As part of our Network Trends 2014 series, Paul Gowans discusses how the continued implementation of LTE-Advanced could help mobile operators over the next year.
Will LTE-Advanced Help Harness the Mobile Data Explosion?
By Paul Gowans, JDSU Mobility Marketing
The LTE-Advanced standard is the ambitious attempt by 3rd Generation Partnership Project (3GPP) to better cope with the mobile data explosion. There are roughly 126 million LTE connections today with users consuming 46 MB of mobile data daily – that’s 168 percent more data than those still on 3G networks. LTE-Advanced will substantially increase peak data rates up to 1G, spectral efficiency up to 30 bps/Hz and the number of simultaneously active subscribers
The technology’s first partial implementation by a major network was in late 2012, it has yet to establish a major foothold outside of South Korea, and very few cell phones currently support it. However, it will gain significant momentum in 2014, particularly in North America. Its feature set is, quite simply, a prerequisite to coping with the new mobile world.
Carrier aggregation is perhaps the most powerful feature of LTE-Advanced. The only practical way to significantly increase data throughput rates beyond spectral efficiency is to increase bandwidth, a.k.a, create bigger pipes. Currently, individual channel bandwidth is limited to 20 MHz, but LTE-Advanced increases bandwidth by combining up to five component carriers, contiguous or non-contiguous, of any bandwidth, yielding a potential total of 100 MHz bandwidth. Given the universal condition of spectrum fragmentation in major operators’ holdings, LTE-Advanced carrier aggregation is a major step forward in making efficient use of existing bandwidth. This isn’t a new concept, as the early days of Integrated Services Digital Network (ISDN) did this on wireline networks; however, aggregation like this applied to a mobile network is a relatively new field for service providers.
So in a nutshell, LTE-Advanced promises to be a lot faster. But as they say, with great speed comes great responsibility. Since LTE-A provides extended capabilities for carriers in terms of aggregation, what results is a potentially more complex network. Moreover, there are further opportunities for something to go wrong between the handset and the network. If a network operator needs to deploy small cells to provide capacity boosts, they’ll need to ensure each device is LTE-A-capable. In some cases, they may be upgradable, in others they might not.
From a user-plane standpoint, the aggregation is just a single bearer. It impacts the radio resource control (RRC), the medium access control (MAC), and physical (PHY) layers of a network’s architecture, and does not affect the core network, the packet data convergence protocol (PDCP) layer, or the radio link control (RLC) layer.
Another important feature of LTE-Advanced is when it is deployed with enhanced multiple input multiple output (MIMO) capabilities. In other words, using more antennas and more receivers per user session. With LTE-Advanced, up to eight different data streams can be transmitted and received by up to eight antennas and eight receivers. This means far-better edge performance, particularly in areas of high interference.
Paradoxically, when an operator does finally implement LTE-Advanced, it may not appear to be a breakthrough event. In actuality, the operator will be merely staying afloat in the ongoing data tsunami.
The key thing carriers need to keep in mind is that adding this extra layer of complexity can create network-visibility blind spots. In order to effectively roll out a new network, accurate measurement and analysis of service delivery are an absolute must. LTE-Advanced should give operators more flexibility in terms of revenue-generating services, but unless carriers can see if they're being delivered properly, they can't improve revenue and earnings.