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Wireless Cable TV FAQ

What it is, how it works, and what companies you should be aware of.
Archive-name: wireless-cable
Last-modified: Sun, April 16, 1995

*** Wireless Cable Television - Frequently Asked Questions (FAQ) ***

Internal Revision: 485

Compiled by Brian J. Catlin <catlin@CS.ColoState.EDU>

A fully html version of this FAQ is available at:
http://www.CS.ColoState.EDU/~catlin/wireless-cable.html


Copyright
---------

This file is Copyright (C) 1993, 1994, 1995 by Brian J. Catlin.  All
rights reserved.  Redistribution of this file in both electronic and
printed form, is permitted provided that this file is distributed in
its entirety, including this copyright notice.  If you redistribute
this file, please let me know so that I can keep track of where this
file goes.


Sources
-------

Most of this information is taken from FCC Public Notices along with
information sent to me by both the FCC and the Wireless Cable
Association (WCA).  Other information has come from numerous
newspapers, magazines, and from discussions with MMDS subscribers.
Items marked with three plus signs (+++) have been added or changed
since the last posting.

I would like to thank Alan Larson, Craig Strachman, David Newman,
David Simmons, and JBlitzEsq for their numerous contributions and
corrections.


Contents:
---------

 +++1.0  Abbreviations used
    2.0  What is wireless cable?
    2.1  What is CellularVision?
    3.0  What are the benefits of wireless cable to the customer?
    3.1  How does wireless cable work?
    3.2  What is the history of MMDS?
    3.3  How does MMDS work commercially?
 +++4.0  What frequencies are used?
    4.1  How many channels can be transmitted?
    4.2  What channels can be sent?
    5.0  What is the range of wireless cable?
    5.1  Does weather affect reception?
    6.0  What equipment is in the subscriber's home?
    6.1  Is wireless cable equipment reliable?
 +++7.0  What about copyright issues?
    8.0  What about security?
 +++9.0  How are wireless cable systems regulated?
    10.0  I saw one of those 'infomercials' about wireless cable.  Are
          these companies legit?
    10.1  How can I tell if a company is running a scam on me?
    11.0  Is there an industry association?
    11.1  Who do I contact for more information?
    11.2  Are there any FTP or gopher sites available for more
          information?
 +++11.3  Wireless Cable people on the net.
    12.0  Where can I get the latest copy of this FAQ?


Questions and Answers
---------------------

1.0)  ABBREVIATIONS USED:

    ITFS - Instructional Television Fixed Service.  Channels that must
           have a minimum of 5 hours per week of educational
           programming.  May be leased for wireless cable usage.
    LMDS - Local Multipoint Distribution Service.  Two sets of 50
           channels in the 28 GHz band.  Not yet available for
           wireless cable usage.
    MDS  - Multipoint Distribution Service.  Two channels that are
           similar to MMDS.  May be used in a wireless cable system.
    MMDS - Multichannel Multipoint Distribution Service.  Two sets of
           four channels each.  Also, type of service known as
           "Wireless Cable".

2.0)  WHAT IS WIRELESS CABLE?

    Wireless cable is a name given to a service that is called
    Multichannel Multipoint Distribution Service (or MMDS).  It is a
    type of cable television system that offers its subscribers a mix
    of satellite channels by transmitting the programming over MMDS
    frequencies along with MDS, OFS, and ITFS frequencies, if they are
    available.  Wireless cable uses Super High Frequency ("SHF")
    channels to transmit satellite cable programming over-the-air
    instead of through overhead or underground wires.

2.1)  WHAT IS CELLULARVISION?

    CellularVision/Suite12 is a company that has been granted special
    permission by the FCC to transmit video services on a higher
    frequency than what wireless cable uses.  They have been testing
    in the 28 GHz (or LMDS) band.  It is believed that the FCC may
    allocate two sets of 50 channels in this band for wireless cable
    type service.

    CellularVision is hoping to provide television plus much more.
    Since the signal is interleaved, it is possible for a large number
    of services to occupy a narrow bandwidth.  CellularVision is
    planning on offering interactive networking, grocery ordering,
    bank transactions, and video teleconferencing.  I am not sure what
    all CellularVision is planning on offering during this initial
    testing period.

    However, using the 28 GHz band means sacrificing signal range.
    These signals aren't able to achieve even the 25-30 mile range
    that MMDS and other 2 GHz services are able to get, given the same
    transmitting power.  To get around this, they are using 35 "cell
    sites" to transmit the programming.  They hope to offer service to
    over 6.3 million subscribers in the region around New York City by
    1995.

3.0)  WHAT ARE THE BENEFITS OF WIRELESS CABLE TO THE CUSTOMER?

    Availability:  Wireless Cable can be made available in areas of
    scattered population and other areas where it is too expensive to
    build a traditional cable station.

    Affordability:  Due to the lower costs of building a Wireless
    Cable Station, savings can be passed on to the subscribers.

3.1)  HOW DOES IT WORK?

    Scrambled satellite cable programming is received at a central
    location where it is processed and fed into special transmitters.
    The SHF transmitters distribute the programming throughout the
    coverage area.  The signals are received by special antennas
    installed on subscribers' roofs, combined with the existing VHF
    and UHF channels from the subscriber's existing antenna, and
    distributed within the home or building through coaxial cable into
    a channel program selector located near the television set.

    Notice that you must provide a UHF and/or VHF antenna if you want
    the broadcast channels.  This is because the Wireless Cable Box
    only provides a UHF/VHF tuner.  Of course, not all boxes include
    even this feature (but most do).

3.2)  WHAT IS THE HISTORY OF MMDS?

    It is a fairly new service that developed from MDS (multi-point
    distribution service) which could only send one or two channels.
    Originally, the FCC thought MDS would be used primarily to send
    business data.  However, since MDS's creation in the early 70's,
    the service has become increasingly popular in sending
    entertainment programming.  Because the FCC does not regulate the
    content of the transmission, alternative uses would not be
    prohibited.

    Today, there are systems in use all around the U.S. and in many
    other countries including the former Soviet Union, and Canada.
    Other systems are being built all over the place, including
    Australia.  At the rate that the FCC has been receiving
    applications, it looks as if many more systems are going to be
    built in the U.S..

3.3)  HOW DOES MMDS WORK COMMERCIALLY?

    A MMDS licensee, which is similar to a broadcast station owner,
    leases transmission time to programmers on a first-come, first-
    served basis.  The programmers, in turn, are responsible for
    designing and selling their programs to the subscriber.

    A MMDS applicant can choose to operate as a common carrier.  In
    the telecommunications industry, a common carrier also may provide
    services such as audio only transmissions, telephone, or data.

    A MMDS applicant can alternatively choose to operate as a non-
    common carrier.  This scenario in effect would constitute a non-
    common carrier wireless cable system.

    Also, note that a MMDS license only entitles you to FOUR channels.
    In order to use all 33 channels, you must apply for several
    different licenses.  This can be very costly!

4.0)  WHAT FREQUENCIES ARE USED?

    Frequency                num. of     type of    channel
    Range                    channels    service    groups
    ---------------------    --------    -------    ------------------
    2,150 - 2,162 MHz            2          MDS      1,2,2(A)
    2,500 - 2,596 MHz           16         ITFS      ABC&D
    2,596 - 2,644 MHz            8         MMDS      E&F
    2,644 - 2,686 MHz            4         ITFS      G
 +++  "   -   "                  3         MMDS      H
    2,686 - 2,689.875 MHz       31*        MMDS      Response Channels

    * - Each channel's bandwidth is 125 KHz, and does not carry video.

    There are also tests being made in New York for transmitting in
    the 28 GHz band (LMDS).  The frequencies used are 27.5 GHz - 29.5
    GHz.  I am not sure of how these frequencies are divided between
    the different services.

    The FCC is currently thinking about opening up more frequencies so
    that up to 7 wireless cable companies can compete in the larger
    markets.

4.1)  HOW MANY CHANNELS CAN BE TRANSMITTED?

    When fully implemented, wireless cable operations may have as many
    as 33 channels of broadcast and cable programming.  This, of
    course, depends on which channels are already used in your area.
    Furthermore, 20 of the 33 channels are borrowed from ITFS services
    and are earmarked for educational use.  This means there is a
    requirement to program 20 hours per week per channel of
    educational material.  All educational programming is now allowed
    to be placed on one ITFS channel instead of having it spread over
    the four channels in the ITFS group.  For new ITFS licenses, only
    12 hours per week per channel is required, but they cannot be
    grouped together.  If any of these channels are being used, then
    any extra time can be leased by the MMDS station, if the owner of
    the license agrees.

    Approximately 150 to 300 channels may become available if digital
    compression is used.  There are a few sites that are testing this
    new technology, and I have heard that the video and audio signals
    are quite good.  They are using Zenith's new 16-level digital
    transmission system which is also capable of delivering HDTV (High
    Definition Television).

    Also, since the signals will be sent digitally, it is expected
    that the range of the signal will increase by approximately 3
    times.

4.2)  WHAT CHANNELS CAN BE SENT?

    Wireless cable systems can carry any of the typical cable
    channels.  In the past, some channels refused to let wireless
    cable systems carry their signals.  However, the cable
    re-regulation bill made channels that are available to cable
    companies also available to wireless cable.  It can also send the
    'SuperGuide' data along with similar data services.

5.0)  WHAT IS THE RANGE OF WIRELESS CABLE?

    Wireless cable systems optimally can get a range of up to 25-30
    miles. This depends largely on the terrain, transmitting power,
    both the transmitting and receiving equipment, and many other
    factors.  In order to receive the signal, the transmitting and
    receiving antennas must be line-of-site.

    Because of its low startup costs, and the ability to reach places
    that cannot be served by traditional cable, MMDS may be feasible
    in certain rural areas.

    A range of 75 to 90 miles could be accomplished if a new digital
    compression system is used.  (See question 4.1)

5.1)  DOES WEATHER AFFECT RECEPTION?

    The answer to this question depends on the type of system used.
    For systems that transmit their programming without modification
    (ie. No compression or scrambling), severe fog and/or rain can
    cause the signal to be reflected, causeing the picture to
    deteriorate.  From what I have heard,you can usually expect
    between eight to ten days per year of interrupted service.  This
    figure, I believe, is the average for the current systems
    operating in the U.S..

    If the programming is scrambled, the downconverter/descrambler may
    loose authorization sooner.

    On the other hand, if the programming is sent digitally, or is
    digitally compressed, the signal can deteriorate to a much lower
    level before the picture is affected.  However, once the signal
    gets this weak, the picture will deteriorate at a much faster rate
    as the weather gets worse.  From what I have read, the average
    number of days that this type of service would be interrupted,
    would be one day per year. (This sounds rather optimistic to me...
    does anyone have any info about this?)

    Also, the farther the receiver is from the transmitter, the sooner
    the picture will be affected.

6.0)  WHAT EQUIPMENT IS IN THE SUBSCRIBER'S HOME?

    Each household subscribing to the service has a small antenna on
    its roof (about the size of an open newspaper) and a downconverter
    inside. The downconverter usually includes an addressable decoder
    and a VHF/UHF tuner built in.  This gives it the ability to tune
    in broadcast channels without having to use up valuable MMDS
    channels.  It also allows pay-per-view services and simplifies
    channel blocking and premium channel activation/deactivation.

    Also, the subscriber will need a UHF and/or VHF antenna if they
    want to receive broadcast channels.

    Recently, a new converter has been introduced that will send all
    channels out of the converter at once.  This means that you can
    use your TV's and your VCR's built in tuner instead of having to
    have seperate boxes for each.  This new technology is (hopefully)
    going to be integrated into Wireless Cable converters as well as
    the traditional cable boxes.

6.1)  IS WIRELESS CABLE EQUIPMENT RELIABLE?

    Several excellent manufacturers produce antennas and
    downconverters for signal reception along with decoder boxes.

    Because the signal is broadcast over the air, it is not subject to
    the failures of traditional cable.  However, the receiving end is
    somewhat more complex than most wired cable systems would use.
    Also, the signal is in a frequency range that may be attenuated by
    water (such as rain) and can be blocked by trees.  There is also
    some risk of interference from microwave ovens operating in the
    area on 2,450 MHz.

    There are several companies that provide equipment and consulting
    services.  If you are interested in this, you may want to pick up
    the latest copy of The Broadcasting Yearbook or Multichannel News.
    These can be found at most large libraries.

7.0)  WHAT ABOUT COPYRIGHT ISSUES?

    In the past, wireless cable systems have assumed that they may use
    a compulsory license to pay for copyright issues (similar to what
    cable companies do today).  A compulsory license enables systems
    to re-transmit broadcast signals for a pre-established fee to
    compensate producers of TV programs.  The copyright office
    then announced that wireless cable is NOT a cable system, therefore,
    these systems may not use compulsory licenses.

 +++However, the Satellite Home Viewer Act of 1994 was passed and
 +++enacted on October 18, 1994.  This act establishes that wireless
 +++cable systems fully qualify for the compulsory copyright license in
 +++the same manner as cable systems.  (I would like to thank JBlitzEsq
 +++for this information.)

8.0)  WHAT ABOUT SECURITY?

    In systems that use scrambling, signal security is provided by
    encoding each channel and equipping the converter with a decoding
    device that responds to a pilot signal carrying a data stream with
    authorization instructions.  Thus, the system is totally
    addressable.  No (legal) converter box will have any utility
    unless it is authorized for service by the central computer.  All
    channels, both Basic and Premium, are hard scrambled.  Because the
    wireless cable system is addressable, it can also accommodate pay-
    per-view service.

    One way to defeat this is to use an illegal converter box.  These
    are not as easy to find as the ones for regular cable systems.
    However, a "Universal Descrambler" will probably be able to
    descramble the channels.  (I have not tried this).

    If digital compression is used, then no scrambling is needed as a
    compressed signal is impossible to watch.

    According to Barry Nadler of the FCC office in Vero Beach, "There
    is not any restrictions on receiving wireless cable transmissions.
    There are currently restrictions on the cellular frequencies only.
    If you decode scrambled signals, you are breaking the law.  Cable
    companies can take you to court (Title 47 Section 705) for 'Use of
    information not specifically directed to you'."  This means that
    you may view any unscrambled/unmodified signals with your own
    receiver.  You may not, however, unscramble a signal without
    authorization.  I would like to thank David Simmons for providing
    this quote to me.

9.0)  HOW ARE WIRELESS CABLE SYSTEMS REGULATED?

    The FCC has specifically preempted local regulation of wireless
    cable frequencies, asserting that it is interstate commerce.
    There is no basis for local regulation of the wireless signal.
    Unlike cable, no public rights of way are used, and all
    transmission and reception equipment is on private property.

    Furthermore, the antennas are so similar to regular television
    antennas that there can be no basis for zoning restrictions.  If a
    particular area does have zoning restrictions against antennas,
    they can be fought against in court (the newsgroup
    rec.video.satellite occasionally has these discussions).  However,
    if you signed an agreement that restricted antennas, you may be
    out of luck.

    If you find yourself in this situation, look at the "USENET
    Satellite FAQ List" posted in rec.video.satellite by Gary
    Bourgois.  Most of the information he provides about zoning
    restrictions applies to Wireless Cable antennas as well as TVRO
    (satellite) antennas.

 +++This does not mean, however, that there is little regulation.  The
 +++federal government regulates the industry heavily.  This is done
 +++through processes of getting licenses, transfering licenses,
 +++applying for ITFS channels, report filings, etc.

10.0)  I SAW ONE OF THOSE 'INFOMERCIALS' ABOUT WIRELESS CABLE.  ARE
       THESE COMPANIES LEGIT?

    While some companies may be legit, there are some things that they
    don't disclose.  Because of this, two companies have had temporary
    restraining orders placed against them.  A judge has placed some
    of the following restrictions on them.

      * They may no longer state that applicants are "virtually
        guaranteed" of winning a license in the FCC lottery or that
        most wireless cable licenses are "highly valuable."

      * "There may be substantial delays in the awarding of any MMDS
        license due to the length of time the FCC takes to process
        MMDS applications and award MMDS licenses."

      * That financing for wireless cable systems is hard to get,
        "given the relatively new nature of this field of technology
        and that such financing may require additional funds of the
        customer's own money as a condition" to obtaining a system.

      * Provide a new "Risk Disclosure" statement that applicants must
        sign before sale is completed. This statement informs
        applicants, among other items, that any representations of
        value of systems are opinions and not actual values, that the
        winner of a MMDS lottery wins only 4 channels and that there
        may be competition with satellite, VCR, and other media.

    Temporary Restraining Orders have been placed on, or have been
    filed against: 1) Applied Telemedia Engineering and Management
    (A-TEAM) and 2) Applied Cable Technologies (ACT).  If you deal
    with any type of application preparation firm, be very careful and
    read EVERYTHING.

    Other companies that MAY be questionable include Communications
    Engineering Management Services (CEMS), Decaxo Capital, Techno
    Source, and Western Wireless.  These companies have management
    that were involved in a company selling cellular licenses.  This
    company was forced out of business by the FCC for misleading
    customers.

    Other questionable companies include: MMDS Technologies (also
    known as Metro Communications Group), Tele-Wave Technology, GMT
    Group (also known as National Micro Vision Systems), Continental
    Wireless Cable Television, Spectrum Resources Group, UEG L.C.,
    United Resource Group L.C., United Communications Ltd, Application
    Resolution Trust (ART), Foster City Financial Inc., Michael Charles
    Fisher, Marrco Communications, The Communications Group Inc.,
    Wireless Cable Financial Consultants, B.R. Cable Corporation and
    Communications Corporation, Micro-Lite Television Inc., MCC Ventures
    Group and Monarch Capital Group, Emerging Technologies Group Inc.,
    Microtech Communications Inc., Communications Development
    Corporation, Parkersburg Wireless Ltd., Key West Wireless Partners,
    Lancaster Broadcasting Partners, Transamerica Wireless Systems,
    Shreveport Wireless Cable TV Partnership, Microwave Cable TV
    Partnership, Knoxville LLc, Wireless Solutions Inc., Comcoa Ltd.,
    Vision Communications, Mitchell Communications, Metropolitan
    Communications Corp.

    MMDS Technologies (aka. Metro Communications Group) had a
    restraining order placed against them, but it was later removed.

    American Microtel (also affiliated with Stork and Codima) has
    reached a settlement pertaining to a restraining order that was
    placed against them.

    Also, take note that in the U.S., it is ILLEGAL to enter into (or
    even plan on entering into) a settlement group when applying for a
    license.

    Investigations by both federal and state agencies are continuing
    on many companies.  As I receive info, it will be placed here.

10.1  HOW CAN I TELL IF A COMPANY IS RUNNING A SCAM ON ME?

    Many scams work the following way:

      * Television, radio, and newspaper ads say that a wireless cable
        company is looking for investors to apply for licenses for a
        given area, which the company will service.

      * Investors are asked to pay a large sum of money for
        application and engineering fees.  The application fee is only
        about $155 for four channels.

      * The company then does an engineering study, which may not meet
        the technical requirements, and submits many applications at
        one time to the FCC for that market.

      * If the investor wins a license, the company may not have the
        funding to actually bring a system on-line.

    Most legitimate companies get their investments from institutions
    instead of from individuals.  Also, beware of any "limited liability
    partnerships" as they are frequently scams.

11.0)  IS THERE AN INDUSTRY ASSOCIATION?

    Wireless cable operators, license holders, and equipment/service
    suppliers have formed the Wireless Cable Association.  Among its
    activities the WCA has established a set of industry standards,
    both business and technical.  The WCA has also made the industry's
    concerns known on Capitol Hill and at Federal agencies such as the
    FCC, NTIA, OTA and DOJ.  The WCA has also opened channels of
    communication with organizations such as the National League of
    Cities, NATOA, MPAA and the Association of State Attorneys
    General.

11.1)  WHO DO I CONTACT FOR MORE INFORMATION?

    FCC
    Mass Media Bureau
    Washington, DC  20554

    Wireless Cable Association International, Inc.
    1155 Connecticut Avenue, N.W. Suite 700
    Washington, DC  20036
    (202) 452-7823
    FAX: (202) 452-0041

11.2)  ARE THERE ANY FTP OR GOPHER SITES AVAILABLE FOR MORE
       INFORMATION?

    The FCC is currently setting up a site (ftp.fcc.gov) for anonymous
    FTP of daily reports, transcripts, and many other things on cable,
    radio, television, telephone, and everything else that the FCC
    deals with.  You should first get the README file which tells how
    the files are stored.

    For more information on anonymous FTP, see your local network
    administrator or your BBS's sysop.

    This service is also available via gopher.  All you need to do is
    gopher to ftp.fcc.gov port 70.

11.3)  +++WIRELESS CABLE PEOPLE ON THE NET.

    Here is a list of people or companies that are involved in this
    industry and who have given me information on how they can be
    reached.

    GHz Equipment Company:
    http://access.net99.net/~ghzequip/index.html

12.0)  WHERE CAN I GET THE LATEST COPY OF THIS FAQ?

    The latest copy of this FAQ can be found via anonymous FTP at
    these sites in North America:

    Site: rtfm.mit.edu
    File: /pub/usenet/rec.video.cable-tv/Wireless_Cable_TV_FAQ

    Site: ftp.uu.net
    File: /usenet/news.answers/wireless-cable

    It can also be found at any site that mirrors the news.answers
    archive.  For more information on anonymous FTP, see your local
    network administrator or your BBS's sysop.

    This FAQ can be found via the World-Wide-Web (WWW) at:

    http://www.cis.ohio-state.edu/hypertext/faq/usenet/wireless-cable/
    faq.html

    or for a better linked version, you can get:

    http://www.CS.ColoState.EDU/~catlin/wireless-cable.html

    Other FAQs can be found at:

    http://www.cis.ohio-state.edu/hypertext/faq/usenet/FAQ-List.html


Disclaimer
----------

I have no affiliation with any type of cable or broadcast system.  I
am definitely not an expert in these areas.  I have tried, to the best
of my ability, to interpret and relay the most accurate and up to date
information.  However, I do not guarantee the accuracy of this
information as some of my sources may be biased or incorrect.

For additions, clarifications, corrections, or if you just have some
questions or comments, please feel free to e-mail me.

B. J. Catlin
------------------------------------------------------------------------------
--- Brian J. Catlin                      * Colorado State University       ---
--- catlin@CS.ColoState.EDU              * Fort Collins, Colorado          ---
--- catlin@vnet.ibm.com                  * (970) 495-2841                  ---
--- International Business Machines/ISSC * Client/Server LAN Response Team ---
------------------------------------------------------------------------------
* The opinions expressed above are mine, not IBM's or ISSC's.




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