Table 1-3.Decibel to Power Ratio
Table 1-4.Logarithms
receivers sensitivity drops to -107 dBm. Since a loss of
3 dB reduces the sensitivity by 1/2, the input signal will
have to be twice as large to be detected.
TRANSCEIVERS
A transceiver is a unit, usually enclosed in a single
case, that combines a transmitter and receiver using a
common frequency control. Transceivers are used ex-
tensively in two-way radio communications at all fre-
quencies, and in all modes.
The primary advantage of using a transceiver
rather than a separate transmitter and receiver is cost.
In a transceiver, many of the components can be shared
during both transmit and receive operations. Another
advantage is that transceivers can be tuned more easily
than separate units.
A disadvantage of using a transceiver is that
while duplex operation is not possible with most trans-
ceivers, communication must sometimes be carried
out on two different frequencies. Although this is a
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