Developing step frequency train waveform for improved range resolution of Target in radar system
- April 26, 2022
- Posted by: RSIS
- Categories: Electronics & Communication Engineering, IJRIAS
International Journal of Research and Innovation in Applied Science (IJRIAS) | Volume VII, Issue III, March 2022 | ISSN 2454–6194
Developing step frequency train waveform for improved range resolution of Target in radar system
UGWU K. I. C, Eke J., Abonyi D. O
Enugu State University Of Science and Technology (Esut), Enugu
Abstract: This paper presents the developed step frequency model for high range resolution of target in radar system. The idea behind this research is to improve the detection capability of radar systems through improved step frequency model. This was achieved by transmitting a long linear frequency modulated (LFM) signals in a step-wise pattern, in which the centre frequency of the narrow bandwidth pulses of the transmitted signals are changed step by step and, are synthesized at the receiver to give a time profile characteristics of the target in view. The work was implemented using Matlab and the result of the simulation was carefully analyzed using the Ambiguity function for waveform analysis. It was observed that this waveform model really improved the range or detection index by 98% accuracy.
Keywords: Range, stepped frequency, transmitted signal, Ambiguity function, detection, reflected signal, waveform
I. INTRODUCTION
Based on several literatures by different authors on radar study and investigation, the waveform design and analysis [1] forms the important part of the radar design. When the radar transmits an electromagnetic signal to a target, the signal interacts with the target and then returns to the radar. The change in the properties of the returned signal reflects on the characteristics of the target. When the target is moving, the carrier frequency of the returned signal will be shifted due to Doppler Effect. The Doppler frequency shift can be used to determine the radial velocity of the moving target. If the target or any structure on the target is vibrating or rotating in addition to target translation, it will induce frequency modulation on the returned signal that generates sidebands about the target’s Doppler frequency [2]. However, a long pulse degrades range resolution. Hence, frequency or phase modulation of the signal is used to achieve a high range resolution when a long pulse is required. The capabilities of short-pulse and high range resolution radar are significant [3].
