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Rebanding

From The RadioReference Wiki

Rebanding (also called Reconfiguration) refers to changes to the 800 MHz band plan that is taking place nationwide. Detailed information about rebanding can be found at http://www.800ta.org, but this page gives a brief overview and basic FAQ's. Note that some concepts have been simplified for brevity...if you have the time, feel free to edit the below to include more complete details.

History

When the 800 MHz band was originally created. Two segments of the spectrum were set aside for Cellular Telephone. Public Safety was assigned a set of frequencies, and "SMR" and "ESMR" services were allowed on the remainder of frequencies. However, unlike in other bands where licensee types were allocated to contiguous blocks of frequencies, in the 800 MHz band, Public safety, SMR, and ESMR services were all mixed together. This has resulted over time in situations where relatively low-power public safety channels (typically 125 - 300 Watts) are adjacent to relatively high-power ESMR services (up to 3kW). When a 3kW channel is next to a 125 W channel in the same geographic area, it is almost impossible for the 125W channel to be free of interference.

In the late 1990's, the FCC realized that they had a problem. The number of interference complaints were rising, and the popularity of the ESMR services that were primarily blamed for the interference was also rising, with no end in sight. Something had to be done. The FCC solicited input from the various users groups to determine the best course of action. Over the course of many hearings, replies, counter-replies, and conferences, the FCC has issued a Report and Order directing the "rebanding" of the 800 MHz spectrum. The result of the rebanding will be a contiguous block of frequencies reserved for Public Safety and a separate contiguous block reserved for SMR/ESMR.

So, where does Nextel come into this?

Nextel, contrary to popular belief, is not a cellular telephone company. They operate an "Extended (or Enhanced) Specialized Mobile Radio" service (ESMR). It does look like a cell phone, and it operates like a cell phone...but it really isn't. It is a business radio with telephone interconnect, and does not operate in the "cellular telephone" part of the 800 MHz spectrum.

As the largest licensee of ESMR channels, they are also responsible for the largest number of interference complaints to public safety.

What does rebanding actually do?

(To keep it simpler, I'm only discussing the high-power output side of the systems. The input side will be similarly reorganized as shown in the graphic.)

Before rebanding, Public Safety and ESMR's both operate in the 851 - 861 MHz range. ESMR has exclusive use of the 861 - 866 MHz range, and Public Safety has exclusive use of the 866-869 MHz range.

After rebanding, Public Safety will have exclusive use of the 851 - 854 MHz range. ESMR's will have exclusive use of the 862 - 869 MHz range, and both public safety and low-power SMR's will share the 854 - 860 MHz spectrum.

This is shown graphically here: img_channel_lrg.gif

Continued in the next section...

Why won't my scanner work after rebanding?

Well, depending on what you listen to, it might work. If you listen to EDACS or LTR (or conventional), you will just need to reprogram the new frequencies and logical channel numbers. However, if you listen to Motorola analog systems (which still comprise the largest number of public safety systems), your scanner will have a problem.

As part of the original spectrum allocation, each "slot" that public safety could operate on was assigned a channel number. Channels 1-120 were each 25 kHz apart, and started at 851 MHz.

Now, after rebanding, this part of the spectrum will have channels that are only 12.5 kHz apart.

Scanners track Motorola systems by monitoring the control channel. When the scanner detects a TGID that the user has programmed in, it gets from the control channel the channel assignment for the communications, then jumps to that frequency. At no time does the control channel actually pass the frequency information...just the FCC Channel assignment.

So, today if the scanner is told to go to Channel 66, it calculates the frequency as (851 + 66 * 25 kHz) and jumps to 852.65 MHz. After rebanding, the scanner will perform this same calculation and jump to that same frequency. The problem is...since the channel spacing has changed (from 25 kHz to 12.5 kHz), the new Channel 66 is on 851.825 MHz.

Even if you enter in all of the frequencies for the system, the scanner still relies on the above calculation and will miss the comms.

How will my scanner work after rebanding?

Well, now we get real fuzzy. Since no system has, at the time I'm writing this, been rebanded, no one knows what Motorola will do to their control channel. They could:

1. Just change their channelization and make no other changes to the data.

2. Use the control channel format used for P25 systems.

3. Use a completely new control channel format specifically for rebanded systems.

4. Something else...??

In all cases, the Uniden Scanners that are expected to support rebanding will require a firmware update that the user will be able to apply themselves.

For Radio Shack Scanners, it looks like only the scanners that allow for extended tables will operate, and then only if option 1 is used. If the change involves options 2-4, it looks like the only way the scanner will work is if RS sets up a board-exchange program to swap out the logic board with one that has the rebanded code installed.

It should be understood, though, that any of these options could require substantial analysis in order to determine the new format...not a 1 or 2 day job! The new format has to be derived, then tested thoroughly before public release. I would expect it to take up to 3 or 4 months from the time the first system goes live until any firmware updates become available. Perhaps longer if any bad surprises are encountered...

When will rebanding happen?

Depending on where you live, rebanding will happen some time within the next 3 1/2 years. The schedule is:

img_usmap_lrg2.gif

img_schedule_lrg.gif

Public Safety is what is referred to as "NPSPAC" in the above timeline. Note that the New Orleans area and other areas affected by Hurricane Katrina have been moved into Wave 3.

Rebanding Resources

Public Safety and 800MHz Reconfiguration:

Public Safety rebanding needs are unique with regards to the critical nature of Public Safety Communication. One of the most important pieces of the rebanding puzzle is how to manage the entire process while capturing information that needs to be auditable to support reimbursement. Some of the methods prescribed to answer this problem includes, creating Excel workbooks, Access databases, or paper forms. The problem with all these methods, aside from they require tremendous work on part of the incumbent, is they do not allow for Real Time monitoring of the rebanding process. However there is one company, http://www.mcmtechnology.com/, that has been in the communications industry since the early 90’s and has several different asset management software products. One product is specifically designed for communication service shops, managing service done on communication assets, tracking records like asset information, service information, billing information, and more. MCM Technology also claims to have a special addition of its software, specifically tailored to manage the rebanding process, generating all the auditable reports needed. This may be a resource many Public Safety Communication Officials find significant.


Answers to FAQ

The below answers are for the most common questions and misconceptions regarding rebanding.

1. This has nothing to do with 700 MHz.

2. This has nothing to do with cellular telephones.

3. No one knows anything for sure. Until a system is rebanded, anything you read that says "This is absolutely how it will be" is speculation (this article, included). However, you can check with the Transition Administrator's site to get the best educated guess of how your local systems may or may not be affected. First, get the callsign(s) for each of your local 800 Mhz trunk systems. Next, go to this site: http://www.800ta.org/content/800mhz/tools.asp - and select the Callsign Checker application. When you plug in each call sign, a chart will appear telling what rebanding steps, if any, are required. Some systems may require very few if any changes, and some may require more than others. If in doubt, check it out.

4. NEXTEL is paying for the costs of rebanding. However, they are only required to compensate licensees. Scanner users aren't typically licensees, so the cost of creating new firmware, replacing scanners, or reflashing scanners will be borne by the scanner manufacturers and hobbiests.

5. In exchange for paying the costs, NEXTEL is getting RF spectrum in the 1.8 GHz range.

Latest Updates

August, 2006: Trenton NJ (WPGP231) and Bethlehem PA (WNWQ636) have both submitted applications to the FCC for rebanded frequencies. These appear to be the first such application submitted for Motorola systems that require new channel assignments. Rebanded systems for Public Safety will be shown as being in Radio Service "YE"

2/22/2006: Motorola completes Firmware ahead of schedule (firmware for Motorola controllers and subscriber units to implement rebanding coverage). Inside the 1Q2006 TA Report, Page 10: [1]

2/14/2006: UCAN gets TA Funding, officials anticipate a complete frequency relocation agreement will be signed by June 30, 2006. Article from [2].