In addition to the above-mentioned research work, in this Special Issue, nine novel antennas and filter designs have been presented for various wireless and 5G communication technologies. [PERSON] et al. proposed a quasi-Yagi antenna with resistor-loaded arms to obtain a filtering response with four radiation nulls (contribution 10). The embedded resistor-loaded arms achieved two additional radiation nulls caused by reverse currents and absorbed the unwanted out-of-band resonant points brought by themselves. The director close to the driver provided a resonant point and a radiation null caused by opposite currents between the driver and the director. Compared with other filtering quasi-Yagi antennas, the proposed design could achieve a filtering response with a compact size along the end-fire direction. A balun-integrated prototype covering the 5G band N78 (3.3-3.8 GHz) showed a 10 dB impedance-matching bandwidth of 22.9% (3.21-4.04 GHz), four radiation nulls, and a peak gain of 4.73 dBi. Another design introduced a high-gain UWB Vivaldi antenna loaded with artificial electromagnetic material, suitable for ground-penetrating radar (GPR) systems (contribution 11). The artificial electromagnetic units affected the antenna radiation waves by changing the refractive index to enhance the antenna's directivity. Moreover, four Vivaldi units were arranged into a horn-shaped array, and each of the two units were orthogonally fed to realize dual polarization. A compact-size UHF RFID tag antenna using slot apertures and capacitive gaps with large reads was ranged for outdoor localization applications (contribution 12). The effects of capacitive slots and gaps on the impedance matching between conventional industrial chips and a designed RFID antenna were investigated. Alternatively, a multi-frequency antenna loaded with a ring structure has been presented (contribution 13). The patch consists of resonator structures, and the ground plate consists of a bottom metal strip and three ring-shaped metals with regular cuts to form a defective ground structure to be operated for 5G NR (FR1, 0.45-3 GHz), 4 GLTE (1.6265-1.6605 GHz), Personal Communication System (1.85-1.99 GHz), Universal Mobile Telecommunications System (1.92-2.176 GHz), WiMAX (2.5-2.69 GHz), and other communications frequency bands. Similarly, another design introduced a multiband planar inverted L-C implantable antenna with SAR values within the safety limits with maximum allowable input power (contribution 14). The proposed antenna operates at low power levels and supports an energy-efficient solution. Additionally, the SAR values are within the safety limits, with a maximum allowable input power (8.43 mW (1 g) and 47.5 mW (10 g) at 402.5 MHz; 12.85 mW (1 g) and 47.8 mW (10 g) at 2.45 GHz; and 11 mW (1 g) and 50.5 mW (10 g) at 2.95 GHz). A wideband graded effective refractive index (GRIN) dielectric lens antenna for 5G mm-wave band applications has been presented (contribution 15). The inhomogeneous holes in the dielectric plate are perforated to provide GRIN in the proposed lens. A UWB monopole antenna with an octagonal patch was fed with a 50 \(\Omega\) line and with a triple band notch feature (contribution 16). In this design, an L-shaped stub, an inverted C-shaped slot, and a pair of U-shaped resonating structures are introduced into the design, which allows the antenna to generate three band notches at 3.22-3.83 GHz, 4.49-5.05 GHz, and 7.49-8.02 GHz, corresponding to the WiMAX band, Indian national satellite (INSAT) band, and X-band satellite frequencies, respectively. [PERSON] et al. presented a miniaturized high-performance flower-shaped radiator (FSR) (contribution 17). The antenna can be used for modern smartphones' connectivity with the sub-6 GHz frequency spectrum of modern 5G mobile communication applications. Furthermore, an antenna pair for mobile terminals using a type of coupling feed planar antenna and a wide band coupling suppression has been proposed (contribution 18).