‘3xMulti’ – a new way of thinking for RAN evolution

The mobile networks today and going forward will be about 3xMulti: Multi-standard, Multi-band and Multi-layer. Ericsson provides a new way of thinking for RAN Evolution to help operators understand how best to manage the challenges of the 3xMulti world.

Operators are facing ever-higher capacity and coverage demands, driven by increased usage of smartphones among consumers and business users, the mobilization of enterprise applications, and developments in the area of Internet of Things (IoT).

As operators roll out 4G LTE networks, and begin to develop their strategies for introducing 5G technology, they are also considering how to make best use of their allocated radio spectrum in the face of rising subscriber numbers and mobile broadband traffic volumes. Many are keen to refarm spectrum currently used for 2G and 3G networks to the newer, more efficient mobile broadband technologies as soon as possible.

However, for most operators this will be a highly complex, multi-dimensional challenge, in which a growing and evolving mix of radio standards, bands and layers will need to be efficiently managed over time to deliver the best possible end-user experience.

Operators typically already have multiple radio technology standards in operation (most commonly GSM/EDGE, WCDMA/HSPA and LTE). Even as new standards are introduced, all these standards are likely to continue to coexist for many years to come. There are several key reasons for this. LTE networks do not yet offer global coverage, while the existing handset fleet is dominated by WCDMA/HSPA and, in many markets, GSM because of the low cost of devices. Furthermore, with machine-to-machine (M2M) applications predominantly based on 2G (with commercial contracts typically stretching over many years), the need to deliver 2G services will continue for years, if not decades, from now.

Many operators also already have two or three radio bands in commercial service. As they add more spectrum bands to increase capacity for mobile broadband with LTE, we’re likely to see at least five bands in various combinations in most operator networks in the near future, as shown in Figure 1 (which shows how a mix of radio standards, bands and layers will evolve over time).

Meeting the multi-standard, multi-band, multi-layer challenge

Figure 1. Operators will need to manage a complex mix of radio standards, bands and layers over time.

And finally operators are implementing multi-layer technology, with small cells complementing the macro network to maximize capacity and coverage in high-density and indoor areas.

It is clear that operators need to take a holistic view of all their spectrum resources as they develop their radio networks over the coming years. They will need to find ways of balancing investment across all technology generations to make best use of radio resources to maximize App Coverage, user experience and revenue growth.

This is why Ericsson is proposing a '3xMulti' approach to radio network evolution to help operators understand how best to manage the complex mix of multiple standards, bands, and layers as efficiently as possible, both individually and as a whole ecosystem.

Meeting the multi-standard, multi-band, multi-layer challenge

With multiple radio bands in service in their networks, it will be vital for operators to maximize the spectral efficiency and utilization of these bands. With features like Carrier Aggregation for LTE and Dual Band Multi-Carrier for HSPA, the network is able to deliver higher throughput, capacity, coverage and therefore enhanced user experience from existing frequency allocations.

Carrier Aggregation for LTE can combine FDD and TDD bands as well as licensed and unlicensed frequencies. Dual Band Multi Carrier for HSPA enables low and high bands to be combined to extend coverage reach and improve spectral efficiency.

With multi-standard radios, baseband units, transmission and controllers, operators will be able to spread their capital investments and operating costs across all generations of radio technology and shift traffic handling capacity to the technology that needs it. Hardware- and energy-efficiency will be greatly enhanced.

Maximizing performance in traffic hotspots and indoor areas will require a multi-layered combination of macro and small cells. This will make radio coordination features between the bands, layers and standards vitally important, with a strong need for radio performance, traffic management and load balancing as well as Self-Organizing Network (SON) automation. The higher the level of integration and coordination, the greater the efficiency gains.

As operators strive to deliver excellent mobile broadband performance in the busiest parts of their networks – city centers, business parks, transport hubs, public venues and hub sites – they will need to deploy extreme capacity sites to efficiently serve the growing volumes of 2G, 3G, 4G, and future 5G, mobile traffic. Ericsson Radio System's modular architecture flexibly expands to meet changing demands with multi-standard, multi-band and multi-layer technology. It eliminates most site acquisition issues, delivering three times the capacity density with 50 percent improvement in energy-efficiency. The new portfolio can also reduce total cost of ownership (TCO) by 20 percent.

In summary, operators will need to manage the challenges of the 3xMulti world: a complex mix of radio standards, bands and layers over time, and this will depend on the successful delivery of a radio network evolution with best performance, robust mobility and maximum spectral efficiency. Ericsson’s fully integrated and coordinated Radio Access Network solutions for the best App Coverage, end-user experience and TCO, support operators’ business needs today and lay a great foundation for 5G.