LimeADPD
Lime Microsystems fully open source solution for PA linearisation based on adaptive digital pre-distortion (ADPD), delivered as FPGA IP and host software.
Power amplifiers (PA) always exhibit some degree of non-linearity and higher linearity products tend to be much more expensive. The Lime Adaptive Digital Pre-Distortion (ADPD) core allows stringent transmitter specifications to be met using a lower cost PA, by correcting the non-linear operation. In the case of radio frequency (RF) PAs, linearisation also improves power efficiency and subsequently reduces the running cost of the wireless infrastructure.
Considering the PA performance for a given air interface, adjacent channel power ratio (ACPR) and error vector magnitude (EVM) are the key considerations to provide support for sophisticated modulation schemes, multi-carrier signals, and high modulation bandwidths.
Open source
Lime Microsystems adaptive digital pre-distortion solution for PA linearisation is fully open source. The FPGA RTL and host software sources can be found on GitHub. For in-depth technical details, please see the documentation.
Supported hardware
LimeADPD is supported on the LimeSDR X3 board, which is installed in the LimeNET 2.0 and LimeNET Mini 2.0 integrated systems.