In less than a decade, the smartphone has become the device of choice for mobile users, both in mature markets and developing ones. The network ‘engine’ behind this growth has been WCDMA/HSPA … and it continues to be today. The challenge for operators now is to maintain and enhance the performance, quality and efficiency of their WCDMA/HSPA networks as they build out 4G LTE and future 5G networks. Ericsson’s new Zero Touch WCDMA concept gives operators the tools to do just this.
WCDMA/HSPA is by far the world’s biggest mobile broadband technology, with more than two billion subscribers worldwide … and counting. WCDMA/HSPA subscriptions are still growing at around 25 percent annually, and the technology is expected to cover 90 percent of the world’s population by 2020, when it will serve some 3.8 billion subscribers.
This is because WCDMA is the only technology that provides great voice and app coverage everywhere for the whole device ecosystem – now and into the foreseeable future. It will be the basis of mobile broadband services for the many millions of people with WCDMA-only smartphones and for those who live and work in areas without 4G/5G coverage.
Even in areas with 4G LTE coverage, studies show that smartphone users in some markets still spend around half their time connected to WCDMA/HSPA networks. Furthermore, WCDMA/HSPA will continue to handle between 30 and 40 percent of all voice traffic globally.
This means operator’s need to be innovative to ensure WCDMA offers the best customer experience, at the lowest possible cost, with the maximum spectrum efficiency and manageability. But this requires expert WCDMA knowledge and expertise that is in diminishing supply as operators focus their attention on new technology rollouts.
Ericsson’s new concept Zero Touch WCDMA meets this challenge by addressing the three key pillars of performance, efficiency and innovation, served by three solution components:
- Ericsson WCDMA Flow of Users which is designed to radically enhance network performance by managing the time that subscribers use mobile broadband resources
- Zero Touch which reduces ongoing costs substantially by defining a network operations ‘Gold Standard’ of parameters and settings
- MBB Expander & HSPA Innovations which dramatically reduce and simplify the expansion of WCDMA/HSPA mobile broadband coverage at the many hundreds of thousands of current GSM-only sites.
Today, the typical WCDMA/HSPA downlink data rate is little more than 2 Mbps; best-in-class networks are about 70 percent better than this. Operators need to bring their WCDMA/HSPA networks closer to 4G LTE performance to ensure a consistent user experience.
The Ericsson WCDMA Flow of Users solution (illustrated in Figure 1) takes an innovative approach to increasing WCDMA network performance and enhancing user experience; by ensuring users spend as little time as possible in the ‘active’ state.
This is good for several reasons. A short active time is what all users want; they want to upload and download as quickly as possible. Ensuring users fall back into the semi-active state as much as possible makes more room for users in the active state, so significantly improving consumer experience and increasing overall network capacity. Users are able to enter the active state, with high downlink and uplink data rates, without delay.
Flow of Users network operation is implemented through a carefully selected set of Ericsson WCDMA features and network parameter settings, based on experience of tuning networks in both low- and high-load situations. The features typically increase downlink and uplink at the cell edge, where the cellular network is generally weakest.
Figure 1. Ericsson WCDMA Flow of Users solution
Operator networks where Ericsson has implemented the Flow of Users solution have seen significant improvements in both voice and data user experience. On average, downlink user throughput has been increased by 55 percent and uplink throughput by 42 percent, while data volumes have increased by 49 percent in the downlink and 31 percent in the uplink.
Yearly network upgrades are vital to keep network performance competitive and to enable more stable and efficient operation. However, a typical software release roll-out currently takes around nine months on average to complete. In best-in-class networks the upgrade can be completed in less than three weeks.
The Zero Touch solution component is designed to cut the time operators spend tuning and touching their networks to the bare minimum. It builds on the Flow of Users concept to enable operators to define a Gold Standard for features, parameters and configurations based on Ericsson field experience and recommended settings. By implementing this standard at all sites, operators will be able to provide the excellent consumer performance irrespective of network load.
With such a Gold Standard implemented at every site, RAN software upgrades run faster (typically within weeks, rather than months) and with fewer hitches, as all parts of the network have the same parameter settings and features. New features and updated recommendations are implemented in the Gold Standard and rolled out across the network during upgrades. Following an upgrade, the WCDMA/HSPA network is set in a maintenance mode and only requires capacity dimensioning and deployment of new nodes. During this Zero Touch period (typically of 9–10 months) the operator can implement a network freeze or run (external) performance benchmarking (illustrated in Figure 2).
Figure 2. The Zero Touch WCDMA upgrade cycle
Operators need a way to get from today’s mobile broadband coverage average of around 65 percent population coverage to more than 90 percent over the next few years as cost-efficiently and profitably as possible.
Today, there are hundreds of thousands of legacy GSM sites where current approaches to remodeling or expansion for mobile broadband coverage are too expensive and cumbersome.
Ericsson’s MBB Expander & HSPA Innovations solution changes that by enabling the GSM site and equipment to be reused to the fullest extent and boosting WCDMA/HSPA user experience. The solution combines new hardware features like Intelligent Antenna Sharing, the improved DUW11 digital unit and Psi Coverage with HSPA innovations including Uplink Coordinated Multipoint, Narrowband Interference Rejection, Dynamic Power Sharing and Data Acceleration.
Together, these innovations have been shown to provide a 60 percent reduction in total cost of ownership compared with a conventional new 3G site.
By continuing to build on the three pillars of performance, efficiency and innovation, WCDMA will continue to drive and support the success of mobile broadband around the word for many years to come.