Systems and methods for cable headend transmission

1. A segmented system for cable transmission, comprising:

a plurality of paths, each of the plurality of paths comprising:

an up-tilt circuit configured to receive an input digital signal that has a flat spectrum and generate an up-tilted digital signal that has an up-tilted spectrum;

a digital-to-analog converter configured to receive the up-tilted digital signal and to provide an analog signal; and

a power amplifier configured to receive the analog signal and amplify the analog signal for cable transmission, wherein the analog signal is not further up-tilted in an analog domain between the digital-to-analog converter and the power amplifier.

2. The system of claim 1 , further comprising a pre-driver configured to amplify the analog signal from a first power level to a second power level.

3. The system of claim 2 , wherein the pre-driver consumes a small amount of power.

4. The system of claim 1 , wherein the up-tilt circuit is configured to generate the up-tilted digital signal by up-tilting the input digital signal with a total required up-tilt.

5. The system of claim 4 , wherein each path of the plurality of paths terminates at a cable plant, and the total required up-tilt is determined according to a frequency-dependent signal loss at the cable plant and frequency roll-off at the digital-to-analog converter.

6. The system of claim 2 , wherein the second power level meets a power required by the power amplifier.

7. The system of claim 1 , wherein each of the plurality of paths further comprises a digital pre-distortion (DPD) circuit configured to apply a pre-distortion to the up-tilted digital signal.

8. The system of claim 7 , wherein the DPD circuit receives a feedback signal from an output of the power amplifier and is configured to modify the pre-distortion to the up-tilted digital signal in response to the feedback signal.

9. The system of claim 2 , wherein the pre-driver is a 1.4 Watt or less pre-driver.

10. A device for cable transmission, comprising:

an up-tilt circuit configured to receive an input digital signal that has a flat spectrum and generate an up-tilted digital signal that has an up-tilted spectrum;

a digital pre-distortion (DPD) circuit configured to apply a pre-distortion to the up-tilted digital signal;

a digital-to-analog converter configured to receive the up-tilted digital signal and to provide an analog signal;

an analog filter configured to receive the analog signal, compensate for a roll off characteristic of the digital-to-analog converter, and provide a filtered signal, wherein the analog filter has an insertion loss of less than 2.5 dB and the up-tilt circuit and the analog filter provide a combined up-tilt response for an entire transmission path of the device;

a pre-driver configured to amplify the filtered signal and provide a pre-driven signal, the pre-driver having a gain of less than 20 dB; and

a power amplifier configured to receive the pre-driven signal and amplify the pre-driven signal for transmission via a cable.

11. The device of claim 10 , wherein the pre-driver consumes a small amount of power.

12. The device of claim 11 , wherein the pre-driver consumes 1.5 Watts or less of power.

13. The device of claim 10 , wherein the up-tilt circuit provides 20 dB of up-tilt in a digital domain.

14. The device of claim 13 , further comprising:

a thermal compensation system comprising a temperature sensor and a thermal control circuit configured to adjust a bias current of the digital-to-analog converter in response to temperature.

15. The device of claim 10 , wherein the DPD circuit receives a feedback signal from an output of the power amplifier and is configured to modify the pre-distortion to the up-tilted digital signal.