Sec.  21.938   BTA and PSA technical and interference provisions.

   

   (a) BTA or PSA authorization holders are expected to cooperate with
   one another by designing their stations in a manner that protects
   service in adjoining BTAs and PSAs including consideration of
   interference abatement techniques such as cross polarization,
   frequency offset, directional antennas, antenna beam tilt, EIRP
   decrease, reduction of antenna height, and terrain shielding.

   (b) Unless the affected parties have executed a written interference
   agreement in accordance with Sec. 21.937, and subject to the provisions of
   Sec. Sec. 21.909, 21.913, 21.949, 74.939 of this chapter, 74.949 of this
   chapter and 74.985 of this chapter regarding the protection of
   response station hubs, booster service areas and 125 kHz channels from
   harmful electromagnetic interference, stations licensed to a BTA or
   PSA authorization holder must not cause harmful electromagnetic
   interference to the following:

   (1) The protected service area of other authorization holders in
   adjoining BTAs or PSAs.

   (2) The 56.33 km (35 mile) protected service areas of authorized or
   previously proposed MDS stations (incumbents).

   (3) Registered receive sites and protected service areas of authorized
   or previously proposed stations in the Instructional Television Fixed
   Service pursuant to the manner in which interference is defined in
   Sec. 74.903(a).

   (c)(1) ITFS applicants may locate a new station in an unused portion
   of a BTA or PSA where interference to a previously-proposed or
   authorized MDS station of a BTA or PSA authorization holder would not
   be predicted.

   (2) With respect to ITFS applications only and for purposes of
   determining the existence of harmful electromagnetic interference as
   caused to MDS stations licensed to BTA or PSA authorization holders by
   subsequently proposed ITFS stations within that BTA, MDS stations
   licensed to BTA and PSA authorization holders and will have a
   protected service area of 56.33 km (35 miles), centered on the antenna
   site of the MDS stations.

   (3) The 56.33 km (35 mile) protected service area afforded to a
   previously-proposed or authorized MDS station of a BTA or PSA
   authorization holder with respect to a subsequently proposed ITFS
   station is entitled to the interference protection standards of
   Sec. 21.902.

   (4) An ITFS station authorized before September 15, 1995 may be
   modified, provided the power flux density of that station does not
   exceed -73 dBW/m 2 (or the appropriate value for bandwidth other than
   6 MHz) at locations along the 56.33 km (35 mile) circle centered on
   the then-existing transmitting antenna site or service area of a
   collocated incumbent MDS station, as applicable.

   (d) Unless the affected parties have executed a written interference
   agreement in accordance with Sec. 21.937, it shall be the responsibility
   of a BTA or PSA authorization holder to correct at its expense any
   condition of harmful electromagnetic interference caused to authorized
   MDS service at locations within other BTAs or PSAs or within the 56.33
   km (35 mile) protected service areas of authorized or previously
   proposed ITFS and MDS stations (incumbents), or at authorized or
   previously proposed ITFS receive sites.

   (e) Unless specifically excepted, BTA or PSA authorization holders are
   governed by the interference protection and other technical provisions
   applicable to MDS.

   (f) The calculated free space power flux density from an MDS station,
   other than an incumbent MDS station, may not exceed -73 dBW/m 2 (or
   the appropriate value for bandwidth other than 6 MHz) at locations on
   BTA or PSA boundaries for which there is an unobstructed signal path
   from the transmitting antenna to the boundary, unless the applicant
   has obtained the written consent of the authorization holder for the
   affected BTA or PSA.

   (g)(1) Authorization holders for BTAs or PSAs must notify
   authorization holders of adjoining areas of their application filings
   for new or modified stations; provided the proposed facility would
   produce an unobstructed signal path anywhere within the adjoining BTA
   or PSA.

   (2) This service of written notification must include a copy of the
   FCC application and occur on or before the date the application is
   filed with the Commission.

   (3) With regard to incumbent MDS stations, authorization holders for
   BTAs or PSAs must comply with the requirements of Sec. 21.902.

   (h) Where a PSA adjoins a BTA and both authorizations are held by the
   same individual or entity, the PSA shall be considered an extension of
   the protected service area of the BTA regarding the interference
   protection, limiting signal strength, and notification provisions of
   this section.

   [ 60 FR 36557 , July 17, 1995, as amended at  60 FR 57367 , Nov. 15, 1995;
    63 FR 65112 , Nov. 25, 1998;  64 FR 63737 , Nov. 22, 1999]