# Review of Recent Phased Arrays for Millimeter-Wave Wireless Communication
## 2 Millimeter-Wave Antenna Array for 5G Communication
### Millimeter-Wave Antenna Arrays for 5G Mobile Terminals
#### 2.1.3 Single-Layer Phased-Array Antennas for 5G Mobile Terminals
The proposed beam-steering phased-array has achieved an angular scanning range of 0\({}^{\circ}\) to 60\({}^{\circ}\) at 28 GHz, as shown in Figure 13g. The gain variation in the angular scanning range of \(\pm\)60\({}^{\circ}\) is symmetrical with 15.6 dBi as peak gain. Two-dimensional (2D) radiation plots for various scanning angles of the proposed phased array are shown in Figure 13g. [PERSON] et al. also presented the effect of the user's body on the gain and impedance matching of the proposed phased array, as illustrated in Figure 14a,b. The analysis of the user's body effects on the proposed 16-element phased arrays shows that it can achieve a reasonable gain of at least 6.9 dBi, even with the user's body effects. Table 1 categorizes the performance of recent phased arrays for the 5G mobile terminal devices discussed in this section. A performance comparison has been made based on the beam-scanning capability, peak gain, and array elements of various phased arrays. Figure 14: (**a**) Effects of user’s body on the proposed eight-element phased array with different beam-scanning angles positioned on the left side of mobile terminal. (**b**) User body effects on the eight-element phased array located along the right edge of mobile terminal at different beam-scanning angles. (Redrawn from [41])  
Figure 13: (**a**) Different views of mobile terminal design. (**b**) Photograph of mobile terminal with proposed phased-array antennas. (**c**) Design of proposed eight-element antenna array. (**d**) Block diagram of eight-element beam-steering antenna array. (**e**) Block diagram description of 28-GHz front-end RFIC chip. (**f**) Simulated and measured input reflection coefficients and isolation between array elements. (**g**) 2D radiation plots at different scanning angles (Redrawn from [41]). \begin{table}
\begin{tabular}{l c c c c c c c c} \hline \hline
**Ref \#** & **No. of Subarrays** & **Elements Per Subarray** & **f\({}_{6}\) (GHz)** & **BW (GHz)** & **Beam-Scanning (deg)** & **Peak Gain (dBi)** & **Substrate** & **Array Position** \\ \hline
[10] & 2 & \(1\times 16\) & 27.9 & =1 & \(\pm 70^{\circ}\) & 10.5 & Multilayer-PCB & Top and Bottom \\
[46] & 4 & \(1\times 16\) & 28 & - & \(\pm 80^{\circ}\) & - & Multilayer-FR4 & Four Corners \\
[49] & 3 & \(1\times 8\) & 21.5 & =1 & \(\pm 90^{\circ}\) & 12.5 & Nucle N9000 & Top \\
[48] & 1 & \(1\times 8\) & 28 & \(>\)1 & \(\pm 70^{\circ}\) & 12 & N900 PTFE & Top \\
[50] & 3 & \(1\times 8\) & 28 & =2 & \(\pm 73^{\circ}\), \(\pm 128^{\circ}\), \(\pm 20^{\circ}\) & 12.5 & Nucle N9000 & Top \\
[41] & 2 & \(1\times 8\) & 28 & \(>\)2.5 & \(<\)60\({}^{\circ}\) & 15.6 & Metallic casing & Left and Right \\
[42] & 1 & \(1\times 8\) & 28 & \(>\)8 & \(\pm 90^{\circ}\) & 12 & Taocnic RF-30 & Top \\
[47] & 3 & \(1,1\times 4,1\) & 36 & \(>\)2 & - & 11 & Multilayer-PCB & Top (Mid + Corners) \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Performance variation of various phased arrays for 5G mobile terminals.