The FCC Changes The Rules on 915 and 2400 MHz Bands
PR Docket No. 93-61:
Adopted on February 3, 1995 and released February 6, 1995, in
Report and Order form, this rulemaking virtually destroys the 915 MHz ISM band as
we know it. In short, the FCC established a new service: the Location and Monitoring
Service (LMS) that encompasses the old Automatic Vehicle Monitoring Service (AVM)
and future advanced transportation related services. The impact of this step by
FCC is significant. The FCC adopted rules for the future licensing and continued
development of a number of services, including Amateur Radio, in the 902 to 928 MHz band.
Radio Amateurs will continue to have access to 902 to 928 MHz, on a secondary
basis to the new LMS systems -- as will industrial, scientific, and medical
(ISM) systems and government users. Unlicensed low power "Part 15"
users are now restricted to a secondary basis to all the above, including amateurs.
The FCC will adopt a plan to afford both amateurs and Part 15 users "a greater
degree of protection to their operations" (from interference from other services).
The FCC also will clarify what constitutes harmful interference to LMS licensees by
Part 15 devices and by amateurs.
The FCC also said it would use a "negative definition" to clearly
establish the parameters under which amateurs and Part 15 users may operate
without risk of being considered sources of interference to services with a
higher allocation status.
Some highlights from the FCC docket follow:
- Multilateration and non-multilateration LMS systems, amateur operations,
and Part 15 devices will all play an important role in providing valuable services
to the American public in the coming years. We believe that our decisions in this
proceeding recognize this importance and will enable all of these services to make
continued use of this spectrum. As detailed in our later discussion, commenters
representing each of these services indicate the need for varying amounts of
spectrum and varying degrees of interference protection from each other's operations
in the band. We have therefore developed a spectrum plan that attempts to
accommodate all of these users' requirements. The plan: 1) continues to permit
secondary operations by unlicensed Part 15 and amateurs across the entire band,
but affords users in these services a greater degree of protection to their
operations: 2) enables non-multilateration LMS systems to operate on spectrum
separate from multilateration systems; and 3) allocates spectrum on an exclusive
basis for multilateration LMS licensees.
- In this Report and Order we have therefore made the following decisions:
- Charge the name of this services from the Automatic Vehicle Monitoring
(AVM) to the Location and Monitoring service (LMS) (see paragraph 1).
- Change the terminology used to refer to the two general categories of
LMS technologies from "wideband" and "narrowban" to
multilateration and "non-multilateration," respectively, (see paragraph 14).
- Permit multilateration LMS systems to locate any object --
animate or inanimate-- ancillary to their primary vehicular location and
monitoring services (see paragraph 24).
- Permit LMS systems to transmit and receive status and instructional informational,
both non-voice and voice, related to the location and monitoring of a mobile unit and
permit LMS systems to interconnect with the Public Switched Network (PSN) on a restricted
basis (see paragraphs 26-27).
- Expand LMS license eligibility to all entities eligible to be licensed under
Part 90 of our Rules and allow services in the 902-928 MHz band to be provided by LMS
licensees to both individuals and the Federal Government on a commercial basis to
paying subscribers (see paragraph 28).
- Clarify what constitutes harmful interference to multilateration licensees by
unlicensed Part 15 devices and amateur operations (see paragraphs 35 - 36).
- Allocate an additional 8 MHz of spectrum in the 902-928 MHz band for LMS use,
permitting the entire band to be used for this purpose. Adopt a spectrum allocation
scheme for the 902-928 MHz band that assigns separate sub-bands for multilateration
and non-multilateration operations as follows:
|Band (MHz) ||System License|
|902.000-904.000 ||Non Multilateration|
|904.000 - 909.750 ||Multilateration|
|909.750 - 919.750 ||Non Multilateration |
|919.750 - 921.750 ||Multilateration and Non Multilateration |
|921.750 -927.250 ||Multilateration|
|927.250 - 928.000 ||Multilateration |
- License exclusive multilateration LMS systems within each Major Trading
Area (MTA) and four additional MTA like service areas in three sub-bands
designated above, and resolve mutually exclusive applications through
competitive bidding (see paragraph 50-57).
- Grandfather base stations of multilateration system licensee authorized
as of February 3, 1995 and constructed and in operation by April 1, 1996
(see paragraphs 61-64).
- License non-multilateration systems on a shared basis in the three
sub-bands designated above (see paragraphs 69-70).
- Allow multilateration licenses to commence operations only after
demonstrating interference with Part 15 operations is minimized (see paragraphs
This proceeding also set new definitions for "interference free" levels
of transmitter power output for both amateurs and Part 15 users. Be careful with
design, installation or operation of any new SS systems in this Band in the future!
ET Docket No. 94-32:
The FCC has now ruled on various proposals for the 2390-2400,
2402-2417 and 4660-4685 MHz frequency bands. The major changes resulting from this
- Adoption of 2390 to 2400 MHz as an additional Part 15 ISM frequency band.
- Elevation of Radio Amateur operations at 2390 to 2400 MHz and 2400 to 2483.5 MHz
to the Primary service.
It seems that the NTIA sponsored moves behind this Docket were only partly successful.
The FCC widened the 2.4 GHz band by 10 MHz, but allowed amateurs primary status over
Part 15 users. We don't think all the battles for this band or some of the higher
frequency bands are over yet! SSS looks forward to continued "haggling" on
frequency assignments at these frequencies -- since the commercial auction value of
telecommunication spectrum is now a proven commodity.
The FCC also has made several changes to Part 15 rules, including adding new sections
covering Unlicensed PCS Devices. Be sure you get an up to date copy of part 15 before
spending any time or money on decsions regarding ISM band equipment or system regulations.
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