In wireless communication, two pertinent performance metrics of data rate and bandwidth (BW) play a vital role. Wireless technology must be tuned to reach the most prevalent possible data rate. The usage of terahertz (THz) frequency has recently increased in various applications due to its non-ionizing characteristics. It is possible to attain a high data rate even in the terabits per second range using THz technology. The proposed antenna incorporates a photonic crystal (PhC) structure in addition to the THz technology to improve its performance. We propose a unique pie slotted patch (PSP) antenna using the simulation tool and explore the antenna attributes. We optimize the proposed PSP antenna in three cases by optimizing the PhC air hole shapes, lattice value, and dimensions. The triangular air hole PhC model shows that the best PSP antenna has a −71.35-dB return loss, a 1.0095 voltage standing wave ratio (VSWR), and a 9.87-dBi gain at a frequency of 2.04 THz. The proposed PSP antenna helps to deliver effective data rates in wireless communications and other various streams.