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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 <[email protected]>
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 ---
--- [email protected] * Fort Collins, Colorado ---
--- [email protected] * (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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