Within the realm of wireless communication, beamforming or spatial filtering is a signal processing technique and traffic-signaling system that involves focusing and directing a signal-bearing electromagnetic radiation toward a specific target instead of broadcasting the electromagnetic waves in all directions. Through this technique, the transmitter and receiver are communicating essentially in a line-of-sight fashion.
Several processes take place in processing and directing a signal toward a targeted point. These include controlling the transmitted signal amplitude and phase according to the desired application and channel, focusing an electromagnetic wave in a concentrated beam of signal, as well as identifying the most efficient route for data delivery to a particular device or the direction of an end-user using signal-processing algorithms.
Pros: Advantages of Beamforming
The obvious advantage of beamforming is that it results in a more direct communication between a transmitter and a receiver. More specifically, in wireless communication, this translates to better connection and improved overall network performance as determined by a more stable and reliable connectivity and faster data transmission.
Below are the specific advantages or benefits:
Boosts the power of electromagnetic waves by concentrating them in a single beam, thus extending the travel potential of a signal
Reduces frequency interferences from surrounding electromagnetic radiation coming from other sources because signals are directed toward defined and targeted areas
Improves data transmission speeds and efficiency while minimizing errors by ensuring the transmission of higher signal quality while also
Allows multiple connections to a particular base station, router, or source due to targeted communication and reduced frequency noise
Cons: Disadvantages of Beamforming
Despite the aforementioned advantages, beamforming has one notable disadvantage: it requires the utilization of computing resources. The processing requirements of implementing and maintaining this technology have cost, hardware, and energy implications.
Below are the specific disadvantages and limitations:
High cost of implementation that adds to the overall network infrastructure cost and cost of manufacturing of end-user devices or products
This signal processing technique also requires the use of advanced digital signal processing chips that add further to implementation cost
Concerns over energy efficiency because power consumption is considerably higher than omnidirectional broadcasting and communication
End-use devices would need larger battery capacities due to the power-hungry and processing-intensive requirement of beamforming
There are several scenarios in which the time and power consumption requirements of beamforming outweigh its advantages or benefits
Reduction in network area coverage because signals travel in a line-of-sight fashion that requires a user to be situated along the direction of the beam
The Applications of Beamforming
5G Cellular Network Technology
One of the underlying technologies behind the fifth-generation standard of cellular network technology is beamforming. For starters, it complements Multi-User MIMO and massive MIMO systems. The signal processing technique allows a particular massive MU-MIMO base station to efficiently use the spectrum and reduce interference while transmitting more information from multiple antennas at once.
Beamforming specifically enables access points equipped with MU-MIMO capability to determine the best signal transmission route by sending individual data packets in different directions and choreographic their movements and arrival time. Hence, it allows base stations and multiple end-users to communicate simultaneously and exchange more data at once, thus defining one of the advantages of 5G.
Directing a signal toward a particular target also improves the efficiency of mmWave 5G networks. Because these networks use electromagnetic radiation within the upper limits of radio waves and within the range of microwaves, signals cannot travel at longer distances and are more susceptible to physical obstructions and nearby frequency interferences.
Beamforming focuses a signal in a particular direction to ensure that it remains intact while reducing interferences from other signals or frequencies from the surrounding electromagnetic waves. Note that signals broadcasted in different directions would overlap. Overlapping can produce interferences. However, signals that travel in a line-of-sight fashion have a minimal tendency to interfere with one another because of minimal overlapping.
Improving Wi-Fi Network Performance
The introduction of 802.11n Wi-Fi standard in 2008 also came with support for implementing MIMO technology in wireless local area networking. Beamforming requires MIMO technology to send out multiple overlapping signals. Hence, s few wireless routers based on 802.11n Wi-Fi standard also came with capabilities to process and direct signals to a targeted point.
But the 802.11n standard does not have specifications for implementing a technology for processing and directing signals. Hence, beamforming did not quite take off in Wi-Fi technology. Nevertheless, the introduction of the 802.11ac standard in 2016 came with a set of specifications for defining the implementation of this signal processing technique.
More wireless routers in the market have now included beamforming as an added feature do capitalize on the advantages of this signal processing technique. Although numerous manufacturers and brands have used different branding names and trademarks to market this added feature, such as the AC Smart Beam of D-Link, they are all based on the same technology and standard.
Other Applications of Beamforming
The signal processing can be used at both the transmitting and receiving ends of wireless communication equipment and devices. Hence, apart from network base stations and wireless network routers, the technology also appears in several end-use communication devices such as smartphones, personal computers, and other smart consumer electronic devices.
Beamforming has also been utilized in radar detection systems. Earlier radar technology requires mechanically moving and steering transmitting and receiving parabolic antennas to aim at the desired direction. Signal processing techniques reduce the need for physical movements and dependence on the physical structure of antennas by shaping radio waves and directing them toward a targeted point as a concentrated beam of electromagnetic wave.
Outside the realm of wireless communication technology, the technique has been applied in navigation and ranging technologies using mechanical waves, particularly in sonar systems. Furthermore, it can also be used in extracting sound sources in a particular area or room, thereby enabling the extraction, identification, and filtering of different sound elements.
FURTHER READINGS AND REFERENCES
- Ali, E., Ismail, M., Nordin, R., and Abdulah, N. F. 2017. “Beamforming Techniques for Massive MIMO Systems in 5G: Overview, Classification, and Trends for Future Research.” Frontiers of Information Technology & Electronic Engineering. 18(6): 753-772. DOI: 1631/fitee.1601817
- Konsyse. 2021. “Electromagnetic Radiation: Characteristics and Properties.” Konsyse. Available online
- Nordrum, A., Clark, K., and IEE Spectrum Staff. 2017. “5G Bytes: Beamforming Explained.” IEEE Spectrum. Available online
- Van Veen, B. D., and Buckley, K. M. 1988. “Beamforming: A Versatile Approach to Spatial Filtering.” IEEE ASSP Magazine. 5(2): 4-24. DOI: 1109/53.665