PART 22 PUBLIC MOBILE SERVICES
In-Building systems and Signal Boosters

[FCC Rules as of 12-04-2001]

Always refer to current FCC rules for most valid information.

Special note: In Part 22, the FCC places different, but interrelated meanings on "in-building" and "signal booster".

"In-building" not only encompasses signal booster devices used for in-building applications but any other form of in-building RF distribution system.

"Signal Boosters", by that specific name, are limited to use on paging channels as per 22.527, 22.535(f), 22.537 (g) and 22.537(h) and may be used for outdoor coverage 'fill-in'.

22.99 Definitions.

In-building radiation systems. Supplementary systems comprising low power transmitters, receivers, indoor antennas and/or leaky coaxial cable radiators, designed to improve service reliability inside buildings or structures located within the service areas of stations in the Public Mobile Services.

Signal booster. A stationary device that automatically reradiates signals from base transmitters without channel translation, for the purpose of improving the reliability of existing service by increasing the signal strength in dead spots.

Dead spots. Small areas within a service area where the field strength is lower than the minimum level for reliable service. Service within dead spots is presumed.

22.165 Additional transmitters for existing systems.
A licensee may operate additional transmitters at additional locations on the same channel or channel block as its existing system without obtaining prior Commission approval provided:

(a) International coordination. The locations and/or technical parameters of the additional transmitters are such that individual coordination of the channel assignment(s) with a foreign administration, under applicable inter-national agreements and rules in this part, is not required.

(b) Antenna structure registration. Certain antenna structures must be registered with the Commission prior to construction or alteration. Registration requirements are contained in part 17 of this chapter.

(c) Environmental. The additional transmitters must not have a significant environmental effect as defined by 1.1301 through 1.1319 of this chapter.

(d) Paging and Radiotelephone Service. The provisions in this paragraph apply for stations in the Paging and Radio-telephone Service.

(1) The interfering contours of the additional transmitter(s) must be to-tally encompassed by the composite interfering contour of the existing station (or stations under common control of the applicant) on the same channel, except that this limitation does not apply to nationwide network paging stations or in-building radiation systems.

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22.352 (c)(7) Protection from interference.

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(c) Situations in which no protection is afforded. Except as provided elsewhere in this part, no protection from interference is afforded in the following situations:
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(7) In-building radiation systems. No protection is provided against interference to the service of in-building radiation systems (see 22.383).

22.373 Access to transmitters.
Unless otherwise provided in this part, the design and installation of transmitters in the Public Mobile Services must meet the requirements of this section.

(a) Transmitters and control points, other than those used with in-building radiation systems, must be installed such that they are readily accessible only to persons authorized by the licensee to operate or service them.

(b) Transmitters must be designed and installed such that any adjustments or controls that could cause the transmitter to deviate from its authorized operating parameters are readily accessible only to persons authorized by the licensee to make such adjustments.

(c) Transmitters (other than hand-carried or pack-carried mobile transmitters) and control points must be equipped with a means of indicating when the control circuitry has been put in a condition that should cause the transmitter to radiate.

(d) Transmitters must be designed such that they can be turned off independently of any remote control circuits.

(e) Transmitters used with in-building radiation systems must be installed such that, to the extent possible, they are readily accessible only to persons authorized by the licensee to access them.

(f) Transmitters used with in-building radiation systems must be designed such that, in the event an unauthorized person does gain access, that person can not cause the transmitter to deviate from its authorized operating parameters in such a way as to cause interference to other stations.

Sec. 22.377 Certification of transmitters.
Except as provided in paragraph (b) of this section, transmitters used in the Public Mobile Services, including those used with signal boosters, in-building radiation systems and cellular repeaters, must be certificated for use in the radio services regulated under this part. Transmitters must be certificated when the station is ready for service, not necessarily at the time of filing an application.

(a) The FCC may list as certificated only transmitters that are capable of meeting all technical requirements of the rules governing the service in which they will operate. The procedure for obtaining certification is set forth in part 2 of this chapter.

(b) Transmitters operating under a developmental authorization (see subpart D of this part) do not have to be certificated.

(c) In addition to the technical standards contained in this part, transmitters intended for operation in the Cellular Radiotelephone Service must be designed to comply with the technical requirements contained in the cellular system compatibility specification (see Sec. 22.933) and the electronic serial number rule (see Sec. 22.919).

22.383 In-building radiation systems.
Licensees may install and operate in-building radiation systems without applying for authorization or notifying the FCC, provided that the locations of the in-building radiation systems are within the protected service area of the licensee’s authorized transmitter(s) on the same channel or channel block.

22.527 Signal boosters.
Licensees may install and operate signal boosters on channels listed in 22.531 (i.e. paging channels) only in accordance with the provisions of 22.165 governing additional transmitters for existing systems. Licensees must not allow any signal booster that they operate to cause interference to the service or operation of any other authorized stations or systems.

Sec. 22.535(f) Effective radiated power limits.
The effective radiated power (ERP) of transmitters operating on the channels listed in Sec. 22.531 must not exceed the limits in this section.
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(f) Signal boosters. The effective radiated power of signal boosters must not exceed 5 watts ERP under any normal operating condition.

22.537(G) & 22.537(h) Technical channel assignment criteria.
The rules in this section establish technical assignment criteria for the channels listed in 22.531. These criteria permit channel assignments to be made in a manner such that reception by public paging receivers of signals from base transmitters, within the service area of such base transmitters, is protected from interference caused by the operation of independent co-channel base transmitters.
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(g) In-building radiation systems. The locations of in-building radiation systems must be within the service contour(s) of the licensee’s authorized transmitter(s) on the same channel. In-building radiation systems are not protected facilities, and therefore do not have service or interfering contours.

(h) Signal boosters on 931 MHz channels. For the purpose of compliance with 22.165 and notwithstanding paragraphs (e) and (f) of this section, signal boosters operating on the 931 MHz channels with an antenna HAAT not exceeding 30 meters (98 feet) are deemed to have as a service contour a circle with a radius of 1.0 kilometer (0.6 mile) and as an interfering contour a circle with a radius of 10 kilometers (6.2 miles).

 (Comment: "Certificated" has replaced 'type approved' as the term meaning the FCC has approved the transmitter for this radio service. Signal boosters used in this radio service must be FCC approved, regardless of output power.)

Last Update: September 11, 2005

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