Advanced on using digital predistortion in radio station for new generations of wireless systems
Résumé
The wireless telecommunications industry is currently experiencing the deployment of numerous standards, making it possible to meet the growing requirements of users in terms of quality of service, high data-rate and security of transmissions as well as density of connection relays. The introduction of these new standards represents the addition of a new hardware layers whose environmental impact adds to that of previous generations. In this context, reducing the energy required for radiocommunication is a necessity, especially in base stations, which account for 73% of mobile network consumption In this context, new waveforms based on multicarrier modulation become widely popular and used intensively in recent radio communication architectures. Their properties in term of dynamic spectrum adjustment make OFDM (Orthogonal Frequency-Division Multiplexing) and derivatives modulation a promising technology for recent and future radio systems. However, these signals are sensitive to the power amplifier nonlinearities because of their high fluctuations. Digital Pre-Distortion (DPD) is now widely used to linearize RF amplifiers, which consumes the major part of the base station power, and attemps to resolve the linearity/efficiency tradeoff in LTE/5G signals. In literature, many DPD schemes have been developed and implemented in recent communication standard. The result is significant reduction of energy consumption in base station. In this presentation, I will present recent academic and industrial results and challenges for the field of linearization using Digital Pre-Distortion in wideband applications. I focused the presentation on new evolution of linearization methods based on parameter estimation in off-line and on-line architectures. Implementation and recent industrial project are also presented with different scenarios like aeronautical application, WiFi signals and LTE/5G applications.