§  15.711   Interference avoidance methods.

   Except as provided in § 15.717 of this part, channel availability for a
   white space device is determined based on the geo-location and database
   access method described in paragraphs (a) through (e) of this section.

   (a) Geolocation required. White space devices shall rely on a
   geolocation capability and database access mechanism to protect the
   following authorized service in accordance with the interference
   protection requirements of § 15.712: Digital television stations,
   digital and analog Class A, low power, translator and booster stations;
   translator receive operations; fixed broadcast auxiliary service links;
   private land mobile service/commercial radio service (PLMRS/CMRS)
   operations; offshore radiotelephone service; low power auxiliary
   services authorized pursuant to § § 74.801 through 74.882 of this
   chapter, including licensed wireless microphones; MVPD receive sites;
   wireless medical telemetry service (WMTS); radio astronomy service
   (RAS); and 600 MHz service band licensees where they have commenced
   operations, as defined in § 27.4 of this chapter. In addition,
   protection shall be provided in border areas near Canada and Mexico in
   accordance with § 15.712(g).

   (b) Geo-location requirement--(1) Accuracy. Fixed white space devices
   that incorporate a geo-location capability and Mode II devices shall
   determine their location and their geo-location uncertainty (in
   meters), with a confidence level of 95%.

   (2) Reference datum. All geographic coordinates shall be referenced to
   the North American Datum of 1983 (NAD 83).

   (c) Requirements for fixed white space devices. (1) The geographic
   coordinates of a fixed white space device shall be determined at the
   time of installation and first activation from a power off condition by
   an incorporated geo-location capability. The antenna height above
   ground shall be determined by the installer or operator of the device,
   or by an automatic means. This information shall be stored internally
   in the white space device and transmitted automatically by the device
   to the white space database. The operator of a fixed white space device
   shall be responsible for assuring the accuracy of the information
   registered in the white space database. If a fixed white space device
   is moved to another location or if its stored coordinates become
   altered, the operator shall reestablish the device's:

   (i) Geographic location through the incorporated geo-location
   capability and the antenna height above ground level and store this
   information in the white space device; and

   (ii) Registration with the database based on the device's new
   coordinates and antenna height above ground level.

   (iii) A fixed white space device may obtain its geographic coordinates
   through an external geo-location source when it is used at a location
   where its internal geo-location capability does not function. An
   external geo-location source may be connected to a fixed device through
   either a wired or a wireless connection, and a single geo-location
   source may provide location information to multiple fixed devices. An
   external geo-location source must be connected to a fixed device using
   a secure connection that ensures that only an external geo-location
   source that has been approved with a particular fixed device can
   provide geographic coordinates to that device. The geographic
   coordinates must be provided automatically by the external geo-location
   source to the fixed device; users may not manually enter them.
   Alternatively, an extender cable may be used to connect a remote
   receive antenna to a geo-location receiver within a fixed device.

   (iv) The applicant for certification of a fixed device must demonstrate
   the accuracy of the geo-location method used and the location
   uncertainty as defined in paragraph (b) of this section. For fixed
   devices that are not using an internal geo-location capability, this
   uncertainty must account for the accuracy of the geo-location source
   and the separation distance between such source and the white space
   device.

   (2)(i) Each fixed white space device must access a white space database
   over the Internet to determine the available channels and the
   corresponding maximum permitted power for each available channel that
   is available at its geographic coordinates, taking into consideration
   the fixed device's antenna height above ground level and geo-location
   uncertainty, prior to its initial service transmission at a given
   location.

   (ii) Operation is permitted only on channels and at power levels that
   are indicated in the database as being available for each white space
   device. Operation on a channel must cease immediately or power must be
   reduced to a permissible level if the database indicates that the
   channel is no longer available at the current operating level.

   (iii) Each fixed white space device shall access the database at least
   once a day to verify that the operating channels continue to remain
   available. Each fixed white space device must adjust its use of
   channels in accordance with channel availability schedule information
   provided by its database for the 48-hour period beginning at the time
   the device last accessed the database for a list of available channels.
   The fixed device's registration information shall be updated if the
   geographic coordinates reported to the database differ by more than ±50
   meters from the previously registered coordinates.

   (iv) Fixed devices without a direct connection to the Internet: A fixed
   white space device may not operate on channels provided by a white
   space database for another fixed device. A fixed white space device
   that has not yet been initialized and registered with a white space
   database consistent with § 15.713 of this part, but can receive the
   transmissions of another fixed white space device, may transmit to that
   other fixed white space device on either a channel that the other white
   space device has transmitted on or on a channel which the other white
   space device indicates is available for use to access the database to
   register its location and receive a list of channels that are available
   for it to use. Subsequently, the newly registered fixed white space
   device must only use the channels that the database indicates are
   available for it to use.

   (d) Requirements for Mode II personal/portable white space devices. (1)
   The geographic coordinates of a Mode II personal/portable white space
   device shall be determined by an incorporated geo-location capability
   prior to its initial service transmission at a given location and each
   time the device is activated from a power-off condition to determine
   the available channels and the corresponding maximum permitted power
   for each available channel at its geographic coordinates, taking into
   consideration the device's geo-location uncertainty. The location must
   be checked at least once every 60 seconds while in operation, except
   while in sleep mode, i.e., in a mode in which the device is inactive
   but is not powered-down.

   (2) Each Mode II personal/portable white space device must access a
   white space database over the Internet to obtain a list of available
   channels for its location. The device must access the database for an
   updated available channel list if its location changes by more than 100
   meters from the location at which it last established its available
   channel list.

   (3) Operation is permitted only on channels and at power levels that
   are indicated in the database as being available for the Mode II
   personal/portable white space device. Operation on a channel must cease
   immediately or power must be reduced to a permissible level if the
   database indicates that the channel is no longer available at the
   current operating level.

   (4) A Mode II personal/portable white space device that has been in a
   powered state shall re-check its location and access the database daily
   to verify that the operating channel(s) and corresponding power levels
   continue to be available. Mode II personal/portable devices must adjust
   their use of channels and power levels in accordance with channel
   availability schedule information provided by their database for the
   48-hour period beginning at the time of the device last accessed the
   database for a list of available channels.

   (5) A Mode II personal/portable device may load channel availability
   information for multiple locations, (i.e., in the vicinity of its
   current location) and use that information to define a geographic area
   within which it can operate on the same available channels at all
   locations. For example a Mode II personal/portable white space device
   could calculate a bounded area in which a channel or channels are
   available at all locations within the area and operate on a mobile
   basis within that area. A Mode II white space device using such channel
   availability information for multiple locations must contact the
   database again if/when it moves beyond the boundary of the area where
   the channel availability data is valid.

   (e) Requirements for Mode I personal/portable white space devices. (1)
   A Mode I personal/portable white space device may only transmit upon
   receiving a list of available channels from a fixed or Mode II white
   space device. A fixed or Mode II white space device may provide a Mode
   I device with a list of available channels only after it contacts its
   database, provides the database the FCC Identifier (FCC ID) of the Mode
   I device requesting available channels, and receives verification that
   the FCC ID is valid for operation.

   (2) A Mode II device must provide a list of channels to the Mode I
   device that is the same as the list of channels available to the Mode
   II device.

   (3) A fixed device may provide a list of available channels to a Mode I
   device only if the fixed device HAAT as verified by the white space
   database does not exceed 106 meters. The fixed device must provide a
   list of available channels to the Mode I device that is the same as the
   list of channels available to the fixed device, except that a Mode I
   device may operate only on those channels that are permissible for its
   use under § 15.707 of this part. A fixed device may also obtain from a
   white space database and provide to a Mode I personal/portable white
   space device, a separate list of available channels that includes
   adjacent channels available to a Mode I personal/portable white space
   device, but not a fixed white space device.

   (4) To initiate contact with a fixed or Mode II device, a Mode I device
   may transmit on an available channel used by the fixed or Mode II white
   space device or on a channel the fixed or Mode II white space device
   indicates is available for use by a Mode I device. At least once every
   60 seconds, except when in sleep mode (i.e., a mode in which the device
   is inactive but is not powered-down), a Mode I device must either
   receive a contact verification signal from the Mode II or fixed white
   space device that provided its current list of available channels or
   contact a Mode II or fixed white space device to re-verify/re-establish
   channel availability. A Mode I device must cease operation immediately
   if it does not receive a contact verification signal or is not able to
   re-establish a list of available channels through contact with a fixed
   or Mode II device on this schedule. If a fixed or Mode II white space
   device loses power and obtains a new channel list, it must signal all
   Mode I devices it is serving to acquire and use a new channel list.

   (f) Display of available channels. A white space device must
   incorporate the capability to display a list of identified available
   channels and its operating channels.

   (g) Identifying information. Fixed white space devices shall transmit
   identifying information. The identification signal must conform to a
   standard established by a recognized industry standards setting
   organization. The identification signal shall carry sufficient
   information to identify the device and its geographic coordinates.

   (h) Continuing operation. If a fixed or Mode II personal/portable white
   space device fails to successfully contact the white space database
   during any given day, it may continue to operate until 11:59 p.m. of
   the following day at which time it must cease operations until it
   re-establishes contact with the white space database and re-verifies
   its list of available channels.

   (i) Push notifications. White space device manufacturers and database
   administrators must implement the push notification requirements of
   paragraphs (i)(1) and (2) of this section, and may also implement a
   system that pushes additional updated channel availability information
   from the database to white space devices.

   (1) In response to a request for immediate access to a channel by a
   licensed wireless microphone user, white space database administrators
   are required to share the licensed microphone channel registration
   information to all other white space database administrators within 10
   minutes of receiving each wireless microphone registration.

   (2) White space database administrators shall push updated available
   channel lists to fixed and Mode II personal/portable white space
   devices within 20 minutes of receiving the notification required by
   paragraph (i)(1) of this section. The information need only be pushed
   to white space devices that are located within the separation
   distances, specified in § 15.712(f) of this part, for each licensed
   wireless microphone registration received.

   (3) White space database administrators must update their systems to
   comply with these requirements no later than December 23, 2016.

   (j) Security. (1) White space devices shall incorporate adequate
   security measures to ensure that they are capable of communicating for
   purposes of obtaining lists of available channels only with databases
   operated by administrators authorized by the Commission, and to ensure
   that communications between white space devices and databases are
   secure to prevent corruption or unauthorized interception of data. This
   requirement includes implementing security for communications between
   Mode I personal portable devices and fixed or Mode II devices for
   purposes of providing lists of available channels. This requirement
   applies to communications of channel availability and other spectrum
   access information between the databases and fixed and Mode II devices
   (it is not necessary for white space devices to apply security coding
   to channel availability and channel access information where they are
   not the originating or terminating device and that they simply pass
   through).

   (2) Communications between a Mode I device and a fixed or Mode II
   device for purposes of obtaining a list of available channels shall
   employ secure methods that ensure against corruption or unauthorized
   modification of the data. When a Mode I device makes a request to a
   fixed or Mode II device for a list of available channels, the receiving
   device shall check with the white space database that the Mode I device
   has a valid FCC Identifier before providing a list of available
   channels. Contact verification signals transmitted for Mode I devices
   are to be encoded with encryption to secure the identity of the
   transmitting device. Mode I devices using contact verification signals
   shall accept as valid for authorization only the signals of the device
   from which they obtained their list of available channels.

   (3) A white space database shall be protected from unauthorized data
   input or alteration of stored data. To provide this protection, the
   white space database administrator shall establish communications
   authentication procedures that allow fixed and Mode II white space
   devices to be assured that the data they receive is from an authorized
   source.

   (4) Applications for certification of white space devices shall include
   a high level operational description of the technologies and measures
   that are incorporated in the device to comply with the security
   requirements of this section. In addition, applications for
   certification of fixed and Mode II white space devices shall identify
   at least one of the white space databases operated by a designated
   white space database administrator that the device will access for
   channel availability and affirm that the device will conform to the
   communications security methods used by that database.

   [ 80 FR 73070 , Nov. 23, 2015, as amended at  81 FR 4974 , Jan. 29, 2016;
    82 FR 41559 , Sept. 1, 2017;  84 FR 34797 , July 19, 2019]