Where 5G is concerned, antennas can no longer be taken for granted. Directionality, latency, increased transmission rate, antenna size, higher frequencies, and shorter wavelengths are on the list of what’s unique regarding 5G antennas. In fact, antenna design relies on the form factors of end devices and the preferences of the OEM. So, what should you know to aid in your antenna selection? Here’s a look at the differences between 4G and 5G antennas, a look at MIMO and beamforming, and the challenges that 5G antennas still face.
Departures from 4G antenna technology includes:
- 5G antennas use shorter wavelengths so they can be smaller
- 5G antennas based require a line of sight to connect
- They can be used near other wireless signals without interference
- They comprehend the type of data requested and can switch into lower and higher power modes based on type.
- They require less power
- They support more than 1000 more devices per meter
- They increase precision while reducing latency
- Higher frequencies for 5G support fast data
- Antennas targeting different applications balance size versus gain tradeoffs
5G specialized antennas optimize an application-specific range of frequencies. For example, below 2 GHz is used for indoor and broader coverage areas electromagnetic waves travel far and through objects. The C-band: 2–6 GHz is a combination of coverage, capacity, and the super data layer. Frequencies larger than 6 GHz provide a high bandwidth but require a direct line of sight.
5G New Radio (NR) is the global standard for a unified, more capable 5G interface and radio access technology. Its goal is significantly faster and more responsive mobile broadband and enabling mobile technology to connect and redefine many new industries. 5G NR uses modulation, waveforms, and access technologies, allowing the system to meet the needs of high data rate services, low latency, and those needing small data rates and long battery lifetimes. In addition, it supports existing services and is forward compatible with future requirements.
Here’s a look at 5G antennas and what some of the advances mean to you.
MIMO Technology
Multiple Input Multiple Output (MIMO) intelligent antennas are the fastest-growing type for 5G. With this antenna, the serial data to be transmitted is divided into multiple data streams, each modulating an individual carrier. The signals are then transmitted simultaneously over the same bandwidth. The use of multiple streams improves reliability and boosts data rates potentially to several gigabits per second.
Key to the 5G NR infrastructure is active antenna arrays allowing multi-user MIMO to provide individual mobile devices with a high transmission rate.
The overall physical size of the 5G massive MIMO antennas is similar to 4G, however, with a higher frequency, the individual antenna element is smaller, allowing more than 100 elements in the same physical case. In 3D MIMO and massive MIMO devices, several transmitter and receiver units are housed in one terminal device.
The Agility of Beamforming
5G smart antennas concentrate RF signals where they are needed most via beamforming– focusing a narrow beam exactly where needed. This capability is based on advanced signal processing algorithms that determine the best path for the radio signal to reach the user, increasing efficiency and reducing interference. It also prevents fading caused by interfering objects when mmWave RF is used. The narrow solid beams travel farther, penetrating buildings and obstacles more effectively. The ability to position beams over a wide-angle minimizes or nulls interfering solid signals. The technology that provides this capability is phased arrays, panels of many small antenna elements, each with its one TX and RX, gain control and phase variation.
Transmitters continuously track receiving equipment, recalculating optimum data paths, making adjustments in real-time. This prevents interrupted data connections when 5G are moving or when signal paths are blocked.
Challenges Remain
5G is complex, and appropriate antenna selection is imperative. Here are some of the challenges that remain with the technology and with available antenna technology:
- Most 5G super-high frequencies work only when there is a direct line-of-sight between the antenna and the device receiving the signal. The frequencies are easily absorbed by humidity, rain, and objects in the way, causing the signal to drop in a matter of just a few feet
- Testing is a top challenge in 5G antenna designs. 5G antennas are active, and they beam their transmissions to specific devices so that a static test won’t show how an antenna will perform when communicating with 1,000 moving devices in a noisy environment
- 5G deployments are increasing; however, they still involve installing low-frequency 5G to work collaboratively with 4G LTE
- A 1GHz signal, which is in FR1, has a wavelength of about 30 centimeters and a 28GHz signal in FR2 has a wavelength of 1.07mm, and one antenna will not work for the two signals. 5G devices operating in both bands require at least two sets of antennas, a critical design challenge for small devices and cell phones
- Tightly clustered antennas for large MIMO architectures create performance challenges for electronic components. At high frequencies, the physical distance between antenna elements may be small
- Cell phones are already packed with antennas, and adding more to support the full range of 5G frequencies is challenging for the limited real estate. They need MIMO antennas for high-performance and antennas located on a phones’ edges and corners to support beamforming
- Designing 5G phased-array antennas for 5G mmWave requires more knowledge on fundamental concepts, array antenna design practices, mmWave signal propagation behavior
- The conflict between requirements for smaller device sizes and larger antenna bandwidth is a top challenge. A solution is using an active antenna system design
- With more antenna elements and higher frequencies, greater power and heat dissipation must be designed in
5G antennas will be found virtually everywhere, and tech advances are happening at 5G speed. Selecting antennas for your design will remain an exciting process for quite some time.
