There has been a lot of press lately about next-generation LTE (Long Term Evolution) and the speeds it will bring to wireless broadband. There has also been a lot about networks upgrading to HSPA+ to achieve similar data speeds. One recent report showed in great detail how much money a network operator could save by upgrading to HSPA+ and not moving to LTE at this point in time.

There has been a lot of press lately about next-generation LTE (Long Term Evolution) and the speeds it will bring to wireless broadband. There has also been a lot about networks upgrading to HSPA+ to achieve similar data speeds. One recent report showed in great detail how much money a network operator could save by upgrading to HSPA+ and not moving to LTE at this point in time.

One of the great things about competition is that network operators can make choices based on their own perceptions of the two technologies, their customer base, existing demand for data, and their projections for increased broadband usage over time.  The decision also needs to be based on the amount of spectrum available to be dedicated to HSPA+ or LTE. LTE can operate in bandwidths of 1.4, 3, 5, 10, or 20 MHz while HSPA+ is designed to be deployed in 5 MHz of spectrum.

A core battle raging between the two technologies concerns the often-inflated claims about data speeds and capacities in a given amount of spectrum. HSPA+ specifications state that data rates up to 56 Mbps down and 22 Mbps up are possible using MIMO (dual antenna) systems. LTE claims data rates of 43 Mbps down to devices in 5 MHz of spectrum and 29 Mbps for an uplink. However, all of these data rates are theoretical in nature. To put this in perspective, T-Mobile USA is promoting its HSPA+ data rates as follows: “Typical real-world downlink and uplink speeds experienced by customers with upgraded 3G will be less than the theoretical peak and will vary based on a number of factors, including location, device, and overall traffic on the local wireless network at a given time.”

In some of its advertisements, T-Mobile states that “typical” data rates will exceed 7.5 Mbps down and 2-3 Mbps up to the network. We really don’t have an LTE comparison at this point since the Verizon network is being built using 10X10 MHz of spectrum and AT&T, which will be using 5X5, has not provided any real-world numbers. However, it is expected that LTE data rates in 5 MHz of spectrum (5X5) will be about the same or a little faster with LTE networks.

One sticking point for engineers is determining in what amount of spectrum LTE will have an advantage over HSPA+. Some claim that this advantage will be seen at 5 MHz while others claim that it will only be noticeable on systems with 10 MHz of spectrum dedicated to LTE. Whatever the case, we are looking at data rates considerably higher than those we are seeing on standard 3G systems, but not anywhere near their theoretical peak rates.

Remember also that regardless of which technology is deployed, data rates are shared data rates. If you are the only data user in a cell sector, all of the speed and capacity are available to you. However, if you are in a cell sector with a number of users, the data rate you experience will depend on the types of data being accessed by the other customers. If several are downloading streaming video, you will notice a difference in both the data speed and the capacity available to you. If all of the users in the cell sector are sending and receiving email or only surfing the web, the data speed will remain fairly high. Your data rate will also drop off as you move away from the center of the cell sector where there is better throughput.

When it comes to deploying LTE, the most aggressive networks are Verizon in the United States and NTT DoCoMo in Japan. In Europe, the migration to LTE will be slower with HSPA+ most likely being deployed first, followed by LTE in hot zones, or areas where demand for data is greatest. Verizon has chosen to aggressively build out its entire nationwide footprint, but it is not clear if AT&T will follow Verizon or start out with LTE only where data demand is highest. 

Data rates for WiMAX, as published by Clearwire, are less than for either HSPA+ or LTE, and there are many rumors that Clearwire will move to LTE over time. One Russian WiMAX operator has already decided to move to LTE for future networks, which makes sense with respect to the size of the LTE market in the next few years. With more LTE systems being built, demand for networks and devices will be higher, thus driving down the cost of LTE implementation and devices faster than WiMAX based on volume.

Regardless of which wireless broadband technology your favorite network is building out over the next two years, the result will be higher data rates in both directions. Even so, we will still see inflated data speeds appear in press releases and statements from the infrastructure companies and network operators (with some exceptions), which could cause customers to be disappointed in the data speeds they actually experience over commercial networks. Once we have both HSPA+ and LTE networks in place and a number of devices for them, we will have a much better idea of the actual data speeds that will be obtainable on a regular basis. In both cases, we will have access to more speed and more capacity.

For the foreseeable future, HSPA+ and LTE devices will be capable of falling back to 3G networks where HSPA+ or LTE has not yet been installed. In some cases, these devices will also provide fallback to 2.5+G data speeds in the more rural areas. So while the battle between HSPA+ and LTE continues to rage on within the wireless marketplace, the customers, who don’t care what the faster technology is called, will benefit from faster speeds and more capacity.

Wireless broadband data usage is growing at a dramatic pace. It will continue to grow and demand could impact the performance of these networks from the beginning. If most customers are convinced by the industry that the wireless Internet is exactly like the wired Internet, and that it can be used the same way, data congestion will become a problem sooner rather than later. This is one reason the FCC in the United States and other governmental agencies in other parts of the world are trying to “find” additional spectrum to allocate for wireless broadband services. There are only a few ways to increase capacity. One is to make more spectrum available at existing cell sites, another is to build additional cell sites closer together, and yet another is to employ in-building femtocells and/or Wifi to improve in-building coverage and to move in-building users off the wide-area network while still providing them with access to all of the network features and functions.

No matter the technology, the same methods for increasing capacity apply equally. The FCC is trying to free up more spectrum, network providers are always building out new sites, and many believe that the combination of femtocells and Wifi will go a long way toward helping with capacity issues. I believe capacity across the networks can also be managed by offering different pricing models. I thought we would see different pricing models based on usage (which we have), based on uplink and downlink speeds (as with today’s DSL and cable services), and based on time of day (midnight to 5 a.m. being the least expensive).

However, T-Mobile just began offering aggressive pricing models that reduce the price of data to $40 per month for 5 GB of data, and $25 for 250 MB. This will put additional pressure on the other wireless broadband providers and may even result in more demand for data services. This would impact network operators’ profit margins, especially since the T-Mobile 5 GB per month plan has no overage charges and is essentially reverting to an all-you-can-eat pricing model. This will hinder network operators’ ability to manage the data flow over their networks to ensure that all customers have equal access to data services.

The FCC is trying to find a way to regulate broadband services and to pass rules that make it mandatory for network operators to allow access by all customers on the same basis. My hope is that these new rules will permit each network operator to manage its own wireless broadband usage and to ensure that each and every customer has equal access to higher-speed data services. This means there will have to be some way to limit data hogs that eat up a higher percentage of bandwidth than 95% of the other customers. It will require a delicate balance here to ensure fair and equitable access for all.

Faster data speeds are coming, or are here in some cases. They are not as fast as many in the industry would like us to believe, but they are a lot faster than anything we have been able to have previously. It won’t matter whether your network operator’s choice is HSPA+ or LTE for the next few years, the migration to LTE will take place over the next five years and as these networks are being built, later releases of the standard will add even more speed and capacity to the networks at very little additional cost to the operator.

Wireless broadband services are shared with other customers within the same cell sector, but having faster data speeds and increased capacity will benefit all of us, whichever technology is deployed and whichever network we subscribe to. Another bright spot is that all of today’s 2G and 3G spectrum can be converted to LTE over time if demand warrants it. If the FCC does manage to allocate 500 MHz of additional spectrum for wireless broadband, we should be able to keep up with the demand. As more video is sent and received over the wired Internet and then over the wireless Internet, the additional speed and capacity will help us get on and off the networks faster, freeing up the bandwidth for others.

The battle over moving toward with either HSPA+ or LTE will continue to be waged by network operators; that is what they do. They look for advantages to attract more customers and keep the ones they already have. The cost of providing wireless broadband will continue to come down as these more efficient technologies are deployed, and customers will benefit from the higher speeds. In the meantime, the industry needs to be more realistic in its claims about data speeds and capacity. Customers who know what to expect will be happier than customers who feel they were promised data speeds that cannot be delivered in the real world, no matter what technology is deployed.

Andrew M. Seybold

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