In this paper, a miniaturized wideband coplanar waveguide (CPW) fed modified semi-Vivaldi antenna has been proposed for Ku-band applications. An exceptional semi-Vivaldi profile with a dimension of 30 � 32 � 1.529 mm3 has been developed and optimized to reduce the size and cost. In addition, instead of using the conventional exponential profile, this semi-Vivaldi structure is partitioned, utilizing linear segments to regulate impedance matching across the entire frequency range. To improve the radiation characteristics such as efficiency, reflection coefficient, directivity, bandwidth, VSWR, and gain, different circular and corrugated slots have been used. For further optimization and improvement, circular gratings have been used, which improve the overall gain and efficiency. The semi-Vivaldi antenna is developed, simulated, and evaluated using CST Microwave studio (MWS) suite. For Ku-band communication, the ideal band is from 12 GHz to 18 GHz. With a maximum efficiency of 78, this semi-Vivaldi antenna provides a broad operating frequency range of 10.2 - 21.5 GHz. Finally, it is observed from the simulated results that the presented semi-Vivaldi antenna would be a possibility for Ku-band applications. © 2022 IEEE.