Editor’s Note: Welcome to our weekly Reader Forum section. In an attempt to broaden our interaction with our readers we have created this forum for those with something meaningful to say to the wireless industry. We want to keep this as open as possible, but maintain some editorial control so as to keep it free of commercials or attacks. Please send along submissions for this section to our editors at: dmeyer@ardenmediaco.com or tford@ardenmediaco.com.
LTE is like a wireless Shangri-La, a shining paradise full of promise. What business, in any industry, wouldn’t want to deliver more and better services and improve customer quality of experience while reducing operating costs? LTE is supposed to do exactly that.
While there’s every reason to think that the technology will deliver on the promise over time, it’s clear that early deployments face major challenges when it comes to delivering on the full promise of LTE.
Challenges abound
For starters, don’t look for fully functional LTE-enabled handsets in 2010. There are a lot of dominoes in the line between Point A (creating a standard) and Point Z (a person talking with an LTE handset while uploading a video to their Facebook page). Chipset and device vendors are early in that line and until their dominoes fall, a generally available LTE handset isn’t on the cards, although testing of data cards and embedded modules for PC connectivity over LTE is going on now.
Commercial LTE handsets will need the addition of voice support. And small handset form factors present additional challenges when it comes to implementing the complex multi-antenna arrangements needed for LTE. Fully integrated, multimode chipsets with low-power consumption will also be required.
Not all operators have adequate available spectrum to support the radio channel bandwidth needed to fully deliver on LTE’s promise. Then there’s the issue of the access and RF networks. LTE introduces an unprecedented level of complexity, including higher-order modulation types, new access schemes, and MIMO (Multiple-Input, Multiple-Output) radio technologies.
That’s challenge enough, but there’s more. Applications for an LTE-only device will be limited. Almost all practical commercial devices will need to support multiple legacy technologies and associated bands. Compounding this requirement, many early LTE deployments will be in new bands such as 700 MHz and 2.6 GHz, so global roaming will need multi-mode, multi-band support that goes well beyond anything implemented today. And users will expect all this to happen seamlessly.
Putting the promise of LTE to the test
Solutions of this complexity require extensive testing, a component of the schedule that requires time. LTE’s flat all-IP based core network, with its simplified architecture
and open interfaces, is a multi-vendor installation. Trials have highlighted complex interoperability issues that require time-consuming troubleshooting and resolution.
Rigorous performance testing of networks and devices is critical to ensuring customer quality of experience and maintaining long-term loyalty. Unlike higher-level services, fixes to the physical infrastructure often can’t be accomplished through software patches or protocol stack upgrades. Hardware design and performance issues must certainly be caught pre-deployment, and most definitely must be addressed pre-launch. If absolutely necessary, a base station can be replaced post-launch (although it is the most expensive and reputation-damaging time to do so) but once thousands of mobile handsets are in the field, everyone is at the mercy of the design and testing.
Then there is what runs over the new network. LTE devices and a multi-technology access network open the door to the broad range of new applications that LTE promises. And those new applications bring with them a requirement for an IP-based backhaul network with significantly increased throughput and decreased latency.
Infonetics Research targets 2010 as the year data traffic will exceed voice traffic on mobile networks. LTE base stations could require up to 300 Mbps of throughput, a significant increase over existing 2G and 3G base stations. There also the major, not-yet-fully-resolved question of how voice service, with the appropriate QoS, will be handled over an LTE network.
In addition, while the nuts and bolts of an LTE launch should be transparent to the customer, the expectation is that LTE must launch with new services, not just a new infrastructure for existing services. Consequently, deploying LTE backhaul is not merely a question of increasing throughput. The complexity of LTE doesn’t stop at the radio link, but extends throughout the entire network.
New services require a mix of transport technologies and protocols across multiple network layers. Backhaul is no longer an issue of simple TDM circuits or satellite links. Building an LTE mobile backhaul network means creating a complex and robust service implementation spanning from the physical layer to the application layer. Validating the performance and reliability of such a network goes far beyond continuity check and circuit verification. It requires sophisticated test methodologies that employ realism in the lab to uncover, locate and resolve inter-layer problems that don’t surface during routine, single-dimensional testing, but that will most certainly surface in the less-controlled post-launch real world where the customer lives.
While it is potentially possible to resolve service problems post-deployment, it’s not advisable. Advance press about the capabilities of LTE has been growing over the last 18 months, highlighting the dissatisfaction of many subscribers with their current service and increasing the expectation of a drastically improved customer experience.
Leading mobile operators realize that the complexities of LTE, together with its immature standards, only intensify the challenge. Early deployments need to focus on not just delivering capable devices, but ensuring that they support the necessary services and don’t suffer from dropped calls, slow download speeds or spotty coverage.
LTE is as much promise as it is technology
Launching with a partially fulfilled promise is a recipe for customer churn, lost loyalty and lost revenue. The main emphasis of mobile operators that are planning LTE service offerings in 2010 and beyond needs to be on:
• High data rates with reliable connections
• New services with improved quality of experience for the customer
• Lower operating expenses and improved profitability
To date, the history of the development of LTE is the story of a well-considered, comprehensive approach to the difficult problem of migrating to the next generation of wireless communications. For example, the principle of self-organizing networks running on a flat IP infrastructure is an intelligent alternative to address the need to simplify deployment and maintenance, ultimately reducing operating cost.
Given this approach, it would be a shame to falter in the home stretch. The launch of LTE should feature seamless multi-generational network support. Validating the performance and interoperability of the devices and networks that implement this increased technological complexity is paramount. It requires test schedules and methodologies that don’t compromise service performance, subscriber quality of experience, or profitability goals.
If the industry plans and executes aggressive, timely plans for comprehensive testing of performance and interoperability, then LTE can deliver on its promise.
Nigel Wright is vice president of marketing for wireless solutions at Spirent. With more three decades of experience in the telecommunications and wireless industries, he has a unique insight into the needs of telecom operators and manufacturers and also a first-hand look into the market trends and issues.