This paper introduces concept, simulation and measurement results for a broadband dual-polarized stacked microstrip antenna with pin- and edge-feed for 5G applications in Ka-band. The design approaches take several requirements into account that are decisively for next generation 5G base stations. Dual-polarization for doubling link capacity, a large bandwidth for high data throughput as well as array compatibility are main issues. Especially the combination of these requirements makes the antenna design fastidiously. Techniques for bandwidth enhancement and dual-polarized feeding are elucidated. The realization is carried out in standard multilayer printed circuit board technology. The proof-of-concept shows that both antenna types reach measured -10 dB relative bandwidths between 12.8% and 16.4% with measured gains in mainbeam direction between 6.3 dBi and 7.1 dBi at 28 GHz.