While wireless phones have made their public debut in 1980, their design prior to this date more than a decade. In the early 1960’s an inventor named George Sweigert working on a model that will eventually lead to a patent. During the First World War, he served as a radioman in the South Pacific. During her watch, Sweigert a system of radio signal transmission, which will greatly improve communications in the field. After the war he developed this technology. In 1966, he presented his project in the U.S. Patent Office, which granted him a patent in 1969.

Early models Sweigert was built on a full duplex wireless concept, which is leveraged two-way radio transmission. This eventually lead to the introduction of a wireless phone.

In this article we describe the introduction of cordless phones and early limitations that affected them. We also look at how the Federal Communications Commission (FCC) agreed to the original problem. Finally, we briefly explain the emergence of new wireless technology called Digital Spread Spectrum.

Early adopters and with limited functionality

One of the first models were Cordless Carterphone. It is simplistic, but serves as a favorite for the industry. By the beginning of the 1980 major companies such as Sony Electronics has begun volume production of better design. Unfortunately, these early models could only operate at a frequency of 27 MHz.

Low frequency was extremely limited; signal clarity was poor, especially if the man was surrounded by other electronics. Another problem, at 27 MHz is the lack of confidentiality. It was pretty easy for other countries with cordless phones to eavesdrop on conversations over time, there are several available channels.
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