RULES and REGULATIONS

                       FEDERAL COMMUNICATIONS COMMISSION

                           47 CFR Parts 2, 15, and 90

                        [Gen. Docket 81-413;  FCC 85-245]

Authorization of Spread Spectrum Systems Under Parts 15 and 90 of the FCC Rules
                                and Regulations

                             Tuesday, June 18, 1985

ACTION: Final rules.

SUMMARY: This action changes Part 15 of the Rules to allow spread spectrum systems to operate in the ISM bands at 902-928, 
2400-2483.5 and 5725-5850 MHz on a noninterference basis to other authorized users of these bands.   The maximum output power of 
these systems is limited to 1 watt.

 Changes are also made to Part 90 of the Rules to allow law enforcement officers to operate direct sequence and time hopping spread 
spectrum transmitters on selected Public Safety Radio Service frequencies.   To protect the agents involved in these operations, 
the station identification requirement, which was previously required for these operations, has been dropped.   Approval from the 
local area coordinator, of the Police Radio Service of the district in which the license and equipment are to be used, must be 
first obtained before a licensed law enforcement officer can operate a spread spectrum transmitter on these frequencies.

EFFECTIVE DATE: June 15, 1985.

*25235 ADDRESS: Federal Communications Commission, Washington, D.C., 20554.

FOR FURTHER INFORMATION CONTACT:

  Dr. Joseph McNulty, (301) 725-1585

  Dr. Michael Marcus, (202) 632-7040

SUPPLEMENTARY INFORMATION:

List of Subjects

47 CFR Part 2

 Radio.

47 CFR Part 15

 Radio frequency devices.

47 CFR Part 90

 Private land mobile radio services, Radio.

First Report and Order

 In the matter of authorization of spread spectrum and other wideband emissions not presently provided for in the FCC Rules and 
Regulations;  Gen. Docket No. 81-413.
 Adopted:  May 9, 1985.
 Released:  May 24, 1985.



 By the Commission.

Introduction and Summary

 1. Spread spectrum modulation is a wideband modulation which was originally developed for military applications but which has 
several interesting civil applications. [FN1]  This technology has been implicitly forbidden by the FCC rules with a few limited 
exceptions.   On June 30, 1981, the Commission adopted a Notice of Inquiry ("Inquiry") [FN2] in this proceeding seeking comments on 
a rule structure that would permit civil use of this technology. [FN3]

  FN1 The spreading or dilution of the energy in spread spectrum systems over a wide bandwidth results in several possible 
advantages:  short range overlays on other emissions, resistance to interference from other emissions, and low detectability.   
While it is not anticipated that spread spectrum will replace other types of modulations in general, the unique characteristics of 
spread spectrum offer important options for the communications system designer.

  FN2 87 FCC 2d 876.

  FN3 A companion Notice of Proposed Rulemaking was adopted in Docket 81-414 proposing use of spread spectrum in the Amateur Radio 
Service and has been implemented, in part, in a Report and Order we are adopting today.
 2. Based on the comments received in the Inquiry, we adopted a Further Notice of Inquiry and Notice of Proposed Rulemaking 
("Further Notice"), [FN4] on May 26, 1984, proposing specific rules for spread spectrum in Parts 15 and 90 of our Rules.   In this 
First Report and Order we are adopting some of the proposals of the Further Notice with some modification.   The remaining issues 
in the Further Notice raised significant controversy in the Comments and we are continuing to review these to see what action is 
appropriate.

  FN4 49 FR 21951,   FCC 2d   .
 3. In general, the replies to the Inquiry favored the Commission's effort to introduce this communications technique.   However, 
many of the respondents were concerned that implementation of this technique might cause unacceptable interference to existing 
services unless its development was restricted to low- powered, limited range applications and that the allowable frequencies and 
powers were carefully chosen.   Because the technology is new and unfamiliar to the civilian sector, many urged the Commission to 
proceed slowly with its implementation until sufficient experience in the identification and measurement of spread spectrum signals 
had been gained and an assessment had been made of their interference potential.   Without this information, the majority of the 
respondents were firmly against a general overlay of spread spectrum systems upon existing services.   However, few objected to the 
use of these systems in an overlay fashion, as long as they were restricted to low- power and limited range applications.
 4. From the responses to the Inquiry the FCC developed rulemaking proposals for the operation of spread spectrum systems as 
licensed devices in the Police Radio Service under Part 90 of the Rules and as low-powered, limited range devices to be authorized 
under Part 15 of the Rules.   As a further incentive for the development of this technology, the rules would allow spread spectrum 
systems of higher power to operate in the 902-928, 2400-2483.5 and 5725-5875 MHz Industrial, Scientific and Medical ISM bands.   
However, the record was still not sufficiently complete to allow a drafting of the equipment authorization procedures and 
measurement standards that would be used to determine the equipment compliance for these systems.   Accordingly, the Further Notice 
was released by the Commission on May 21, 1984 to solicit further information on the equipment authorization and measurement 
procedures and to obtain comments on the proposed rules.

Discussion of Comments and Reply Comments

 5. Thirty-seven comments and fifteen reply comments were filed in response to the Further Notice. These came from a wide range of 
parties and interest groups.   A list of those filing comments is contained in Appendix A. [FN5] 6 Along with comments from 
individuals, comments were received from amateur radio, broadcasting, business and industry, cordless telephone manufacturing, 
police and public safety, and radiopositioning and radionavigation interest groups.   Most of the comments which were received were 
directed to issues or questions posed in the Further Notice and no significant new matters relative to the proceeding were raised.

  FN5 Some of the comments which were received were not pertinent to this proceeding.   ONI, Racal-Decca Survey, Inc., Sercel Inc. 
and Teledyne Hastings-Raydist all filed comments which were concerned solely with radiolocation operations in the 1600-3000 kHz 
band.   These comments are outside the scope of this proceeding which is concerned with spread spectrum systems operating on 
frequencies above 70 MHz. The comments of these parties will be considered under Docket 84-874 which is dealing with radiolocation 
allocations in the 1900-2000 kHz band.

  FN6 Exxon's comments which described a downward looking impulse radar system being developed under a Special Temporary 
Authorization from the Private Radio Bureau, were also outside the scope of this proceeding.   Although the Exxon system operates 
on frequencies between 100 and 1000 MHz, its relatively high output power (33 watts) and antenna height (to be operated from a 
hovering aircraft) may require a special allocation under Part 2 of the Rules rather than any consideration in this proceeding 
under Part 15. We have not received sufficient information in this proceeding in the type of system Exxon proposes to formulate a 
specific proposal.
 6. Many of the respondents favored the proposed authorization of spread spectrum for low-power limited range communications 
devices and considered the proposed rules conservative enough for immediate adoption.   Others, including broadcasting interests in 
particular, expressed concern over interference to their services from these devices.   Though not opposing the Commission's action 
in general, they did oppose the overlay of spread spectrum systems on the frequency bands in which they are operating.



 7. More specifically, broadcasting groups and some large consumer product manufacturers (RCA, GE and others) suggested that the 
present level of television service would be seriously degraded if spread spectrum systems were allowed to operate in the 
television bands.   Even though the proposed rules were formulated to offer to this service a level of protection from direct 
sequence systems equivalent to a TASO 3 level of reception at the Grade A service contour, it was argued that an interference level 
based on this criterion would produce a degradation of picture quality for those living outside of this contour.   It was also 
argued that interference from these systems would cause a loss of picture quality in those *25236 areas, both within and outside 
the Grade A service contour, where reception is superior to TASO 3 at the present time.
 8. COMSAT, STC and AT&T were concerned that some microwave, cellular and satellite facilities may be especially vulnerable to 
interference from spread spectrum devices particularly in those services where wide bandwidths are employed and weak signals are 
involved.
 9. ARRL and several individual amateurs were concerned about possible interference from spread spectrum systems operating in the 
amateur bands at 144-146, 220-225 and 420-450 MHz. They argued that since amateurs operate in residential environments, which could 
conceivably contain many Part 15 spread spectrum devices, their systems would be more susceptible to interference from these 
devices than those in other services which are operating principally in nonresidential environments.   It was further argued that 
in many amateur operations the level of the ambient noise is critical since they are often dealing with very weak signals which in 
many cases are barely on the fringes of detection.   These signals can be easily masked and lost in interference coming from other 
sources.
 10. Of the parties submitting comments that opposed the proposed authorization of spread spectrum systems, RCA was the only one 
that supported its position with analysis.   RCA's analysis dealt with possible interference to FM and television broadcasting from 
spread spectrum systems operating in the broadcast bands.   However this is not a consideration in this item which is concerned 
with the authorization of spread spectrum systems in the ISM bands and on Public Safety Radio frequencies.
 11. Several police and public safety groups filed comments on the proposed authorization of spread spectrum systems in the Police 
Radio Service bands under Part 90 of the Rules.   The major concern of all of these parties was not interference to their service 
from the police use of spread spectrum systems in these bands, but rather from other spread spectrum systems that would be 
authorized to use these bands on a secondary basis.   The only major difficulty that was foreseen with the police use of spread 
spectrum systems in these bands was a possible increase in band congestion.   To ease this congestion, as well as to provide a 
broader range of frequencies that could be used for covert operations, it was suggested that the proposed Part 90 spread spectrum 
authorization be extended to all frequencies in the Public Safety Radio Services.
 12. Both APCO and the County of Orange, California, thought that there was no need to increase the present power limit of 2 watts 
for fast frequency hopping systems operating in the Public Safety bands and that the proposed 15 watt limit for these systems 
should be reduced to 2 watts.   They stated that a 2 watt limit should be sufficient for all of their present and future frequency 
hopping needs and can easily be increased later if necessary.   They also requested that the station identification requirement of 
s 90.19(g)(3) of the present Rules should be eliminated for undercover operations, since it not only jeopardizes the security of 
these operations but it also creates a real danger to the agents involved.
 We have long noted that this is an ambiguous rule, providing use "without special authorization", while at the same time requiring 
"station identification".   This inconsistency has led to some problems which would no doubt be perpetuated and possibly increased 
by the rules as proposed.   We would suggest some special type of provision which would allow the frequency coordinator to 
recommend or assign these channels on a secondary basis, but without the necessity for a formal license, which defeats the intent 
of maintaining security through anonymity. [FN7]

  FN7 APCO Comments, page 5.
 County of Orange also requested the use of other Public Safety frequencies for surveillance operations using modulations other 
than spread spectrum only if approval or the coordinator had been obtained.
 13. No serious objections were raised to the authorization of spread spectrum systems in the 902-928, 2400-2483.5 and 5725-5875 
MHz ISM bands as long as these operations did not cause interference to systems that have been authorized the use of these bands 
under other Parts of the Rules.   Both NTIA and GE thought that there should be a cap on the maximum output power which these 
systems can use.   NTIA suggested a power limit of 10 watts, GE a limit of 7 watts.   COMSAT expressed concern that use of 
5850-5875 MHz might cause interference to the new Fixed Satellite Service allocation in that band.
 14. In the Further Notice, we asked if the proposed rules would be sufficient to allow the development of wireless data terminal 
systems or whether more power should be allowed for these devices, either by the creation of a special business-industrial class 
permission under Part 15 or by authorizing them in one of the licensed services.   Hewlett-Packard, which has been developing these 
systems on an experimental basis under Part 5 of the Rules, suggested that the power limits proposed in the Further Notice are not 
sufficient for these devices.   Based upon the field strengths which they consider to be adequate for the development of these 
devices, the proposed level for direct sequence emissions of 33 uV/m at 3 meters per 4 MHz of bandwidth is at least 10 times too 
small.   If this power limit cannot be raised for these systems, then Hewlett-Packard suggested that wireless data terminals be 
licensed in the Private Land Mobile Radio Services as a separate service under Part 90 of the Rules.   RCA felt that since these 
terminals would be mainly business and not consumer devices, they should be licensed under Part 94 of the Rules for the Private 
Operational-Fixed Microwave Service, rather than under Part 15.
 15. Comments were also solicited in the Further Notice concerning the feasibility of authorizing carrier current spread spectrum 
systems.   Hewlett- Packard has already made measurements on an experimental 5 milliwatt system and finds that the technology is 
very promising.   Hewlett-Packard can foresee little interference to other authorized services from these systems as long as the 
carrier current operations are confined to large buildings or areas within buildings which have their power supplied from 
transformers rather than by a direct connection to the AC power lines.   These power transformers with their large interwinding 
capacitances would prevent much of the RF energy generated by the spread spectrum systems from being fed back into the AC power 
lines. Carrier current systems are limited to operation on frequencies below 20 MHz because of the excessive signal losses that 
occur when operated on frequencies above this.   We find the two Hewlett-Packard suggestions to be promising new applications of 



this technology and will consider in the near future further action to authorize their use.
  16. A request was made in the Further Notice for assistance in developing measurement procedures for spread spectrum systems.   
Although many parties addressed this matter, there was little consensus as to what these procedures should be.   However, most 
parties did agree that a measurement bandwidth must be specified before any meaningful measurement procedures could be drawn up.
 17. Some cordless telephone manufacturers expressed concern in the *25237 comments that the proposed spread spectrum 
authorizations could prejudice their petition for 2 MHz of spectrum in the 900 MHz band. [FN8]  They felt that the present action 
by the Commission might force them to utilize a technology which they do not have the resources at the present time to develop, and 
which may not provide sufficient power for their needs.

  FN8 See Electronic Industries Association Petition for Rulemaking, RM 4780;   (requesting an allocation of 2 MHz of spectrum for 
cordless telephone use in the 900 MHz band) (filed March 1, 1984.)
 18. Of the bands presented above, only two were addressed in a degree which allows for a well reasoned decision.   We are 
deferring without prejudice action on all other issues addressed in the Further Notice. The two issues to be decided at this time 
are the use of spread spectrum in the Police Radio Service and the use of spread spectrum in the ISM bands.

Findings

Spread Spectrum in the Police Radio Service

 19. The record of this proceeding is sufficiently complete at the present time to enable us to authorize frequency hopping systems 
to be operated on a limited basis on certain frequencies in the Public Safety Radio Service.   This would expand the provisions 
currently given in s 90.19(g)(3).   This authorization is limited to law enforcement officers and its purpose is to allow them to 
set up communication links on these frequencies that can be used in connection with physical surveillance, stakeouts, raids and 
other such activities.   Operation on these frequencies will be on a noninterference basis to the operations of other licensees who 
have been authorized the use of these frequencies under other sections of the Part 90 Rules.   In addition, their use of these 
frequencies is subject to the approval of the applicable frequency coordinators of the Public Safety Radio Service of the district 
in which the license and equipment are to be used and if non-police Public Safety frequencies are to be used the coordination of 
the other service's coordinator is also needed.   The changes to Part 90 of the Rules and Regulations to accomplish this 
authorization are presented in Appendix B.
 20. Since spread spectrum transmissions are not readily detectable by criminals who may be monitoring the air waves and since they 
are difficult to jam, this authorization gives law enforcement officers an extremely valuable tool to use in their operations.   
Federal law enforcement agencies operating radio systems under 47 U.S.C. 305 are already authorized by the National 
Telecommunications and Information Administration to use spread spectrum in their operations on a case-by-case basis.   These new 
rules extend this same capability to state and local law enforcement agencies as well.
 21. Under the new Part 90 Rules frequency hopping systems with a maximum output power of 2 watts are allowed to operate on any of 
the frequencies presently available to the Public Safety Services as listed in Subpart B of Part 90 of the Rules.   The 2 watt 
power limit for these systems is the same as that which is permitted for all present users of these frequencies, on a "without 
prior FCC approval" basis, irrespective of the modulation which they may be using.   Hence, frequency hopping systems which are 
operating on these frequencies are not expected to cause harmful interference to other users of this spectrum.   The 2 watt output 
power limit applies to all frequency hopping systems that are operating on these frequencies no matter what their hop rate is.   
Requests to use higher powers will be considered on a case-by-case basis for special temporary authorizations.   Appendix C gives 
guidelines for coordinators to use in considering requests to use frequency hopping systems which we feel should be adequate to 
prevent harmful interference.
 22. While the Commission and some law enforcement agencies have experience with frequency hopping systems, at this time there is 
very little non-military experience with direct sequence systems.   We have traditionally been extremely careful in minimizing the 
likelihood of harmful interference to critical public safety systems.   Thus we shall defer at the moment the permanent 
authorization of direct sequence systems for police use until we have more data available. We plan to conduct tests at our 
Laboratory and will invite representatives of the police community to participate.   Pending further action in this area, 
experimental and developmental licenses and special temporary authorization will be available to manufacturers and police licensees 
who wish to try direct sequence systems.
 23. Both APCO and the County of Orange, California have brought to our attention the inherent danger that the station 
identification requirement of s 90.19(g)(3) of the present rules poses to both the security of undercover operations and the safety 
of the agents involved.   Since the frequencies allocated for these operations can only be used by the law enforcement officers for 
spread spectrum, and, since approval must be obtained from the applicable frequency coordinators prior to the use of these 
frequencies for police spread spectrum operations, it would seem that any unauthorized use of these frequencies can be readily 
detected.   Thus, we feel that the station identification requirement present in this section of the Rules is superfluous and can 
be deleted safely.

Spread Spectrum in the ISM Bands

 24. Spread spectrum systems are also being authorized under Part 15 for general usage in the 902-928 MHz, 2400-2483.5 MHz and 
5725-5850 MHz ISM bands. Due to COMSAT's concern in its comments about the possibility for interference to the Fixed Satellite 
Service allocated at 5850-5875 MHz, we have excluded these frequencies from spread spectrum usage.   These systems may operate 
within these bands with a maximum output power of 1 watt.   RF output power outside these bands over any 100 kHz bandwidth must be 
20 dB below that in any 100 kHz bandwidth within the band which contains the highest level of the desired power.   For 
certification of spread spectrum equipment that is to be used in these bands, the applicant applying for certification must 



demonstrate by either measurement or analysis that this limit has been met.   Spread spectrum systems are allowed to operate within 
the ISM bands only on a noninterference basis to other operations that have been authorized the use of these bands under other 
Parts of the Rules.   They must not cause any harmful interference to these operations and must accept any interference which these 
systems may cause to their own operations. [FN9]

  FN9 NTIA has recently studied the current and potential electromagnetic usage of these three bands.   Their findings are 
contained in the following reports.
  See Bohdan Bulawka, "Spectrum Resource Assessment in the 902-928 MHz Band", NTIA Report 80-46, September 1980;
  See Robert T. Watson, "Spectrum Resource Assessment in the 2300-2450 MHz Band", NTIA Report 81-78, September 1981;
  See William B. Grant, John C. Carroll and Charles J. Chilton, "Spectrum Resource Assessment in the 5650-5925 MHz Band", NTIA 
Report 83-115, January 1983.
 25. Although both NTIA and GE found no great difficulty with spread spectrum systems operating within the ISM bands with maximum 
output powers of 7 watts, GE did take exception to the opening of these bands to communications systems which have been accustomed 
to operation with some degree of protection from *25238 interference.   GE fears that the steady encroachment on these bands by 
other services will eventually lead to petitions from these other users for protection from interference from ISM devices.   This 
would be unfortunate since industry is constantly finding new uses of these frequencies in many diverse applications ranging from 
coal desulphurization to food sterilization.
 26. We appreciate GE's concern in this regard and acknowledge the danger in opening these bands to high power communications 
devices.   In addition, Part 15 of the Rules is intended to provide authorization for low power communications devices and not for 
communications devices of considerable output power.   To open the Part 15 rules to high-powered communications devices, even in a 
band where other authorized high powered industrial and government equipment is already operating, would not be in keeping with the 
purpose of this Part of the Rules.   Therefore we have reduced considerably the original power limits that we proposed for systems 
operating in these bands, even below the levels proposed by NTIA and GE. Even at that, the limit of 1 watt that we are allowing for 
these systems is still much higher than the level of power that we would normally authorize for devices.   However, both because of 
the unique nature of these bands and because the systems being authorized under these rules will be spreading this energy over a 
wide bandwidth, we believe an output power level of 1 watt is justified.   In view of the 1 watt power limit which we are adopting 
in the final rules we believe the possibility of these systems interfering with other authorized users of these bands is small.

Conclusion

 27. The rules which are adopted here for spread spectrum systems operating in the Police Radio Service and in the ISM bands have 
been kept deliberately conservative in order to minimize any possibility of interference from these systems to existing services.   
As a further safeguard, all spread spectrum devices which will be permitted under the Part 15 rules proposed in this Report and 
Order are required to be certified as a prerequisite to marketing.   The Rules for the certification of Part 15 low power 
communication devices are given in the Rules and Regulations under Part 15, Subpart B. See also Part 2, Subpart J, for general 
certification and type acceptance procedures.   In addition, the Commission has the discretionary authority to call in sample 
devices for testing as part of the certification process.   As we have done in the past with cordless telephones, CB radios, home 
computers and other devices, we expect to engage in a thorough sampling program until we are confident that the manufacturers have 
gained sufficient knowledge and skill in building these devices, so that they pose no potential interference problems to other uses 
of the radio spectrum.   The procedures for the type acceptance of equipment to be used in the Police Radio Service are given in s 
90.203 of the Rules and in Subpart J of Part 2.
 28. With the above mentioned safeguards that have been built into the Rules, we do not feel that requiring spread spectrum 
transmitters to use automatic identifiers is warranted at the present time.   However in the future, when a much broader 
authorization of spread spectrum systems may be considered, we may wish to consider some form of transmission identifier to assist 
us in identifying and locating units which may be causing interference.
 29. We are deferring without prejudice action on the remaining issues which were discussed in the Further Notice, such as, the 
operation of low powered spread spectrum devices on frequencies above 70 MHz, the measurement procedures to be used in the 
certification of these devices and the possibility of licensing spread spectrum wireless data terminals and carrier current systems 
under other Parts of the Rules.   For further information about this Report and Order contact, Dr. Joseph McNulty at (301) 725-1585 
or Dr. Michael Marcus at (202) 632-7040.

Regulatory Flexibility Final Analysis

 30. Reason for Action. The Commission believes that its rules and policies should be reviewed in the context of current social, 
technological and financial environments in which licensees and applicants operate, so that service to the public may be 
facilitated while at least regulatory cost is imposed.   It is in this light that it is considering modification of its Part 15 and 
Part 90 rules.
 31. The Objectives. The Commission proposes to accommodate spread spectrum systems by reducing regulation to the maximum extent 
feasible.   The Commission believes that such action will lead to a more rapid development of spread spectrum technology in the 
civilian sector.
 32. Legal basis. Action proposed herein is taken pursuant to sections 4(i), 7(a), 302 and 303(r) of the Communications Act of 
1934, as amended.
 33. Description, potential impact and number of small entities affected. The ability to develop communications equipment which 
employs spread spectrum modulation techniques as described in the attached Rules will be beneficial to all entities which are 
involved.   Therefore, we foresee only positive impacts on small entities.
 34. Recording, record keeping and other compliance requirements. The modifications to Part 15 and 90 of the Rules would require 



record generation by the manufacturer sufficient to meet the usual equipment authorization requirements.   Additionally, the 
modifications of the part 90 Rules require a simple onetime notification to the applicable frequency coordinators of the district 
in which the license and equipment are to be used.
 35. Federal rules which overlap, duplicate or conflict with this rule. None.
 36. Any significant alternatives minimizing impact on small entities and consistent with the stated objective. None.
 37. Accordingly, it is ordered, that effective June 15, 1985, Part 15 and Part 90 of the Rules and Regulations are amended as set 
forth in the attached Appendix B. The authority for this action is found in section 4(i), 7(a), 302, and 303(r) of the 
Communications Act of 1934, as amended.
Federal Communications Commission.

William J. Tricarico,

Secretary.

Appendix A--List of Parties Supplying Comments and Reply Comments to the Further Notice

 The following parties supplied Comments to the Further Notice of Inquiry and Notice of Proposed Rulemaking:
 Aeronautical Radio, Inc., (ARINC)
 American Radio Relay League, (ARRL)
 American Telephone and Telegraph Company, (AT&T)
 Associated Public-Safety Communications Officers, Inc., (APCO)
 Association of Maximum Service Telecasters, (MST)
 California Public Safety-Radio Association, Inc., (CPRA)
 Communications Satellite Corporation, (COMSAT)
 Jonathan C. Dahm
 Joint submission by Dr. George R. Cooper and Dr. William W. Chapman
 Del Norte Technology, Inc.
 Door Operator & Remote Controls Manufacturers Association, (DORCMA)
 Dynascan Corporation
 *25239 The Consumer Electronics Group of the Electronic Industries Association, (EIA/CEG)
 The Personal Communications Section, Telecommunications Group, of the Electronic Industries Association
 Exxon Communications Company
 General Electrics, (GE)
 Geostar Corporation
 Hewlett-Packaged, (HP)
 County of Los Angeles, Department of Communications
 Mura Corporation
 National Association of Broadcasters, (NAB)
 National Association of Business and Educational Radio, Inc., (NABER)
 National Broadcasting Company, Inc., (NBC)
 Offshore Navigation, Inc., (ONI)
 Radscan, Inc.
 RCA Corporation, (RCA)
 Ronald E. Reder
 Cortland E. Richmond
 Satellite Television Corporation, (STC)
 Schenectady Amateur Radio Association, Inc.
 Sercel Incorporated
 Telesciences International Limited
 Joint submission by 15 telephone companies
 Texas VHF-FM Society
 U.S. Dept. of Commerce, National Telecommunications and Information Administration, (NTIA)
 Wilkins Engineering
 Zenith Electronics Corporation
 The following parties supplied Reply Comments to the Further Notice of Inquiry and Notice of Proposed Rulemaking:
 American Petrolum Institute, (API)
 American Telephone and Telegraph Company, (AT&T)
 Association of Maximum Service Telecasters, (MST)
 Communications Satellite Corporation, (COMSAT)
 County of Orange, California
 Del Norte Technology, Inc.
 The Personal Communications Section, Telecommunications Group, of the Electronic Industries Association
 General Electric, (GE)
 Hewlett-Packard, (HP)
 National Association of Broadcasters, (NAB)
 Offshore Navigation, Inc., (ONI)



 Racal-Decca Survey, Inc.
 Radscan, Inc.
 Teledyne Hastings-Raydist
 Joint submission by 19 telephone companies
 U.S. Dept. of Commerce, National Telecommunications and Information Administration, (NTIA)

Appendix B--Changes to Parts 2, 15 and 90 of the FCC Rules and Regulations

PART 2--[AMENDED]

 A. Part 2 of Chapter I of Title 47 of the Code of Federal Regulations is amended as follows:
 The authority citation for Part 2 continues to read:

 Authority: Section 4(i), 7(a), 302, and 303(r) of the Communications Act of 1934, as amended.

 1. Section 2.1, General Definitions, is amended by inserting the following definitions in alphabetical order.

s 2.1 [Amended]

* * * * *
 Direct Sequence Systems. A direct sequence system is a spread spectrum system in which the incoming information is usually 
digitized, if it is not already in a binary format, and modulo 2 added to a higher speed code sequence.   The combined information 
and code are then used to modulate a RF carrier.   Since the high speed code sequence dominates the modulating function, it is the 
direct cause of the wide spreading of the transmitted signal.
* * * * *
 Frequency Hopping Systems. A frequency hopping system is a spread spectrum system in which the carrier is modulated with the coded 
information in a conventional manner causing a conventional spreading of the RF energy about the carrier frequency.   However, the 
frequency of the carrier is not fixed but changes at fixed intervals under the direction of a pseudorandom coded sequence.   The 
wide RF bandwidth needed by such a system is not required by a spreading of the RF energy about the carrier but rather to 
accommodate the range of frequencies to which the carrier frequency can hop.
* * * * *
 Pulsed FM Systems. A pulsed FM system is a spread spectrum system in which a RF carrier is modulated with a fixed period and fixed 
duty cycle sequence.   At the beginning of each transmitted pulse, the carrier frequency is frequency modulated causing an 
additional spreading of the carrier.   The pattern of the frequency modulation will depend upon the spreading function which is 
chosen. In some systems the spreading function is a linear FM chirp sweep, sweeping either up or down in frequency.
* * * * *
 Spread Spectrum Systems. A spread spectrum system is an information bearing communications system in which:  (1) Information is 
conveyed by modulation of a carrier by some conventional means, (2) the bandwidth is deliberately widened by means of a spreading 
function over that which would be needed to transmit the information alone. (In some spread spectrum systems, a portion of the 
information being conveyed by the system may be contained in the spreading function.)
* * * * *
 Time Hopping Systems. A time hopping system is a spread spectrum system in which the period and duty cycle of a pulsed RF carrier 
are varied in a pseudorandom manner under the control of a coded sequence.   Time hopping is often used effectively with frequency 
hopping to form a hybrid time-division, multiple-access (TDMA) spread spectrum system.
* * * * *
 Hybrid Spread Spectrum Systems. Hybrid spread spectrum systems are those which use combinations of two or more types of direct 
sequence, frequency hopping, time hopping and pulsed FM modulation in order to achieve their wide occupied bandwidths.
* * * * *

PART 15--[AMENDED]

 B. Part 15 of Chapter I of Title 47 of the Code of Federal Regulations is amended as follows:
 The authority citation for Part 15 continues to read:

 Authority: Sections 4(i), 7(a), 302, and 303(r) of the Communications Act of 1934, as amended.

 1. New s 15.126 is added to read as follows:

s 15.126 Operation of spread spectrum systems.

 Spread spectrum systems may be operated in the 902-928 MHz, 2400-2483.5 MHz and 5725-5850 MHz frequency bands subject to the 
following conditions:
 (a) They may transmit within these bands with a maximum peak output power of 1 watt.
 (b) RF output power outside these bands over any 100 kHz bandwidth must be 20 dB below that in any 100 kHz bandwidth within the 
band which contains the highest level of the desired power.   The range of frequency measurements shall extend from the lowest 
frequency generated in the device (or 100 MHz whichever is lower) up to a frequency which is 5 times the center frequency of the 



band in which the device is operating.
 *25240 (c) They will be operated on a noninterference basis to any other operations which are authorized the use of these bands 
under other Parts of the Rules.   They must not cause harmful interference to these operations and must accept any interference 
which these systems may cause to their own operations.
 Note.--Spread spectrum systems using the 902-928 MHz, 2400-2500 MHz and 5725- 5850 MHz bands should be cautioned that they are 
sharing these bands on a noninterference basis with systems supporting critical government requirements that have been allocated 
the usage of these bands on a primary basis.   Many of these systems are airborne radiolocation systems that emit a high EIRP which 
can cause harmful interference to other users.   For further information about these systems, write to:  Director, Office of Plans 
and Policy, U.S. Department of Commerce, National Telecommunications and Information Administration, Room 4096, Washington, D.C. 
20230.
 Also, future investigations of the effect of spread spectrum interference to Government operations in the 902-928 MHz band may 
require a future decrease in the power limits.
 (d) For frequency hopping systems, at least 75 hopping frequencies, separated by at least 25 kHz, shall be used, and the average 
time of occupancy on any frequency shall not be greater than four-tenths of one second within a 30- second period.   The maximum 
bandwidth of the hopping channel is 25 kHz.   For direct sequence systems, the 6 dB bandwidth must be at least 500 kHz.
 (e) If the device is to be operated from public utility lines, the potential of the RF signal fed back into the power lines shall 
not exceed 250 microvolts at any frequency between 450 kHz and 30 MHz.

PART 90--[AMENDED]

 C. Part 90 of Chapter I of Title 47 of the Code of Federal Regulations is amended as follows:
 The authority citation for Part 90 continues to read:

 Authority: Sections 4(i), 7(a), 302, and 303(r) of the Communications Act of 1934, as amended.

 1. Section 90.19(g)(3) is revised as follows:

s 90.19 Police radio service.

* * * * *
 (g) * * *
 (3) A licensee may use, without special authorization from the Commission, any mobile service frequency between 40 and 952 MHz, 
listed in Subpart B of this Part of the Rules, for communications in connection with physical surveillance, stakeouts, raids, and 
other such activities.   Such use shall be on a secondary basis to operations of licensees regularly authorized on the assigned 
frequencies.   The maximum output power that may be used for such communications is 2 watts.   Transmitters, operating under this 
provision of the Rules, shall be exempted from the station identification requirements of s 90.425.   Use of Public Safety 
frequencies not listed in paragraph (d) of this section is conditional on the approval of the coordinator corresponding to each 
frequency.   Spread spectrum transmitters may be operated on Public Safety frequencies between 37 and 952 MHz, providing that they 
are type accepted by the Commission under the provisions of ss 2.803 and 90.203 of the Rules, and meet the following conditions:
 (i) Frequency hopping transmitters can be operated, with a maximum output power of 2 watts, on any Public Safety mobile service 
frequency between 37 and 952 MHz listed in Subpart B of this section.   At least 20 hopping frequencies shall be used and the 
average time of occupancy on any frequency shall not be greater than 1/10 second in every 2 seconds;
 (ii) Use of spread spectrum transmitters under this section of the Rules is subject to approval by the applicable frequency 
coordinator of the radio services of the district in which the license and equipment are to be used.
 2. Section 90.207 is amended by revising paragraph (k) as follows:

s 90.207 Types of emissions.

* * * * *
 (k) For stations in the Fire, Police and Power Radio Services utilizing digital voice modulation, in either the scrambled or 
unscrambled mode, F3Y emission will be authorized.   Authorization to use F3Y emission is construed to include the use of F9Y 
emission subject to the provisions of s 90.233.
 3. Section 90.209 is amended by adding new paragraph (h) as follows:

s 90.209 Bandwidth limitations.

* * * * *
 (h) All out of band emissions, including spurious emissions from switching, that are produced by frequency hopping systems, shall 
be kept below the limits specified in this Section of the Rules for similar systems which are modulated about a fixed frequency and 
do not frequency hop.

Appendix C--Initial Coordinator Guidelines for Spread Spectrum

 Spread spectrum can be an important tool for law enforcement use in applications where it is vital that radio transmissions must 
not be detected. While conventional voice privacy systems protect the contents of a message, the presence of encrypted 
communications is readily detectable and in itself could jeopardize the security of a sensitive operation.



 These guidelines are intended to help coordinators in approving requests to use spread spectrum.   Requests that do not comply 
with these guidelines may not be interference-prone, but would require either more detailed calculations or a field test to 
determine the likelihood of interference.   Coordinators may also wish to consider approving uses that have a small interference 
potential if they feel the value of the operation supported exceeds the cost of the interference.
 A frequency hopping (FH) system which hops at a rate of over 100 hops/sec and which hits a conventional voice channel less than 5% 
of the time will not cause harmful interference regardless of field strength.   The interaction of FH with traditional systems 
becomes more noticeable as the hopping rate is decreased. Hopping rates of less than 10 hops/sec are not recommended for this 
reason. Frequency hopping systems may trigger carrier operated repeaters on frequencies that they use. (Such repeaters are rare in 
the public safety services and the Commission has consistently discouraged their use because of their susceptibility to false 
triggering.)   Thus, special steps are needed to protect such repeaters.   Interaction with conventional receivers will be further 
minimized if the hopping frequencies are interleaved between conventional channels.
 The following conditions should be met for coordination without a field test:
 1. All FH systems should hop at more than 10 hops/sec.   As hopping rates greater than 100 hops/sec are preferred, coordinators 
may wish to have a field demonstration of slower systems.
 2. The coordinator should ensure that the sum of the inverse of the processing gain (that is, the number of frequencies used) of 
all FH systems operated in a given band within a 70 mile diameter does not exceed .05.
 3. All frequencies used by carrier operated repeaters within 50 miles should be excluded from the set of hopping frequencies 
unless it can be demonstrated that the turn-on delay of the repeater is adequate to prevent false triggering (50-100 ms is probably 
needed).
 4. All frequencies used by digital data systems and paging systems within 50 miles should be excluded from the set of *25241 
hopping frequencies unless a field test can show absence of harmful interference.

[FR Doc. 85-14590 Filed 6-17-85;  8:45 am]

BILLING CODE 6712-01-M

50 FR 25234-01, 1985 WL 124005 (F.R.)
END OF DOCUMENT