlapping dynamic modulation coding subsets
A Tomlinson-Harashima Precoding (THP) transmitter transmits data modulated by non-overlapping Dynamic Modulation Coding (DMC) to a receiver. In order to enable the receiver to differentiate between the different modulations of the DMC, a novel non-overlapping DMC is used. The constellations of the non-overlapping DMC are selected such that the result of the modulo operation of the THP maintains the signal levels, belonging to the different constellations, separated.
1. A Tomlinson-Harashima Precoding transmitter, comprising:
a signal generator configured to produce non-overlapping Dynamic Modulation Coding signals comprising: a first Pulse-Amplitude Modulation constellation of M levels (PAM-M), and a second Pulse-Amplitude Modulation constellation of N levels (PAM-N), wherein M>N; wherein the meaning of producing Dynamic Modulation Coding is that a receiver expects to receive either PAM-M or PAM-N signals, and not just PAM-M signals or just PAM-N signals;
wherein the PAM-M and PAM-N constellations have different levels without any overlap thereof; and
wherein the Tomlinson-Harashima Precoding transmitter uses modulo K*M, where K is an integer equal to or greater than two; and wherein the result of the modulo K*M operation applied to the PAM-M and PAM-N constellations maintains the signal levels belonging to the different constellations without any overlap thereof.
2. The Tomlinson-Harashima Precoding transmitter of claim 1 , wherein the non-overlapping Dynamic Modulation Coding utilizes odd levels for highest constellation, and non-overlapping even levels for other constellations.
3. The Tomlinson-Harashima Precoding transmitter of claim 1 , wherein the non-overlapping Dynamic Modulation Coding comprises the following constellations: PAM-16 {−15, −13, −11, −9, −7, −5, −3, −1, 1, 3, 5, 7, 9, 11, 13, 15}, and PAM-8 {−14, −10, −6, −2, 2, 6, 10, 14}.
4. The Tomlinson-Harashima Precoding transmitter of claim 3 , wherein the non-overlapping Dynamic Modulation Coding further comprises the following constellations: PAM-4 {−12, −4, 4, 12}, and PAM-2 {−8, 8}.
5. The Tomlinson-Harashima Precoding transmitter of claim 1 , wherein the non-overlapping Dynamic Modulation Coding comprises the following constellations: PAM-8 {−7, −5, −3, −1, 1, 3, 5, 7,}, and PAM-4 {−6, −2, 2, 6}.
6. The Tomlinson-Harashima Precoding transmitter of claim 5 , wherein the non-overlapping Dynamic Modulation Coding further comprises the constellation: PAM-2 {−4, 4}.
7. A Tomlinson-Harashima Precoding transmitter, comprising:
a signal generator configured to produce non-overlapping Dynamic Modulation Coding signals comprising: a first Pulse-Amplitude Modulation constellation of M levels (PAM-M), and a second Pulse-Amplitude Modulation constellation of N levels (PAM-N); wherein M>N, and the PAM-M and PAM-N constellations have different levels without any overlap thereof; and wherein the meaning of producing Dynamic Modulation Coding is that a receiver expects to receive either PAM-M or PAM-N signals, and not just PAM-M signals or just PAM-N signals; and
a Tomlinson-Harashima Precoder configured to receive the non-overlapping Dynamic Modulation Coding signals and a compensation signal, and to output a modulo K*M result, where K is an integer equal to or greater than two; wherein the result of the modulo K*M operation applied to the PAM-M and PAM-N constellations maintains the signal levels belonging to the different constellations separated.
8. The Tomlinson-Harashima Precoding transmitter of claim 7 , wherein the non-overlapping Dynamic Modulation Coding utilizes odd levels for highest constellation, and non-overlapping even levels for other constellations.
9. The Tomlinson-Harashima Precoding transmitter of claim 7 , wherein the non-overlapping Dynamic Modulation Coding comprises the following constellations: PAM-16 {−15, −13, −11, −9, −7, −5, −3, −1, 1, 3, 5, 7, 9, 11, 13, 15}, and PAM-8 {−14, −10, −6, −2, 2, 6, 10, 14}.
10. The Tomlinson-Harashima Precoding transmitter of claim 9 , wherein the non-overlapping Dynamic Modulation Coding further comprises the following constellations: PAM-4 {−12, −4, 4, 12}, and PAM-2 {−8, 8}.
11. The Tomlinson-Harashima Precoding transmitter of claim 7 , wherein the non-overlapping Dynamic Modulation Coding comprises the following constellations: PAM-8 {−7, −5, −3, −1, 1, 3, 5, 7,}, and PAM-4 {−6, −2, 2, 6}.
12. The Tomlinson-Harashima Precoding transmitter of claim 11 , wherein the non-overlapping Dynamic Modulation Coding further comprises the constellation: PAM-2 {−4, 4}.