(Personal Communications Services)
1. The FCC-licensed frequency band near 1900 MHz.
Like most bands used for cellular phone service, PCS is a paired band, meaning towers transmit to phones at one frequency, while phones comunicate to towers on a different frequency.
Also like most bands used for phones, the PCS band is divided into smaller "blocks", which may be licensed by different companies in any given area.
The original PCS band consisted of six blocks, spanning 1850 - 1990 MHz. These were used for a variety of 2G and 3G technologies, including TDMA, GSM, CDMA, and later, WCDMA and LTE.
In 2004, the FCC granted Sprint the use of a seventh block - block G - that includes 1910-1915 and 1990-1995 MHz. This new block was used for Sprint's initial deployment of LTE technology.
In the context of WCDMA and LTE networks, the standard PCS band is also known as band 2 (II). The expanded PCS band used by Sprint - including block G - is known as band 25. In the context of CDMA networks, the PCS band is known as BC1, which stands for band class 1, and the expanded band, with the G block, is BC14.
2. PCS is also a marketing term used to describe a wide variety of two-way digital wireless service offerings operating at 1900 MHz.