Licensing MOTOTRBO on UHF T Band

[MassFD]

We all know that there was a stop on license mods to UHF "T" band (470 to 512) after the 700 MHZ public safety legislation passed. I have read about some modifications to licenses are now alowed but is an emisions mod to allow use of MOTOTRBO permitted?

It still looks like we will loose the use of T band sooner or later but MOTOTRBO would be a way to add 2 talk paths to 1 12.5 freq for now.

Can it be done??

[escomm]

Sure. Lots of it happening here in LA.

[thebigphish]

Same here in the philly area.

[escomm]

The general rule of thumb with T band licenses is that anything can be done to them that would not otherwise increase their coverage footprint.

[MassFD]

Thanks Guys, thats what I was hopeing to hear. So as long as I do not change power output I should be OK. How do these systems perform VS analog at the same power?

[Bill_G]

Coverage is about the same, but audio quality issues are the biggest complaint. If you have good mic technique, it's loud and clear. If the people talk at their lapel mic clipped to their shirt, it can get kind of mushy. Some customers get used to it, and some don't.

[FMROB]

The general rule of thumb with T band licenses is that anything can be done to them that would not otherwise increase their coverage footprint.

This is not entirely accurate. A change of emission due to the FCC freeze will be difficult if not impossible without a waiver of the rules (freeze of t band). The way that the LMCC, FCC, and coordinators are viewing it is as an expansion of spectral foot print going from analog to digital, both from a # of user standpoint and technical RF standpoint.

Other additional factors to consider is that you may be subject to produce an acceptable TSB88 study, which if you change from 11K to 7K could "possibly" push a marginal study over the edge. This depends on co or adjacent channel users. That would be more complicated if the other co/adjacent user are still wide band or 6.25 (treated as wide band for tsb calculations).

I have not seen or aware of any public safety T Band license changes from analog to digital post freeze here in NY?

Just my 2 cents.


For quick reference

"Effective immediately and until further notice, the Bureaus will not accept or process (1) applications
for new licenses; (2) applications that seek to modify existing licenses by adding or changing frequencies
or locations; (3) applications that seek to modify existing licenses by changing technical parameters in a
manner that expands the station’s spectral or geographic footprint, such as, but not limited to, increases in
bandwidth,2 power level, antenna height, or area of operation; and (4) any other application that could
increase the degree to which the 470-512 MHz band currently is licensed.3 We clarify that affected
applications that are now pending will not be further processed until the Commission decides how to
implement the Act, except that defective applications and applications in return status that are not timely
resubmitted will be dismissed.4
This action does not apply to applications that would not destabilize the licensing landscape,
including (1) applications to renew existing licenses without modification; (2) applications that seek to
modify existing licenses by deleting frequencies or locations; (3) applications that seek to modify existing
licenses by changing technical parameters in a manner that does not expand the station’s spectral or
geographic coverage, such as decreases in bandwidth, power level, or antenna height; (4) applications that
seek to modify existing licenses by changing the number of associated mobile units or temporary fixed
stations; (5) applications that seek to modify existing licenses by adding or moving control points; (6)
applications to assign, transfer, or lease existing licenses; (7) notices of construction or consummation; (8)
requests for extensions of time to construct or consummate previously granted applications; (9)
applications to cancel licenses; and (10) applications for special temporary authority for short-term
operations. The Bureaus may in the future begin placing a special condition on new, renewed, and
modified licenses for stations in radio services and frequencies subject to this action to remind licensees "

and

"PUBLIC NOTICE

Federal Communications Commission

News Media Information 202 / 418-0500
445 12th St., S.W.

Internet: http://www.fcc.gov

Washington, D.C. 20554

TTY: 1-888-835-5322

DA 12-892

Released: June 7, 2012

WIRELESS TELECOMMUNICATIONS BUREAU AND PUBLIC SAFETY AND HOMELAND

SECURITY BUREAU CLARIFY SUSPENSION OF THE ACCEPTANCE AND PROCESSING

OF CERTAIN PART 22 AND 90 APPLICATIONS FOR 470-512 MHz (T-BAND) SPECTRUM
On April 26, 2012, the Wireless Telecommunications Bureau and the Public Safety and
Homeland Security Bureau (Bureaus) issued a public notice announcing a limited suspension of the
acceptance and processing of certain applications for Part 22 and Part 90 services operating in the 470-
512 MHz spectrum band (T-Band).1 The Suspension Notice suspended the acceptance and processing of
T-Band applications that could alter the spectrum landscape in order to stabilize the spectral environment
while the Commission considers issues surrounding future use of the T-Band, solicits input from
interested parties, and works to implement the directives of the Middle Class Tax Relief and Job Creation
Act of 2012.2 By this Public Notice, the Bureaus clarify the applicability of the suspension with respect
to certain types of applications.
In the Suspension Notice, the Bureaus stated that the suspension applied to applications “that
would, if granted, tend to increase the degree to which the 470-512 MHz band is currently licensed” but
not to “applications that would not destabilize the licensing landscape,” and listed examples of both
categories.3 The Bureaus have received inquiries from interested parties seeking further guidance on
whether certain types of T-Band applications would or would not fall within the scope of the suspension.4
Accordingly, we offer the following clarifications:
·
The Suspension Notice stated that the suspension applies to “applications that seek to modify
existing licenses by adding or changing frequencies or locations.”5 We clarify that


1 Wireless Telecommunications Bureau and Public Safety and Homeland Security Bureau Suspend the Acceptance
and Processing of Certain Part 22 and 90 Applications for 470-512 MHz (T-Band) Spectrum, Public Notice, DA 12-
643 (WTB/PSHSB rel. Apr. 26, 2012) (Suspension Notice).
2 Suspension Notice at 1-2. See also Pub. L. No. 112-96, 126 Stat. 156 (2012) (Act). Section 6103 of the Act
provides that, not later than nine years after the date of enactment, the Commission shall “reallocate the spectrum in
the 470-512 MHz band … currently used by public safety eligibles ….” Id., § 6103(a). The Act instructs the
Commission to “begin a system of competitive bidding under Section 309(j) of the Communications Act of 1934 (47
U.S.C. 309(j)) to grant new initial licenses for the use of the spectrum.” Id. It also provides that “relocation of
public safety entities from the T-Band Spectrum” shall be completed not later than two years after completion of the
system of competitive bidding. Id., § 6103(b), (c).
3 See Suspension Notice at 2.
4 See, e.g., Letter dated May 8, 2012 from Mark E. Crosby, President, Enterprise Wireless Alliance (EWA), to David
Furth, Acting Chief, Public Safety and Homeland Security Bureau, and Rick Kaplan, Chief, Wireless
Telecommunications Bureau (EWA Letter); Motorola Solutions, Inc., Ex Parte, WT Docket No. 99-87 (filed May
22, 2012).
5 See Suspension Notice at 2.

applications that seek to add or change locations are suspended only if the new location
extends the station’s authorized interference contour in any direction. Locations may be
added or changed if the new site does not increase the licensed contour.
·
We further clarify that the suspension applies to any application that seeks to add a new
channel to the authorization, whether the channel is a replacement or is being added to
existing channels.6 As noted above, the purpose of the freeze is to stabilize the existing
spectrum landscape. Allowing licensees to alter their active frequencies in the T-Band would
be inconsistent with this purpose and would lead to an unpredictable and unstable spectral
environment. This approach is consistent with prior filing and processing suspensions.7
·
The Suspension Notice stated that the suspension included “applications that seek to modify
existing licenses by changing technical parameters in a manner that expands the station’s
spectral or geographic footprint.”8 We clarify that applications that seek to add or change an
emission type (the last three characters of the emission designator) are suspended only if the
licensee also proposes to increase the authorized bandwidth. Emission types may be added or
changed so long as the emission remains within the existing authorized bandwidth, even if the
new emission type nominally expands the station’s spectral footprint.9
·
The Bureaus stated that the suspension did not include “applications to renew existing
licenses without modification.”10 They also stated that applications requesting a modification
the processing of which has been suspended will be dismissed.11 We now clarify that a
renewal/modification application filed during the filing and processing suspension that
requests such a modification will be granted-in-part only with respect to the request for
renewal.
Parties whose applications are subject to the filing and processing suspension, as clarified above,
may seek a waiver of the suspension pursuant to Section 1.925 of the Commission’s rules.12. Parties
seeking a waiver must provide a showing that they meet the waiver criteria in Section 1.925.
For further information, contact the FCC ULS Customer Support Hotline at (877) 480-3201
option 2, (717) 338-2888, or (717) 338-2824 (TTY). The Hotline is available to assist with questions
Monday through Friday 8:00 a.m. to 6:00 p.m. ET. In order to provide better service to the public, all
calls to the Hotline are recorded.
Action by the Wireless Telecommunications Bureau and the Public Safety and Homeland
Security Bureau.
-FCC-"

[FMROB]

as a side note

You will "notice" an increase in coverage whereby a once semi useable signal will now be full quieting so to speak. Your range increase comes where on the fringe part of the system where a user would normally fade or picket fence in analog will now be loud and clear in digital. So the range increase is perceived.

Rob

[MassFD]

Wow Rob, thats a lot to read.

As far as co or adjacent channel users, we have both the adjacent channels and that brings up another question.

How well will mototrbo get along with the analog adjacents on both sides that are also on the same site.

[Bill_G]

Adjacents on both sides at the same site?

How well do the three channels play together right now?

[FMROB]

On my blackberry, so I will try my best with my sausages.

If your adjacent channel users are narrow band, there shouldn't be much of an issue. I make that statement assuming they are not on the same site, and assuming all equipment is functioning properly and on channel. Different freqs on the same site poses a myriad of other considerations.

Co-channel users are a different story. They will no longer appreciate you as a neighbor of the same channel. The digital noise is annoying, and much harder to compete with than analog traffic.

For the purpose of licensing, as long as adj channel users are 12.5, than there is no distance restrictions. If an adj channel user is 25 or 6.25 (ie nyc) than you physically have to be separated by 64km (40 mi) or produce a tsb88 study that proves less than 5% interference in both directions if closer than 40 miles.

Digital modulation will absolutely push the tsb study over analog by as much as 15%, depending on terrain and height.

You would do better putting in for another PW 450 or 460, or even an IG channel for what you are looking to do. It will be quicker and easier.

[MassFD]

Adjacents on both sides at the same site?

How well do the three channels play together right now?

They get along OK as 12.5 analog, I do have several other sites at about 2.5 miles out and could split the freqs between them if I had to. They are all low power (10 watt out) on 3db gain antennas. I guess they are not realy adjacents since narrow banding as they are 25khz removed (600.625and650)

[MassFD]

Rob, kinda late for breakfast.

The freq in question has (at lst look) no co channel under 40 miles so it just may fly. Have to do some research to make sure nothing new has poped up. We had all 3 as clear at 1 time but then assigned Westchester without any input from us, when we went to do a mod we then had to get a concurance from Westchester. How they got the freq without a concurance from us I do not know.

[FMROB]

Westchester is a puzzling agency when it comes to licenses, lol. If you need anything give me a shout. Thx, rob

[Bill_G]

Adjacents on both sides at the same site?

How well do the three channels play together right now?

They get along OK as 12.5 analog, I do have several other sites at about 2.5 miles out and could split the freqs between them if I had to. They are all low power (10 watt out) on 3db gain antennas. I guess they are not realy adjacents since narrow banding as they are 25khz removed (600.625and650)

If they worked well together in analog, then they should be okay in Trbo. Just use the same kind of duplexers.

[escomm]

The Suspension Notice stated that the suspension included “applications that seek to modify
existing licenses by changing technical parameters in a manner that expands the station’s
spectral or geographic footprint.”8 We clarify that applications that seek to add or change an
emission type (the last three characters of the emission designator) are suspended only if the
licensee also proposes to increase the authorized bandwidth. Emission types may be added or
changed so long as the emission remains within the existing authorized bandwidth, even if the
new emission type nominally expands the station’s spectral footprint.9

Are you suggesting that 7K emissions designators occupy more bandwidth than 11K designators?

I stand by my original assertion.

[MassFD]

I love a good debate, keep it going guys. I want as much info as I can get before I attempt this.

Bill_G, the current 3 freqs are on 4 cavity cellwave pass/reject duplexers that I plan to reuse as they work fine.

Rob, thanks for the offer.We are going to leave the freq with Westchester on analog just to avoid the hassel. At this time they want to do 1 freq for district ops so they can have a little privacy.

[FMROB]

The Suspension Notice stated that the suspension included “applications that seek to modify
existing licenses by changing technical parameters in a manner that expands the station’s
spectral or geographic footprint.”8 We clarify that applications that seek to add or change an
emission type (the last three characters of the emission designator) are suspended only if the
licensee also proposes to increase the authorized bandwidth. Emission types may be added or
changed so long as the emission remains within the existing authorized bandwidth, even if the
new emission type nominally expands the station’s spectral footprint.9

Are you suggesting that 7K emissions designators occupy more bandwidth than 11K designators?

I stand by my original assertion.

Jeff,

No, I am certainly not saying that. I should have expanded my explanation a bit, as the OP and I are affiliated with the same agency, so some of the goings on were dealing with known issues.

To further expand what I was referencing, the original T Band freeze would not allow you to change your emissions mask. That was latter clarified in the info that we posted and reference, to a degree. In our market, T Band is beyond saturated, especially right next door to the spectrum hogs (NYC). With that being said, the coordinators specifically dealing with the NY Metro market have clamped down on Trbo systems. They are very hesitant to approve systems that would normally pass in analog, and rightfully so. Even though the emissions mask is a lower bandwidth than analog voice, you take the hit on the TSB study, which was really what I was trying to point out to the OP, knowing the cadre of channels he has available. We have had a few local governments in t band attempt to change from analog to trbo and were told by the coordinators not without a waiver.

Rob

[MassFD]

Just to let all who replyed know, we did apply for a mod to add 7K emmissions for MotoTrbo on a uhf T band freq and it was approved. The closesest adjcent user (12.5 removed) is at 33.74 miles, the 25K removed freqs (under 40 miles) are licensed to us so no objection there.

Thanks to all who replied, some great discussion here.