As with all the material on the forum, use this information at your own risk.
This spreadsheet uses a drop-down band selector under the SELECT BAND column and will allow a maximum of 12 bands to be selected.
After the band(s) are selected from the drop down SELECT BAND column (multiple rolls, one band per roll), an AT!Command is automatically generated that defines each band selected as well as the GROUP that makes up those bands.
Locking bands can be an important tool for optimizing performance. For example, let's say a Sierra Wireless MC7455 modem in a router has a tendency to camp out on Band 12 which only shows to have 5HMz of bandwidth, and while Band 12 has great signal strength (according to the stats), is not a good performing Band.
One variable to always consider is the frequency assigned to a particular Band. Band 12 in our example expands the lower 700MHz frequency. It is important to understand that different frequencies have different characteristics.
The higher the frequency (e.g., Sprint Band 41 at 2496-2690MHz), the shorter its wavelengths, the lower its energy, and the more sensitive its waves are to reflection and material absorption. This means the higher frequencies are more challenged over distance and penetration of trees, buildings and other obstacles (which absorb the signals) than the lower frequencies (e.g., AT&T Band 12 at 700HMz)—which have longer wavelengths, more energy and deeper penetrating power with less absorption.
You may understand in our example above why the modem prefers Band 12 (with 5MHz) over a different band that may have 20HMz of bandwidth to offer. Most modems will generally select its primary band based on signal strength. And, stronger signals does not always equate to better performance. Likewise, the closest cellular tower is not always the best tower to optimize the performance of a device.
This may also be compounded in certain wooded terrain where other cell phones, hotspots and routers are also camped out on Band 12 for the same reasoning. Thus, tower congestion may comes into play as more and more people are utilizing Band 12 (because of its penetrating power) and the network's resources are strongly taxed on that band.
One way to address this issue is to prepare a Group (or a couple of Groups) of bands that precludes Band 12 or any other undesirable bands.
UPDATED: 11-02-2019
[*]Corrected the L Mask's removal of Zeros (Thanks to patman2 for pointing out the error)
UPDATED: 10-29-2019
[*]Updated Verizon's use of Band 13
UPDATED: 10-02-2019
[*]Updated the Comments (instructions) in the Cells
[*]Removed leading 0's from the bands
[*]Extended support for the MR1100 (M1)
[*]Included AT command to remove group of custom bands
UPDATED: 09-25-2019
[*]Corrected MC7455 to include Band 30
[*]Includes Carriers vs Bands vs Modems
[*]Added Frequencies for Selected Bands
Prior to programming a band it is best to use the authorization command:
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AT!ENTERCND="A710"Once the bands are programmed, a reboot of the modem is required:
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AT!RESETYou will also notice on the far right top whether the bands selected are included in some more common Sierra modems. This will help avoid attempting to program a band that is not compatible with a specific modem. A review of this selection shows these bands available for MC7455 (and the EM7455 which I just noticed I excluded).
In the example, to program bands 25 and 41 we may first to define and id those bands using the following AT Commands (copy and paste). While it is necessary to define each band individually to create a group, it will allow locking later to a single band that we used in the group :
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AT!ENTERCND="A710"
AT!BAND=10,"B25",0,0000000001000000
AT!BAND=11,"B41",0,0000010000000000Notice on the bottom under CUSTOM BAND GROUP, I named this GROUP of two bands as "Sprint 25-41". Therefore, I need to program this group as well:
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AT!BAND=0F,"Sprint 25-41",0,0000010001000000In order to set and restrict the modem to using only this GROUP of bands we use the SET GROUP - AT COMMAND:
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AT!BAND=0FCombining these AT Commands, we get:
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AT!ENTERCND="A710"
AT!BAND=10,"B25",0,0000000001000000
AT!BAND=11,"B41",0,0000010000000000
AT!BAND=0F,"Sprint 25-41",0,0000010001000000
AT!BAND=0F
AT!RESET
Now lets assume we want to restrict the modem to only use the band 41 as we defined above. We would use the SET BAND - AT COMMAND that corresponds to Band 41:
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AT!ENTERCND="A710"
AT!BAND=11
AT!RESET
Note that these bands are hard coded into the modem and will persist following a modem reboot or swapping it into another device.
In order to reassign the bands or group of bands we must redefine the bands, or restore the modem to OEM, or instruct the modem to receive ALL bands (00)--which may be accomplished with the following command:
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AT!ENTERCND="A710"
AT!BAND=00
AT!RESET
One other note is that all the current available bands are included in the spreadsheet. To add a band to a group, Click on the cell under the BAND SELECT and select the band number from the drop down to be included:
At the top of drop down of the BAND SELECTION, there is a blank selection to use when a band is not to be included.
It may also be useful to list what bands are available on a particular Sierra Wireless modem:
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AT!ENTERCND="A710"
AT!BAND=?We hope to extend the spreadsheet to cover other makes and models of modems. Members are free to submit revisions.
