Memory predistortion in bandwidth limited envelope tracking
US9973370B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 6, 2017 |
| Grant date | May 15, 2018 |
| Priority date | — |
| Expiry date | Jun 6, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F2201/3224
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An apparatus compensates nonlinearities in envelope tracking (ET) used in a mobile device by limiting a bandwidth of an envelope signal representing an envelope of an input baseband signal to be less than a bandwidth of tracker circuitry, generating a scaled replica of an output signal of the tracker circuitry based on the bandwidth-limited envelope signal, and generating a model distortion signal based on the scaled replica and the input baseband signal, where the model distortion signal emulates ET linearity degradation. The apparatus is further configured to generate an output baseband signal based on the scaled replica, the model distortion signal, and the input baseband signal, where the output baseband signal is pre-distorted relative to the input baseband signal according to the scaled replica, the model distortion signal, and the input baseband signal to compensate for degradations in transmit signal quality due to ET nonlinearities.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.