FCC Correspondance Regarding Vehicle Level Test Method

FCC ID: CB2ACTLHL3

Cover Letter(s)

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FCCID_350086

Summary of vehicle level testing incorporated into a Class II permissive change: The Johnson Controls Universal Garage Door Opener (UGDO hereafter) is designed for permanent installation into an automobile. Once installed it is designed to take the place of an original transmitter. The fixed position and mounting of the UGDO provides about 10dB attenuation. Per the attached correspondence, Prince Corporation (now Johnson Controls) sought to remedy this handicap by way of a vehicle level certification. Under this agreement, Johnson Controls is allowed to adjust output power of the transmitter to account for the attenuation introduced by the vehicle. The vehicle is then tested as a DUT on an FCC approved site to ensure that the overall emission is below the prescribed limit. Additionally, spurious emissions must remain below the limit when the UGDO is tested normally per ANSI C63.4-1992. In short, the fundamental is allowed to exceed the limit as long as it is below the limit once installed into the intended vehicle. In contrast, the harmonics must remain below the limit as normally tested. This certification is intended to apply to a specific vehicle model.

urlcATioy, FEDERAL COMMUNICATIONS COMMISSION &1 C ‘?i: a < Equipment Authorization Division,Application Processing Branch 7435 Oakdand Mills Road, Columbia, MD 21048 $ Telephone: (301) 725—1585,ext 230 _Fax: (301) 344—2050 & c usa +C e—mail:GCZUMAK@FCc.cov DATE:111497 FROM: Gregory M. Czumak REFERENCE: your letter dated September 15, 1997 NO. OF PAGES: one TO: Terry Mahn OBEANE:HON: Fish & Richarg!_son <—w«_ enz nmmmeemmammermmmmmrmmme Dear Terty: This is in response to your letter dated September 15, 1997. Please excuse the delay. The test and reporting procedure for the Prince Universal Garage Door Opener (UGDO), as outlined in your letter to me dated August 19, 1997, and modified in your jetter dated September 15, 1997, is acceptable. Pleass include copies of those letters, as well as a copy of this confirmation, in any epplications which Prince files in which they make use of the referenced procedure. Please note that this procedure is applicable only to Prince Corporation and their UGDO product. Any changes to the referenced procedure must approved by the FCC prior to implementation. If you have addifional questions on this subject, please do not hesitate to confad me by fax, phone or e—mail. RECEIVED Noy 14 n FISH & Rickanp wasHineton,o.c."

Fisn &« RICHARDsON P.C. 6o1 Thirteenth Street x.w. Washington, DC 20005 Frederick P. Fish Telephone 1855—1930 202 783—5070 W.K. Richardson Facsimil 1859—1951 202 783—2331 September 15, 1997 Mr. Greg Czumak Electronics Engineer FCC Laboratories 7435 Oakland Mills Rd. Columbia, MD 21046 Re: Our File 05238/002001 BOSTON HOUSTON Dear Greg: NEW YORK SOUTHERN CALIFORNIA Per our recent discussion, this will confirm Prince‘s understanding of, and agreement with, the minor changes you requested to our letter of August 19, 1997. These were as SILICON VALLEY follows: TWIN CITIES WASHINGTON, DC In paragraph 4a, the phrase "Class II changes" shall be replaced with "in—vehicle output level adjustments." Regarding paragraph 6, you and I agreed that Prince can avail itself of the following measurement options: (1) Prince will not be required to measure harmonic emissions. "on—site" provided a Class II filing is submitted to the Commission for each vehicle model (but not classes within the same model line) tested; or (2) Prince can measure the harmonics "on—site" and make a Class I/II determination (and filing, as required) for each model tested. _ Finally, we would like to note, for the record, that all references to the University of Michigan test site are meant to be applicable to any FCC—listed test site. This will give Prince the flexibility to use other FCC—listed sites (including its own site) to perform the "baseline" measurements on the UGDO. I trust this completes this matter and that you will provide a written confirmation of the same. Thank you again for your patience and cooperation in this matter. Very truly yours, Terry (¥ Mahn Iseg co: Paul Duckworth, Prince Corporation Ed Gibbons, FCC—Ret. 78394.W11

Fisxmx & RIcHARDsoN P.C. 6o1 Thirteenth Street n.w. Washington, c 20005 Frederick P. Fish Telephone 1855—1930 202 783—5070 W.K. Richardson Facsimile 1859—1951 202 783—2331 August 19, 1997 Mr. Greg Czumak Electronics Engineer FCC Laboratories 7435 Oakland Mills Rd. Columbia, MD 21046 BOSTON Re: Our File 05238/0020(\ HOUSTON NEW YORK Dear Greg: OUTHERN CALIFORNIA SILICON VALLEY This is to follow up our meetingthe FCC Labs on June 3, 1997, attended by you, TWIN CITIES Ed Gibbons, Paul Duckworth of Prince Corporation and nfex:Thepurpose of the meeting was to develop an updated test procedure for the ceunliversal garage door opener (UGDO) to accommodate the various types of autorfibbiles in which the device is now being factory—installed. In previous correspondence, Ed set forth the basic test procedures for measuring the UGDO on an open area test site. Ed advised Prince that, historically, "in vehicle" testing for garage door openers had never been authorized by the Commission due to the wide variations in vehicle shielding and the mobility of battery—powered door openers. For this reason, Prince‘s UGDO was required to follow the traditional door opener test procedures notwithstanding its "fixed" location inside of vehicles. In addition, the UGDO was required to be tested with a representative wiring harness to simulate possible antenna effects. As explained during our meeting, the UGDO, when factory—installed, is typically | located in overhead consoles or vanity—pack visors which are often locatedhigh up in the vehicle‘s metal structure, where RF shielding is the most severe. Prince estimates that its UGDO incurs a 5 to 10 dB signal loss compared to that measured on a test site. To compensate for this attenuation, and thereby restore lost operating range, vehicle manufactures have had to devise a number of passive enhancements to direct the UGDO‘s signal away from the vehicle‘s shielding. Such practice, however, is both time consuming and expensive for Prince as well as for the vehicle manufactures; moreover, what it accomplishes —— restored signal strength —— could just as easily be accomplished by making a slight adjustment in the UGDO‘s test procedures.

Fisnx & RIcHaAaRDsON P.C. Mr. Greg Czumak August 19, 1997 Page 2 As Paul also mentioned during our meeting, the UGDO is currently featured in over 60 automobile models as original equipment or in upgrade packages. Leading garage door opener manufacturers have begun to standardize on the UGDO technol— ogy and it is now being integrated with other wireless home security offerings. For the technology to continue to be cost effective for the driving public, however, Prince must find a way to reduce the considerable expense that goes into the tailoring of custom passive designs for every vehicle installation. You and Ed agreed that Prince‘s goal could be achieved without compromising the integrity of the Commission‘s measurement process or increasing the risk of spectrum interference. The following procedures, therefore, were agreed to by the Commission for all future certifications and permissive changes for Prince‘s UGDO products: 1. All testing is to be conducted at FCC—listed sites. 2. Prince will obtain a single certification for its UGDO design; all models within each vehicle manufacturer‘s product line will be Class I or Class II permissive changes to Prince‘s certified UGDO as described in the procedures that follow. 3. Prince currently has two board—level variations of the UGDO for — which the RF sections are essentially identical; initial testing will con— firm which of the two boards exhibits the "worst case"; the other board will then be considered to be a Class I permissive change: 4. .a. Initial testing on the UGDO —at the University of Michi— gan test labs will be conducted at three frequencies (low, middle and high) over the device‘s operating range and on three duty cycles (low, middle and high); to accommodate future Class II changes, the fundamen— tal emissions at each tested frequency will be permitted to exceed the limits of Rule 15.231 by an amount, to be determined by Prince but estimated to be 10 dB, provided all harmonic and restricted band emissions are within FCC limits as set forth in Rule 15.231 at the se— lected fundamental levels; this will establish the certifi— cation " baseline" for the UGDO such that only funda—

Fisu &« RICHARDSsON P.C. Mr. Greg Czumak August 19, 1997 Page 3 mental emissions testing will need to be performed in vehicles tested "on site" at an FCC—listed facility. b. All modifications to Prince‘s board design will be tested at the Michigan site under the procedures set forth above; the fundamental emission level will be adjusted so as NOT to exceed the level measured in the original "baseline" report, and Prince will ensure that all harmonics are within the Rule 15.231 limits. If all harmonics are at or below the original levels the modi— fication will be considered a Class I change and noth— ing further will need to be done. However, if any har— monics are above the original "baseline" (but still with— in the limits), Prince will conduct an "on site" test in one vehicle and file a Class II change report to the original certification (see 6 below) with the FCC —— the filed test report consisting of the new "baseline" test plus the "on site" test. Testing in all vehicle mod— els will not be required for modifications tested in this manner. For each automobile manufacturer, every model in the manufacturer‘s product line will be tested "on site" with the UGDO installed and operating at three frequencies (lIow, middle and high). As used here, "on site" refers to the testing of an actual vehicle, with UGDO in— stalled, on a turntable at a listed site; only fundamental emissions will need to be measured "on—site" since compliance of the harmonics and restricted bands has already been confirmed by open field measure— ments of the UGDO at the Michigan labs; in order to maximize the field strength levels outside the vehicle Prince will be allowed to adjust the fundamental lev?‘lu:g_‘gny iven duty cycle (via digital coding of the UGDO) within Thd'\c?‘fi% cycle range determined in Step 4 above provided the measured fundamental level does not exceed the Rule 15.231 limits. When adjusting the UGDO fundamental level, the maximum level established in Step 4 will not be exceeded in any case.

Fisnx & RIcHKaRDSON P.C. Mr. Greg Czumak August 19, 1997 Page 4 6. Prince will submit to the FCC labs, the "baseline" test report from the University of Michigan labs along with the "on site" test report from a selected vehicle model, the combination of which will form the certification application to the FCC for the UGDO; all other vehicle models from each manufacturer (but not different versions or classes within the same model line) will be tested "on site" in the same man— ner with the results evaluated by Prince under the permissive change rules as either Class I or Class II changes, with any Class II permis— sive changes filed with the FCC as required under the Part 2 Rules. I trust this accurately sets forth the test procedures upon which we agreed. If you have any comments or corrections to the foregoing, please contact me immediately. I look forward to your written concutrrence in this matter. — Very truly yours, 7 Terry G. Iseg ©o: Ed Gibbons, FCC—Ret. Paul Duckworth, Prince Corporation 76230.W11


Document Created: 2003-08-22 09:11:47
Document Modified: 2003-08-22 09:11:47
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