Detection Performance Analysis of MIMO Radar Dual Channels LFM and NLFM Waveforms in The Presence of Clutter

The waveforms orthogonality concept of the Multiple-Input Multiple-Output (MIMO) radar model is designed by using Doppler Division Multiple Access (DDMA) to transmit dual channel waveforms. Linear Frequency Modulation (LFM) waveform is used for the first channel, while a Nonlinear Frequency Modulation (NLFM) waveform is used for the second channel. The two channels are orthogonal to each which allows the dual transmitted channels to be separated at the receiver. The results obtained in this paper show that the Dual Channels waveforms mitigate the effect of different models for correlated clutter and uncorrelated clutter drones' detection, enhance the side lobe level, reduce the range-Doppler coupling of ambiguity function permitting for better target separation and identification, less exposed to interference from other operating radars and electronic countermeasures. This approach also improves target detectability, especially for small and stealthy targets due to the use of NLFM waveform in one channel, as well as the enhancement of the Doppler tolerance due to using LFM waveform in the other channel. The results obtained show that DDMA MIMO radar receiver sensitivity is enhanced for small Radar Cross Section (RCS) targets (drones), and has a significant impact on the target characteristics, the operating environment, and the desired performance in terms of range resolution, Doppler sensitivity, clutter rejection, and interference rejection, when using Dual Channels waveforms as shown in the obtained results.