PACS (Personal Access Communications Services)

A digital cordless telephony total system stan-

dard that addresses both the air interface and network infrastructure. A modification of the WACS (Wireless Access Communication System) specification, PACS was developed in the U.S. for licensed Personal Communications Services (PCS) applications, although several unlicensed versions exist as well. The licensed version of PACS employs frequency division duplex (FDD) to support downstream transmission in the 1930–1990 MHz band and upstream transmission in the 1850–1910 band, with channel spacing at 300

kHz. Each channel will support a data rate of 384 kbps with µ/4 quaternary phase shift keying (µ/4 QPSK) as the modulation technique. Each RF channel supports seven users through time division multiple access (TDMA).Voice encoding is adaptive differential pulse code modulation (ADPCM) at 32 kbps. See also ADPCM, air interface, channel, cordless telephone, digital, downstream, encode, FDD, modulation, PCS, µ/4 QPSK, TDMA, and upstream.

• 16
• 16-QAM
• 16-QPSK
• 18
• 1:8 Splitter
• 1A
• 1A1
• 1A2
• 1Base5 (1 Mbps; Baseband; 500 meters)
• 1B+D
• 1. Domain Name System. The naming convention that divides the Internet into logical domains identified in Internet Protocol version 4 (IPv4) as a 32-bit portion of the total address.The standard convention is user@organization.domain, where user is the name of the end user, organization is the name of the enterprise or other organization owning or sponsoring the address, and domain is the type of entity owning or sponsoring the address.The administration of the DNS is the responsibility of Internet Corporation for Assigned Names and Numbers (ICANN). See also domain, ICANN, Internet, and IPv4. 2.
• 1. In storage, irrelevant material, usually zero (0) bits, added to a data block in order to fill it to a minimum size, to force certain fields of control data or user data into certain positions or sizes, or to prevent the user data from duplicating a bit pattern that has a specific control meaning. See also block. 2.
• 1 cps, 1 Hz
• 1+ Dialing
• 1G (1st Generation)
• 1G (1st Generation)
• 1-persistent carrier sense multiple access (1-Persistent CSMA)
• 1-Persistent CSMA (1-Persistent Carrier Sense Multiple Access)
• 1+ WATS
• 1xEV-DO (one carrier EVolution-Data Optimized)
• 1xRTT (one times Radio Transmission Technology)
• 2
• 20
• 2:1
• 2:1