xG Technology xMax Works as Advertised

xG Technology (News - Alert) proclaimed in 2005 that they had a revolutionary technology that allows wireless broadband using unlicensed and licensed frequencies. They said they could build the equivalent to a WiMAX (News - Alert) network without the need to spend a massive amount on spectrum auctions and, moreover, that their technology had better range than WiMAX.

It seemed too good to be true and after some years of waiting, the communications industry got impatient. After all, this revolutionary technology had the potential to change the way wireless networks are deployed. If it was real, where was it?

So I asked the company to show us the technology so we could set the record straight. xG responded with an invitation for a visit a short while later.

I drove to xG Technology's Florida headquarters where I met the management team and drilled them with questions. Here’s what I found out.

The company bit off more than it could chew in 1995 and should have waited before talking. It is obvious they underestimated the complexity of what they were trying to accomplish.

xG had to develop a wireless technology in a noisy spectrum from scratch. This is far more difficult than developing technology in a licensed spectrum where interference is a relative afterthought. They had to build base stations, chips, test gear and even a phone. In the world of WiMAX, meanwhile, you can purchase chips from one vendor, test systems from another and phones from other companies. Time to market in WiMAX is much shorter as an entire ecosystem is developing products that interoperate and interconnect with one another. Imagine building it all yourself in spectrum that most engineers will tell you is not usable.

When you realize the size, scope and you might even add lunacy of the undertaking, it makes sense that the company spent $100 million developing it all. Moreover, while they have about 50 engineers today, they averaged about 30 during their corporate history. It does seem impossible when you think about it.

As for specifics about the solution, it currently runs on 902-928 MHz, but it is software definable, meaning it could potentially be used in white space as well. They estimate that 700 MHz spectrum costs about 12 times more than equivalent xMax coverage when you factor in the cost of the frequency auctions.

I was told that one of the company's customers, Townes Tele-Communications Inc., has a few towers and their 100 foot tower has a range of 2.5 miles while one at 350 feet has a six- to eight-mile range and is superior in coverage area to the nearby GSM equipment.

Voice is transmitted over the network via SIP with header compression and other techniques that minimize latency, bandwidth use, etc.

I had a chance to see the digital and RF boards that end-user devices would incorporate. At this point they are two to eight times as large as a comparable WiMAX chipset. but I would expect them to come down in size over time and as they are produced in volume.

The company's first handset, the TX60, has integrated Wi-Fi.

President and CTO Joe Bobier handed me a TX60 phone and told me they are still working on their battery management technology. This phone had none I was told.

With that we made a call and I started talking to the command center from a few feet away. The voice was good – as good as any cell phone for sure.

We then went into the test vehicle, which had a massive power inverter for laptops that ran diagnostics on the phone. The quality was still great.

We drove for 30 to 45 minutes and the voice quality never diminished except in one spot where everyone warned me voice quality would be a bit choppy.

Generally there was no latency or anything unusual. I kept asking the people on the other end to count to 10 when we were near overhead wires or in areas in which I suspected there would be poor reception. Other than the spot mentioned above, the quality never diminished.

As the test ran on, the phone got “fry an egg on me” hot and at some point the sound stopped working. The phone was still connected according to the laptop, but I couldn't converse. We called once more, and after a while the voice couldn't be heard again.

It is worth pointing out that the phone was plugged into the laptop, which graphed its diagnostics and indicated the phone was charging and subsequently running hotter than it would have on batteries alone. It was as hot as early Wi-Fi phones I had tested some years back. Joe suspected the heat was the issue with the phone. I have no reason to doubt this assertion.

In summary, it works. Was it a perfect demo? No. But they never are, and when I compare this to what the wireless carriers have had years to perfect, I came away very impressed.

There are lots of discussions we can have about noise floors in the 900 MHz spectrum and how the company deals with interference, but they are beyond the scope of this article. Moreover, we drove around enough residential and commercial areas that I am satisfied that I experienced a real-world test.

So, who is the target for this technology? Incumbents (playing in other areas), CLECs, cable companies, mobile operators, OEMs, content providers such as Google (News - Alert), MVNOs, etc.

What does it cost? Well for a cool $2 billion you could have 70 percent PoP coverage for 452 metros, or about 90 percent of the population of the U.S. This would include at least a megabit of bandwidth per channel.

I know what you are thinking. Can it scale? The answer, of course, is I don't know. But any customer is going to test it out before they buy, and the company knows this. In addition, the description of how xG lays out its channels leads me to believe they have thought this issue through well.

So was it worth the trip? Yes.

Can xMax from xG Technology change the wireless world? Quite possibly.

But before we go too far down this path it is worth mentioning that areas of coverage are exclusive, meaning only one carrier can pick up each city or metro area. This is an important consideration for companies looking to become next-gen wireless carriers.

For now I believe the question has been answered. At least for my demo, xMax worked well and is real.

When you realize that this company may have found a way to take a frequency riddled with wireless garbage and turn it into a fully functioning wireless voice and data network, you start to see how much of a game changer this could be for the wireless industry. IT

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