BDMA: Beam Division Multiple Access in 5G

This page describes BDMA basics, including what BDMA is in 5G technology and BDMA concepts.

BDMA stands for Beam Division Multiple Access, which utilizes separate beams to target subscribers in different regions.

Introduction

As we know, various multiple access techniques have been developed for multiple users to exploit efficient usage of common resources such as time, frequency, and codes. This has pioneered the development of FDMA, TDMA, CDMA, and OFDM techniques.

The main aim here is to provide quality service to subscribers/users at an affordable cost. The most common critical resources, such as time and frequency, have been shared among multiple users using TDMA and FDMA, respectively.

The Korean R & D has devised a new access technique known as BDMA for the fifth generation of mobile wireless communication systems. The full form of BDMA is Beam Division Multiple Access. This technique does not utilize time and frequency resource sharing.

BDMA Basics in 5G

Image alt: BDMA Beam Division Multiple Access

The figure depicts the BDMA technique. As shown here, the base station allocates separate antenna beams to each of the mobile devices. This is done after evaluating their positions and moving speed with respect to the base station. Often, this is communicated by the mobile devices (i.e., stations).

This BDMA technique helps in achieving higher system capacity. Based on position and moving speed, the base station will calculate both the width and direction of the beam for all the mobile stations. All the mobile stations communicate with the base station when they are in LOS (Line of Sight) with it.

In BDMA, all the beams are distinct for individual stations. Hence, simultaneous data transmissions are possible to different mobile stations at different angles. The mobile stations at the same angle can also be addressed by the same single base station based on width, direction, and number of beams. To support more users, the beam is divided three-dimensionally.