It’s not an easy answer, and we need to analyze a lot of “variables” in your network.
Advanced antenna systems (AAS) or smart antennas (SAs), will be necessary in delivering enhanced mobile broadband (eMBB), ultra-reliable low-latency communications (URLLC), and massive machine-type communications (mMTC), which are considered three pillars of early 5G use cases. Upgraded antenna technologies, such as massive multi-input multi-output (mMIMO), sub-6 GHz and millimeter-wave (mmW) carrier aggregation (CA), and full-dimensional (FD) beamforming/MIMO (FD-MIMO) are also considered essential antenna technologies that enable 5G use cases.
You seems to be using passive antennas: Single antennas (generation 1), Cross polarized 2x2 MIMO and 4x4 MIMO (generation 2).
And maybe also Active Antennas like 64 element FD-MIMO (generation 3) and mMIMO (generation 4). The progression of antenna technology as antennas and radio systems have adopted more digital techniques and RF integration.
For 5G, certainly passive antenna will is needed, generally for above 2.5 GHz.
The 3.5 GHz band is looking to be particularly important, as it’s likely to be globally harmonized.
For millimeter-wave (mmW), Active Antenna will be required, as they will for sub-6 GHz mMIMO.
Here it is important to note: one of the biggest misunderstanding about 5G is mMIMO. Even the definition of mMIMO is misunderstood.
Basically a mMIMO link means more than 64 or more antenna elements on one side of the link and much fewer antennas on the other side of the link, tipically 2.
So, for a mMIMO array of 64 elements, at mmW specifically 28 GHz the dimensions of the array will be 2x2 inches, but for 3.5 GHz, the array will be much larger, tipically 16x16 inches for the 64 element array.
mmW mMIMO is different for Fixed Wireless Access (FWA) versus Mobility.
For the FWA case, obviously the target is stationary: it’s your home.
Think of the beam from the mmW Access Point (AP) as a firehoses of data that jumps quickly from one home to another, filling up the data buffer there, storing data for streaming of video and for browsing of the web. The beam jumps from home to home serving up each home data needs.
So basically you have a Gigabit per second firehose of data jumping from home to home, in miliSeconds.
One of the biggest challenges Operators face with 5G is adapting to the new mMIMO antenna technology.
Among the challenges are: How do you measure the beam pattern of a mMIMO antenna? How do you radio Plan? How do you assess one product performance against other? How do you Drive Test a mMIMO antenna?
From the overall industry and antenna perspective, there are some interesting points to consider.
For sub-6 GHz mMIMO:
Will the spectral efficiency gains outweigh the additional cost of the antenna, the reduction in reliability and the cost of using up additional tower space?
For mmW: Whats is the amount of densification that’s needed, the number of base stations, the issues with the handset blockage ans the dense radiation from the handset antennas.
While passive antennas play a role in 5G networks, active antennas, such as our solutions for Advanced Antenna Systems (AAS), facilitate technologies such as beamforming and beamsteering through mMIMO technology.
5G NR is not only deployed in TDD bands, but also in mmW and <3.GHz Frequency Division Duplex (FDD) bands. For mmW bands today, active antennas commonly use hybrid beamforming for cost and efficiency reasons.