A compact wideband polygonal patch antenna with enhanced bandwidth for X-, Ku-, and K-band applications

A compact wideband antenna is presented, employing a polygonal radiating patch with five segments excited through a tapered microstrip feedline. The proposed antenna is simulated on a Rogers RT/Duroid 5880 substrate and operates over a wide frequency range of 9.6–20.6 GHz, achieving a simulated fractional bandwidth of approximately 72.9%. This wideband response is primarily attributed to the use of a partial ground plane and a rectangular strip, which enhance impedance matching across multiple resonant modes. The simulated −10 dB impedance bandwidth spans three regions: 9.6–12 GHz (X-band), 12–18 GHz (Ku-band), and 18– 20 GHz (K-band). The design achieves a peak gain of 5.0 dBi and an average radiation efficiency of 75%. Owing to its compact profile, wide impedance bandwidth, and stable radiation performance, the antenna is suitable for wideband and multi-standard wireless communication applications.