Transmitter with reduced power consumption and increased linearity and dynamic range
View Patent ↗This application relates to an apparatus comprising a signal generator configured to generate a signal. The apparatus encompasses a predistortion unit configured to pre-distort the generated signal. The apparatus includes a pulse width modulating unit configured to modulate the pre-distorted signal into at least two signals. The apparatus comprises at least two amplifying units each configured to amplify one of the two modulated signals.
1. An apparatus comprising:
a signal generator configured to generate a signal;
a predistortion unit configured to pre-distort the generated signal;
a pulse width modulating unit configured to modulate the pre-distorted signal onto two signals, each being opposite phase shifted;
at least two amplifying units each configured to amplify one of the two modulated signals;
a combining unit configured to combine at least two amplified signals; and
a feedback loop path configured to correct the generated signal depending on a combined signal generated by the combining unit.
2. The apparatus according to claim 1 , wherein the signal generator is configured to generate a polar signal.
3. The apparatus according to claim 1 , wherein at least one amplifying unit is a switching power amplifier.
4. The apparatus according to claim 1 , wherein the predistortion unit is configured to determine a phase shift function depending on the generated signal.
5. The apparatus according to claim 1 , wherein the predistortion unit comprises a first determining unit configured to determine a duty cycle function depending on the generated signal.
6. The apparatus according to claim 1 , further comprising a pulse position modulating unit configured to process a phase component of the generated signal.
7. The apparatus according to claim 1 , wherein the feedback loop path comprises a converting unit configured for down converting the combined signal.
8. The apparatus according to claim 1 , wherein the feedback loop path comprises a processing unit configured to correct the generated signal depending on the down converted signal.
9. The apparatus according to claim 1 , wherein the feedback loop path comprises a down converting and error detecting unit.
10. The apparatus according to claim 1 , wherein the feedback loop path comprises an amplitude and/or phase correcting unit.
11. The apparatus according to claim 1 , wherein the feedback loop path comprises a phase shifting unit.
12. The apparatus according to claim 1 , wherein the feedback loop path comprises a phase correction unit.
13. The apparatus according to claim 5 , wherein the predistortion unit comprises a second determining unit configured to determine the phase shift function depending on the determined duty cycle function.
14. The apparatus according to claim 6 , wherein the pulse position modulating unit comprises a first mapping unit configured to map the phase component to at least one suitable function according to a chosen implementation of the pulse position modulating unit.
15. The apparatus according to claim 6 , wherein the pulse position modulating unit comprises a first up converting unit.
16. The apparatus according to claim 6 , wherein the pulse width modulating unit and the pulse position modulating unit are arranged as one pulse width pulse position modulating unit.
17. The apparatus according to claim 8 , wherein the processing unit comprises at least one of:
an envelope detecting unit; and
a phase detecting unit.
18. The apparatus according to claim 14 , wherein the pulse width modulating unit comprises a second mapping unit configured to map the phase shift function to at least one suitable function according to a chosen implementation of the pulse width modulating unit.
19. The apparatus according to claim 15 , wherein the pulse width modulating unit comprises a second up converting unit.
20. The apparatus according to claim 19 , wherein the pulse width modulating unit comprises a third up convening unit.
21. A method comprising:
generating a signal;
pre-distorting the generated signal;
pulse width modulating the pre-distorted signal onto at least into two signals, each being opposite phase shifted;
amplifying at least the two modulated signals;
combining at least two amplified signals; and
correcting the generated signal depending on the combined signal.
22. A non-transitory computer readable medium having a computer program stored thereon, the computer program comprising instructions operable to cause a processor to perform the steps of:
generating a signal;
pre-distorting the generated signal;
pulse width modulating the pre-distorted signal onto at least into two signals, each being opposite phase shifted;
amplifying at least the two modulated signals;
combining at least two amplified signals; and
correcting the generated signal depending on the combined signal.
23. A transmitter comprising an apparatus comprising:
a signal generator configured to generate a signal;
a predistortion unit configured to pre-distort the generated signal;
a pulse width modulating unit configured to modulate the pre-distorted signal onto at least two signals, each being opposite phase shifted;
at least two amplifying units each configured to amplify one of the two modulated signals;
a combining unit configured to combine at least two amplified signals; and
a feedback loop path configured to correct the generated signal depending on a combined signal generated by the combining unit.