Simple Spotwave Z1900 gives cell reception a boost

As more and more enterprise applications expand to cover handheld wireless platforms, smart phones and radio-enabled PDAs are becoming critical pieces of enterprise infrastructure. Powerful as they have become, they are at the mercy of a usable signal from a cell tower. That reliance can lead to the fascinating sight of executives wandering halls and cubicles, raising and lowering their phones while they count the number of bars in the display.

Boosting reception is not as simple as increasing the altitude of the phone’s antenna; metal, concrete, and other construction materials create pockets of good and bad reception throughout a building. It would be so much simpler if the cell tower was in the room, though perhaps not very practical. That’s the concept behind the SpotwaveZ1900 cell phone signal booster. The Z1900 competes with products from Wilson Cellular, Cellphone-Mate, and other companies, though I haven’t had an opportunity to test any of these.

At a very important level, the Spotwave Z1900 is simplicity itself. It comprises two main components: an antenna/receiver NAU (network access unit), and a transmitter CU (coverage unit), connected by a 35-foot cable. The basic idea is this: You put the NAU in the location that gets the best cell reception and the CU in the location where most people want to use their phone.

There isn’t any management to be done, so no fancy administrative consoles or Java applications to host on a remote system. The work of putting the Z1900 in service is all up front, and the vast majority of that work is in the form of the site survey to determine the best location for the NAU.

It would be nice if Spotwave provided a tool of some kind to assist in determining the best place for the NAU. There are, however, plenty of solutions out there to help in that task. It’s tempting to think that simply putting the antenna unit in the highest possible location is the best course of action, but it’s not nearly that simple. You may find better reception at desk level in one corner of the office than near the ceiling in another corner.

I conducted my survey using a fistful of smart phones. I found that the five-bar strength meter ubiquitous to the industry provided enough detail to be useful in deciding on a location for the unit.

As an aside, allow me to urge you to exercise some creativity as you’re conducting the survey. The occasional grand jetéor plié thrown into the mix might not make the survey any more accurate, but they will entertain the dickens out of your co-workers. At least, they seemed to entertain mine.

When you’re conducting an RF survey for this purpose, keep one thing firmly in mind: The Z1900 is not an electronic alchemist, creating cell transmissions out of the pure ether. It only amplifies the signals. Thus, Spotwave recommends that you find a location with at least two bars of signal strength, which seems a good suggestion. I found that the Z1900 boosts reception well if it has even one bar to work with, though it really should be one bar that’s almost two, rather than no bars that might be one on a good day. You get the point.

After you’ve fixed the location of the NAU, you’ll want to place the CU. There are two broad guidelines to follow at this step. First, you’ll want to place the CU as near as possible to the people who will be using smart phones. That’s just common sense. Next, you’ll want to make sure there’s as much physical separation as possible between the units on the opposite ends of the cable. It might not make sense to you unless you’ve studied radio design, but placing them too close together will result in worse performance — perhaps much worse performance.

I experimented with placement in my lab and found that I lost at least one bar of signal strength and as many as two if I placed the units right next to one another. Plan on at least 10 to 20 feet of separation to make sure you’re getting the most out of the Spotwave.

What is the most performance you can wring from the Spotwave? When I had everything properly set up, I went from two bars of signal strength to five. That’s a major improvement which meant using the smart phones changed from an adventure to a productive pursuit. Be aware, though, that the Z1900 isn’t as powerful as a cell tower: Once you get beyond 40 to 50 feet from the CU transmitter, the improvements quickly fade. (The company says that a single unit should cover a 2,500-square-foot building, but in my testing, I found that performance varied dramatically depending on walls, plumbing, and other architectural aspects.)

Spotwave went to great pains to tell me that the Z1900 is intended for T-Mobile or Sprint phones since both of these carriers concentrate their services in the 1900MHz band. The fact is, though, that the Z1900 is carrier-agnostic and boosted the indicated signal on an AT&T Blackjack by the same margin as seen on the T-Mobile and Sprint smart phones used in testing.

The bottom line? If your home or office is in an RF-challenged area and smart phone performance is important, then the Spotwave Z1900 can make things much better. If you get absolutely no signal, be careful: The Z1900 is not magical. But if you’re just looking for those last two to three bars of signal strength, though, the Z1900 could be a great investment. The hard part is figuring out the best locations for the NAU and CU: Once that’s done, the Z1900 just sits there, making life better for all the smart-phone users in the organization.