t's assume that the gNB and/or 306 Chapter 3 Cross-polarized elements Co-polarized elements Figure 3.7 3D base station antenna model [4]. the UE each has a 2D planar antenna subarray comprising Ms X Ns antenna elements, where Ns denotes the number of columns and Ms is the number of antenna elements with the same polarization in each column (see Fig. 3.7). The antenna elements are uniformly spaced with a center-to-center spacing of dh and dv in the horizontal and vertical directions, respectively. The Ms X Ns elements may either be single polarized or dual polarized. A uniform rectangu- lar array is formed comprising MXN antenna panels where M is the number of panels in a column and N is the number of panels in a row. Antenna panels are uniformly spaced with a center-to-center spacing of dH and dv in the horizontal and vertical directions, respec- tively. The 3GPP 3D channel model allows modeling 2D planar antenna arrays. The antenna elements can either be linearly polarized or cross polarized, as shown in Fig. 3.7. In this regard, the model represents a compromise between practicality and precision as it does not include the mutual coupling effect as well as different propagation effects of horizon- tally and vertically polarized waves [7]. For each antenna element, the general form of antenna element horizontal radiation pattern can be specified as AE.H(O) = - min ( where - 180° O < 180°, denotes the horizontal 3 dB beam-width, and the parameter am is the maximum side-lobe level attenuation. The general form of antenna element vertical radiation pattern is specified as Ae,v( = - min (12 where 180° O V 180°, A3dB denotes the verti- cal 3 dB beam-width, and Otilt is the tilt angle. It must be noted that 0=0 points to the zenith and O =90° points to the horizon. The combined vertical and horizontal antenna New Radio Access Physical Layer Aspects (Part 1) 307 element pattern is then given as A(A, - - where A(A, 0) is the relative antenna gain (dB) of an antenna element in the direction (0,0) [4,7,24]. The above conc