HSPA+ is an obvious evolution path for many UMTS operators, enabling them to offer users the higher data rates that so many of them crave. Initial HSPA+ deployments can double the data capacity of HSPA and more than double the voice capacity of WCDMA, resulting in lower costs for operators delivering mobile broadband data and voice.

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The visibility of HSPA+ in the U.S. has been raised recently by claims from T-Mobile that its network will let subscribers communicate at 4G speeds in up to 100 markets by the end of 2010. So does HSPA+ deliver 4G speeds? Not if you subscribe to the International Telecommunication Union’s (ITU’s) definition of 4G.

However, HSPA+ can be highly effective in helping UMTS operators extend the lifespan of 3G, keeping it competitive and helping to control costs while servicing their ever more data-hungry subscribers. So, how fast is HSPA+? What can users really expect of it? And, what role does device performance play?

The Role Of Release 7

HSPA+ first came about with 3GPP’s Release 7 specifications, which introduced the use of a higher-order 64-state quadrature amplitude modification (64QAM) modulation scheme as well as multiple-input multiple-output (MIMO) systems. Release 7 also brought enhanced receiver architectures and interference-aware receivers. The highest theoretical downlink data rate supported in Release 7 is 28 Mbits/s. Beneath these headline data rate improvements, HSPA+ also offers more subtle improvements in latency and call setup times.

Nigel Wright, vice president of marketing, wireless, joined Spirent in 1998. Previously, he was sales director at Telecom Analysis Systems, since purchased by Spirent Communications. He received his bachelor’s degree in electronic engineering from the University of Brighton, England.

Since the pioneering work of Telstra in Australia, adding Release 7 HSPA+ support for 64QAM has become a popular migration path for UMTS operators. That’s because it’s a software upgrade in most cases, avoiding the costs and complexities of MIMO implementations that impact both infrastructure and devices.

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