Predistortion system with targeted spectrum emission for wireless communication

A method comprising:

• filtering, by an intermodulation distortion (IMD) filter module, a detected feedback signal (Yin) to generate a targeted filtered signal (Yout) by:
• generating, by a gain mask generating module of the IMD filter module, a gain mask based on at least one transmission measurement;
• applying, by a gain mask processing module of the IMD filter module, the gain mask to the detected feedback signal (Yin);
• generating, by a filter design generating module of the IMD filter module, a signal filter based on at least one transmission requirement:
• and
• generating, by a targeted filtered signal generating module of the IMD filter module, the targeted filtered signal (Yout) based on the signal filter;
• updating, by a digital pre-distortion (DPD) coefficient estimation module, signal generation coefficients based on comparing an input signal (Sin) with the targeted filtered signal (Yout);
• and
• generating, by a distortion compensation processing module, a pre-distorted signal (Uout) based on the input signal (Sin) using the updated signal generation coefficients.

A non-transitory computer-readable medium storing instructions therein which, when run on a processor, causes the processor to:

• filter a detected feedback signal (Yin) to generate a targeted filtered signal (Yout) by:
• generating a gain mask based on at least one transmission measurement;
• applying the gain mask to the detected feedback signal (Yin);
• generating a signal filter based on at least one transmission requirement;
• and
• generating the targeted filtered signal (Yout) based on the signal filter;
• update signal generation coefficients based on comparing an input signal (Sin) with the targeted filtered signal (Yout);
• and
• generate a pre-distorted signal (Uout) based on the input signal (Sin) using the updated signal generation coefficients.

A transmitter system comprising:

• a signal decomposition module configured to extract a low-frequency signal (S1o) and a high-frequency signal (Shi) from an input signal (Sin);
• a distortion compensation processing module configured to generate a pre-distorted low-frequency signal (U1o) and a pre-distorted high-frequency signal (Uhi) based on the low-frequency signal (S1o) and the high-frequency signal (Shi) using signal generation coefficients;
• a signal combining module configured to combine the pre-distorted low-frequency signal (U1o) and the pre-distorted high-frequency signal (Uhi);
• an intermodulation distortion (IMD) filter module configured to filter a detected low-frequency feedback signal (Y1o) to generate a targeted low-frequency filtered signal (Y1o’) and filter a detected high-frequency feedback signal (Yhi) to generate a targeted high-frequency filtered signal (Yhi’), the IMD filter module comprising a low-frequency IMD filter module and a high-frequency IMD filter module each comprising:
• a gain mask generating module configured to generate a gain mask based on at least one transmission measurement;
• a gain mask processing module configured to apply the gain mask to the detected high-frequency or low-frequency feedback signal (Y1o or Yhi);
• a filter design generating module configured to generate a signal filter based on at least one transmission requirement;
• and
• a targeted filtered signal generating module configured to generate the targeted high-frequency or low-frequency filtered signal (Y1o’ or Yhi’) based on the signal filter;
• and
• a signal characteristic estimation processing module configured to update the signal generation coefficients used by the distortion compensation processing module based on comparing the low-frequency signal (S1o) and the high-frequency signal (Shi) with the targeted low-frequency filtered signal (Y1o’) and the targeted high-frequency filtered signal (Yhi’).

A method comprising:

• extracting, by a signal decomposition module, a low-frequency signal (S1o) and a high-frequency signal (Shi) from an input signal (Sin);
• generating, by a distortion compensation processing module, a pre-distorted low-frequency signal (U1o) and a pre-distorted high-frequency signal (Uhi) based on the low-frequency signal (S1o) and the high-frequency signal (Shi) using signal generation coefficients;
• combining, by a signal combining module, the pre-distorted low-frequency signal (U1o) and the pre-distorted high-frequency signal (Uhi);
• filtering, by an intermodulation distortion (IMD) filter module, a detected low-frequency feedback signal (Y1o) to generate a targeted low-frequency filtered signal (Y1o’) and filter a detected high-frequency feedback signal (Yhi) to generate a targeted high-frequency filtered signal (Yhi’) by:
• generating, by a gain mask generating module of the IMD filter module, a low-frequency gain mask and a high-frequency gain mask based on at least one transmission measurement;
• applying, by a gain mask processing module of the IMD filter module, the low-frequency and high-frequency gain masks to the detected low-frequency feedback signal (Y1o) and the detected high-frequency feedback signal (Yhi), respectively;
• generating, by a filter design generating module of the IMD filter module, a low-frequency signal filter and a high-frequency signal filter based on at least one transmission requirement;
• and
• generating, by a targeted filtered signal generating module of the IMD filter module, the targeted low-frequency filtered signal (Y1o’) based on the low-frequency signal filter and the targeted high-frequency filtered signal (Yhi’) based on the high-frequency signal filter;
• and
• updating, by a signal characteristic estimation processing module, the signal generation coefficients used by the distortion compensation processing module based on comparing the low-frequency signal (S1o) and the high-frequency signal (Shi) with the targeted low-frequency filtered signal (Y1o’) and the targeted high-frequency filtered signal (Yhi’).

A non-transitory computer-readable medium storing instructions therein which, when run on a processor, causes the processor to:

• extract a low-frequency signal (S1o) and a high-frequency signal (Shi) from an input signal (Sin);
• generate a pre-distorted low-frequency signal (U1o) and a pre-distorted high-frequency signal (Uhi) based on the low-frequency signal (S1o) and the high-frequency signal (Shi) using signal generation coefficients;
• combine the pre-distorted low-frequency signal (U1o) and the pre-distorted high-frequency signal (Uhi);
• filter a detected low-frequency feedback signal (Y1o) to generate a targeted low-frequency filtered signal (Y1o’) and filter a detected high-frequency feedback signal (Yhi) to generate a targeted high-frequency filtered signal (Yhi’) by:
• generating a low-frequency gain mask and a high-frequency gain mask based on at least one transmission measurement;
• applying the low-frequency and high-frequency gain masks to the detected low-frequency feedback signal (Y1o) and the detected high-frequency feedback signal (Yhi), respectively;
• generating a low-frequency signal filter and a high-frequency signal filter based on at least one transmission requirement;
• and
• generating the targeted low-frequency filtered signal (Y1o’) based on the low-frequency signal filter and the targeted high-frequency filtered signal (Yhi’) based on the high-frequency signal filter;
• and
• update the signal generation coefficients used by the distortion compensation processing module based on comparing the low-frequency signal (S1o) and the high-frequency signal (Shi) with the targeted low-frequency filtered signal (Y1o’ ) and the targeted high-frequency filtered signal (Yhi’).