The truth is we need qualified RF engineers to speak up if they are here. It is my limited RF engineering knowledge which has always led me to believe that F/D Ratio (Focal Length to Diameter Ratio) which determines the beamwidth of the focused RF beam including the spread of the spurious side lobes in microwave parabolic dish antenna systems. If that is the case then the F/D ratio (not the diameter) should be the root of the discussion. The truth is though that I am NOT an RF engineer and therefore not truly qualified to make any genuine comment on the issue until I hear more from engineers who know. If this group wants to devote resources to this issue I am sure we could setup a committee to work on 11 GHz dish size issues. I am just seeing this as a minor issue. I am sorry to those out there who think this makes me short-sighted.
Scriv

Jack Unger wrote:

Brad,

I see how my original comment could have been misinterpreted. There was an element of "I don't have time for this". Now that I've taken the time (that I didn't have) and (hopefully) asked the right questions, I think it's time for others to follow up if they feel it's an important issue.

Personally, I'm not worried at this point about allowing smaller 11 GHz antennas. I don't think it's going to cause us any problems with frequency availability. I think 11 GHz frequencies will be available when they are needed. FiberTower's investors include American Tower, Crown Castle and SpectraSite. I can't believe that those companies would want to do anything to "screw up" either the availability of frequencies or the sale of "vertical real estate" on their tower properties.

Have a good day,

jack



Brad Belton wrote:

Hello Jack,

Good to see you're back on track with, IMO, a proper response to the 11GHz
question/concerns.

Your initial comment came off as who cares and we don't have time for this. John simply dittoed your comments, so what was the group left to believe? I apologize if I misunderstood your intent. Your questions/response below illustrate the type of post I would have
expected from you in the first place.

Best,


Brad


-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Jack Unger
Sent: Tuesday, March 27, 2007 1:33 AM
To: WISPA General List
Subject: Re: [WISPA] FCC requests comment on smaller dishes for 11 GHz

Brad,

I think you may be misquoting or misunderstanding me. No good can come from that. Real questions need to be asked and need to be correctly answered before we risk our reputation by filing comments with the FCC that are technically incomplete or technically incorrect.

Here's a repost of my original post.

****************** Begin Original Post *********************************

It would be good to know the minimum required dish size now and the changes that FiberTower is proposing before deciding what to do or say.

I'm not sure this dish-size issue would impact any WISPs so we may want to ask ourselves if there are more important issues that we need to be focusing on, given the limited time and resources that we have.

I think this is an issue that the licensed microwave vendors will probably deal with adequately, without harming our interests. When we decide to purchase a licensed 11 GHz link, we'd be buying it from them anyway.

Finally, WISPA doesn't have an engineering staff that can adequately analyze the technical implications and prepare an informed technical response to submit to the FCC.

******************** End Original Post *********************************


NOWHERE did I say that the licensed frequency bands are not important to WISPS. Licensed backhauls are very important to WISPs. WISPs SHOULD use licensed backhauls wherever interference levels are high, where reliability is crucial, where throughput needs are high, and/or where full duplex links are needed.

NOWHERE did I say that the focus of the group should be limited to unlicensed frequencies only.

TO BE CRYSTAL CLEAR, I will restate each original paragraph and I will list the questions that each paragraph is implicitly asking.

****************************************************************************
***

PARAGRAPH 1 - "It would be good to know the minimum required dish size now and the changes that FiberTower is proposing before deciding what to do or say". In other words, we need to know the minimum dish size now and we need to know what dish sizes FiberTower is proposing before we can begin to understand if there is any affect on us and before we can formulate our position.

QUESTION: SO WHAT ARE THOSE DISH SIZES NOW, BEFORE A RULES CHANGE AND AFTER THE PROPOSED RULES CHANGE?

QUESTION: WHAT'S THE TRUE IMPACT, IF ANY, ON US IF THE FCC ALLOWS SMALLER DISH SIZES TO BE USED?

QUESTION: ONCE WE UNDERSTAND THE TRUE IMPACT, IF ANY, WHAT POSITION SHOULD WE TAKE BEFORE THE FCC?

****************************************************************************
**

PARAGRAPH 2 - "I'm not sure this dish-size issue would impact any WISPs so we may want to ask ourselves if there are more important issues that we need to be focusing on, given the limited time and resources that we have".

QUESTION: DOES A REDUCTION IN DISH SIZE REALLY AFFECT US?

QUESTION: HOW DOES IT REALLY AFFECT US? ARE 11 GHz FREQUENCIES CURRENTLY IN SHORT SUPPLY IN THE AREAS WHERE MOST WISPs OPERATE?

QUESTION: HAS ANY WISP EVER BEEN DENIED A LICENSE FOR AN 11 GHz FREQUENCY? IF SO, WHERE? HOW OFTEN HAS THIS HAPPENED?

QUESTION: ARE THERE MORE IMPORTANT ISSUES BEFORE THE FCC THAT WE NEED TO DEVOTE OUR TIME AND ENERGY TO? WHAT ARE THOSE ISSUES? WHITE SPACE? WISPS AS AN INFORMATION SERVICE? FCC's BROADBAND SERVICES SURVEY? CALEA? OTHERS??

****************************************************************************
*

PARAGRAPH 3 - "I think this is an issue that the licensed microwave vendors will probably deal with adequately, without harming our interests. When we decide to purchase a licensed 11 GHz link, we'd be buying it from them anyway".

QUESTION - IF ALLOWING SMALLER DISH SIZES WAS GOING TO CREATE INTERFERENCE PROBLEMS WOULDN'T THE COMPANIES THAT MAKE 11 GHz EQUIPMENT BE AGAINST THE PROPOSED CHANGES BECAUSE THAT WOULD RESULT IN THEM SELLING FEWER LICENSED 11 GHz LINKS AND HAVING HIGHER CUSTOMER SUPPORT COSTS?

***************************************************************************

PARAGRAPH 4 - "Finally, WISPA doesn't have an engineering staff that can adequately analyze the technical implications and prepare an informed technical response to submit to the FCC".

QUESTION - DO WE HAVE THE ENGINEERING KNOWLEDGE TO REALLY KNOW WHAT THE TRUE EFFECTS OF ALLOWING SMALLER DISH SIZES WILL BE?

QUESTION - A SMALLER ANTENNA WILL HAVE LARGER SIDELOBES. IS THIS REALLY AN ISSUE OR ARE 11 GHz ANTENNAS NORMALLY MOUNTED WITH A FEW FEET OF VERTICAL SEPARATION ANYWAY SO THAT A MARGINAL INCREASE IN SIDELOBES WILL REALLY HAVE NO IMPACT ON ANYONE ELSE ANYWAY?

QUESTION - SHOULD THE FCC GIVE ANY WEIGHT OR CREDIBILITY TO OUR OPINIONS AND OUR GUESSES OR SHOULD THEY ONLY GIVE WEIGHT TO REAL ENGINEERING ANALYSIS?

QUESTION - WHO IN WISPA IS AN ENGINEER AND HAS ACTUALLY DESIGNED, ENGINEERED, AND DEPLOYED A SIGNIFICANT NUMBER OF 11 GHz LINKS? SURELY SOMEONE HAS... WHO IS THAT PERSON? WILL THEY STEP UP AND DO SOME REAL ENGINEERING ANALYSIS FOR US ON THIS ISSUE?

QUESTION: WILL THAT ENGINEERING ANALYSIS SHOW THAT THERE IS ANY REAL IMPACT TO OUR ABILITY TO OBTAIN AND USE LICENSED 11 GHz LINKS IF THE FCC ALLOWS SMALLER ANTENNAS TO BE USED?

QUESTION: WILL ALLOWING SMALLER ANTENNAS ACTUALLY BENEFIT US BECAUSE OUR COSTS TO DEPLOY LICENSED LINKS WILL BE LOWER? (SMALLER ANTENNAS COST LESS TO BUY AND SMALLER ANTENNAS COST LESS TO MOUNT ON TOWERS).

***************************************************************************

That's it, Brad. Your help would be most appreciated to get real answers. If I'm "off the mark" as you believed, that's OK with me as long as it leads to an understanding of what the real issues are and builds our credibility with the FCC, the manufacturers, and the public at large. Real understanding benefits everybody.

Best Regards,
                jack



Brad Belton wrote:


Agreed. Just getting caught up on some of my email readings and strongly believe Jack and John are off the mark here. 6GHz, 11GHz, 18GHz, 23GHz, 24GHz, 60GHz and 80-90GHz should all be


important

to us as a group.  Any frequency that can be used by fixed wireless
operators should be important to the group.

For Jack and John to assume the focus as a group should be limited to UL
frequencies is short sighted to say the least.  Many operations, ours
included, are already utilizing licensed spectrum were we can.

Best,


Brad




-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Tom DeReggi
Sent: Monday, March 26, 2007 2:10 PM
To: WISPA General List
Subject: Re: [WISPA] FCC requests comment on smaller dishes for 11 GHz

Anything related to 11Ghz, should be WISPs concern. It is my belief that all serious unlicensed ISPs will at some point start to migrate to


Licensed

spectrums for backhauls. 11Ghz is one of the few upgrade options available



for WISP's that designed their existing backhaul to 5.8Ghz functionality. (meaning needing 4ft dish 11Ghz to reach equivellent distances of 5.8Ghz


2ft

dish links, in practicality). There really aren't very many Long range backhaul spectrum range options out there. Relaxing the rules could


result

in the inabilty for many WISPs to obtain 11Ghz licenses, because of unavailable spectrum, when they are ready to need it. A 2ft dish


beamwidth

(9-10 degrees) will cover the width of most of a small city at 10 miles. (Sorry I didn't do the Angle math yet). Compared to that of 4 ft dish beamwidths. As much as I'd like a 2 ft Dish, how would that effect my future abilty to get a license? Thats an important question. Fibertower wants 2ft dishes today because they are ready to buy up the licenses


today.

Are the rest of the WISPs ready to buy the licenses today? How much


license

space is available still? I think some propogation data and current saturation data (number of links / potential for more links) would need to



be disclosed first to develop a relevant opinion. And how would the rules



effect cost? Currently 11Ghz is significantly more expensive to obtain because of dish size. If smaller more advanced dishes were allowed, a 2ft dish that had the characteristics of 3-4ft dishes, would those dishes be more expensive because of their unique better characterisitcs? The truth



is, every provider would chose 11Ghz over 18Ghz, if they could get away


with

a smaller dish. It would likely lead to less use of 18Ghz and 23 Ghz. Is 18Ghz getting saturated? If so it would be relevent to allow 11Ghz to take



over the load. But I'd argue that 18Ghz should be near at capacity before



11Ghz be allowed to be more leanent in antenna size.

The bigger fight for smaller antennas is to allow 6Ghz to be allowed to


use

4 ft dishes. 6ft dish requirement is insane. If 6Ghz was allowed to use


4ft

dished, it would then give another option for long range, (within a realistic antenna size for roof tops), then justifying the allowance for 11Ghz to have smaller antennas. The question is, why isn't Fibertower


just

using 18Ghz in their applications? Can they prove that 18Ghz is to


limiting

or unavailable for them?

Tom DeReggi
RapidDSL & Wireless, Inc
IntAirNet- Fixed Wireless Broadband





John Scrivner wrote:

Thank you Jack. You said it better than I could have.
:-)
Scriv


Jack Unger wrote:



Dylan,

It would be good to know the minimum required dish size now and the
changes that FiberTower is proposing before deciding what to do or say.

I'm not sure this dish-size issue would impact any WISPs so we may
want to ask ourselves if there are more important issues that we need to be focusing on, given the limited time and resources that we have.

I think this is an issue that the licensed microwave vendors will
probably deal with adequately, without harming our interests. When we decide to purchase a licensed 11 GHz link, we'd be buying it from them anyway.

Finally, WISPA dosn't have an engineering staff that can adequately
analyze the technical implications and prepare an informed technical responese to submit to the FCC.

jack


Dylan Oliver wrote:



I recall some past discussion bemoaning the large dish sizes required
for
licensed links .. I just found this in the latest "Rural Spectrum Scanner"


from Bennett Law (http://www.bennetlaw.com/rss.php?vol=13&issue=12).


Should
WISPA endorse this? I'm not familiar with the details of 11 GHz regulation.

*FCC Seeks Comment on the Use of Smaller Antennas in the 11 GHz Band*

The FCC has released a *Public Notice* announcing that it has adopted
a *Notice
of Proposed Rulemaking* seeking comment on whether to permit the
installation of smaller antennas by Fixed Service (FS) operators in the 10.7-11.7 GHz band. The FCC initiated the rulemaking pursuant to a Petition for Rulemaking filed by FiberTower, Inc., a wireless backhaul provider, proposing to change the technical parameters that would permit the use of smaller FS antennas with reduced mainbeam gain, increased beamwidth, and modified sidelobe suppression in the 11 GHz band. The FCC seeks comment on whether FiberTower, Inc.'s proposals would serve the public interest by facilitating the efficient use of the 11 GHz band while protecting other users in the band from interference due to the use of smaller antennas. The
pleading cycle has not yet been established.

Best,





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