RF modules for cellular/PCS handsets
Keywords:pcs service? tdma? wireless design? cellular handset? rf module?
/ARTICLES/1999JUN/1999JUN29_BD_AMD_RFD_TAC.PDF |
17IIC-Taipei ? Conference Proceedings
RF Modules for
Cellular/PCS Handsets
Introduction
Similar to the explosive in the Internet services, demand for
Cellilat and PCS services has been growing by leaps and bumps.
As a result, from 1997 to 1998 worldwide handset production
increased from 110 millions to 160 millions and the forecast
for 1999 is close to 200 millionds.At that rate, handset produc-
tion will out-run PC production by a factor of almost 2 to 1 this
year.
There are serveral driving forces:
? Cost of service is getting cheaper every year
? Quality of service is better with new digital GSM, CDMA
andTDMA air interface standards than the older analog stan-
dards
? Handsets are getting smaller, lighter and more feature rich
evey six months
A state-of-art handset measures less than 3-4 inch long and
weights less than 4-5 ounces and provides the following fea-
tures:
? Dual or triple frequency bands
? 4.5 hours talk time
? 200 hours standby time
? Phone book with more than 250 names
? Conference calls
? Call hold/Call wait
? Alternative line service
? Automatic world clock
? Two games, Tetris and
Solitaire
? Easy access to the 20 lat-
est numbers dialed, calls
received or missed
? Advice of charging
? Fixed dialing numbers
? Call baring
? Calling line identification
? SIM application tool kit
The competetive bat is
raised every time a major
handset supplier introduces a
new model.
To meet the challenges,
handset manufacturers
demand more and more from
Dr. Charles Huang
ANADIGICS, Inc.
their component supplier. For radios, the Holy Grail si "Radio
on a Single Silicon Chip".
As much as it's desired, "Radio on a Single Silicon
Chip"is not technically feasible because
? 110 DB selectivity requires passive filters such as SAW or
dieletctric filters
? Long talk time requires GaAs power amplifiers and switches
As a result, multi-chip modules (MCMs) which integrate
differebt type of chips inside a single mechnaical housing be-
come an attractive alternative.
RF modules for handsets
In figure 1, a CDMA PA module is presented. The module in-
corporates GaAs IC, silicon transistor, chip resistors and ca-
pacitors. It delivers 29 dBm output power at PCS frequencies.
In figure 2, a SAW receiver module is presented. The mod-
ule incorporates GaAs ICs and surface acoustic wave (SAW)
filters and deliver superior performance for handset receivers.
Summary
RF module deliver optimal solutions for state of the art hand-
sets.
Figure 1: A CDMA PA Module
18 IIC-Taipei ? Conference Proceedings
Figure2: A SAW Receiver Module
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