Additional Spectrum for the Medical Device Radiocommunication Service, 4252-4271 [2012-1540]

Agencies

• FEDERAL COMMUNICATIONS COMMISSION

[Federal Register Volume 77, Number 18 (Friday, January 27, 2012)]
[Rules and Regulations]
[Pages 4252-4271]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-1540]


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FEDERAL COMMUNICATIONS COMMISSION

47 CFR Parts 2 and 95

[ET Docket No. 09-36; RM-11404; FCC 11-176]


Additional Spectrum for the Medical Device Radiocommunication 
Service

AGENCY: Federal Communications Commission.

ACTION: Final rule.

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SUMMARY: This document expands the Commission's Medical Device 
Radiocommunication (MedRadio) Service rules to permit the use of new 
wideband medical implant devices that employ neuromuscular 
microstimulation techniques to restore sensation, mobility, and other 
functions to paralyzed limbs and organs. These medical devices hold 
enormous promise to advance the state of medical care, lower health 
costs, and improve the quality of life for countless Americans. The 
rules will allow these new types of MedRadio devices to access 24 
megahertz of spectrum in the 413-419 MHz, 426-432 MHz, 438-444 MHz, and 
451-457 MHz bands on a secondary basis.

DATES: Effective February 27, 2012.

ADDRESSES: Federal Communications Commission, 445 12th Street SW., 
Washington, DC 20554.

FOR FURTHER INFORMATION CONTACT: Nicholas Oros, Office of Engineering 
and Technology, 202-418-063, Nicholas.oros@fcc.gov.

SUPPLEMENTARY INFORMATION: This is a summary of the Commission's Report 
and Order, ET Docket No. 09-36; RM 11404, FCC 11-176, adopted November 
30, 2011 and released November 30, 2011. The full text of this document 
is available for inspection and copying during normal business hours in 
the FCC Reference Center (Room CY-A257), 445 12th Street SW., 
Washington, DC 20554. The complete text of this document also may be 
purchased from the Commission's copy contractor, Best

[[Page 4253]]

Copy and Printing, Inc., 445 12th Street SW., Room CY-B402, Washington, 
DC 20554. The full text may also be downloaded at: www.fcc.gov.
    People with disabilities: To request materials in accessible 
formats for people with disabilities (braille, large print, electronic 
files, audio format), send an email to fcc504@fcc.gov or call the 
Consumer & Governmental Affairs Bureau at (202) 418-0530 (voice), (202) 
418-0432 (tty).

Summary of the Report and Order

    1. In this Report and Order (R&O), the Commission expands the 
Medical Device Radiocommunication (MedRadio) Service under part 95 of 
the Commission's rules to permit the use of new wideband medical 
implant devices that employ neuromuscular microstimulation techniques 
to restore sensation, mobility, and other functions to paralyzed limbs 
and organs. These medical devices hold enormous promise to advance the 
state of medical care, lower health costs, and improve the quality of 
life for countless Americans. The rules adopted by the Commission will 
allow these new types of MedRadio devices to access 24 megahertz of 
spectrum in the 413-419 MHz, 426-432 MHz, 438-444 MHz, and 451-457 MHz 
bands on a secondary basis.
    2. The Commission's action is part of a larger effort to recognize 
and facilitate the significant advances in wireless medical 
technologies that are revolutionizing treatment for a wide variety of 
medical conditions and creating new health care models to benefit all 
Americans. Such advances have the potential to significantly improve 
the quality of life and sophistication of therapy for countless 
Americans living with a variety of medical conditions and, in turn, 
could result in lower medical costs and extend the time between 
hospital visits and surgical procedures. The devices that we expect to 
be deployed under the rules we adopt herein hold the promise of safer, 
less invasive, and more effective treatment options than those 
available under current medical practice.
    3. The Wireless Medical Telemetry Service (WMTS) and MedRadio 
services, together with unlicensed medical applications developed and 
operated under our general part 15 rules, have supported countless 
vital therapeutic and diagnostic medical applications. The Commission 
recognizes, however, that the dynamic nature of medical technology 
means that our existing rules may need to evolve to keep pace with the 
newest cutting edge therapies. Thus, the Commission included in the 
MedRadio Proceeding a notice of inquiry seeking information in a 
broader context relating to future spectrum needs for wireless medical 
technologies. On September 5, 2007, the Alfred Mann Foundation for 
Scientific Research (AMF or Alfred Mann) filed a petition for 
rulemaking that serves as the basis of this proceeding.
    4. In its petition, Alfred Mann asked the Commission to designate 
up to 24 megahertz of spectrum in the 413-457 MHz range to support new 
medical micro-power networks (MMNs) consisting of implantable 
neuromuscular microstimulation devices and associated external control 
units. Alfred Mann's petition was based on its research dating to 1989 
on implantable medical devices to treat neurological injuries and 
disorders. Since 2005, AMF has conducted extensive work under the 
authority of an experimental license from the Commission to operate its 
devices in the 400-470 MHz band. Alfred Mann's wideband MMN equipment 
is designed to replace damaged nerve connections by performing 
functional electric stimulation (FES) to activate and monitor nerves 
and muscles in order to restore sensation, mobility, and other 
functions to nonfunctioning limbs and organs.
    5. The work that AMF has done with the Veterans Administration and 
other hospitals under its experimental license has proven the potential 
benefits of MMNs. The Commission strongly believes that widespread MMN 
deployment can foster important advancements in medical care by, 
significantly improving the quality of life for the many Americans 
suffering from spinal cord injuries, traumatic brain injuries, and 
strokes. However, it also recognizes that MMNs represent a new type of 
radio communication which does not readily fit into any of the existing 
spectrum allocations. Because of the significant benefits that MMNs are 
poised to deliver, the Commission has concluded that the public 
interest warrants modifying its rules to allow their use. First, the 
Commission discussed the characteristics of MMN operations and 
concluded that this service is best accommodated by modifying and 
expanding our existing part 95 MedRadio rules. Second, it evaluated the 
frequency allocations necessary to support MMN operations and provide a 
secondary allocation in the 413-419 MHz, 426-432 MHz, 438-444 MHz, and 
451-457 MHz bands for use by MMNs as proposed. This means these devices 
cannot cause interference to and must accept interference from stations 
of a primary service. This restriction ensures that the potential for 
interference--i.e., the only cost that would be imposed on other 
parties--is negligible. Finally, the Commission sets forth the service 
and technical rules that will allow MMNs operating on a secondary basis 
to share these bands with incumbent services.
    7. The Commission's decision to allow MMNs to share spectrum with 
existing services supports the Commission's commitment to promoting 
efficient spectrum use to meet growing demand. In the March 2010 
National Broadband Plan, the Commission underscored the importance of 
expanding opportunities for innovative spectrum access models made 
possible by advanced technologies. The Commission sought to promote the 
development of such technologies through its dynamic spectrum use 
technologies Notice of Inquiry. MMNs, which make use of advanced 
technology such as spectrum sensing, dynamic frequency selection, and 
notching out of interference signals to share spectrum with other 
services, demonstrate one such spectrum access model. These techniques 
will allow MMNs to use available spectrum to provide life-changing 
health benefits without impairing the ability of other licensed users 
in these frequency bands to continue providing service.

Medical Micro-Power Networks (MMNs)

    8. In the NPRM, the Commission sought comments on authorizing MMN 
devices to operate in the 413-457 MHz band as an extension of our 
existing part 95 MedRadio rules. As a part 95 MedRadio service, MMNs 
would qualify for license-by-rule operation pursuant to Section 307(e) 
of the Communications Act (Act). Under this approach, medical devices 
would operate in the band on a shared, non-exclusive basis with respect 
to each other. AMF supports the license-by-rule framework and no one 
objects to this approach or suggests alternative licensing methods.
    9. As discussed in the NPRM, the Commission will authorize MMN 
operations under the existing part 95 MedRadio rules. For MedRadio 
devices, the Commission determined that the license-by-rule approach 
minimized regulatory procedures and would facilitate more expeditious 
deployment of new generations of beneficial wireless medical devices. 
Also, MMNs share many characteristics with devices that operate in the 
existing MedRadio service. The core MedRadio band from 402-405 MHz is 
restricted to communication between an implanted medical device and an 
external

[[Page 4254]]

programmer/controller. This is the same architecture employed for AMF's 
MMNs. As with MedRadio implant devices, the MMN implant devices are 
sophisticated medical devices that are intended to be deployed by or 
under the direction of a duly authorized health care professional. The 
power levels proposed by AMF for MMN devices are on par with the power 
levels used by MedRadio devices. Additionally, both MedRadio devices 
and MMN systems are designed to operate in the 400 MHz frequency range, 
although MMNs require greater bandwidth than is available under the 
existing MedRadio rules. For the reasons provided, the Commission 
believes that the MedRadio license-by-rule framework is the best way to 
structure our MMN rules.
    10. In the NPRM the Commission sought comment on a number of 
definitions that AMF proposed be added to the part 95 MedRadio Service 
rules for devices operating in the 413-457 MHz band. These definitions 
were for a Medical Micropower Network (MMN), MMN control transmitter, 
MMN implant transmitter, and MMN transmitter. The Commission adopted a 
single definition for MMN, as follows:

    Medical Micropower Network (MMN): An ultra-low power wideband 
network consisting of a MedRadio programmer/control transmitter and 
medical implant transmitters, all of which transmit or receive non-
voice data or related device control commands for the purpose of 
facilitating functional electric stimulation, a technique using 
electric currents to activate and monitor nerves and muscles.

This definition tracks AMF's proposal in substance, with some word 
alterations to be consistent with the other MedRadio definitions. It is 
important to make these frequency bands available for medical 
applications such as AMF's MMNs that cannot be accommodated in other 
frequency bands and to avoid use of the band by non-medical devices or 
for non-medical purposes. The definition adopted by the Commission 
accomplishes this goal. Because the existing MedRadio definitions in 
the part 95 rules for MedRadio programmer/control transmitter, Medical 
implant transmitter, and MedRadio transmitter can also describe the 
functions of the MMN control transmitter, MMN implant transmitter, and 
MMN transmitter, respectively, the Commission will not adopt MMN-
specific definitions for these devices.
    11. The Commission declines to adopt the more expansive definitions 
proposed by Sienkiewicz and the Cleveland FES Center or to 
substantially deviate from the framework proposed in the NPRM. It 
recognizes that the existing programmer/control transmitter definition 
does not permit use of implanted programmer/control transmitters or the 
deployment of an MMN that functions without a programmer/control 
transmitter, as Sienkiewicz and the Cleveland FES Center have suggested 
should be permitted for MMNs. The record in this proceeding is largely 
based on AMF's MMN system, which uses an external programmer/control 
transmitter which implements a number of interference mitigation 
techniques to allow the MMN to share spectrum with other services in 
these bands and which has been subject to extensive testing. The 
Commission has no information at this time to determine whether an MMN 
without an external programmer/controller could mitigate the effects of 
interference and successfully coexist in these bands. Other use of 
these frequency bands such as for non-FES medical applications or 
allowing transmission of voice data is speculative at this point. No 
one has provided guidance on what alternative specifications would 
appropriately accommodate other uses while not compromising the 
potential of MMNs. Further modification to the rules may be readily 
sought if and when a need arises.
    12. Based on this definition and the rules the Commission adopts 
under it, the Commission can be sure that all MMNs will be designed 
with sufficient interference mitigation techniques and design elements 
to be able to operate on a secondary basis under the Commission's part 
95 rules. At the same time, and because it wants parties to be able to 
tap the vast potential MMN technologies have to transform lives and 
advance the state of medical care, the Commission rejected those 
comments that would have us bind our rules too tightly to AMF's 
specific equipment design. Because manufacturers may develop new MMN 
devices with different interference mitigation techniques, the 
Commission does not think it is appropriate to require that all MMN 
devices function in an identical fashion to AMF's devices. Future 
systems, may rely on technologies that have an even greater capability 
to reject interference than AMF's current design, and the Commission 
will evaluate individual devices as part of its equipment authorization 
process.
    13. Finally, the Commission sought comments in the NPRM on the 
service and technical rules that would apply to medical devices in the 
413-457 MHz band. The discussion generally followed the framework of 
the MedRadio Service rules with, for example, modified power and 
emission bandwidth requirements to accommodate the proposed MMNs. While 
the Commission did not include a separate appendix of proposed rules, 
the NPRM stated that the Commission was seeking comment on allowing 
additional spectrum to be used under the MedRadio Service in part 95 of 
the Commission's rules, referenced new rules that AMF had proposed in 
its filing, and discussed specific service and technical issues at 
length. For this reason parties have had ample opportunity to provide 
meaningful comments on the proposals, and the Commission rejected 
suggestions to the contrary. Because the Commission is including MMNs 
within the existing framework of the MedRadio Service, it will apply 
the existing MedRadio service and technical regulations to MMNs to the 
extent possible and only amend the rules in part 95, Subparts E and I, 
as necessary to distinguish between MMNs and other MedRadio devices. As 
observed in the NPRM, such an approach ``is desirable as it would 
maintain consistency with rules applicable to wireless medical devices, 
particularly for implanted and related therapeutic devices.''

Frequency Bands

    14. Although the Commission concluded that it is appropriate to 
license MMNs as a MedRadio service, it does not follow that it is 
feasible for MMNs to operate on the existing MedRadio frequencies. This 
is because MMNs are different from existing MedRadio applications in 
important technical and design elements. For example, a typical MMN is 
expected to contain multiple implant devices, which will require the 
transmission of much more data than the MedRadio devices operating 
under the existing rules. Moreover, due to their small size, MMN 
implant devices must be even more energy efficient than typical 
MedRadio implants. This efficiency is achieved by using short 
transmissions, which necessitate the use of much wider bandwidth 
signals than the 300 kHz currently permitted in the existing MedRadio 
bands. This limit was put in place to maximize the number of medical 
devices that can use the 5 megahertz available in the 401-406 MHz band 
and is consistent with the operational needs of existing MedRadio 
applications. By contrast, MMNs are designed to operate with a 5 
megahertz emission bandwidth. Thus, the current MedRadio frequencies 
are insufficient to support MMN operation.
    15. Decision. Consistent with our proposal, the Commission will 
allocate the 24 megahertz of spectrum in four

[[Page 4255]]

segments of the 413-457 MHz band for MMN use on a secondary basis, 
i.e., 413-419 MHz, 426-432 MHz, 438-444 MHz, and 451-457 MHz. As 
described by AMF, the propagation characteristics of the 400 MHz band 
make it particularly well suited to host MMN devices, and the band is 
already used for other MedRadio implanted devices. Further, because 
these four band segments will allow for the wide bandwidth signals 
required to transmit large amounts of data in a short amount of time, 
they will provide the emission bandwidth that MMNs require. As 
explained, the Commission does not believe operation on a secondary 
basis will detrimentally impact the development or deployment of MMNs 
as they are designed to be able to operate on a secondary basis.
    16. The Commission also concluded that allocating four band 
segments for MMN use is necessary to ensure that an MMN has sufficient 
spectrum to operate while avoiding causing interference to or receiving 
interference from primary users in the band. An MMN will occupy only 
one band segment at any given time. By having a variety of authorized 
frequency bands available and employing protocols that will allow MMNs 
to quickly migrate from band to band, an MMN licensee will be able to 
make robust use of the available spectrum and respond to changing 
spectrum conditions. In addition, the four band segments serve a mix of 
Federal and non-Federal use. By permitting MMN use of all four 
segments, the Commission will give MMNs more flexibility to operate in 
differing RF interference environments. Commenters expressed concern 
that heavy band use situations could render a particular frequency band 
unavailable to MMNs for extended periods of time. However, the 
Commission does not believe that such a possibility should 
categorically preclude us from allocating the four proposed frequency 
bands. Similarly, the fact that certain interference mitigation 
techniques might work in some situations but not in others is not a 
reason to prevent MMNs from being authorized to operate in all four 
frequency bands. Even in a worst-case situation, the Commission can 
expect that many patients with MMN implants will still be able to make 
effective use of at least one of the allocated frequency segments.
    17. The Commission will implement this allocation by modifying 
footnote US345 to the Table of Allocations for the MedRadio service to 
add a secondary mobile, except aeronautical mobile, allocation for the 
413-419 MHz, 426-432 MHz, 438-444 MHz, and 451-457 MHz frequency bands 
and renumbering this footnote as US64. This allocation will be in 
addition to the existing allocations in these four frequency bands and 
will be limited to use solely by MedRadio operations. The Commission is 
making this allocation through a footnote rather than a direct entry in 
the Table for consistency with the existing MedRadio allocation and to 
emphasize the limited nature of this allocation.
    18. The Commission will place this footnote in both the Federal 
Table and non-Federal Table for each of these four frequency bands to 
allow use in a variety of settings such as in health care facilities 
operated by the Department of Veterans Affairs or the United States 
military, as well as non-Federal health care facilities. Even though 
this allocation will be both a Federal and non-Federal allocation, the 
Commission does not expect any changes in the primary use of any of 
these frequency bands. The 413-419 MHz band will continue to be used 
primarily for Federal mobile and space research services. The 451-457 
MHz band will continue to be used primarily for non-Federal land mobile 
services. The 426-432 MHz and 438-444 MHz bands will continue to be 
shared by the Federal radiolocation service and the non-Federal Amateur 
service. Because MedRadio use of these bands will be on a secondary 
basis, MedRadio stations will not be allowed to cause interference to 
and must accept interference from primary services sharing the bands. 
Consequently, there is no reason for any changes to the current 
coordination procedures between FCC and NTIA for these frequency bands. 
NTIA will continue to manage the 413-419 MHz band, the FCC will 
continue to manage the 451-457 MHz band, and both agencies will 
continue to share management responsibilities of the 426-432 MHz and 
438-444 MHz bands.
    19. The Commission also notes that the spectrum it is adding to the 
MedRadio Service is allocated to similar services in both the United 
States Table and in all regions of the world in the International 
Table. Thus, the Commission believes that MMN devices designed to be 
compatible with U.S. radiocommunications services will be equally 
compatible with the services found elsewhere in the world. However, it 
is not aware of any other administrations that have made provisions for 
MMNs. Although individuals using MMNs should not encounter 
significantly different electromagnetic environments when traveling 
abroad, the use of MMNs may be restricted in other countries. The 
Commission finds that the benefits promised by MMNs as well as the 
ability for MMNs to coexist with the radiocommunications services 
already allocated internationally in the bands under consideration 
support our decision to adopt the proposed allocation.
    20. The Commission rejected other frequency band suggestions made 
by commenters and find that they would not be suitable for MMN use. It 
rejected suggestions by the National Association for Amateur Radio 
(ARRL), the Land Mobile Communications Council (LMCC), the Enterprise 
Wireless Alliance (EWA), and Motorola that the WMTS bands are more 
appropriate for MMNs. In the MedRadio proceeding, the Commission stated 
that frequencies below 216 MHz and above 470 MHz are ``outside the 
range of spectrum generally considered to be the most suitable for 
propagation of radio signals within the human body.'' Because implanted 
MMN devices must operate with minimal power, efficient propagation of 
signals through the human body is extremely important for their 
operation. The WMTS bands from 608-614 MHz, 1395-1400 MHz, and 1429-
1432 MHz are far above the suitable range for signal propagation in the 
human body. While the use of additional power might overcome the 
decreased propagation of signals in the human body in these bands as 
compared to the 400 MHz band, it appears that it is not practical to 
substantially increase the size of batteries in the MMN implant 
devices. In addition, the 608-614 MHz WMTS band is heavily used in 
medical facilities and could complicate reliable MMN service in such 
close proximity. The Commission therefore concludes that the WMTS bands 
are not a practical alternative for use by MMNs.
    21. The Commission's NPRM envisioned, and AMF has designed, MMNs 
that are capable of operating on a secondary basis in frequency bands 
with existing, established incumbent use. Through the use of harmful 
interference mitigation techniques, operations on multiple frequency 
bands, and pre-established shutdown protocols in the event that no 
frequency bands are available, MMNs will be able to operate 
successfully in the lower 400 MHz band. The Commission is further 
encouraged by the fact that the MMN concept is not just theoretical: 
AMF has engaged in prototype development under an experimental license 
that it has held since January 2005 and in actual evaluation and 
testing in cooperation with Federal stakeholders. AMF notes that it has 
developed prototype programmer/controllers that

[[Page 4256]]

implement these interference mitigation techniques and points out that 
these techniques have been independently tested and shown to be 
effective against a wide range of potential interference signals.
    22. AMF submitted interference analyses, test reports, and 
technical studies that it had commissioned to evaluate MMN use in the 
identified bands. These materials were the product of a process that 
began in August 2009, when AMF and the Joint Spectrum Center (JSC) (a 
field office within the U.S. Defense Spectrum Organization that 
provides spectrum planning and support for U.S. military interests) 
entered into a memorandum of agreement (MOA) for JSC to conduct a 
technical analysis to determine whether MMN devices could co-exist with 
incumbent government systems in the 413-457 MHz band.
    23. Pursuant to the MOA, JSC directed a contractor, ITT, to 
collect, validate, and evaluate technical data regarding MMN devices 
and incumbent government systems. The resulting report (JSC Report) 
contained a theoretical analysis to evaluate the electromagnetic 
compatibility (EMC) of incumbent government system receivers in the 
presence of radiofrequency (RF) emissions from MMN transmitters and the 
EMC of MMN receivers of both the programmer/controller (P/C) and 
implanted microstimulator devices--in the presence of RF emissions from 
incumbent systems. The JSC reviewed the report and approved it for 
publication in October 2010.
    24. The JSC Report concluded that, with respect to the MMN-to-
government system interference potential, (1) ``relatively small 
[required separation distances] result from the low EIRP and duty cycle 
of the MMN transmitters combined with the low antenna heights of the 
MMN,'' and (2) MMN systems ``should be operationally compatible and not 
cause unacceptable interference into [incumbent government] systems 
currently authorized to operate in the 410-450 MHz band.''
    25. In addition, AMF commissioned Aerospace Corporation (the 
operator of a federally funded research and development center and 
provider of comprehensive technical service to national security space 
programs) to conduct laboratory tests to determine whether MMNs could 
successfully operate in the presence of incumbent users. To evaluate 
the performance of the MMN network in the 413-457 MHz band, the 
Aerospace testers conducted a wired simulation of the frequency bands. 
Specifically they tested signals representing Federal mobile radio 
(data and voice), radar (ground and airborne), and the Enhanced 
Position Location Reporting System, as well as non-Federal amateur 
television. The tests specifically targeted four MMN interference 
mitigation techniques: spectral excising of narrowband incumbent 
signals; changing frequency bands without suspending critical 
functions; shutting down in a communication link loss scenario; and 
incumbent signal level sensing to avoid interference. The resulting 
report (Aerospace Report) concluded that the AMF MMN System performs 
according to its specifications and can successfully operate in 
presence of incumbent users.
    26. The JSC Report and Aerospace Report offer detailed evaluations 
of specific interference scenarios involving a broad spectrum of 
incumbent operations backed up by testing with actual equipment. Based 
on these reports, the Commission concluded that the record demonstrates 
that MMNs can operate on a compatible secondary basis with primary 
Federal operations in the 413-419 MHz, 426-432 MHz, and 438-444 MHz 
band segments.
    27. The Commission is also convinced that MMNs can operate on a 
compatible secondary basis with primary non-Federal operations. The 
findings of the JSC Report, which focused on Federal systems, and the 
simulations conducted by AMF and the Aerospace Corporation, which 
looked at a wider variety of high-powered signals, support this 
conclusion. In this regard, non-Federal fixed and land mobile radio 
systems in the 451-457 MHz frequency band use the same technologies as 
Federal fixed and land mobile radio systems in the 420-450 MHz 
frequency band. Moreover, the mitigation techniques that the Aerospace 
Report examined have broad applicability. For example a P/C that 
incorporates ``notching'' techniques could filter out a 100 kHz RPU 
signal from a BAS operator.
    28. The Commission believes that the JSC Report, Aerospace Report, 
and associated materials filed by AMF are responsive to these concerns. 
In addition, because these materials provide extensive technical 
details about the interference mitigation techniques employed by AMF's 
MMN devices, the Commission disagrees with the contention of the 
Engineers for the Integrity of the Broadcast Auxiliary Service Spectrum 
(EIBASS) that AMF has provided insufficient technical details about its 
interference mitigating protocols.
    29. A number of parties claim that incumbent operators could 
receive harmful interference from MMN devices. The Commission 
disagrees. Several factors serve to reduce any risk that MMNs could 
cause harmful interference. First, the JSC Report concluded that the 
MMN systems would not cause unacceptable interference into government 
systems in the 413-419 MHz, 426-432 MHz, and 438-444 MHz bands. Again, 
because the non-Federal land mobile systems in the 451-457 MHz are 
virtually identical to the types of government systems considered in 
the JSC Report, there is no basis for us to expect interference to non-
Federal land mobile systems. Such non-Federal land mobile systems must 
overcome interference caused by the high-powered operations of other 
incumbents in the band. For this reason, they are well equipped to 
tolerate the presence of any signals they might receive from an MMN 
system operating at a much lower power. The Aerospace Report, which 
tested actual prototype MMN devices and concluded that incumbent 
services would not receive significant interference, further bolsters 
our conclusion. The Commission further notes that some commenters have 
rejected the likelihood of interference from MMN devices to their 
services which, like land mobile systems, operate at much higher powers 
than MMNs. Finally, the Commission adopts service rules that will 
require an MMN to switch to another frequency if it appears that there 
is an incumbent operating in close proximity.
    30. The studies commissioned by AMF show that MMNs are able to 
function with a significant amount of interference from incumbent 
operations. As such, the Commission is not persuaded by those comments 
that claim that MMNs are incompatible with incumbent non-Government 
licensees. Incumbent systems that operate in the bands under 
consideration share the same high-powered operational attributes that 
MMNs have been specifically designed to tolerate.
    31. To the extent that objections from commenters focus on the fact 
that a transmitter of a particular service may cause interference when 
operating in close proximity to an MMN device, commenters fail to 
acknowledge that the MMN system design anticipates such a scenario. 
There is no dispute that MMN devices may not be able to function in one 
or more of the four bands at a particular moment because of 
interference. AMF's MMN devices are capable of switching among the four 
different bands and are designed to operate on one band at a time, and 
the Aerospace Report found that this design feature worked as planned. 
Moreover, because MMNs are designed to operate in a variety of bands 
with a diverse set

[[Page 4257]]

of Government and non-Government users, a band that is rarely available 
for use in a particular place or at a specific time may be uncongested 
in other situations. Under this reasoning, the Commission is not 
troubled by EIBASS's claim that the tests submitted by AMF did not 
specifically consider RPU operations, a claim AMF refutes. EIBASS 
states that RPU broadcasts are distinct because they often employ a 
long duty cycle and postulates a scenario where extended RPU operations 
would take place at a health care facility. In such a case, the MMNs 
operating in that place and time would simply not be able to access the 
portion of the MedRadio band that is being used by the RPU operator.
    32. Several parties argue that it would be inappropriate for us to 
permit medical devices--and MMNs in particular--to operate on a 
secondary basis. The Commission disagrees with parties that argue that 
it should never allocate spectrum to medical devices on a secondary 
basis. As a general matter, the Commission takes many factors into 
account in deciding whether a given service should operate with a 
primary or secondary status in a designated frequency band or even 
whether a device should operate on an unlicensed basis under part 15 of 
its rules. Each case is evaluated on its own merits. This is also true 
of our allocations for medical devices. At the present time, the 
Commission's rules allow medical devices to operate on a primary basis, 
on a secondary basis, and on an unlicensed basis. The Commission finds 
in this order that the characteristics of the MMN devices at issue here 
warrant operation on a secondary basis. The MMN devices that will be 
deployed under the rules that it adopted herein will be frequency agile 
and can switch to other frequency bands when interference occurs. Thus, 
the MMN devices will be designed with capabilities that enable them to 
share spectrum with primary services successfully. Rigorous testing has 
shown that MMN devices can perform as intended.
    33. The Commission acknowledges that there may be instances when 
MMN devices cannot operate due to interference on all frequency bands. 
However, it also notes that AMF has accounted for this possibility by 
designing its MMN devices to shut down in a controlled, pre-planned 
manner that is designed to avoid harm to the patient or others if 
interference in all four frequency bands prevents successful reception 
of signals by the MMN system. The Commission rejects the notion that 
the potential for such a shutdown should categorically bar us from 
designating spectrum for MMNs and, thus, deny the benefits associated 
with these devices. The Food and Drug Administration (FDA), as part of 
its independent review process, will take into account these ``graceful 
shutdowns'' when it determines when and how MMN use can be prescribed. 
Further, the Commission will require that MMN devices be authorized 
under the direction of a duly authorized health care professional who 
will inform patients of the risks associated with MMN use, including 
``graceful shutdowns.''
    34. The Commission must balance the cost of allowing MMNs to 
operate on a secondary basis in these bands against the benefits that 
patients could potentially receive from their use. Given the extremely 
low risk of incumbent services suffering interference from MMNs and the 
yet lower risk of a harmful result from any such interference, the 
potential benefits of establishing a secondary allocation and adopting 
rules to allow MMN operation outweigh the slight risk to incumbent 
services. Because of the great potential of MMNs to improve the lives 
of people who suffer from a range of illnesses such as spinal cord 
injuries, traumatic brain injuries, strokes, and various 
neuromusculoskeletal disorders, the Commission recognizes the enormous 
potential benefit of allowing MMNs to become a reality. The benefits of 
making this secondary allocation and adopting rules to facilitate MMN 
operations therefore far exceed any potential costs.
    35. Lastly, the Commission addressed several commenters' 
overarching concerns that new MedRadio applications must remain truly 
secondary--neither interfering with incumbent operations nor creating 
an expectation that MMNs must be protected from the types of 
interference that higher-powered primary uses may legitimately cause. 
The Commission fully intends that MMN devices will operate within the 
constraints of their secondary status, and it does not adopt here any 
limitations on the operations of incumbent primary services in these 
bands for the benefit of MMN operation. Because AMF has designed its 
MMNs to anticipate interference and to operate in a challenging 
spectrum environment, the Commission is confident that they will remain 
secondary in both rule and practice. The Commission also clarified that 
MMNs, the Amateur Radio Service, and the non-Federal radiolocation 
service--all of which operate under a secondary allocation in the 426-
432 MHz and 438-444 MHz bands--will have equal status. Given that MMN 
devices are expected to implement measures to mitigate the effects of 
interference, it is reasonable to expect the MMN devices to tolerate 
some interference from the Amateur Service or to move to another 
frequency band as needed. As ARRL concedes, MMN devices are ``unlikely 
generally'' to cause interference to Amateur Radio communications in 
these bands.

Service and Technical Rules

    36. In the NPRM the Commission asked about the service and 
technical rules that should apply to medical devices in the 413-457 MHz 
band. The discussion generally followed the framework of the existing 
MedRadio Service rules and proposed to modify specific rules, such as 
those pertaining to power and emission bandwidth requirements, to 
accommodate the proposed MMNs. The Commission also noted that the 
service and technical rules discussed in the NPRM were essentially 
consistent with recommendations made in the Alfred Mann petition.
    37. The Commission adopted the overall approach proposed in the 
NPRM. Thus, rather than creating a new rule subpart for MMNs, it will 
only amend the service and technical rules contained in part 95 
subparts E and I of its rules to the extent necessary. The Commission 
also adopted service and technical rules that are based on the research 
undertaken for AMF's MMN devices. This approach offers incumbent 
operators greater certainty as to the types and characteristics of 
MedRadio devices that may be deployed in the band and, because it is 
backed by extensive testing, provides greater certainty that MMNs and 
other new medical technologies will be able to thrive on a secondary 
basis in these frequencies. The Commission is confident that the state 
of medical radiocommunication technology will evolve and improve over 
time, as will mitigation techniques that maximize sharing potential on 
a secondary basis. Further development and testing of future 
generations of MMNs may allow us to adopt service rules that provide 
even greater flexibility while still protecting incumbent services. 
However, the service and technical rules it adopts here are appropriate 
based on the record before us today.
    38. Interference Mitigation. Because MMNs will operate under the 
secondary MedRadio Service, they must be designed to function in the 
presence of signals from other services operating in the same frequency 
bands. The interference analysis, test reports, and technical studies 
that AMF submitted

[[Page 4258]]

have demonstrated that it is possible to build MMNs that are highly 
resistant to interference, and as technology continues to advance, the 
Commission believes it will be possible to build MMN devices that are 
even more capable of functioning in the presence of interference. To 
ensure future flexibility for equipment designers, the Commission will 
not require that MMNs include all of the types of interference 
mitigation techniques that AMF has employed in its MMN devices. 
Instead, the Commission will adopt the general requirement that P/C 
transmitters have the ability to operate in the presence of other users 
in the 413-457 MHz band, and it will incorporate several basic 
interference mitigation provisions into its rules. The Commission 
expects that MMN technology developed in the future will be at least as 
capable of co-existing with other services as the system AMF has 
demonstrated.
    39. Regardless of the interference mitigation techniques employed, 
the Commission expects that there will be instances where MMNs will not 
be able to function in a particular frequency band because of a high 
level of interference from other stations. To provide a greater 
probability that an MMN will continue to function in the presence of 
interference, the Commission adopted the requirement that all MMNs be 
capable of operating in any of the four frequency bands and that they 
be able to switch to another frequency band when the band on which they 
are operating becomes unavailable due to interference. The Commission 
concludes that these requirements will not increase the cost of 
equipment unreasonably or be burdensome for manufacturers to meet. As 
AMF has noted, these four bands are nearly adjacent in frequency and 
thus incorporation of a multi-channel operating capability requires no 
significant change in antenna or transmitter design and ``imposes no 
undue economic burden.'' Only a single transmitter and one antenna are 
necessary to cover these four bands. Components to enable manufacturers 
of MMNs to meet this requirement should be readily available since 
equipment is currently designed to operate across the Federal mobile 
bands between 406.1 MHz and 450 MHz and non-Federal mobile bands 
between 450 MHz and 512 MHz. Thus, the Commission concluded that the 
improved robustness of MMNs that will result from these requirements 
will more than offset the expected minimal cost of implementing them.
    40. The Commission also notes that AMF has proposed several rules 
regarding interference mitigation techniques for MMNs. These suggested 
rules are based on AMF's experience in building and testing MMN 
systems. Because of AMF's expertise in this area and the lack of input 
from other parties on this issue, the Commission is adopting technical 
provisions to add assurance that any MMN technology developed in the 
future will be able to operate successfully in the heavily used 413-457 
MHz frequency range.
    41. To be able to switch to another frequency band when an existing 
band becomes unavailable due to high levels of interference, it will be 
necessary for an MMN to be aware of the potential for interference in 
all four frequency bands. To that end, the Commission adopted the 
requirement suggested by AMF that the programmer/controller (P/C) of an 
MMN monitor all four available frequency bands. For the band in which 
the MMN is operating, the P/C must check at least once a second for 
interference so as to be able to switch frequency bands to avoid 
disabling amounts of interference. Because most of the potential 
interferers in these bands such as land mobile, BAS, and amateur 
stations, typically transmit far longer than one second, a once-a-
second monitoring interval should be sufficient to detect interfering 
signals. The P/C must be capable of determining when either direction 
of the communication link between the P/C and the implanted devices is 
being degraded to the extent that communication is likely to be lost 
for more than 45 milliseconds. The Commission will require the P/C to 
move the MMN to another frequency band upon making this determination. 
It will also require the P/C to monitor the other frequency bands often 
enough such that when it must switch frequency bands it has determined 
which frequency band is available based on monitoring of that band 
during the two second period prior to switching. According to AMF, 
incorporating a requirement to monitor MMN channels prior to executing 
a channel change ``will not materially increase production costs.'' 
This is not surprising considering that radios now operating in these 
bands also have a requirement to monitor channels prior to transmitting 
on them and that the technology and techniques to accomplish spectrum 
monitoring in these bands are well established. Thus, the Commission 
concludes that the benefits of these monitoring requirements far 
outweigh the expected costs to comply.
    42. Because the MMN devices operate with such low power, the 
Commission does not believe that they will cause interference to other 
stations sharing the same frequency bands. However, out of an abundance 
of caution it adopted one additional monitoring requirement to further 
reduce the risk of interference. The Commission will require the P/C to 
switch to another frequency band if during the monitoring of the 
occupied frequency band it determines that there is a received signal 
with power greater than -60 dBm in any 12.5 kHz bandwidth being used by 
the MMN device that persists for at least fifty milliseconds. A 
received signal of this strength is likely to be caused by a station in 
close proximity to the P/C. The Commission is using a measurement 
bandwidth of 12.5 kHz for this determination because this is the signal 
bandwidth used by all Federal land mobile stations. Non-Federal land 
mobile operations are currently undergoing a migration from using 25 
kHz channels to 12.5 kHz channels, and consequently, in the near future 
the majority of licensees will also be limited to signal bandwidths of 
12.5 kHz. The Commission chose this measurement bandwidth based on land 
mobile stations because they are the most numerous stations that will 
share these frequency bands with MMNs. This requirement should prevent 
the unlikely occurrence of interference from an MMN device to another 
service sharing the same frequency band.
    43. There may occasionally be instances when MMNs may not be able 
to function because of high levels of interference in all four 
frequency bands. To account for these infrequent occurrences, the rules 
the Commission adopted will require that all MMN transmitters 
incorporate a programmable means to implement a system shutdown process 
in the event of a communication failure or on command from the P/C. 
Because MMNs are used to provide therapeutic benefits to patients, such 
as providing them with a means to move muscles that they would not 
otherwise be able to move, it is important that the Commission require 
the MMNs to incorporate a means to implement a pre-defined system 
shutdown process. The Commission believes that this requirement offers 
vital benefits to patients and is integral to the success of the MMN 
system design. Because MMNs are sophisticated electronic devices and 
the programming necessary to implement a system shutdown process should 
represent only a portion of the overall design costs, the Commission 
concludes that the benefits of a system shutdown requirement far 
outweigh any associated costs. The Commission will require that this 
shutdown process commence within 45

[[Page 4259]]

milliseconds after loss of the communication link or receipt of the 
shutdown command from the P/C.
    44. Contention Protocol Requirement. In the NPRM, the Commission 
sought comment on a number of questions related to contention 
protocols, such as whether a contention protocol should be applied to 
MMN transmitting devices, what kinds of contention protocols should or 
should not be used, and how a contention protocol might be developed. A 
contention protocol would be aimed at allowing multiple MMN systems to 
share the specified frequency bands without causing interference to 
each other. This approach differs from the interference mitigation 
techniques that AMF's MMN devices employ. These techniques are designed 
to allow the MMNs to function in the presence of interference from 
other services sharing the same frequency bands. Commenters supported 
the idea of MMNs using a contention protocol, but no one specified a 
particular contention protocol that the Commission could adopt.
    45. The Commission appreciates that requiring MMNs to use a common 
contention protocol would enable MMNs to more efficiently share the 
available spectrum. However, as no commenters have suggested a specific 
contention protocol, it cannot adopt a requirement for use of a 
specific contention protocol at this time. The Commission also will not 
require the development of a contention protocol by a particular date. 
Given the novelty of MMN technologies, the Commission is not able to 
predict when entities other than AMF will develop MMNs for use in these 
bands and therefore have no grounds to speculate on how and in what 
timeframe a contention protocol may be developed. The Commission does 
encourage manufacturers of MMN devices to cooperate in the development 
of a contention protocol so that the MMN devices may more effectively 
share the limited available spectrum. If, in the future, parties 
establish a specific contention protocol that they believe should be 
applied to these bands, they are welcome to file a Petition for 
Rulemaking to bring such information to our attention.
    46. In the NPRM, the Commission also sought comment on using the 
listen-before-talk (LBT) approach of the existing MedRadio service 
rules to share spectrum between different MMNs. Under this approach, a 
transmitting device must monitor a frequency band for the presence of 
other MedRadio transmitters before beginning transmissions in that 
frequency band. If a signal with power above a certain threshold is 
detected, the transmitting device is not allowed to transmit in that 
frequency band. The Commission has adopted a similar requirement with a 
high power threshold (-60 dBm in a 12.5 kHz bandwidth) to help guard 
against the unlikely occurrence of interference from MMNs to other 
services sharing the same frequency band. Use of this high threshold 
will not be effective in facilitating MMN-to-MMN sharing because MMNs 
transmit such low power over a wide bandwidth. The Commission will not 
adopt a similar requirement with a lower LBT threshold because it would 
interfere with the functioning of the interference mitigation 
techniques employed by AMF's MMN devices. The MMN devices would not be 
able to determine whether a detected signal with a power above the LBT 
threshold is from another MMN or is a signal from another service 
sharing the same frequency band. Because MMNs should be designed to 
operate in the presence of a certain level of interference from other 
services operating in the same frequency band, not transmitting when 
signals above a lower LBT threshold are present would lead to MMNs not 
making use of the available spectrum effectively.
    47. Permissible Communications and Operator Eligibility. In the 
NPRM, the Commission sought comment on restricting implant devices for 
use by persons only for diagnostic and therapeutic purposes and only to 
the extent that such devices have been provided to a human patient 
under the direction of a duly authorized health care professional. This 
requirement is present in our existing MedRadio rules and is consistent 
with how the Commission expects MMNs to be used. No one has raised an 
objection to this requirement. The Commission will therefore apply this 
restriction for MMNs.
    48. The Commission also sought comment on prohibiting the medical 
implant programmer/controller (P/C) from relaying information to a 
receiver that is not included with a medical implant device. This 
prohibition is included in the existing MedRadio rules. The Commission 
will allow P/Cs in different MMNs to communicate with each other for 
the purposes of coordination of the use of the spectrum resource. This 
differs from our existing MedRadio rules, which prohibit controller-to-
controller communication. The Commission expects that each MMN will use 
a spectrum band for short periods of time as is the case for AMF's 
MMNs. Because of this, multiple MMNs should be able to share a 
frequency band without causing interference to each other. If the P/Cs 
for different MMNs from the same manufacturer are able to communicate 
with each other, they can coordinate their networks' respective 
transmissions to avoid transmitting at the same time in the same 
frequency bands.
    49. While the Commission will allow P/C-to-P/C communications to 
facilitate sharing of the scarce spectrum resource, it will not permit 
P/Cs to communicate with non-implanted devices for other purposes. This 
will prevent the 413-457 MHz spectrum from being used as backhaul to 
move data from an MMN to devices outside the network. This is the rule 
currently in place for MedRadio devices under our existing rules and is 
needed because the 413-457 MHz band remains reserved only for those 
medical applications that cannot be achieved in other spectrum and 
allowing other transmissions would cause undesirable spectrum 
congestion.
    50. The Commission also sought comment in the NPRM on whether 
implant-to-implant communications should be allowed, whether each 
programmer/controller must always control the transmitters implanted in 
a single patient, and whether all implants in a patient must be 
controlled by a single programmer/controller.
    51. The Commission will not permit implant-to-implant 
communications. In making the decision to allow MMNs to use spectrum in 
the 413-457 MHz band, it has been favorably impressed by the 
interference mitigation techniques that AMF has demonstrated in the 
independent test described in the Aerospace Report. The system tested 
relied on a P/C external to the body to schedule the implant 
transmissions in accordance with these mitigation techniques. The 
Commission has no evidence on the record that MMNs can successfully 
mitigate the effects of interference if implants are permitted to 
communicate with each other outside the control of a P/C. As a result, 
the Commission cannot reach the conclusion that such a network would be 
able to function in these bands with the incumbent services.
    52. The Commission will allow multiple MMNs to exist within a 
single patient with each network having its own separate P/C. The 
configuration of the networks for a particular patient should be 
determined by the medical needs of the patient and the limits of 
existing technology. This may require the use of different networks to 
accomplish different functions. On the other hand, the Commission will 
not permit a P/C to control implanted devices in multiple patients. 
Given the power limits of the MMN devices, it

[[Page 4260]]

expects that the P/C will have to be within a few meters of the patient 
at all times. Allowing a single P/C to control implants in more than 
one patient would require the patients to remain in close proximity at 
all times, which does not appear to be practical. No commenter has 
suggested a scenario for which such an accommodation would be useful.
    53. Emission Bandwidth. In the NPRM, the Commission sought comment 
on the maximum emission bandwidth that should be allowed for MMN 
devices. Each of the four segments of the 413-457 MHz band allocated in 
this proceeding for use by MMN devices occupies six megahertz of 
spectrum. Alternatively, it also sought comments on whether a smaller 
maximum emission bandwidth (e.g., three megahertz) might be sufficient 
for MMN purposes and might further improve spectrum use and efficiency.
    54. The Commission adopted a maximum emission bandwidth of six 
megahertz. It sees no reason to limit the emission bandwidth to three 
or five megahertz considering that we are allocating six megahertz 
bands for use by MMNs. This will provide flexibility for future, more 
efficient system design. The Commission notes that the maximum emission 
bandwidth of the MMN signals will also be constrained by the unwanted 
emission limits that it is adopting.
    55. Channelization. In the NPRM, the Commission suggested that one 
approach to channelization would be to adopt rules that do not specify 
any particular channeling plan, thereby following the approach used 
with the existing MedRadio Service. The Commission sought comment on 
whether it should require a specific channel plan.
    56. No parties suggested a channelization plan other than AMF's 
proposal for centering the signals in each of the four bands. Given 
that no parties suggest a channelization plan, the Commission has no 
grounds for adopting one, nor does it see any reason to specify that 
emissions be based around a center frequency in each of the four bands 
as AMF has proposed. Because MMN manufacturers will have to design 
equipment to operate on specific frequencies, the Commission recognizes 
that there would be little or no added equipment design cost if it were 
to specify a particular channel plan or center frequency. Nevertheless, 
the Commission sees no benefit in doing so, as it would limit the 
flexibility available for future system design. Accordingly, the 
Commission will not adopt rules specifying a channelization plan for 
MMN devices.
    57. Transmitter Power. In the NPRM, the Commission sought comment 
on the appropriate transmitted power for MMNs. AMF suggested in its 
petition that each implantable microstimulator could be limited to a 
maximum EIRP of 200 microwatts and each P/C transmitter could be 
limited to a maximum EIRP of 1 milliwatt.
    58. The Commission shall adopt the transmitter power limits in 
AMF's proposed rules with one minor change to reflect the fact that it 
is allowing MMNs to use a six megahertz maximum emission bandwidth 
instead of a five megahertz emission bandwidth as AMF proposed. The 
Commission will limit the maximum EIRP of any MMN transmitter to the 
lesser of 1 mW or (10 log B-7.782) dBm where B is the 20 dB emission 
bandwidth of the transmitted signal in MHz. The Commission believes 
that these devices transmitting at these power limits will not cause 
interference to other services in the 413-457 MHz band. The rules it 
adopted will apply the same transmitter power limits to both implanted 
transmitters and the P/C transmitter. The Commission sees no reason to 
apply a stricter power limit to implanted transmitters considering that 
the signals from these devices will be attenuated by body tissue. For 
this reason an implanted transmitter is even less likely to cause 
interference than a P/C transmitter operating at the same power level. 
The Commission will also not place a limit on the number of devices in 
an MMN network or aggregate the powers of the devices. No one has 
suggested a limit on the number of devices or how the power of multiple 
devices may be aggregated. The Commission notes that because the 
implant devices in an MMN will only transmit under the control of the 
P/C, as a practical matter only one implant device in an MMN would 
transmit at any one time. Consequently, it sees no need to aggregate 
the powers of the multiple devices in the MMN for purposes of 
establishing a transmitter power limit.
    59. Duty Cycle. In the NPRM, the Commission sought comment on the 
appropriate duty cycle requirements for MMNs. In its petition AMF 
stated that ``each implanted microstimulator transmits data for 
approximately 5 microseconds every 11 milliseconds and receives data 
for approximately 6 microseconds every 11 milliseconds (i.e., less than 
0.05 percent transmit duty cycle). For a system with 10 to 20 implanted 
microstimulators, the transmit duty cycle of the MCU is approximately 3 
percent.'' AMF made a similar statement in its comments filed 
subsequent to the NPRM when describing the operation of its prototype 
MMNs, but it did not include a duty cycle specification in the rules it 
concurrently proposed. In a recent ex parte submission, AMF indicated 
that it had reached agreement with the United States Department of 
Defense that a 3 percent maximum duty cycle for P/Cs would be 
appropriate.
    60. The Commission finds that it is important to specify a maximum 
duty cycle for MMNs. Because each P/C will occupy a frequency band for 
a fraction of the time, other MMNs will be able to make use of the 
frequency band during the remainder of the time, thus facilitating 
sharing among multiple MMNs. Specifying a maximum duty cycle will also 
help the MMNs share the frequency bands with pulse radars with short 
duration signals that are present in the 426-432 MHz and 438-444 MHz 
bands. Based on the JSC Report and Aerospace Report, the Commission 
concluded that the record demonstrates that MMNs can operate on a 
compatible secondary basis with primary Federal systems in these bands. 
The JSC Report assumed a P/C duty cycle of 3 percent in conducting the 
analysis that concluded that MMNs would be operationally compatible and 
not cause interference to Federal systems. Because the Commission has 
no information on how the conclusions of the JSC Report would be 
affected if the P/C duty cycle were allowed to rise above 3 percent, 
and in recognition of the concurrence of AMF and the Department of 
Defense that a 3 percent maximum duty cycle is appropriate for MMNs, it 
adopted rules that specify a maximum duty cycle of 3 percent for P/Cs.
    61. Unwanted Emissions. The existing MedRadio rules under part 95 
set limits on unwanted emissions from medical transmitting devices 
operating in the 401-406 MHz band. As delineated therein, these 
provisions include limits on both in-band and out-of-band radiation. 
AMF has proposed emissions limits that are similar to the existing 
MedRadio rules. No parties commented on the unwanted emissions limits. 
The rule the Commission adopted applies these emissions limits to these 
frequency bands. Under this approach, in the first 2.5 megahertz beyond 
any of the frequency bands authorized for MMN operation, the EIRP level 
associated with any unwanted emission must be attenuated within a 1 
megahertz bandwidth by at least 20 dB relative to the maximum EIRP 
level within any 1 megahertz of the fundamental emission. In addition, 
emissions more than 2.5

[[Page 4261]]

megahertz outside of the authorized bandwidth must meet the frequency-
dependent set of electric field strength limits of new Sec.  
95.635(d)(1)(iv) of the rules as set forth in Appendix A of the R&O.
    62. Frequency Stability. In the NPRM, the Commission sought comment 
on whether each MMN transmitter should be required to maintain a 
frequency stability as specified in the current MedRadio rules of +/-
100 ppm of the operating frequency over the range: (1) 25 [deg]C to 45 
[deg]C in the case of MMN implant transmitters; and (2) 0 [deg]C to 55 
[deg]C in the case of MMN programmer/control transmitters. AMF 
suggested extending this existing frequency stability criterion in its 
rulemaking petition. Sienkiewicz argues that a frequency stability 
requirement is unnecessary if there is no channelization scheme and 
that devices from different manufacturers do not need to talk to each 
other (i.e., if there is no common contention protocol). Even if a 
frequency stability criterion is needed, he thinks that the criterion 
can be ten times more relaxed than the suggested standard, but he 
acknowledges that the +/-100 ppm standard is common in off-the-shelf 
oscillators.
    63. The +/-100 ppm frequency stability criterion is the standard 
for MedRadio devices in the current rules and represents good 
engineering practice. As Sienkiewicz acknowledges, oscillators that 
meet this standard are readily available. AMF, which has built 
functioning equipment, believes it is an appropriate standard. The 
Commission agrees and sees no reason to depart from the current 
MedRadio frequency stability criterion. The Commission will apply this 
standard to MMN devices.
    64. Antenna Locations. In the NRPM, the Commission sought comment 
on applying the existing MedRadio requirement that no antenna for a 
control transmitter be configured for permanent outdoor use. No one 
objected to this proposal, and the Commission will retain this rule for 
MMNs. Additionally, ARRL stated that only portable, body-worn MMN 
devices should be permitted and that no fixed antenna is appropriate in 
this frequency range. The rules adopted by the Commission will only 
permit MMNs that contain implanted devices and a programmer/controller 
transmitter to operate in the MedRadio Service in these frequency bands 
and the limited transmit power permitted under our rules will limit the 
programmer/controller to locations on or in close proximity to the 
patient. Because the rules will effectively restrict MMNs to portable 
body-worn devices and preclude the use of fixed antennas, the 
Commission concluded that it is unnecessary for us to adopt a new rule 
containing these restrictions.
    65. RF Safety. In the NPRM, the Commission noted that portab