History of the Cordless Phone

Telephone technology has certainly changed a great deal in the last twenty years. The improvement and technology of the telephone continued with invention of the cordless phone. Cordless phones were first introduced in 1980, but they operated on such a low frequency of 27 MHz (mega-herz) that it caused a limited range, noise, and static. Plus security was another issue where people could easily intercept signals from another cordless phone due to an inadequate number of channels. In 1986, the frequency range was increased to 47-49 MHz included less interference and power to run, yet range and sound quality remained poor. Digital cordless phones became available in 1994 with a frequency range of 900 MHz, which improved clarity and radio scanners could no longer pick up other conversations. By 1995, the development of digital spread spectrum (DSS) technology showed a new way of sending signals from the base to the handset. This enabled digital information to be spread into pieces over several frequencies and completely solved the interference problem. The only problem was they were very expensive, anywhere from $400 to $500 a piece, and had a limited number of choices. Between 1998 and 2003 the frequency range increased from 2.4 GHz to 5.8 GHz and expanded the operating distance. By 2000, the cost of cordless phones decreased to under $100.
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