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Vanu's AnyWave SDR a 2007 tech winner

The January 2007 issue of IEEE Spectrum magazine features their annual roundup of winners and losers in technology innovation. A long article is devoted to Vanu Bose's software-defined cellular base station and the strategy it embodies. For the full story, see "Winner: Radio Revolutionaries," by Jean Kumagai. Here are highlights:

"Software-defined radio is one of those promising but elusive ideas that's been anticipated for quite some time. The concept is elegantly simple: get rid of the specialized electronics used to process radio signals and instead do everything with software. The result, we've been promised, will be a universal wireless device that can seamlessly handle a range of frequencies, modulation techniques, and encoding schemes. Just as the personal computer replaced the typewriter, the adding machine, and even the telephone, so too will a software radio one day replace your cellphone, Blackberry, and any other wireless device you may happen to use...

"We aren't there yet, but software-defined radio is definitely coming. Don't expect an overnight transformation, though. After all, it took years for the PC to sweep aside the IBM Selectric typewriter. This revolution, too, is bound to happen in a series of incremental but significant steps.

"Steps like this: Vanu, a small Cambridge, [Massachusetts, USA] company, says that this year it will begin selling the first cellular base station that can simultaneously process two waveforms - CDMA (short for code division multiple access) and GSM (global system for mobile communications) - all in software running on off-the-shelf computer servers.

"For cellular carriers, the advantage of such technology is clear.... The market for base stations is huge, totaling some US $45 billion worldwide in 2004, according to ABI Research... It's also hugely competitive, as carriers look for any edge that will allow them to operate more efficiently and at lower cost. Being able to add new services and adapt to new standards by merely tweaking software, instead of replacing or adding hardware, is just such an edge.

" 'In the software radio base-station race, the clear winner is Vanu,' says David Murotake, a telecom engineer whose company, SCA Technica, of Nashua, N.H., focuses on security issues in software-defined radio. Although telecom equipment makers have been incorporating elements of software-defined radio into their base stations for more than a decade, none has taken as radical an approach as Vanu. 'They've already introduced award-winning technology, and in the process they've outdistanced the usual suspects, like Ericsson and Nokia - two of the biggest manufacturers of base stations.

"Or, as a top executive at one of the major cellphone carriers remarked after seeing the new Vanu base station in action, 'This could be game changing.'

"...The typical [SDR] approach is to build in reconfigurable components such as DSPs or FPGAs and then write code for whatever waveform you're dealing with. Processing a different waveform just means writing new software. Once the hardware becomes obsolete, though, much of the software typically can't be reused, because it was written for those specialized components. So you have to develop code from scratch.

"Vanu takes a very different tack. Its engineers start with existing general purpose processors, such as the Intel Pentium or Xeon, and then design software to do all the intense computation required to demodulate and decode the waveform. [Vanu's chief technology officer, John Chapin] likes to say that the company has been riding Moore's Law, taking advantage of the billions of dollars that chip makers spend to make computers run faster...

"The ­signal-­processing capabilities of general-purpose processors continue to improve with each generation, in large part because of all the video and multi­media applications that ordinary computers are expected to handle these days. Good thing, too, because wireless waveforms are only getting more complex. Handling signals from one of the old analog cellphones takes just 20 million instructions per second - a trifling amount for a modern Pentium. By comparison, the CDMA standard requires about a gigaflop, or a billion floating-point instructions per second. And the third-generation phones coming out now demand at least another factor of 5 beyond that, Chapin says...

"Vanu's new Anywave multistandard base station is a software update to a GSM-only version that the company introduced in 2004. While most traditional base-station equipment is bulky, the Anywave is tiny. It consists of standard off-the-shelf servers (the number of servers depends on how many calls the carrier expects to handle), plus the radio-front-end equipment, which Vanu purchases from any of several vendors...

"Vanu's code... is all written in a high-level language, C++, running under the Linux operating system. 'When we change platforms, we maybe rewrite 5 ­percent of the code, versus 50 or 60 percent for our competitors,' Chapin says. In real terms, using general-purpose processors can mean sacrificing some performance for portability. But the difference may not matter. Chapin mentions Clayton Christensen's classic example of how the hydraulic shovel eclipsed the steam shovel back in the 1950s. 'The steam shovel was clearly more capable, but the hydraulic shovel was cheaper, and it eventually became good enough,' Chapin says. 'That’s what we’re seeing here.'

"Nobody else has ever built a commercial device that uses a general-purpose processor to handle two waveforms simultaneously. But Vanu engineers have now done it twice. Five years ago, they developed a dual-standard prototype radio for the National Institute of Justice, the research arm of the US Department of Justice. That device combined the functions of two radios commonly used by law enforcement: a Motorola two-way FM radio and a Datron unit that used a newer digital standard known as Project 25... After trying various approaches [for the NIJ prototype] that all proved too labor intensive, the engineers eventually hit on the idea of using Internet Protocol and sending the packets of data over gigabit Ethernet, which is designed to handle different rates of data, such as e-mail and streaming video. It's also built into just about every server and computer these days, so there's no need to construct a dedicated hardware link between the radio front end and the baseband processor...

"Vanu the company grew out of work that its founder, Vanu Bose, did as a graduate student at MIT, just down the street from the company's current headquarters. Bose formed the company in 1998 to commercialize his ideas, but without a clear idea of what type of product or which market to go after. He looked at public safety and automotive applications and landed some military contracts but found no takers in the commercial sector...

" 'Everyone told us to stay away from commercial [telecommunications] infra­structure,' Bose says. Plenty of start-ups had foundered trying to roll out new products for the telecom sector. But Bose ultimately decided to give it a try...

"The epicenter of the next phase in the software-defined radio revolution is likely to be De Leon, Texas, a town of about 2400 people that is roughly 220 kilometers southwest of Dallas. De Leon's main attraction for the last 92 years has been its annual Peach and Melon Festival. The town also is the home of a rural mobile-phone provider called Mid‑Tex Cellular, which three years ago became Vanu's first commercial customer.

" 'We were looking for new ­technology, something that was more flexible and maybe would allow us to avoid constant hardware changes,' says Toney Prather, Mid-Tex's CEO. The company's existing network was based on older, TDMA (time-division multiple access) technology, and to move to a newer standard, such as GSM or CDMA, the provider faced hefty upgrade costs. Standard base stations run about $50,000 apiece...

"In early 2003, Prather agreed to let Vanu supply Mid-Tex with GSM software-defined base stations on a trial basis. At the time, Vanu didn't actually have a working GSM base station, but its engineers got busy, and within seven months they had software that was good enough for a field trial [see 'Mobile Phone System Passes Texas Test,' IEEE Spectrum, February 2004].

"Since then, Mid-Tex has deployed 29 Vanu base stations, which all run on Hewlett-Packard ProLiant servers and handle about 6 million minutes of calls each month...

"In all, Prather figures he has spent about $2 million on his Anywave network. That's about what he would've paid for traditional GSM equipment, but now he won't need to buy an entirely new network when he adds CDMA. Nor will he need to lease additional T1 lines to get the signals from the cell site to the switch - which can run several hundred dollars a month per line. That’s because the base station architecture is IP-based, so the same T1 can handle any type of call from any carrier...

"What's more, the company can now perform diagnostics remotely over the Web, cutting maintenance costs...

"At press time, Mid-Tex was field-testing the new dual GSM-CDMA software at two of its sites, and Prather was eager for Vanu to give him the go-ahead to upload the CDMA code throughout his network. 'I hope it's any day,' he told Spectrum. 'We're ready now.'

"Anywave deployments so far have been limited to rural areas such as De Leon and certain military installations. But Bose expects to land some much bigger fish within the next year or two. Vanu executives have recently been getting a warm reception when they've demonstrated the new multistandard technology for some of the major carriers...

"Bose says his company's technology could just spark a restructuring of the wireless infrastructure industry. At present, it's still mostly vertically integrated, with companies like Ericsson, Huawei, and Nokia producing nearly all the components, from the base stations to the antennas. Rather than having a single company do everything, Bose suggests, the 'horizontalization' of the industry would result in more agile companies - including Vanu - doing whatever they're best at.

"It sounds like a big leap, but that's precisely what happened in the computer industry 20 years ago, when Digital Equipment Corp., IBM, and other giants gave way to upstarts like Apple, Intel, and Microsoft."

To Probe Further

"Vanu's Web site, http://www.vanu.com, has details about the company's technology, including a white paper on its Anywave base station and copies of technical papers that Vanu staff members have written over the years.

"The SDR Forum, http://www.sdrforum.org, supports the development of software-defined radio technology through its annual meeting and the work of its committees.

"The IEEE P1900 Group, established in 2005 by the IEEE Communications Society and the IEEE Electromagnetic Compatibility Society, is creating standards related to new technologies and techniques being developed for next-generation radio and advanced spectrum management, including software-defined radio. See the committee's Web site at http://www.ieeep1900.org.

"The IEEE DySPAN symposium, http://www.ieee-dyspan.com, to be held 17-20 April in Dublin, [Ireland] will explore topics related to the dynamic use of the RF spectrum.

"In 'Hardware for Your Software Radio,' in the October 2006 issue of IEEE Spectrum, senior associate editor Stephen Cass reviewed a do-it-yourselfer's kit for designing and testing software-defined radio systems (http://spectrum.ieee.org/oct06/4654)." [This is Matt Ettus's Universal Software Radio Peripheral, for the open source GNU Radio project.]

[SDR - 31 January 2007]