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Material Type: Notes; Class: Wireless Communications; Subject: Electrical & Computer Engr; University: Villanova University; Term: Spring 2005;
Typology: Study notes
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Yimin Zhang, Villanova University
ECE 8708 Wireless Communications : Introduction to Wireless Communication Systems
http://yiminzhang.com/ECE
Yimin Zhang, Villanova University
ECE 8708 Wireless Communications : Introduction to Wireless Communication Systems
Outlines^ Outlines
Yimin Zhang, Villanova University
ECE 8708 Wireless Communications : Introduction to Wireless Communication Systems
-^ Cellular phone users^1984 -^
-^
-^
-^
Yimin Zhang, Villanova University
Yimin Zhang, Villanova University
ECE 8708 Wireless Communications : Introduction to Wireless Communication Systems
Advanced Mobile Phone System. Developed by Bell Labs in the 1970s andfirst used commercially in the United States in 1983. It operates in the 800and 1900 MHz band in the United States and is the most widely distributedanalog cellular standard. AMPS
Analog Cellular TechnologiesDigital Cellular Technologies
Digital AMPS. Designed to use existing channels more efficiently, D-AMPS(IS-136) employs the same 30 kHz channel spacing and frequency bands(824-849 and 869-894 MHz) as AMPS. By using TDMA instead offrequency division multiple access or FDMA, IS-136 increases the numberof users from 1 to 3 per channel. An AMPS/D-AMPS infrastructure cansupport either Analog AMPS phone or digital AMPS phones. (The FederalCommunications Commission mandated that digital cellular in the U.S.must act in a dual-mode capacity with analog). Operates in the 800 MHzband and 1900 MHz. D-AMPS(IS-54,nowrolled intoIS-136)
Yimin Zhang, Villanova University
ECE 8708 Wireless Communications : Introduction to Wireless Communication Systems
Digital Cellular Technologies
Personal Communications Service. The PCS frequency band in America is1850 to 1990 MHz, encompassing a wide range of new digital cellularstandards like N-CDMA and GSM 1900. Single-band GSM 900 phonescannot be used on PCS networks. PCS networks operate throughout theUSA. PCS
Global System for Mobile Communications. The first European digitalstandard, developed to establish cellular compatibility throughout Europe.Its success has spread to all parts of the world and over 80 GSM networksare now operational. It operates at 900 and 1800 MHz in many parts ofEurope and in England. Works at 1900 MHz in some parts of the UnitedStates. TDMA based. GSM
Yimin Zhang, Villanova University
ECE 8708 Wireless Communications : Introduction to Wireless Communication Systems In 1990 North American carriers faced the question -- how do we increasecapacity? -- do we pick an analog or digital method? The answer was digital. InMarch
the^
North
American
cellular
network
incorporated
the^
standard,
the^
first^ North
American
dual
mode
digital
cellular
standard.
This
standard won over Motorola's Narrowband AMPS or NAMPS, an analog schemethat increased capacity by cutting down voice channels from 30KHz to 10KHz. IS-54 on the other hand increased capacity by digital means: sampling, digitizing,and then multiplexing conversations, a technique called TDMA. This methodseparates calls by time, placing parts of individual conversations on the samefrequency, one after the next. It tripled call capacity.Using IS-54, a cellular carrier could convert any of its systems' analog voicechannels to digital. A dual mode phone uses digital channels where available anddefaults to regular AMPS where they are not. IS-54 was, in fact, backwardcompatible with analog cellular and indeed happily co-exists on the same radiochannels as AMPS. No analog customers were left behind; they simply couldn'taccess IS-54's new features. CANTEL got IS-54 going in Canada in 1992. IS-54also supported authentication, a help in preventing fraud. IS-54, now rolled intoIS-136, accounts for perhaps half of the cellular radio accounts in this country.
Yimin Zhang, Villanova University
ECE 8708 Wireless Communications : Introduction to Wireless Communication Systems
Yimin Zhang, Villanova University
ECE 8708 Wireless Communications : Introduction to Wireless Communication Systems
Yimin Zhang, Villanova University
Yimin Zhang, Villanova University
ECE 8708 Wireless Communications : Introduction to Wireless Communication Systems
trans-ceiver <1 GHz moderate high high high Cellularphone
trans-ceiver <100MHz low moderate low low Cordlessphone
receiver <1 GHz low low high high Pagingsystem
trans-mitter <100MHz low low low low Garagedooropener
trans-mitter infra-red low low low low TVremotecontrol
Function-ality Carrierfrequency Hardwarecost Com-plexity Requiredinfra-structure Coveragerange
Yimin Zhang, Villanova University
ECE 8708 Wireless Communications : Introduction to Wireless Communication Systems
trans-ceiver <1 GHz high high high high Cellularphone
trans-ceiver <100MHz moderate low low low Cordlessphone
<1 GHz high high high high Pagingsystem
receiver <100MHz low low low low Garagedooropener
infra-red low low low low TVremotecontrol
Function-ality Carrierfrequency Hardwarecost Com-plexity Requiredinfra-structure Coveragerange Service
receiver trans-mitter
Yimin Zhang, Villanova University
Yimin Zhang, Villanova University
ECE 8708 Wireless Communications : Introduction to Wireless Communication Systems
-^ Full duplex communication•^ Few hundred meters
