beamforming basic part-1

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In this article we will learn basics about beam forming and why it is needed.

QUS- What is Beam-Forming and its benefits?

As the name suggest beam forming is the forming of beam of RF energy. Fundamentally the electromagnetic wave radiation pattern from a system is focused like a beam from torch or beam.

It is a traffic signaling system for cellular base stations that identifies the most efficient data delivery route to particular user. It also reduces interference for nearby users in the process.

At the same time it is used to detect and estimate the signal of spatial filtering and interference rejection. It will also improve the overall radio environment of a cell by limiting interference to small fractions of the entire space around a transmitter and likewise limiting the impact of interference on a receiver to infrequent stochastic events and thus sometimes referred as beam shaping.

Beam forming is an attractive solution for boosting mobile network performance as it can provide high spectral efficiency which adds a lot more capacity to existing base station sites.

It also helps in improving the link performance and provides an extended coverage area. Beam forming has been known since years but was not supported by LTE specifications in 3GPP release 15. The benefits of beam forming are obtained in practice with massive MIMO antennas.

QUS- How Beam-Forming can help massive-MIMO?

Beam forming can also help massive MIMO arrays that are base stations arrayed with multiple individual antennas, to make more efficient use of the spectrum around them.

The primary challenge for massive MIMO is to reduce interference while transmitting more data from many more antennas at a time. Hence, beam-forming in massive MIMO base stations do signal-processing algorithms to plot the best transmission route through the air to each user which helps the efficiency and helps to utilize all spectrums deployed into it.

Then they can send individual data packets in multiple directions, bouncing them off buildings and other objects in a precisely coordinated pattern. By arranging the packet movements and arrival time, beam forming allows many users and antennas on a massive MIMO array to exchange much more information at a time.

QUS- How Beam-Forming can improve efficiency of millimeter-wave?

For millimeter waves (FR2), beam forming is primarily used to address a different set of problems. As we know that cellular signals are easily blocked by objects and tend to weaken over long distances. In this case, beam forming can help by focusing a signal in a concentrated beam that points only in the direction of a user, rather than broadcasting in many directions at once. This approach can strengthen the signal’s chances of arriving intact and reduce interference for everyone else.

More the antenna elements => sharper the beam shape => concentrated energy => Less Interfered => Great Performance

Usually beams are formed by analog beam forming technique, but for the data transmissions 5G system dynamically uses digital or analog or the combination of both (analog and digital) called Hybrid beam forming technique.

QUS- Can device be connected with multi-beams in release 15?

As the cell coverage is beams based, a mobile terminal in the 5G cell will sync, attach and report from a single beam only and has no relation with multi beam. As stated by 3GPP in Rel.15 "The mobile terminal will only connect to a single beam, multi-beams connection is not supported".

In Upcoming Part we will learn more about Beam-forming and its interview question and its answer. And for more learning please go through our 5G and LTE page.

Stay tune for more Update…………………

Pinal Dobariya…