Optimal coded sequence design for radar using fractional oppositional particle swarm optimization

Polyphase coded radar signals is one of the most important and usually used in MIMO Radar systems. Polyphase coded radar signals with good orthogonal properties having low autocorrelation and a low crosscorrelation property is a nonlinear multivariable optimization problem. The proposed technique yield polyphase waveforms with orthogonal properties which effectively removes the interference issues faced by radars and also help in attaining high radar resolution. The oppositional concept is included in the initial population selection in the PSO algorithm and fractional calculus is used for modifying the velocity updation equation in PSO. Peak Sidelobe Ratio (PSLR) and Integrated Energy Sidelobe ratio (ISLR) of the polyphase waveforms are incorporated in the fitness function defined for the PSO. The experimental analysis based on different phases, different sequence lengths, different code set and different cost function are carried out. In all cases, the proposed technique has achieved good results.