Trajectory modification technique for polar transmitter
View Patent ↗This application discussed trajectory modification techniques for polar transmission architectures. In an example, a method can include receiving a first sample, determining an absolute phase angle change between the first sample and a third sample, and if the first angle change is greater than a threshold phase angle, adjusting phase information of a second sample to provide a modified second sample such that a trajectory associated with the first sample, the modified second sample and the third sample passes through an origin. In an example, the second sample can be received prior to receiving the first sample, and the third sample can be received prior to receiving the second sample.
1. A signed polar transmitter comprising:
a radio frequency digital to analog converter (RFDAC) configured to receive phase modulation information and processed amplitude information and to provide a radio frequency transmission signal for broadcast using an antenna;
a phase lock loop (PLL) configured to receive processed phase information and to provide the phase modulation information; and
a compensation circuit configured to receive phase transmit information and amplitude transmit information for three consecutive trajectory samples of an original trajectory path, referenced to an origin, of the radio frequency transmission signal, and to modify the phase transmit information of a single, time-wise middle sample of the three consecutive trajectory samples to generate the processed phase transmit information,
wherein the phase transmit information is modified to match the phase transmit information of one of the other trajectory samples of the three consecutive trajectory samples; and
wherein a modified trajectory path associated with the processed phase transmit information is closer to the origin than the original trajectory path.
2. The signed polar transmitter of claim 1 , wherein the compensation circuit is configured to change a polarity of the amplitude information of the time-wise middle sample to generate the processed amplitude information.
3. The signed polar transmitter of claim 1 , wherein the compensation circuit is configured to set the phase transmit information of the time-wise middle sample equal to the phase transmit information of a first sample of the three consecutive trajectory samples, wherein the time-wise middle sample is received prior to receiving the first sample.
4. The signed polar transmitter of claim 1 , wherein the compensation circuit is configured to set the phase transmit information of the time-wise middle sample equal to the phase transmit information of a first sample of the three consecutive trajectory samples plus about 180 degrees, wherein the time-wise middle sample is received prior to receiving the first sample.
5. The signed polar transmitter of claim 1 , wherein the compensation circuit is configured to set the phase transmit information of the time-wise middle equal to the phase transmit information of a third sample of the three consecutive trajectory samples, wherein the time-wise middle sample is received prior to receiving a first sample of the three consecutive trajectory samples, and the third sample is received prior to receiving the time-wise middle sample.
6. The signed polar transmitter of claim 1 , wherein the compensation circuit is configured to set the phase transmit information of the time-wise middle equal to the phase transmit information of a third sample of the three consecutive trajectory samples plus about 180 degrees, wherein the time-wise middle sample is received prior to receiving a first sample of the three consecutive trajectory samples, and the third sample is received prior to receiving the time-wise middle sample.
7. The signed polar transmitter of claim 1 , wherein the compensation circuit is configured to not change a polarity of the amplitude information of the time-wise middle sample to generate the processed amplitude information.
8. At least one non-transitory machine readable storage medium comprising a plurality of instructions for modifying transmission sample trajectory of a signed polar transmitter that when executed by a computing device cause the computing device to:
receive phase modulation information and processed amplitude information at a radio frequency digital to analog converter (RFDAC) of the signed polar transmitter;
provide a radio frequency transmission signal from the RFDAC;
broadcast the radio frequency transmission signal using an antenna;
receive processed phase information at a phase lock loop (PLL) of the signed polar transmitter;
provide the phase modulation information from the PLL;
receive phase transmit information and amplitude transmit information for three consecutive trajectory samples of an original trajectory path, referenced to an origin, of the radio frequency transmission signal at a compensation circuit of the signed polar transmitter;
modify the phase transmit information of a single, time-wise middle sample of the three consecutive trajectory samples to generate the processed phase transmit information using the compensation circuit configured to,
wherein the phase transmit information is modified to match the phase transmit information of one of the other trajectory samples of the three consecutive trajectory samples; and
wherein a modified trajectory path associated with the processed phase transmit information is closer to the origin than the original trajectory path.
9. The at least one non-transitory machine readable medium as recited in claim 8 , further comprising instructions that when executed by the computing device cause the computing device to change a polarity of the amplitude information of the time-wise middle sample to generate the processed amplitude information using the compensation circuit.
10. The at least one non-transitory machine readable medium as recited in claim 8 , further comprising instructions that when executed by the computing device cause the computing device to set the phase transmit information of the time-wise middle sample equal to the phase transmit information of a first sample of the three consecutive trajectory samples using the compensation circuit, wherein the time-wise middle sample is received prior to receiving the first sample.
11. The at least one non-transitory machine readable medium as recited in claim 8 , further comprising instructions that when executed by the computing device cause the computing device to set the phase transmit information of the time-wise middle sample equal to the phase transmit information of a first sample of the three consecutive trajectory samples plus about 180 degrees using the compensation circuit, wherein the time-wise middle sample is received prior to receiving the first sample.
12. The at least one non-transitory machine readable medium as recited in claim 8 , further comprising instructions that when executed by the computing device cause the computing device to set the phase transmit information of the time-wise middle equal to the phase transmit information of a third sample of the three consecutive trajectory samples using the compensation circuit, wherein the time-wise middle sample is received prior to receiving a first sample of the three consecutive trajectory samples, and the third sample is received prior to receiving the time-wise middle sample.
13. The at least one non-transitory machine readable medium as recited in claim 8 , further comprising instructions that when executed by the computing device cause the computing device to set the phase transmit information of the time-wise middle equal to the phase transmit information of a third sample of the three consecutive trajectory samples plus about 180 degrees using the compensation circuit, wherein the time-wise middle sample is received prior to receiving a first sample of the three consecutive trajectory samples, and the third sample is received prior to receiving the time-wise middle sample.
14. The at least one non-transitory machine readable medium as recited in claim 8 , further comprising instructions that when executed by the computing device cause the computing device to not change a polarity of the amplitude information of the time-wise middle sample to generate the processed amplitude information.