Form Follows Function

Sat in a traffic jam lately? It could be because you're traveling on a highway system designed decades ago, when most people commuted from their homes in the suburbs to their jobs in the cities. Today, more people live in one suburb and work in another, but highways haven't changed to accommodate those new patterns.

Wireless traffic is undergoing a similar change. When rates were 70 cents a minute and handsets topped 1,000 dollars, most subscribers were businesspeople, many with car phones. As a result, usage followed more predictable patterns, with traffic concentrated around business districts and highways.

"Now, that's the exception and not the rule," said Bill Brickel, Cellular One-Kansas and Missouri director of technical services. "We're really seeing people who are wanting service to work in areas that we haven't had to address before."

Today, "free" off-peak minutes, 1-rate plans and even prepaid make the cost of wireless more predictable, which in turn makes subscribers more comfortable with using their phones for more than business and emergencies.

"I believe that people are feeling freer using their phones in different places," said Debra Carroll, Bell Atlantic Mobile (BAM) vice president of marketing. "If you can roam up and down the East Coast for the same rate that you can in what would have been your home area, you're going to feel more comfortable making that call when you're away on business or visiting family in another state."

MOBILITY UNPREDICTABILITYBut more pricing predictability for subscribers means less usage predictability for carriers. Today, putting the right capacity and coverage in the right places is starting to mean putting it everywhere.

"On a weekday, it will be concentrated in certain areas of the network where people are commuting to work and working," said Limond Grindstaff, PrimeCo CTO. "On the weekends, you'll still see the same amount of (traffic). We'll see the usage either stay as high on a weekend as on a weekday or possibly even spike up a little higher, but we see that traffic spread out over the network in areas that we normally don't see a high usage volume during the weekday."

One way to ensure that supply will meet demand is teamwork and constant communication between departments. That helps prevent surprises such as a new rate plan that floods the network with more traffic than it can handle.

But maintaining a close relationship can be tough in a large network. As a result, BAM divided its network into semi-autonomous markets, each headed by a local team of engineers and marketers who are free to respond to their areas' traffic patterns and competition. Each team reports to BAM's COO, who ensures that changes in one market won't cause problems in another.

"It allows them to keep close contact with what's happening competitively in that region," said Tony Melone, BAM vice president of network planning and administration. "That works well (for) staying on top of the pricing plans that we're rolling out and what the anticipated impacts of those are going to be."

Even with local marketing and engineering working together, predicting what effect a new rate plan might have on usage patterns is at best an educated guess.

"What I get is a forecast from marketing (of) what they think the demand and usage are going to be," said PrimeCo's Grindstaff. "I automatically assume that that forecast is incorrect because what they're doing is predicting the future, and nobody has predicted the future very well so far. On a weekly basis, we look at what the forecast is, and then we keep trending the actual usage. We also put a build-ahead margin into our networks. On the base-station capacity, we put three months of build-ahead margin so that if the usage trend spikes up, we still have enough capacity and enough time to react."

Forecast accuracy can be improved as actual statistics start coming in.

"The forecast is a living document," said Cellular One's Brickel. "You need to update it constantly. It's a good planning tool, and it requires a very close relationship between marketing, business-development and network people."

NEW USERS & NEW DESIGNSIf there is one reliable guide for forecasting usage, it's that cheaper rates attract more demographics, and both directly affect traffic patterns. After offering bundles that included free off-peak minutes, BAM watched traffic shift by both time of day and location.

"It moved away from the core areas in the city," Melone said. "It moved away from the highway corridors and commute routes (and shifted to) suburbia, where people are using these bundled minutes in lieu of their landline phones. We've had to augment capacity significantly in those areas over the past year."

Falling rates also are a driver of the wireless-as-second-line trend, itself a driver of increased traffic in the evenings. For now, that means adding coverage and capacity in residential areas. In the near future, it could force a fundamental shift in design and pricing.

"The more that occurs, (the more) our network design will have to shift with that," Melone said. "Right now, we're designed for a mobile environment. (With) more second-line and fixed usage, we may have to deploy almost a minicell approach in a residential community."

A shift in network design from providing service mainly to mobile subscribers to serving both mobile and stationary subscribers could affect pricing, which in turn could affect usage patterns.

"The key for the industry is going to be, how do we price that?" Melone said. "Do we have it priced a certain way when they're in that local area? When they take that phone on the road and leave that minicell, do they pay a premium for the mobility? I see that maybe a year away before those types of changes enter into the marketplace. For now, it's going to be our existing network and architecture that will need to support those."

Cellular One's Brickel also sees network design evolving to accommodate changing usage patterns.

"I think that microcells are going to be a bigger part of our business than the towers have ever been," Brickel said. With them, "we can design for those areas where people are going to use their wireless phones instead of their wireline phones."

Even as wireless becomes mainstream, there still can be spikes at different locations or times of the day. Case in point: Pascagoula, MS, home to a shipyard with more than 10,000 employees.

"When their shift changes, we experience astronomical call volume," said Jana Ray, Cellular South advertising and marketing manager. "We optimized our (system) so that we could accommodate those shift changes just by knowing the number of employees, the time that their shift changes, their drive patterns and their usage patterns. We were able to modify our system based on the need of that one market."

Ultimately, the ability to meet those needs also can be a market differentiator.

"That wasn't a rate plan," Ray said. "It didn't increase our revenue. But it probably helped with our customer retention because of the better service in that area."

Cellular One also is looking at ways to accommodate areas with high concentrations of wireless users.

"We're working with our biggest customers to look at local (and) on-campus solutions," said Bill Brickel, Cellular One-Kansas and Missouri director of technical services. "We're also looking at the potential of using smart antennas for capacity management during those peak times."