Computing power can mean many things depending on where
the term is applied. The computing power of today’s cellular
handset is much greater than just ten years ago. The mobile
phones of the 1980s used 8-bit microcontrollers with very little
memory. A typical phone operated with 6 Kb of RAM
(scratchpad memory) and 32 Kb of ROM (program memory).
That was fine, because AMPS was an analog communications
system based on FM and the data rate was low because all data
requires a modem to convert digital data to analog modulation.
Data rates for wire-line modems in the early 1980s were initially
300 baud progressing to, at best, 19,200 baud by 1990.
Therefore, rates of 1200 baud to 2400 baud were acceptable
for wireless device communications. (One important point
should be noted—gross baud rates and throughput are two different
things entirely!)
The wireless cellular communications channel is a dirty,
nasty place for data communications signals. Impairments to an
analog cellular channel are noise, weak signals, interference,
and signal dropouts caused by handoffs from one channel to
another. Today’s digital cellular channel problems are compounded
by signal degradation, multipath fading, and delay.
But today’s cellular phones have more computing power
than the average workstation of the early 1990s. They will contain
16-bit, 32-bit, or 64-bit RISC microcontrollers, digital signal
processors capable of 400 MIPS or more by 2002, and they
will contain megabytes of memory. This translates to computational
power sufficient to make a digital voice call or send highspeed
data such as full motion video while simultaneously
reading your email on the display. Data rates will soon
approach ISDN or DSL rates and may go higher, anywhere
from 114 Kbps to 2 Mbps or higher.
This vastly increased computing power (and the interest of
the Defense Department) has brought one other very important
new feature to wireless communications devices—Global
Positioning Services (GPS). Using GPS, a wireless device can
communicate its location to anywhere in the world. Orwell
look out: Location-based marketing to a mobile customer base
is coming.