Improving bandwidth of rectangular microstrip antenna

[u/Parking-Break-170]

Guys so I'm building a rectangular microstrip antenna in HFSS for mmwave applications. Resonance at around 28 GHz. I am getting vswr<2 bandwidth of around 1.5GHz. How can i improve this. It's just a simple inset fed microstrip line. Please give me some resources or tips to learn on increasing impedance bandwidth

[u/sswblue]

There are articles on the subject. Slots were mentioned, but you can also cut the corners.