One of the known strategies used by modern radars to attain good range resolution is frequency stepping. The key benefit of this method is that radar's actual instantaneous bandwidth is fairly small in comparison to its entire processing bandwidth. This permits waveforms with extremely broad overall bandwidth to be sent, allowing for great range resolution without the requirement for the expensive technology required to provide wide instantaneous bandwidth. Unwanted peaks known as grating lobes may arise in the autocorrelation function of uniform frequency stepped pulse trains. When appropriately designed stepped frequency waveforms are used, we can minimise grating lobes by employing a method that allows us to suppress grating lobes below a specific threshold and replacing linear FM (LFM) pulses of bandwidth B in place of fixed frequency pulses. Uniform PRI (Pulse Repetition Interval) Stepped Linear Frequency Modulation (SLFM) is considered here, as well as non-uniform PRI (increasing and decreasing order) SLFM with various lengths. The ambiguity function, which influences the performance of the radar, is used to calculate the peak side lobe ratio and Integrated side lobe ratio. This paper proposed a new model for SLFM (Stepped Linear Frequency Modulation) signals to eliminate side lobes.