Instructions
To create a channel plan, set the various data for the first frequency band to
use. Next select the channels.
There are two ways to set the frequency band data; enter the data in each
input field, or select the frequency band from the selection box if you
already know it.
 Setting the frequency band data
1. Using the selection box
If you use the "Band selection" box, you can set the representative frequency
band for each country. When you set the frequency band, the starting channel
and channel span are set automatically.
2. Entering data in the data input field
Enter the channel number of the frequency band for the country in which you
are making a channel plan, and enter the corresponding frequency and channel
span. After entering each item, press the "Enter"; key on your keyboard, or
click the "Initialize" button.
- "Staring channels" : Enter the starting channel number of the frequency band.
- "End channels": Enter the end channel number of the frequency band.
- "Starting frequency": Be sure to enter the frequency of the starting
channel.
- "Channel span" : Enter the channel separation determined by the
frequency band used.
- "Forbidden frequency bands" : The default is 1-fold. Select a suitable
value for the selectivity of the receiver.
- "Initialize" button: Initializes the display with the set value.
Selecting a channel
Click the checkbox of a frequency to select it.
- * Green: Selected frequencies are highlighted in green. Checked channels
shown in green are channels that can be used at the same time in the same
area.
- * Yellow: Indicates channels that may be affected by third-order
intermodulation interference or by the near-far problem. Do not use these
channels.
- * Red: Red indicates that third-order intermodulation interference will
occur between channels. If a channel is shown in red, click the checkbox
again to deselect it, and choose another channel.
Miscellaneous
The Japanese 800 MHz frequency band
With Japan's 800 MHz frequency band, you can use the "Plan support" box. This
creates a channel plan automatically for the frequency band that you set. In
this case, the "Forbidden frequency bands" is just one adjacent channel.
If you select plan with "Plan support", distinguish between a plan where the
total number of channels in the frequency band width is 30 or less, and 30 or
more. If the plan is not created completely, check the unchecked items to
complete it.
About the near-far problem
In order to avoid the near-far problem, it is necessary to adjust the
frequency bands in the "Forbidden frequency bands". If the channels of
specific low power radio equipment with a narrow channel span (e.g., 12.5 kHz)
are not separated by several channels, mutual adverse effects may arise with
other radio equipment located a short distance away.
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