Highly focussed beampattern synthesis in FDA-MIMO radar with multicarrier transmission

Multicarrier technology is widely used for improving the performance of beampattern synthesis in frequency diverse array multiple-input and multiple-output (FDA-MIMO) Radar. However, how to use multicarrier technology to achieve highly focussed beampattern synthesis is still an open problem. To this end, the authors first establish the system model of FDA-MIMO radar with multicarrier transmission and analyse the parameters influencing beampattern synthesis by Cramér–Rao lower bound derivation. It can be recognised that frequency increments and multicarrier distribution are key parameters hindering highly focussed beampattern synthesis. On top of the investigation, a simple yet effective Multidimensional Non-linear Frequency Component, named multidimensional frequency components (MNFC), is proposed for forming a highly focussed beam. Specifically, MNFC is a two-dimension frequency component for FDA-MIMO radar. The first dimension is the frequency increment weighted by the Dynamic Taylor Window Function that effectively decouples the joint-range-angle beampattern. The second dimension is a non-linear multicarrier weighted by Log with a Linear Coefficient for further optimising dot-shaped beampatterns for target indication with high precision. Finally, numerical simulations and comparative experiments are performed to validate the superiority of the MNFC in beampattern synthesis.