# Antenna-on-Chip for Millimeter Wave Applications Using CMOS Process Technology
## 2 Structure, Mechanism, and Design
\[\epsilon_{\text{eff}}=\frac{\epsilon_{r}+1}{2}+\frac{\epsilon_{r}-1}{2}\Big{[} 1+12\frac{h}{W}\Big{]}^{-\frac{1}{2}} \tag{2}\]0 The geometry of the designed monopole patch antenna and M1 layer AMC. \[\epsilon_{\text{eff}}=\frac{\epsilon_{r}+1}{2}+\frac{\epsilon_{r}-1}{2}\Big{[} 1+12\frac{h}{W}\Big{]}^{-\frac{1}{2}} \tag{2}\]1 The geometry of the proposed antenna-on-chip. \[\epsilon_{\text{eff}}=\frac{\epsilon_{r}+1}{2}+\frac{\epsilon_{r}-1}{2}\Big{[} 1+12\frac{h}{W}\Big{]}^{-\frac{1}{2}} \tag{2}\]2 The geometry of AMC in the M1 layer. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Parameter** & **Value (\(\mu\)m)** & **Parameter** & **Value (\(\mu\)m)** \\ \hline L & 1200 & W & 1200 \\ L\({}_{1}\) & 50 & W\({}_{1}\) & 450 \\ L\({}_{2}\) & 400 & W\({}_{2}\) & 15 \\ L\({}_{3}\) & 350 & W\({}_{3}\) & 90 \\ L\({}_{4}\) & 140 & W\({}_{4}\) & 20 \\ L\({}_{5}\) & 110 & W\({}_{5}\) & 250 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Detailed value of the proposed antenna. The parameters of the antenna structure designed in this paper are analyzed to obtain the maximum radiation gain. As shown in Figure 8, the length of the feeder transmission line of this antenna structure is analyzed, and the detailed size and bandwidth are shown in Table 3. When the feed-in line length L\({}_{3}\) is 200 \(\upmu\)m, the frequency bandwidth is 35 GHz when the reflection coefficient of the frequency band is lower than \(-\)10 dB, but the frequency bandwidth is lower than \(-\)10 dB. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Parameter** & **Value (\(\upmu\)m)** & **Parameter** & **Value (\(\upmu\)m)** \\ \hline L\({}_{5}\) & 10 & W\({}_{6}\) & 70 \\ L\({}_{6}\) & 90 & W\({}_{7}\) & 10 \\ L\({}_{7}\) & 10 & W\({}_{8}\) & 40 \\ L\({}_{8}\) & 70 & & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: The detailed value of the proposed AMC. Figure 6: Simulated S11 of the antenna. Figure 7: Simulated gain of the antenna. the minimum reflection coefficient is only \(-13\) dB. Moreover, when the length L\({}_{3}\) of the feed line is increased to \(350\)\(\upmu\)m, the bandwidth is \(11\) GHz when the reflection coefficient of the frequency band is lower than \(-10\) dB, and the minimum value of the reflection coefficient reaches \(-20\) dB. Finally, when the length L\({}_{3}\) of the feed-in line increases to \(450\)\(\upmu\)m, the bandwidth is \(9\) GHz when the reflection coefficient of the frequency band is lower than \(-10\) dB. Therefore, through parameter analysis, the optimal length L\({}_{3}\) of the feed-in transmission line can be known, so \(350\)\(\upmu\)m is selected for the length L\({}_{3}\) of the feed-in transmission line to obtain the best bandwidth and minimum reflection coefficient. Through parameter analysis, the graphic unit of the M1 layer AMC is designed. It can be seen from Figure 9 that two types of AMCs are designed in this paper, and it can be known that the type of AMC will affect the reflection coefficient (S11) from the Figure 10. In the first type, it can be known that the bandwidth is only \(6\) GHz under the reflection coefficient standard \(-10\) dB. In the second type, it can be known that, under the reflection coefficient standard \(-10\) dB, a wider bandwidth and a smaller reflection coefficient are obtained. Therefore, the second type in AMC is chosen for the best performance. Figure 8: Reflection coefficient of L\({}_{3}\) variation. \begin{table}
\begin{tabular}{c c} \hline \hline
**Value (\(\upmu\))** & **Bandwidth (GHz)** \\ \hline
200 & 44.5 GHz–80.5 GHz \\
350 & 30 GHz–41 GHz \\
450 & 30 GHz–39 GHz \\ \hline \hline \end{tabular}
\end{table} 
Table 3: The bandwidth of L\({}_{3}\) variation. The AMC with different periodic array sizes is analyzed, as shown in Figure 12. For example, it can be seen from Figure 13 that, in the AMC with a regular array size of \(7\times 9\), it can be known that the minimum reflection coefficient (S11) is \(-18\) dB.