CDMA, or code division multiple access, can actually be traced back to the 1940s. Hollywood actress Hedy Lamarr and composer George Antheil, inspired by the way musical notes are arranged, theorized that multiple frequencies could be used to send a single radio transmission. “Frequency hopping” could prevent a radio signal from being jammed. They patented the idea and gave it to the U.S. government for use in World War II, but it was largely ignored and the patent eventually expired.
Four decades later, Qualcomm saw potential for CDMA in the emerging cellular field. Founder Irwin Jacobs claimed it could increase capacity forty-fold, working so efficiently that wireless could become affordable for all. But the industry had invested millions in TDMA (time division multiple access) and was reluctant to change course. Some argued that CDMA was too complex and expensive to deploy. Others said it just wouldn’t work.
“CDMA has a long history of people saying, ‘It will not work,’ and we always had to say, ‘We know it works.’”
— Chuck Wheatley, Senior Vice President of Technology, Qualcomm Technologies, Inc.
To understand the difference, it’s important to know a little about the two technologies. TDMA sends multiple transmissions over a single radio wave by taking advantage of natural pauses in speech. In CDMA, each call is assigned a code that’s scrambled over a wide-frequency spectrum and reconstructed at the receiving end. Multiple users can speak at the same time, allowing more conversations to be delivered on the same amount of spectrum.
Proving CDMA’s viability for cellular posed many challenges, but Qualcomm persisted. Early on, they invited PacTel to a mobile demonstration, proving that CDMA worked while driving their new ally around San Diego in a white van. In 1989, the two companies demonstrated their findings to the industry. Though a small system failure threatened to capsize the event, the technology came out on top.
Qualcomm spent years performing field trials, drive tests, and industry demonstrations to prove not only that CDMA would work, but that it would work anywhere. Jacobs’ team focused on innovating infrastructure, air interfaces, chipsets, and handsets. Their relentless efforts paid off: in 1993 CDMA was accepted as an industry standard. In 1995 it was rolled out commercially for the industry-wide migration to 2G, ultimately becoming the foundation of all 3G networks worldwide and helping define the latest 4G and 5G technologies.
As the Internet became more prominent, CDMA prevailed as the best technology to handle the new demand for mobile broadband. It has revolutionized mobile computing, influencing other evolving technologies and changing the way we communicate and manage our daily lives. CDMA has also made worldwide mobile use possible, with the latest version surpassing Jacobs’ capacity predictions.
CDMA’s success established Qualcomm as an industry leader that benefits humanity by contributing innovations to the global tech ecosystem. The company not only leads in intellectual property that provides the basis for 3G, but also 4G, the even faster and more robust next generation of technology that will support massive traffic increases in coming years—just one example of how the future-forward approach that began with CDMA continues to guide Qualcomm today.