Wired communications can be traced back to 1844, when Samuel Morse (creator of the code of dots and dashes that bears his name) sent the first telegraph message from the U.S. Supreme Court chambers in Washington, D.C. to the Mount Clair railway depot in Baltimore, Maryland. Fourteen years later, the first transatlantic telegraph cable was completed. Alexander Graham Bell’s famous first telephone call transformed communication again, moving from dots and dashes over the wires to voice. The first telephone line was set up in 1877 in Boston, Massachusetts, but it wasn’t until 1956 that the first transatlantic telephone cable was launched. As wired communications have continued to advance, semiconductors are playing an important role in enabling the new technologies that keep us connected.
In recent decades, wireless technology has revolutionized the communication industry, with mobile subscriptions predicted to reach 8.9 billion in 2022. However, wired communications still have several advantages over the wireless world. Wired communication is faster for transferring large amounts of data and generally considered more stable and impervious to weather conditions. It doesn’t suffer the problems of signals being weakened by obstacles or dropped altogether, and it’s also considered more secure than wireless, where signals can be easily jammed or hacked. Many corporate environments, while integrating more wireless communication, still use wired networks for security reasons. Wired is also widely used for cable television and internet services.
Devices used in wired communications include Ethernet controllers (for networks), adapters, and switches. They also include Power over Ethernet (PoE) interface controllers that support Voice over Internet Protocol (VoIP) and powerline transceivers. For many years, copper – which transmits electrical current – has been the material of choice for telephone lines, but increasing amounts of data being created and transmitted have created problems with speed. To increase bandwidth in wired communications, fiber optics are on the rise.
Fiber optic technology transmits pulses of light generated by a light-emitting diode (LED) or laser along fiber optic cables that use special glass as thin as a human hair. A transmitter converts electronic information into pulses of light that are then converted back to information by an optical receiver containing a photo detector (normally a semiconductor device). Optical fiber can carry much higher frequency ranges than copper cable, which means greater bandwidth. Wavelength-division multiplexing (WDM) allows multiple optical carrier signals on a single optical fiber by using different colors of light to transmit the signals. Not only is optical fiber faster than copper, it can also carry information over greater distances and is less susceptible to noise and electromagnetic interference.
Traditional public-switched telephone networks are already being abandoned by consumers in favor of digital telephony and VoIP services, whether over cable, high-speed mobile networks, or via internet services such as Skype. Unified communication solutions integrate voice, video, messaging, and presence services (showing whether you’re available and through what means of communication) into one platform. While wired is still in play today, there’s no doubt that the mobility enabled by wireless technology will continue to grow.
Whether wired or wireless, semiconductors are an integral part of communications technology, from network connectivity, base stations, and routers to phones, laptops, and other connected devices – even the sensors that gather and transmit data. The needs of these segments will shape the expectations of chipmakers and drive demand for semiconductor innovation for years to come.