Free Duplex in 6G Mobile Communication: Concept and Advantages

This page describes the Free Duplex concept used in 6G Mobile Communication and mentions the benefits or advantages of Free Duplex with respect to the 6G Mobile System.

Introduction

We’ve witnessed the evolution of mobile communication systems from 1G to 4G, 5G NR (New Radio), and the planned 6G. These cellular technologies are developed to provide different speeds and a plethora of features to mobile users.

A cellular system mainly consists of two parts: the Base Station and the mobile phone users or subscribers. Mobile users communicate with the Base Station with the help of multiple access techniques and/or duplexing mechanisms.

Access techniques include FDMA, TDMA, and CDMA. These access/duplexing techniques allow efficient utilization of network resources (time, frequency, and space).

What is Free Duplex in 6G Wireless Technology?

The figure depicts the evolution of duplex techniques used in mobile wireless communication systems from 1st generation (1G) till the sixth generation (6G).

• Fixed Duplex: In this type, frequency and time resources are allocated statically. Based on this, there are two types: TDD (Time Division Duplex) and FDD (Frequency Division Duplex).

  • In TDD, the same frequency is shared between the uplink and downlink directions at different time instants. Hence, in TDD, the entire bandwidth is used.
  • In FDD, different frequencies are allocated to the uplink and downlink directions, which are used at the same time instants.

• Flexible Duplex: In this type, transmission resources such as time and frequency are allocated dynamically. In very dense network scenarios, large traffic variations have been observed. In such situations, the flexible duplex technique is employed. This duplex technique maximizes spectrum utilization and offers the ultimate user experience.

• Free Duplex: There is no TDD or FDD differentiation in this type. It is a flexible and self-adaptive scheduling mode of flexible duplex or full duplex. Free duplex offers more efficient utilization of spectrum resources by sharing all degrees of freedom in three domains: time, frequency, and space.

Benefits or Advantages of Free Duplex

Following are the benefits or advantages of free duplex:

• It increases throughput.
• It reduces transmission delay.
• It improves spectrum efficiency.
• There is no FDD or TDD resource utilization constraint.
• It offers more freedom and flexibility for Downlink (DL)/Uplink (UL) resources.