TS4000 Radio Modem User’s Manual
Licensing
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Licensing
To be operated legally, radio equipment requires two types of licensing - a
manufacturer’s certification that the manufacturer obtains and a users license
that the user must obtain.
In most cases, the user of the TS4000 is required to obtain an operating license.
This is the case for most frequency ranges in most areas of the world. Licensing
is done so that the government can coordinate radio users in order to minimize
interference. There are a handful of unlicensed frequency in the VHF band that
are available for use in the United States (see Unlicensed Operation below).
User’s License
It is the user’s responsibility to obtain the necessary licenses prior to
transmitting over the air with the TS4000.
The user is also responsible for
proper setup, operation, and maintenance of the TS4000 so that it complies with
the limits specified by the license.
Changes or modifications not expressly approved by Teledesign Systems
Inc. could void the user’s authority to operate this equipment.
Shielded cable must be used with this equipment in order to ensure that it meets
the emissions limits for which it was designed. It is the responsibility of the user
to obtain and use good quality shielded interface cables with this device.
Shielded interface cables are available from most retail and commercial suppliers
of interface cables designed to work with personal computer peripherals.
Within the different frequency bands (i.e. VHF, UHF, 900 MHz etc.) channels are
licensed with a specific channel spacing (i.e. 25 kHz, 12.5kHz, etc.). The
channel spacing corresponds to the difference between the center frequencies of
adjacent channels. The TS4000 can be ordered with various channel spacing
options.
Channel Spacing and
Occupied Bandwidth
For each frequency band and channel spacing, there is a corresponding
maximum occupied bandwidth. The maximum occupied bandwidth is the
amount of frequency bandwidth that the user on a channel is allowed to occupy.
This is typically (but not always) less than the channel spacing in order to
minimize interference between users on adjacent channels.
The occupied bandwidth of the TS4000 can be configured by the user (see
Radio Setup). The occupied bandwidth must be set to a value less than or equal
to the maximum allowed occupied bandwidth of the channels that the user is
operating on. Note that the setting of occupied bandwidth limits the maximum
over the air data rate that the TS4000 can operate at. The maximum over the air
data rate is also dependent on the modulation type selected.
For each TS4000 there is a maximum occupied bandwidth that cannot be
exceeded and is dependent on the bandwidth of the specific radio module that
the unit was ordered with. This maximum occupied bandwidth is configured
when the unit is manufactured and cannot be changed by the end user.
Within the US, the FCC indicates the maximum occupied bandwidth as part of
the channel emission designator. For example, an emission designator of
16K0F1D corresponds to a 16.0 kHz occupied bandwidth. The emission
designator of the licensed channel or channels shows up on the license form that
is received when the FCC (or other appropriate licensing agency) grants a
license.
