While cell phones are a fairly modern invention--if you consider 1973 ‘modern’--the idea of a telephone that could travel with you is as old as the telephone itself. For decades though, the best anyone could offer were bulky two-way radio devices that were essentially walkie-talkies that filled the trunk of your car, but a couple of key engineering developments and a classic American business rivalry would help lay the foundation for the device that revolutionized the way people communicate.
Earliest Mobile Communications Devices
Since the turn of the 20th century, people have envisioned a world where they would be able to keep in constant communication with each other, free of the restriction of wires and cables. With the introduction of radio communications in the early 1900s, and landline telephone services becoming more commonplace at the time, it wasn’t hard to see why people would think that the invention of real mobile phones as we know them today would happen much sooner than it did.
For most of their history, mobile phones were mostly two-way radios that you installed on something that moved. In the 1920s, the German railroad operators began testing wireless telephones in their train cars, starting with military trains on a limited number of lines before spreading to public trains a few years later.
In 1924, Zugtelephonie AG was founded as a supplier of mobile telephone equipment for use in trains, and the following year saw the first public introduction of wireless telephones for first-class passengers on major rail lines between Berlin and Hamburg.
The Second World War saw major advances in radio technology, with handheld radios coming into widespread use. These advances placed mobile radio systems in military vehicles around the same time, but technological limitations limited the quality of the systems significantly.
This didn't stop companies from offering mobile telephone systems for automobiles to the public in the 1940s and 1950s in America and elsewhere, but like their military counterparts, they came with serious drawbacks. They were large systems that required a lot of power, had limited coverage, and the networks weren't able to support more than a few active connections at a time. These limitations would hamper mobile phone technology for decades and put a ceiling on how fast the technology could be adopted by the public.
Major Developments Towards Modern Mobile Phone Systems
In response to this growing demand for better mobile telephony, AT&T’s Bell Labs went to work developing a system for placing and receiving telephone calls inside automobiles that allowed for a greater number of calls to be placed in a given area at the same time.
They introduced their mobile service in 1946, which AT&T commercialized in 1949 as the Mobile Telephone Service. The service was slow to take off, however, with only a few thousand customers in about 100 localities in total. The system required an operator at a switchboard to set up a connection and the users had to push a button to talk and let go of it to listen, making it more like a military radio than the existing telephone system that people were used to, only wireless.
The service was also expensive, and the number of channels available for active connections remained limited, to as little as three channels in some places, and with a conversation taking up the entire channel for the duration of the call, there could never be more active conversations than there were available channels.
Bell Labs engineers were working on a new system that could improve the efficiency of these channels since the 1940s, however, with Douglas Ring and W. Rae Young proposing the idea of a network of ‘cells’ to help manage the reuse of channels and reduce interference as early as 1947 [PDF]. The technology just wasn’t there at the time, however, and it would be another couple of decades before a pair of Bell Labs engineers, Richard Frenkiel and Philip Porter, would build this concept of cells into a more detailed plan for a mobile telephone network for automobiles. By this time, AT&T had already pushed the Federal Communications Commission to make more of the frequency spectrum available for radio telephones to use, providing more channels for them to use.
Other significant developments in the 1970s enabled automatic cell switching and signaling systems that allowed for devices to maintain a connection as they moved from one cell to another, expanding the area that mobile telephone networks could service. But all of these developments were put to use developing mobile phones in automobiles. It would take an upstart to give us the first cell phone as we know it today.
Motorola's Martin Cooper Invents The First Cell Phone
While Bell Labs was working to develop the system that would become the cellular networks we are all familiar with, what they weren’t having as much success in was in building an actual portable, handheld telephone. They had spent much of their efforts developing what we used to call the car phone--though not anymore since those aren’t really a thing.
The reason the car phone didn’t take off was because of the work of a small company called Motorola and a man named Marty Cooper.
“We believed people didn't want to talk to cars and that people wanted to talk to other people,” Cooper told the BBC in a 2003 interview, “and the only way we at Motorola, this little company, could prove this to the world was to actually show we could build a cellular telephone, a personal telephone.”
Build it they did. With encouragement from his boss, Motorola’s chief of portable communication products John Mitchell, Cooper and engineers at Motorola produced the working prototype for the first cell phone. On April 3, 1973, before stepping into a news conference in Manhattan to demonstrate the new device that would go on to revolutionize communications, Cooper placed the first cell phone call in history.
“I called my counterpart at Bell Labs, Joel Engel,” Cooper said, “and told him: ‘Joel, I'm calling you from a “real” cellular telephone. A portable handheld telephone.’”
Beating AT&T to the punch was a thrilling experience for the upstart Motorola, then taking on a company that exercised monopoly power over American telephone systems.
“When you are a competitive entity like we were,” Cooper said, “it's one of the great satisfactions in life.
The Invention of the Cell Phone Was a Multi-Generational Effort
While demonstrated in 1973, it would be another decade of development before Motorola’s cell phone—the world’s first—made it to market, and commercial cellular service for handheld cell phones began. Selling for about $3,500 at the time, no one—not even Cooper—could see Motorola’s DynaTAC 8000x being the first step on the road to the kind of communications revolution to come.
“I have to confess that [the widespread global use of cell phones] would have been a stretch at the time and in 1983 those first phones cost $3,500, which is the equivalent of $7,000 today,” Cooper said in 2003. “But we did envision that someday the phone would be so small that you could hang it on your ear or even have it embedded under your skin.”
As for whether Cooper accepted the title given to him by history, the father of the cell phone, he felt that the honor should be shared. “Even though I conceived of it,” he said, “it really took teamwork and literally hundreds of people ended up creating the vision of what cellular is today, which by the way is not complete. We are still working on it and still trying to make it better.”