Safety Notice

Spotwave Wireless Inc.
45
Glossary
Cellular Handset
typical output
power
Ranges between approximately 50 to 600
mwatts
dB The difference (or ratio) between two signal
levels. Named after Alexander Graham Bell.
(That is why the "B" is capitalized. ) Used to
describe the effect of system devices on sig-
nal strength. For example, a cable has 6 dB
loss or an amplifier has 15 dB of gai n. This is
very useful because system gains and losses
can be calculated by adding and subtracting
dBi The gain a given antenna has over a theoreti-
cal isotropic (point source) antenna. Unfortu-
nately, an isotropic antenna cannot be made
in the real world, but it is useful for calculating
theoretical fade and System Operating
Margins.
A dipole antenna has 2.14 dB gain over a 0
dBi isotropic antenna. Thus, a simple dipole
antenna has a gain of 2.14 dBi or 0 dBd.