The
first analog cellular system widely deployed in North America was the Advanced Mobile Phone System (AMPS).[20] It was commercially introduced in the Americas
in 1978, Israel in 1986, and Australia in 1987.
AMPS was a pioneering
technology that helped drive mass market usage of cellular technology, but it
had several serious issues by modern standards. It was unencrypted and easily
vulnerable to eavesdropping via a scanner; it was susceptible to cell phone
"cloning;" and it used a Frequency-division multiple access (FDMA) scheme and required significant amounts
of wireless spectrum to support. Many of the iconic early commercial cell
phones such as the Motorola DynaTAC Analog AMPS were eventually superseded by Digital AMPS (D-AMPS) in 1990, and AMPS service was shut down
by most North American carriers by 2008.
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