This paper presents channel propagation measurements and analysis of the channel characteristics of millimeter wave (mmWave) transmission for urban cellular communication systems, in particular in the promising 28 GHz band. For channel propagation analysis, the urban measurement campaign was conducted with a synchronously spherical scanning 28 GHz channel sounder system, from which omni-like channel measurements are obtained for channel modeling. From the measurements, we analyze the spatio-temporal channel characteristics such as multipath delay, angular statistics, and pathloss. The clustering analysis has been done including its power distribution. Then, a set of millimeter wave radio propagation parameters is presented, and the corresponding channel models based on the 3GPP spatial channel model (SCM) are also described.