directions; first from higher to lower, then vice-versa.
employ the proper antennas and they must be properly oriented. When
two or more systems use the same site, frequency separation between
the transmit and receive antennas becomes a critical consideration.
Part B of this lesson discusses frequency assignment and frequency
c. System Flexibility. Multichannel radio systems provide a wide
variety of communications capabilities.
Some of the capabilities
include the following:
rear, or lateral positions before HQ, and establish a
They monitor the old CP and switch circuits to
the new CP
before the old CP closes.
(2) You may integrate multichannel radio links and relays into
cable systems without reducing their capabilities. These radio links
span dense forests, swamps, jungles, rivers/lakes, etc., where cable
system construction is impractical.
(3) Through proper arrangement of equipment, you can reroute
channels, without termination, over forward or lateral area systems.
This procedure, known as "strapping through," provides point-to-point
circuits over systems normally used for trunk service.
(4) You may arrange relay equipment to serve as multichannel
terminal stations when sufficient terminal equipment is unavailable.
This requires the use of additional multiplexing and ringing
PART B - FREQUENCY PLANNING
the radio frequency spectrum available. The RF spectrum extends from
3 kHz to 300 gigahertz (GHz) and is internationally controlled. The
nations of the world meet periodically to permit equitable sharing of
the spectrum on a worldwide basis.
As an S3 officer, several sets of rules govern your use of these
The following paragraphs discuss frequency
management down to the U.S. Army level.
The international telecommunications union
(ITU), a special agency of the United Nations, is the international
frequency manager. They make regulations on the