FCC Logo - Return to the FCC Home Page
Office of Engineering and Technology

  

Print This Window
There have been 7 comment(s) made on this document:
  • Thomas Whissel commented on 2010-09-28 09:24:37.62:
    I would like to see an option for devices used outdoors that can be installed by the user when operating in the 5470-5725 MHz Band. These devices could be operated outdoors provided it does not operate on channels centered from 5570-5680 MHz. This would eliminate any potential interference regardless of installation location. Thanks, Tom

  • David Case commented on 2010-09-28 09:22:16.126:
    Comments filed on behalf of members of Industry workgroup Re: Comments on KDB 443999 “Interim Certification Procedure for UNII Devices Operating in the 5470-5725 MHz Band with Radar Detection and DFS Capabilities” Via E-Mail Dear Dr. Doshi: On September 16, 2010, the OET Lab published a draft Knowledge Database (KDB) guidance which will, once implemented, permit the FCC to re-start certifications for outdoor UNII devices in the 5470-5725 MHz band, subject to the conditions detailed in the KDB. With certifications for outdoor equipment on hold for this band for over a year, industry welcomes the opportunity to re-open most of the band. The signatories listed below look forward to offering the latest in wireless broadband technology and capabilities, while recognizing that avoiding harmful interference to Terminal Doppler Weather Radar systems used near airports is an issue requiring the collective action of manufacturers, installers and the user communities. Industry is pleased that the FCC, along with NTIA and FAA, have reached a point where they recognize that there are tools available to address the issues that have been identified with respect to TDWRs. The signatories below are pleased with the overall draft, and believe that, once implemented; it should contribute to elimination of interference cases going forward. In fact, the sooner manufacturers can bring revised product to market, the better. While we endorse the draft KDB overall, we believe three modifications are warranted. (1) The draft KDB states, in the second to last full paragraph, that the grantee “…must demonstrate through test reports that the transmission is disabled in the 5600-5650 MHz band.” The signatories believe that a signed attestation statement that production software will lock out the TDWR frequencies should suffice as demonstration of compliance with the notching requirement. This would avoid having to create new test software for the FCC lab. The current test software in use by industry (as required by the FCC lab) is used to test products globally and the requirement to add the TDWR band notch into test software and demonstrate testing compliance would slow the approval process. Moreover, testing for the absence of an ability to utilize an identified band of frequencies is essentially an exercise in proving a negative, and does not address the need to create the notch in the unit’s production software. (2) Once the issue of Bin 1 radar wave forms is addressed and the products are modified to detect the new Bin 1 radar forms, manufacturers should be able to utilize a Class II FCC approval process to update products, and to allow products in the field to be updated, even if the product is not approved as a software defined radio. Industry recommends this guidance to be similar to that provided in KDB 926956 question 2. Modifying the KDB to specify a path forward, once a permanent solution is identified, is important so that manufacturers can begin communicating about these future changes with customers and others now. (3) In the discussion in the final paragraph on manufacturers’ obligation to ensure equipment complies with FCC rules and the steps to be taken to ensure that their devices are unlikely to be a source of harmful interference, a clarification of some of those steps would be useful to manufacturers. The signatories propose to clarify the following text as shown and add a footnote to “…and must take steps to ensure their devices do not are unlikely to cause harmful interference [insert footnote],…”. The footnote would read “Such steps include clear instructions to operators and installers of devices as to the need to comply with rules for use of the band, guidance on registration of devices and any other processes which are designed to avoid interference. Methods include, but are not limited to, instructions in manuals, notification on product web pages and / or service bulletins issued for product in the field.” Manufacturers do have significant influence on methods to reduce interference but do not have complete control of the use of such devices as is recognized in other sections of this paragraph. None of these modifications will adversely affect the ability of the FCC to guard against harmful interference in the band. In fact, the signatories believe the proposed changes will help speed the process of migrating to the interim procedures, and eventually, moving to the permanent test procedures that are needed to protect TDWRs, while providing clear guidance to manufacturers. The signatories therefore request that the KDB, modified as described herein, be implemented as quickly as possible. Respectfully submitted, Clark Vitek Ivaylo Tankov Aruba Networks Michael Green Tevfik Yucek Atheros David Case Mary Brown Cisco David Boldy Broadcom Robert Paxman Eldad Perahia Vijay Auluck Intel Steve Payne Rob Kubik Clem Fisher Motorola Inc. Cor van de Water Proxim Corp. Greg Bedian Ubiquiti Networks

  • Damian Wallace commented on 2010-09-22 19:54:02.35:
    In Section "Devices will not permit operation on channels which overlap the 5600 – 5650 MHz band." can this be changed to "Transmit" instead "operate". This will allow us to add functionality to the device to scan in this band, and report if radar was seen. In cases where the unit is more than 35 KM away but still has LOS, this will allow the user to check if they might be causing issues for Radar and move 30 MHz away.

  • Damian Wallace commented on 2010-09-22 17:42:57.973:
    For the section "Devices will not permit operation on channels which overlap the 5600 – 5650 MHz band", could this be not permit "transmission" as opposed to "operation". This would allow the device to report to the user that Radar was seen in the 5600-5650 band during an initial scan. This would help in cases where the device is more than 35KM from the TDWR but is still potentially have an impact, and the user to take action such as moving 30 MHz away.

  • Mike Heckrotte commented on 2010-09-21 14:32:09.186:
    "...and must demonstrate through test reports that the transmission is disabled in the 5600 – 5650 MHz band."
     
    In general it is conceptually difficult to develop a test to prove a negative, please advise an/the applicable test procedure to demonstrate that the above requirement has been met.

  • Willem Jan Jong commented on 2010-09-20 04:10:42.526:
    When this interim procedure is published, will UNII devices with DFS capabilities remain on the TCB exclusion list? A note or phrase stating that TCB's can or can not review this kind of devices might be usefull information.

  • Mark Briggs commented on 2010-09-17 12:07:31.24:
    Rashmi - congratulations on getting this far!! Could you please confirm (in the final KDB) if there are additional/modified radar waveforms to be detected or if the current 6 radar types will remain unchanged? Thanks Mark

Note: It is important to understand that the staff guidance provided in the KDB is intended to assist the public in following Commission requirements and does not constitute rules. Accordingly, the guidance is not binding on the Commission and will not prevent the Commission from making a different decision in any matter that comes to its attention for resolution.