# Oceania's 5G Multi-Tier Fixed Wireless Access Link's Long-Term Resilience and Feasibility Analysis
## 3 5G Base Coverage Network Layout
### 5G Hybrid Beamforming for Massive MIMO  
Combining characteristics of analog and digital beamforming in RF communication channels is known as hybrid beamforming. Further, 5G mmWave networks frequently use hybrid beamforming techniques. By adding phase shifters to each element of the array, the direction of the beam in RF communications with an array of RF antennas can be controlled. Analog beamforming is the term used to describe the application of these phase changes using analog electronics. These analog phase changers had a certain carrier frequency in mind when they were created. If the carrier frequency deviates from the desired frequency, beam squinting happens. The primary beam lobe shifts in angle as a result of beam squinting. This is a challenge for applications requiring high bandwidth, such as mmWave networks [53]. This problem is solved by digital beamforming. Now, the baseband domain may dynamically calculate the ideal weights (phase shifts). Because of this, each antenna must have its own baseband RF processing channel. As a result, the system now costs more and uses more energy. The potential to significantly enhance channel capacity is another benefit of digital beamforming. Spatial multiplexing can be utilized to send out several signals in various beam directions if the beams are small enough. However, this optimization issue is difficult and intricate. The challenges of digital beamforming can be overcome by hybrid beamforming. This will limit the amount of RF chain components and the optimization challenge by incorporating analog beamforming. The capacity of fully digital beamformers cannot be reached by a hybrid beamforming system due to this restriction; however, it has been demonstrated that the performance difference is rather modest when channel characteristics are considered [54]. To achieve maximum control and flexibility in beamforming, it is important to have independent weighting control for each antenna array element in an active array design. However, this approach requires a dedicated transmit/receive module for each element, which can be challenging to implement in massive MIMO communication systems due to cost, space, and power limitations. In such cases, it may not be feasible to have high-performance power amplifiers for every channel as it may exceed the allocated design budget. The MIMO channel model is generic and can be applied to all scenarios, including indoor, urban, and rural environments. The \(U\times S\) MIMO channel's time-variant impulse response matrix is provided [55]. \[H(t;\tau)=\sum_{n=1}^{N}H_{n}(t;\tau) \tag{7}\]  
here, \(t\) represents time, \(\tau\) represents delay, \(N\) represents number of paths, and \(n\) represents the path index. The matrix composition includes \(F_{tx}\) and \(F_{rx}\) for \(T_{X}\) and \(R_{X}\) antenna responses, respectively, and \(I_{n}\) for the dual-polarized propagation channel response of cluster \(n\). \[H_{n}(t;\tau)=\iint F_{rx}(\varphi)h_{n}(t;\tau,\phi,\varphi)\ F_{tx}^{T}( \varphi)d\phi\ d\varphi \tag{8}\]  
Establishing the relationship between the elements of \(T_{X}\) antenna and \(R_{X}\) antenna, \(s\), \(u\) and for cluster \(n\) as follows:  
\[ \begin{array}{rl}H_{u,s,n}(t;\tau)=&\sum\limits_{m=1}^{M}\begin{bmatrix}F_{ rx,u,V}(\varphi_{n,m})\\ F_{rx,u,H}(\varphi_{n,m})\end{bmatrix}^{T}\begin{bmatrix}\alpha_{n,m,VV}&\alpha _{n,m,VH}\\ \alpha_{n,m,HV}&\alpha_{n,m,HH}\end{bmatrix}\begin{bmatrix}F_{tx,\ s,\ V}( \varphi_{n,m})\\ F_{tx,\ s,\ H}(\varphi_{n,m})\end{bmatrix}\ldots\\ &\times\exp\left(\!\left(\!2\pi\lambda_{0}^{-1}\!\left(\overline{ \varphi}_{n,m}\!\cdot\!\tau_{rx,u}\right)\!\right)\exp\!\left(\!j2\pi\lambda_{0 }^{-1}\!\left(\overline{\varphi}_{n,m}\!\cdot\!\tau_{tx,u}\right)\!\right) \ldots\\ &\times\exp(\!j2\pi v_{n,m}t)\delta(\tau-\tau_{n,m})\end{array} \!\!\!\!\!\!\! \  
\(\alpha_{n,m,VV}\) and \(\alpha_{n,m,HV}\) complex gains of vertical-to-vertical and horizontal-to-vertical polarizations of ray \(n,m\), respectively. The angles of departure.