Like many wireless technologies, the motivation behind FLEX was to make more possible in less bandwidth. Such is the mastery of Bob Schwendeman, a career Motorola man who is proclaimed the “father of FLEX.”
The FLEX promise is one of improved speed, capacity and efficiency, and lower per user system cost compared with other paging protocols, as well as compatibility with those protocols.
But for all its wonder, Schwendeman said he did not expect such rapid and widespread adoption of FLEX, at the time it was created or at the time it was introduced to the market four years ago. Today the technology has been embraced by more than 100 carriers in 30 countries and about 60 companies have licensed FLEX to build pagers, chipsets, network infrastructure and test equipment. By last January, 10 million FLEX pagers had been shipped.
Perhaps it’s Schwendeman’s love for engineering that fueled his perseverance through nearly a decade of developing this new and much better paging technology.
When he started in high school, Schwendeman told his peers he would graduate then study at the Illinois Institute of Technology in Chicago.
“I didn’t know exactly what engineers did, but I knew I liked to build electrical things and that I was really good at it, so I said that’s what I ought to be. Everyone thought I was crazy,” laughed Schwendeman.
When he graduated from IIT, his first interview was with Motorola. Thirty-five years later, it appears he likes the job.
Schwendeman’s first assignment was in Motorola’s Communication division in Chicago during the 1960s. He worked a number of years on secret government projects before transferring into the two-way radio business, where he worked on devices like “handy talkies,” recalled Schwendeman.
He moved to the company’s Florida-based paging division in 1970 where he worked in product development of network infrastructure. After a few years, Schwendeman became product manager for paging terminals and high-speed pagers. He worked on Motorola’s early generation alphanumeric pager, the OPTRX, and on other two-way data devices.
In 1983, Schwendeman was promoted to a staff position, which imparted a greater amount of responsibility and a fairly loose rein.
Motorola said, “do what has to be done,” recalled Schwendeman. “`When you see a hole fill it.’ I still consider that my overriding dictate from the company. That’s where FLEX came from. That was a hole that had to be filled.”
Schwendeman’s idea that became today’s FLEX was seeded early in 1986. British Telecommunications plc-then government-owned-had been running a POCSAG-based paging system at 512 bits per second, and capacity had become scarce. Regulatory agency OFTEL would not assign new frequencies so the carrier increased transmission speed to 1,200 bps.
Schwendeman recognized other systems would eventually require more capacity and increased efficiency.
POCSAG at 1,200 bps “was faster, (allowing) more users per transmitter, but they reduced the ruggedness of the protocol that wasn’t that rugged in the first place,” explained Schwendeman. Also, the pagers’ batteries drained more quickly. “Going faster is good, but not in this manner,” he added.
Schwendeman created a list of attributes for a new paging code, which included increased speed, support for long battery life, economic feasibility, bit efficiency, ruggedness and multiple speed functionality for compatibility with other paging systems.
“We knew larger carriers were going to have to keep finding new channels and this would allow them to pass more in the same amount of spectrum. We figured that if we could put out more bits per second, the economics would be better.”
By the end of that year, “a skeleton was developed you could look back today and say was FLEX,” said Schwendeman.
The FLEX team included experts in areas of modulation, systems research and products. Schwendeman and a few partners worked day to day on FLEX’s initial design, while a dozen others researched for specific tasks related to the project.
“A lot of those part-timers contributed significantly. My major role was making sure we never lost sight between the balance of the goals,” said Schwendeman. “The team worked very well. Within the first year we had a basic structure.”
The first version of FLEX was completed by 1991. “The meat was there for what we believed the marketplace needed in the near future,” said Schwendeman, but still a lot of details needed to be worked out.
“Much of the development was weighing alternate approaches. There was much internal controversy-different ideas about how to approach issues of mixing and queuing,” said Schwendeman, and concerns about when the market would be ready for the new code.
To resolve these issues, Motorola “locked the team in a room for a week,” joked Schwendeman.
By 1993, FLEX was ready to roll. Around that time, “we were projecting healthy growth for the industry,” said Schwendeman. “In less than three years, the size of the populations on systems doubled.”
At 6,400 bps, FLEX offers 10 to 12 times the throughput as POCSAG 512.
Motorola decided to focus FLEX deployment first in North America, as “Great Britain and Japan were developing paging technologies fairly independently,” said Schwendeman.
A good sign
In 1994 Japan adopted FLEX as its national standard.
The country is one of the largest paging markets in the world and Nippon Telephone & Telegraph, the largest telecommunications company in the world, had its own paging code.
“While the new common carriers developed POCSAG as well as the NTT code, we expected NTT would continue to develop its own code,” explained Schwendeman. “Motorola thought maybe they’d like FLEX, but we never counted on it. Looking back, the move from Japan was unexpected,” said Schwendeman.
“In Japan, the market decided that instead of users renting pagers and returning them if switching services, carriers would offer customer-owned and maintained pagers. So it was desirable that (the pagers) should work on any system. This lead to the idea of having one code instead of just a strict proprietary code or two competing codes.”
The FLEX Family
“In the early sixties, voice was the Cadillac of pagers, but carriers couldn’t put many on the system,” said Schwendeman. The number of transmitters needed to support users was very expensive and, as such, the systems were small and coverage limited.
“Voice paging kept sliding, but we knew that the end users really liked voice.”
“Our first thoughts on InFLEXion were in 1987.” After designing a spec version of FLEX, the team figured “we could make a very high class code … some sort of highly compressed voice.”
Motorola believed the market would at some time demand two-way messaging, said Schwendeman, but initial focus was on voice paging.
“The catalyst for voice and data was the [Federal Communications Commission’s] release of what came to be known as narrowband PCS frequency,” in the early 1990s, explained Schwendeman. Motorola requested one megahertz of spectrum be set aside for voice paging.
“We were urging for one megahertz because we thought the marketplace was first going to need it as it grew from simplified to more complex messaging.”
During the same time, paging carriers were applying for pioneers preference awards in the 900 MHz bands for narrowband PCS. Most all but one-Paging Network Inc.-indicated aspirations for two-way messaging.
The ReFLEX and InFLEXion voice protocols were both developed during the next few years.
FLEX’s future
FLEX version 1.8 was introduced last July. “It is extremely flexible and allows for multicarrier roaming,” said Schwendeman. Roaming “was on our original list of things to have with FLEX,” he noted.
Making FLEX faster is a long-term issue, said Schwendeman. “The issue is how much are the carriers filling their systems. Other issues include adding security and increasing co
mpression rates. Roaming still needs development- not as far as the code goes-but in the market deciding how it wants to use it.”
“We think one of the advantages of FLEX not belonging to a committee … (is) you keep the code up with industry.”
On two-way and voice, Motorola continues to look at more applications for its messaging units, like the PageWriter, and how to stimulate market demand for applications including information services.
Motorola said to look for smaller form factors, extended battery life and greater inbuilding penetration. “Once we get a reasonable amount of customers per transmitter, carriers get more generous about coverage. The economics work out so carriers can” offer better services, said spokeswoman Sandy Humphrey.
Schwendeman said he is still filling holes today, as Vice President of the Technical Staff and Director of Strategic Systems for the FLEX Technology and Systems Division of Motorola’s Messaging Systems Product Group.
“I have a reputation for being sort of a low-key bulldog. I don’t make a lot of noise but I never let go.”
