Transmitter with pre-distortion module, a method thereof
View Patent ↗Aspects of the disclosure provide a transmitter that includes a pre-distortion module and a phase controller. The pre-distortion module is configured to receive a first digital value and generate a first pre-distorted digital value based on the first digital value and a corresponding angle. The first digital value is a combination of an in-phase component and a quadrature component of a signal for transmission. The phase controller is configured to control an amplifier to drive a current according to the first pre-distorted digital value and phase information in relation to the first digital value during a first phase range of a carrier signal determined at least partially based on the angle.
1. A transmitter comprising:
a pre-distortion module configured to (i) receive a first digital value, and generate a first pre-distorted digital value based on the first digital value and a corresponding distortion angle, the first digital value being a first combination of an in-phase component and a quadrature component of a signal for transmission, and (ii) receive a second digital value, and generate a second pre-distorted digital value based on the second digital value and the corresponding distortion angle, the second digital value being a second combination of the in-phase component and the quadrature component of the signal for transmission; and
a phase controller, coupled to the pre-distortion module and an amplifier, configured to (a) control the amplifier to drive a current according to the first pre-distorted digital value and phase information in relation to the first digital value, during a first phase range of a carrier signal determined at least partially based on the corresponding distortion angle, and (b) control the amplifier to drive the current according to the second pre-distorted digital value and phase information in relation to the second digital value, during a second phase range of the carrier signal determined at least partially based on the corresponding distortion angle.
2. The transmitter of claim 1 , wherein the first digital value is an absolute value of a sum of the in-phase component and the quadrature component, and the second digital value is an absolute value of a difference between the in-phase component and the quadrature component.
3. The transmitter of claim 1 , further comprising:
a modem configured to generate the first digital value and the second digital value and provide the phase information in relation to the first digital value and the phase information in relation to the second digital value.
4. The transmitter of claim 2 , wherein the pre-distortion module is configured to calculate the first pre-distorted digital value and the second pre-distorted digital value as a function of the first digital value, the second digital value, and the corresponding distortion angle.
5. The transmitter of claim 1 , wherein the first phase range and the second phase range are within a radio frequency (RF) cycle.
6. The transmitter of claim 1 , wherein the pre-distortion module is configured to determine the corresponding distortion angle based on a look-up table.
7. The transmitter of claim 1 , wherein the pre-distortion module further comprises:
a first module configured to compensate for amplitude modulation to amplitude modulation (AMAM) distortion of the amplifier; and
a second module configured to compensate for amplitude modulation to phase modulation (AMPM) distortion of the amplifier.
8. The transmitter of claim 7 , wherein the amplifier is a radio frequency digital to analog converter (RFDAC).
9. A method comprising:
receiving a first digital value that is a first combination of an in-phase component and a quadrature component of a signal for transmission;
generating a first pre-distorted digital value based on the first digital value and a corresponding distortion angle;
receiving a second digital value that is a second combination of the in-phase component and the quadrature component of the signal for transmission;
generating a second pre-distorted digital value based on the second digital value and the corresponding distortion angle; and
controlling an amplifier (a) to drive a current according to the first pre-distorted digital value and phase information in relation to the first digital value in a first phase range of a carrier signal determined at least partially based on the corresponding distortion angle, and (b) to drive the current according to the second pre-distorted digital value and phase information in relation to the second digital value in a second phase range of the carrier signal determined at least partially based on the corresponding distortion angle.
10. The method of claim 9 , wherein the first digital value is an absolute value of a sum of the in-phase component and the quadrature component and the second digital value is an absolute value of a difference of the in-phase component and the quadrature component.
11. The method of claim 9 , where the first phase range and the second phase range are within a radio frequency (RF) cycle.
12. The method of claim 10 , further comprising:
calculating the first pre-distorted digital value as a function of the first digital value, the second digital value and the corresponding distortion angle; and
calculating the second pre-distorted digital value as a function of the first digital value, the second digital value and the corresponding distortion angle.
13. The method of claim 9 , further comprising:
determining the corresponding distortion angle based on a look-up table.
14. A wireless communication apparatus comprising:
an amplifier configured to drive a current to a load for transmission;
a pre-distortion module configured to (i) receive a first digital value and generate a first pre-distorted digital value based on the first digital value and a corresponding distortion angle, the first digital value being a first combination of an in-phase component and a quadrature component of a signal for transmission, and (ii) receive a second digital value and generate a second pre-distorted digital value based on the second digital value and the corresponding distortion angle, the second digital value being a second combination of the in-phase component and the quadrature component of the signal for transmission; and
a phase controller configured to (a) control the amplifier to drive the current according to the first pre-distorted digital value and phase information in relation to the first digital value, during a first phase range of a carrier signal determined at least partially based on the corresponding distortion angle, and (b) control the amplifier to drive the current according to the second pre-distorted digital value and phase information in relation to the second digital value, during a second phase range of the carrier signal determined at least partially based on the corresponding distortion angle.
15. The wireless communication apparatus of claim 14 , wherein the first digital value is an absolute value of a sum of the in-phase component and the quadrature component, and the second digital value is an absolute value of a difference between the in-phase component and the quadrature component.
16. The wireless communication apparatus of claim 14 , further comprising:
a modem configured to generate the first digital value and the second digital value and provide the phase information in relation to the first digital value and the phase information in relation to the second digital value.
17. The wireless communication apparatus of claim 15 , wherein the pre-distortion module is configured to calculate the first pre-distorted digital value and the second pre-distorted digital value as a function of the first digital value, the second digital value, and the corresponding distortion angle.
18. A system including a pre-distortion module coupled to a phase controller and an amplifier,
the pre-distortion module comprising:
an input interface configured to receive a first digital value and a second digital value; and
a circuit that is configured to generate a first pre-distorted digital value and a second pre-distorted digital value based on the first digital value, the second digital value and a corresponding distortion angle, wherein the first digital value is a first combination of an in-phase component and a quadrature component of a signal for transmission, and the second digital value is a second combination of the in-phase component and the quadrature component of the signal for transmission,
wherein the phase controller is configured to:
control the amplifier to drive a current according to the first pre-distorted digital value and phase information in relation to the first digital value, during a first phase range of a carrier signal determined based on the corresponding distortion angle; and
control the amplifier to drive the current according to the second pre-distorted digital value and phase information in relation to the second digital value, during a second phase range of the carrier signal determined based on the corresponding distortion angle.
19. The system of claim 18 , wherein the first digital value is an absolute value of a sum of the in-phase component and the quadrature component, and the second digital value is an absolute value of a difference between the in-phase component and the quadrature component.
20. The system of claim 18 , wherein the first pre-distorted digital value and the second pre-distorted digital value are generated based on following equations:
A PRE-DIST =A ′×cos φ+ B ′×sin φ
B PRE-DIST =B ′×cos φ− A ′×sin φ,
where A′ and B′ are generated based on the first digital value and the second digital value, φ denotes the corresponding distortion angle, and the first pre-distorted digital value and the second pre-distorted digital value are calculated based on A PRE-DIST , and B PRE-DIST .