Performance Trade-off between Communication and Sensing Based on AFDM Parameter Adjustment

Affine frequency division multiplexing (AFDM) is a promising waveform due to its excellent performance in doubly dispersive channels. Compared with OFDM, AFDM has two more adjustable parameters with better flexibility. By analyzing the diversity gain of AFDM system and deducing the Cramér-Rao lower bounds (CRLB) of unknown parameters, this paper studies the influence of the parameter $c_{1}$ of AFDM on the bit error rate (BER) and parameter estimation. In addition, an adaptive waveform approach is proposed to adapt to different communication and sensing requirements based on AFDM parameter $c_{1}$ and a demand factor. The simulation results confirm the validity of our analysis, which shows that $c_{1}$ can be adjusted according to the demand factor to achieve the optimal performance compromise.