Using wireless for one-way streaming of digital audio broadcasting?

For a while I've been thinking about the possibilities of 802.11
(or similar) for one-way streaming of non-licensed digital audio and
possibly even digital video broadcasting. It could be received using a
personal computer with wireless capability and running a special
application, but could also be received and converted to audio by
simple, very inexpensive, portable radio-like (Walkman-like) devices
(such devices would not be PCs -- they'd have an 802.11 receiver and a
simple means to extract the streaming digital broadcast and convert it
to analog for listening the old fashioned way -- processor and other
hardware needs should be quite minimal.)

Why the interest? Well, I've been interested for quite some time with
legal, unlicensed radio broadcasting. It is little known by many that
in the U.S., the FCC allows unlicensed radio stations both in the BCB
(AM: 520 to 1720 kHz) and FM bands. The downside of course is
transmission power, distance and even antenna size, which is severely
limiting, especially for legal FM operation (which is the most
suitable for analog broadcasting.) In fact, unlicensed operation is
allowed in a lot of the rest of the radio spectrum, but is severely
limited power-wise as to make it impractical for even localized radio
broadcast use.

There is a definite need for unlicensed one-way broadcasting with a
usable reception range of at least a mile. It bypasses the commercial
broadcast stations run by corporate conglomerates, allowing for airing
alternative news, views and music, and it would be oriented towards
the needs of the local community without commercial filtering. There
are actually quite a few unlicensed AM and FM stations serving many
communities, despite the technical limitations (they are harried,
though, by commercial broadcasters.) It is also of interest in third
world situations, where very inexpensive radio systems to serve remote
villages are useful, and where using Internet-connected computers is
out-of-the-question.

But unlicensed analog broadcast also has its problems. As just noted,
power and distance. There's also interference issues. And finally that
analog simply sucks in audio quality (some would debate that, but
achieving red book CD audio quality with FM is expensive on both the
transmitter and receiver sides, and it is still analog subject to
interference -- and anyway legal unlicensed FM broadcasting is way too
limited in range, moreso than AM is.) There is the possibility of
digitally broadcasting on the AM and FM bands, but again there are the
legal power and distance limitations, and the digital will require
compression.

So, it is very intriguing to latch onto 802.11 (or similar) technology
for one-way streaming of digital audio broadcasting (greater range,
very small antenna sizes, inexpensive equipment on both ends, full red
book CD quality with no compression needed, etc.) I surmise that it is
legally possible to do this, and that potential reception distances
would be measured in miles (with a good receiving antenna)?

Assuming these to be correct, how would one use 802.11 or similar in
practice? I'm not asking if this makes sense (I believe there is a
need and market as noted above), but whether it is doable, both
technically and legally.

Furthermore, it is important that reception and listening be done
without the need for a PC-level or even PDA-level computer (although
it could be.) I'm thinking of a "portable radio" using earbuds that
costs no more than $10-20 to manufacture. Is this doable? (This brings
up the idea of designing open source circuits and diy kits to build
such "portable radios".) Note that streaming is one-way, so the
"portable radio" would not broadcast back to the transmitter --
likewise the transmitter would only be a transmitter, streaming the
digital audio content.


Am I stupid and clueless (I admit I know little about wireless
technology)? Or are there some possibilities here?

Thanks.

Mark

Mark <(E-Mail Removed)> wrote:
>For a while I've been thinking about the possibilities of 802.11
>(or similar) for one-way streaming of non-licensed digital audio and
>possibly even digital video broadcasting.

>There is a definite need for unlicensed one-way broadcasting with a
>usable reception range of at least a mile.

802.11 doesn't do a mile, maybe a few hundred feet, unless you get
into expensive fixed antennas, and then you are out of the league of
your $10-20 reciever.

> It bypasses the commercial
>broadcast stations run by corporate conglomerates, allowing for airing
>alternative news, views and music, and it would be oriented towards
>the needs of the local community without commercial filtering.

So get a low-power FM license and see how you do. Trying to make a
silk purse (radio/tv broadcast) out of a sow's ear (802.11) isn't
going to bring listeners flocking to hear you...

You could do it, but I'm not sure why you'd bother. Why not do
podcasting or streaming audio/video over the Internet? Then you don't
need to restrict your audience geographically, and could potentially
have a larger audience. [If you want to yack about neighborhood
issues, you can, just tell your neighbors where to listen...]

On Sat, 03 Dec 2005 17:34:12 GMT, Mark <(E-Mail Removed)> wrote:

>There is a definite need for unlicensed one-way broadcasting with a
>usable reception range of at least a mile.

802.11 will not go a mile. It also requires a "connection" to work
which means it has to be a two way system, not just one way. Even UDP
packets require keep alives and management frame ACK's. Of course you
could invent a new protocol that doesn't require ACK and will in a
connectionless environment. That's been done in other services. There
are lots of other problems with 802.11 broadcasting, not the lease of
which is the interference you're certain to create. If you impliment
such an outdoor broadcast scheme in my backyard, I would be first to
contact the FCC WTB EB (enforcement bureau).
http://www.fcc.gov/eb/

Permit me to derail your great idea and offer a replacement. Since
your alleged audience is just dying for your broadcasting content, the
method of delivery need only be cheap and easy. I suggest you look
into DRM (Digital Radio Mondial) digital broadcasting on AM and FM
frequencies. The receiver is nothing more than a butchered FM radio,
with the IF (not audio) output shovelled into the sound card inputs.
There's quite a bit that can be done with a highly compressed digital
audio channel.

http://www.drm.org
Also look under DAB (digial audio broadcasting), IBOC, and Eureka 147.
You can get ready to run products:
http://www.mayah.com/products/drm-2010.htm
or you can build your own:


We had a local meeting where I wanted to be the first all digital
bootleg low power FM station in the country. However, absolutely
nobody else was interested so the idea died. I still want to do it
but I can't do it all myself. So, it's your turn. Carry the banner
of "spectrum efficiency" and "voice of the people" and see if it gets
your fine and sentence reduced.



--
Jeff Liebermann (E-Mail Removed)
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

William P.N. Smith wrote:
> Mark wrote:

>> For a while I've been thinking about the possibilities of 802.11
>> (or similar) for one-way streaming of non-licensed digital audio
>> and possibly even digital video broadcasting.
>
>> There is a definite need for unlicensed one-way broadcasting with a
>> usable reception range of at least a mile.

> 802.11 doesn't do a mile, maybe a few hundred feet, unless you get
> into expensive fixed antennas, and then you are out of the league of
> your $10-20 reciever.

Thanks for your feedback.

1. I did say 802.11 or *similar* (using gigahertz carriers). I am
hoping experts such as yourself can clarify this particular
matter of the various candidate wireless carrier technologies.

2. The broadcast antenna can be optimized by bringing it outside and
raising it to higher ground, etc. (What are the legal power
limits?) It need not be a receiving antenna, only a transmitting
antenna. Why do I keep hearing about 802.11 (or similar) wireless
operating (two-way) over quite long distances such as 30 miles
using pretty cheap antennas? Won't some of that apply here?

3. Who says that *receiving-only* directional antennas need to be
expensive? It seems like they could be built for a few dollars.
They only need to be "receive only". A cheap small dish might be
made out of an old car headlight reflector or something. *laugh*

It seems like a lot of limitations of wireless are due to the need for
it to be two-way with low-packet loss for effective LAN communication.
But I'm not talking about two-way -- I'm talking about one-way, and
this should free up some inherent limitations (but not all of them.)


>> It bypasses the commercial broadcast stations run by corporate
>> conglomerates, allowing for airing alternative news, views and
>> music, and it would be oriented towards the needs of the local
>> community without commercial filtering.

> So get a low-power FM license and see how you do.

This is not acceptable. FCC licensing is not acceptable. Anyway FM is
analog, and am interested only in digital broadcasting which directly
integrates with laptops running wireless, but also allows inexpensive
portable radio reception. I'm not sure if the FCC FM license will even
allow digital broadcasting -- I think not.

Your premise is that the wireless approach will not allow more than
a couple hundred feet of reception distance. For the reasons I give
above, I have not yet been persuaded that this is true. That is, I
believe there is an inexpensive "formula" to get the general concept
to work (in a practical sense) for one mile or more of reception and
maintain red book CD audio quality. One mile would be acceptable, in
my estimation.

After all, the receiver need not communicate back to the transmitter.


> Trying to make a silk purse (radio/tv broadcast) out of a sow's ear
> (802.11) isn't going to bring listeners flocking to hear you...

Well, maybe using the phrase "802.11" is incorrect.

What other wireless carrier technologies could be considered? I've
not hidden the fact that I know next to nothing about wireless
technologies other than being a user of 802.11g (I have a wireless
hotspot and my laptop is wireless enabled.)


> You could do it, but I'm not sure why you'd bother. Why not do
> podcasting or streaming audio/video over the Internet? Then you
> don't need to restrict your audience geographically, and could
> potentially have a larger audience. [If you want to yack about
> neighborhood issues, you can, just tell your neighbors where to
> listen...]

True, but there is definite *third world* and remote applications
for the general system as I envision it, particularly among the poor.
Both the transmitting and receiving portions should be cheap to
implement. Transmitting would probably be done using a very
inexpensive laptop configuration connected to an external antenna
that would probably not be much more than a wire on a tall pole
connected by RG6 (such broadcasting can also simulcast over the
Internet if desired.) Reception can be by wireless laptops and by
(hopefully) the $20 portable radio receiver with earphones. What
usually restricts usage of broadcast in local settings is the cost and
complexity of the transmitting equipment. Plus, with wireless we are
now talking about red book digital audio quality, not limited by
analog (AM or FM) restraints. Heck, the broadcast can originate
halfway around the world, and via the Internet feed to the locally
broadcasting laptop connected to the transmitting antenna.


Anyway, I am not interested in debating whether there's a market for
this or not. You may be right -- no one will be interested. But I
beg to differ knowing the hobbyist and non-licensed broadcast market
plus the third world market. I see some interesting possibilities
among both hobbyists, serious local community broadcasters, and
third world/remote usage. Mainly because a lot of the hardware
(processors, etc.) is already developed for wireless systems, and I
know it is quite inexpensive.

What I'm interested to know are the technical issues of doing this. Am
I making some assumptions about technology which are wholly incorrect
or offbase? Is it doable to jerry-rig 802.11 (or similar) wireless
technology for unlicensed one-way streaming of digital audio, with a
realistic reception distance of one mile with error free performance
(no doubt there'd be error correction built-in to the digital
signal)? And to do so relatively inexpensively? (I acknowledge there
may be need for a directional receiving antenna to get out the full
mile, but as noted above I just can't believe this would be more than
a few dollars in cost.)

Thanks again.

Mark

Jeff Liebermann wrote:
> Mark wrote:

>> There is a definite need for unlicensed one-way broadcasting with a
>> usable reception range of at least a mile.

> 802.11 will not go a mile. It also requires a "connection" to work
> which means it has to be a two way system, not just one way. Even UDP
> packets require keep alives and management frame ACK's. Of course you
> could invent a new protocol that doesn't require ACK and will in a
> connectionless environment. That's been done in other services. There
> are lots of other problems with 802.11 broadcasting, not the lease of
> which is the interference you're certain to create. If you impliment
> such an outdoor broadcast scheme in my backyard, I would be first to
> contact the FCC WTB EB (enforcement bureau).
> http://www.fcc.gov/eb/

Thanks for your reply. It is a good technical overview of some of the
more important issues. This is what I'm seeking. But I won't go down
without some fight to assure the idea is properly technically vetted
as well as looking at "how to make it work". I follow the dictum that
there's a hundred ways by which something can't work, but all it takes
is one way to make it work. I see some interesting opportunities here,
at least in principle, as I'll note at the end.


Regarding 802.11, I only mentioned that since it is well-known. Not
being an expert in this area, I'm not sure what it is called in a
general sense (is 802.11 a particular family of wireless protocols?)

Now, it is the FCC requirements which are of most interest to me. What
does the FCC say about setting up a wireless "hotspot" (which is sort
of what the transmitter would be)? Does the FCC specify that if
interference occurs with a neighbor that it must be shut down even
if it is working within legal limits of transmission power? Does the
FCC, for the frequencies that 802.11 operates (and there are other
wireless protocols as well) also regulate not only the carrier but the
digital signal imposed on the carrier?

And what are the various gigahertz frequencies allocated for wireless
LAN communication?


> Permit me to derail your great idea and offer a replacement. Since
> your alleged audience is just dying for your broadcasting content,
> the method of delivery need only be cheap and easy. I suggest you
> look into DRM (Digital Radio Mondial) digital broadcasting on AM and
> FM frequencies. The receiver is nothing more than a butchered FM
> radio, with the IF (not audio) output shovelled into the sound card
> inputs. There's quite a bit that can be done with a highly
> compressed digital audio channel.

I am familiar with Digital Radio Mondiale, being a shortwave hobbyist
myself.

And I did investigate using it in various ranges up to 30 mHz, but
because of extreme FCC limitations for unlicensed use in the non-BCB
band it just did not appear to be workable. There was one band next
to the CB band that might be a candidate, but would require the FCC
in opening it up. I don't see it working that well in the MW BCB band,
and there's the issues of setting up efficient transmitting antennas
to work in the MW band.


What interests me about wireless is that it operates in the gigahertz
range (I believe) in a portion of the spectrum where the FCC appears
to not be *that* anal about (maybe I'm wrong here.) The very high
frequency makes efficient broadcast antennas very small (e.g. a few
inches) as well as small and efficient reception antennas. No need
for a ground plane antenna like one needs for MW and the longer SW
bands.

And it is already used for digital communication.

And more importantly. It is now implemented in all kinds of consumer
goods (wireless laptops), so taking advantage of the low cost of
the hardware, the installed laptop base, etc., is intriguing.


> We had a local meeting where I wanted to be the first all digital
> bootleg low power FM station in the country. However, absolutely
> nobody else was interested so the idea died. I still want to do it
> but I can't do it all myself. So, it's your turn. Carry the banner
> of "spectrum efficiency" and "voice of the people" and see if it gets
> your fine and sentence reduced.

Well, all I see are wireless hotspots popping up all over which
already seamlessly integrate into laptops. Also I've heard that
two-way wireless LAN communication can go for more than just a couple
hundred feet (saw something on SlashDot), etc., etc. So, it became
intriguing to me that this avenue at least be explored. If the
real-world technical and legal issues make this idea impractical or
impossible, then so be it. But until the various ways of taking
advantage of the wireless technology revolution are examined, I won't
give up that easily.

Thanks again.

Mark

Mark <(E-Mail Removed)> wrote:
>1. I did say 802.11 or *similar* (using gigahertz carriers).

Higher frequencies have _more_ problems going long distances and
generating high powers than lower frequencies.

>2. The broadcast antenna can be optimized by bringing it outside and
> raising it to higher ground, etc.

Yes, it can. However, you still have legal limits on ERP, and it
still won't go through trees, houses, or other obstacles.

>3. Who says that *receiving-only* directional antennas need to be
> expensive? It seems like they could be built for a few dollars.

Why do you think this? Have you priced WiFi gain antennas?

>> So get a low-power FM license and see how you do.
>
>This is not acceptable. FCC licensing is not acceptable.

Why? If there's a market, and a pent-up listening audience, why
should you care if it's licensed?

>Your premise is that the wireless approach will not allow more than
>a couple hundred feet of reception distance. For the reasons I give
>above, I have not yet been persuaded that this is true.

Look at any of the many path loss calculations that have been done in
the newsgroup. You can't get blood out of a stone.

>True, but there is definite *third world* and remote applications
>for the general system as I envision it, particularly among the poor.

Third world poor people can put up low-power FM transmitters at least
as easily as you can.

>inexpensive laptop configuration connected to an external antenna
>that would probably not be much more than a wire on a tall pole
>connected by RG6 (such broadcasting can also simulcast over the
>Internet if desired.)

Again, look at the loss of RG6 at 2.4GHz. Look at the cost of
low-loss coax at GHz frequencies.

But I could well be wrong, build your mousetrap and see if the world
beats a path to your door.

William P.N. Smith wrote:
> Mark wrote:

>> 1. I did say 802.11 or *similar* (using gigahertz carriers).

> Higher frequencies have _more_ problems going long distances and
> generating high powers than lower frequencies.

I'm curious, then. What's the details behind the so-called 30 mile
distance accomplished with wireless (details on Slashdot a while ago.)
Was this due to high-quality directional antennas on both ends? Or
running at some significantly lower frequency? Or what?

What about WiMax?


>> 2. The broadcast antenna can be optimized by bringing it outside
>> and raising it to higher ground, etc.

> Yes, it can. However, you still have legal limits on ERP, and it
> still won't go through trees, houses, or other obstacles.

Well, it must have some penetrative power, otherwise I could not
connect my laptop, with a reasonable signal, to my wireless router
being 80 feet away, going through, at an angle, about 10 feet of dirt,
then through 12 inches of concrete, then two sheetrocked walls. I
suppose there might be some reflection, although at such high
frequencies I'm not sure there is much reflectivity.


>> 3. Who says that *receiving-only* directional antennas need to be
>> expensive? It seems like they could be built for a few dollars.

> Why do you think this? Have you priced WiFi gain antennas?

For reception only, they should be cheaper than a directional antenna
designed for transmitting as well. I'm only interested in the
reception side, at least when thinking of dirt cheap.


>> Your premise is that the wireless approach will not allow more than
>> a couple hundred feet of reception distance. For the reasons I give
>> above, I have not yet been persuaded that this is true.

> Look at any of the many path loss calculations that have been done
> in the newsgroup. You can't get blood out of a stone.

I assume what you mean is loss in air itself?


> Again, look at the loss of RG6 at 2.4GHz. Look at the cost of
> low-loss coax at GHz frequencies.

Yep, agreed. The transmitter circuitry would probably have to be
quite close to the antenna to minimize high frequency losses when
feeding the antenna.


> But I could well be wrong, build your mousetrap and see if the world
> beats a path to your door.

Well, who knows? Maybe someone here might try to experiment with this.
Maybe some more workable variation of the idea. I'm not setup to do
this -- just offering the idea to the world to do or not do with it as
it pleases. For now I just want to understand the various legal and
technical issues, and variations on the theme, before I put it to
rest.

Mark

Mark <(E-Mail Removed)> wrote:
>I'm curious, then. What's the details behind the so-called 30 mile
>distance accomplished with wireless (details on Slashdot a while ago.)

Go back and read the slashdot article. IIRC they used extremely high
gain antennas on both ends (C-band satellite dishes?), lots of
expensive hardware, and a line-of-sight path that doesn't exist
anywhere else.

>> still won't go through trees, houses, or other obstacles.
>
>Well, it must have some penetrative power, otherwise I could not
>connect my laptop, with a reasonable signal, to my wireless router
>being 80 feet away, going through, at an angle, about 10 feet of dirt,
>then through 12 inches of concrete, then two sheetrocked walls. I
>suppose there might be some reflection, although at such high
>frequencies I'm not sure there is much reflectivity.

That 'path' is exclusively reflective. WiFi does not (IME) propagate
through 8" concrete walls.

>> Have you priced WiFi gain antennas?
>
>For reception only, they should be cheaper than a directional antenna
>designed for transmitting as well.

Then you don't know much about RF. Except for power handling (which
is nil in the case of WiFi), rx and tx antennas are the same.

>> Look at any of the many path loss calculations that have been done
>> in the newsgroup. You can't get blood out of a stone.
>
>I assume what you mean is loss in air itself?

No, I mean the power budget calculations Jeff and others have done
here on a nearly daily basis for the last several years. Output power
minus connector losses, minus feedline loss, plus antenna gain minus
free-space loss plus antenna gain minus feedline and connector loss
compared to receiver sensitivity for a given bit-error rate. RTFNG.

On Sat, 03 Dec 2005 19:40:32 GMT, Mark <(E-Mail Removed)> wrote:

>I see some interesting opportunities here,
>at least in principle, as I'll note at the end.

I don't. If the central access point also has internet access,
there's nothing to stop the user from connecting to
http://www.shoutcast.com
http://www.windowsmedia.com
or other sources of free streaming media and getting their
entertainment fix for free.

I don't have time to explain all the legalities and technical
limitations of every possible method of license free communications
available. You can find that all over this newsgroup, the web, in
weblogs, and in books. When you have something concrete, I'll be
happy to analyze, calculate, or otherwise tear apart your proposal
from a technical angle. Please do some reading and come back with
some less general questions.

>Now, it is the FCC requirements which are of most interest to me. What
>does the FCC say about setting up a wireless "hotspot" (which is sort
>of what the transmitter would be)?

The FCC says nothing. The way it works is that the 915MHz, 2.4GHz,
5.7GHz, 24GHz, and 60GHz frequency bands were set asside for use by
"intentional radiators". The FCC rules are in Part 15. For what
you're doing, it's 15.204 and 15.247 that are important. There are no
restrictions as to what you can do with the service as long as you
stay within the emission requirements.
http://www.access.gpo.gov/nara/cfr/w...7cfr15_00.html

On top of Part 15 is IEEE 802.11. This is a series of specifications
as to how these "intentional radiators" are suppose to communicate and
interoperate. 802.11 is NOT the only data protocol in use on these
frequencies. In addition, there are several incompatible modulation
methods (Frequency Hopping, Direct Sequence, OFDM, Bluetooth, HomeRF,
etc) and lots of proprietary high bandwidth systems on the higher
frequencies. You are not required to use 802.11 but you'll find that
the cost of proprietary is rather substantial.
http://standards.ieee.org/getieee802/802.11.html
Anything you build will need to be FCC type certified as well as
approved by whatever foreign Telecom or Ministry you decide to export.

>Does the FCC specify that if
>interference occurs with a neighbor that it must be shut down even
>if it is working within legal limits of transmission power?

No. The FCC does not care about interference on the unlicensed and
un-coordinated frequency bands. Interference is the price of
unlicensed operation.

>Does the
>FCC, for the frequencies that 802.11 operates (and there are other
>wireless protocols as well) also regulate not only the carrier but the
>digital signal imposed on the carrier?

No. The FCC only is only interested in the emission limits (occupied
bandwidth, duty cycle, and xmit power) as well the usual spurious
emissions limits. The FCC does not care what you do to modulate the
signal.

Things change a bit if you get big. If you have over 200 customers,
you gotta report it to the FCC on form 477.
http://www.fcc.gov/broadband/data.html

>And what are the various gigahertz frequencies allocated for wireless
>LAN communication?

Actually, there are a substantial number beyond the common variety.
See FCC 15.245 through 15.255 for specifics. Each band tend to have
seperate emission requirements so don't assume that if something is
acceptable on one band, it will be acceptable on another.

>I am familiar with Digital Radio Mondiale, being a shortwave hobbyist
>myself.

Fine. Then you're aware that DRM and iBiquity requires a per-receiver
license. Great way to kill a new technology.

More:

http://www.novia.net/~sadams/My_Page...tal_AM_FM.html

http://www.novia.net/~sadams/My_Page...Shortwave.html

>I don't see it working that well in the MW BCB band,
>and there's the issues of setting up efficient transmitting antennas
>to work in the MW band.

OK. You have a 3rd world audience, with no hardware, probably no
money, a mythical pressing need for CD quality audio, and you're
getting picky about the quality of the service. I was listening to
some Canadian DRM station (forgot which one) on 18MHz a few nights
ago. It wasn't CD quality, but the stereo sure sounded good.
http://www.baseportal.com/cgi-bin/ba...tx=/drmdx/main
http://www.drm.org/livebroadcast/livebroadcast.php
I guess 3rd world impoverished listeners have more discerning tastes.

>What interests me about wireless is that it operates in the gigahertz
>range (I believe) in a portion of the spectrum where the FCC appears
>to not be *that* anal about (maybe I'm wrong here.)

I would love to unload my frustrations with the FCC EB (enforcement
bureau). Let's just say that they only enforce high profile cases.
Unless you're a very important person, they don't act on complaints.
You can get away with just about anything as long as you don't piss
off anyone important. That will be a serious problem if you start
selling commerical airtime on your broadcasting system. The
broadcasters might consider you a threat and complain to the FCC. That
will surely bring down the wrath of the enforcement bureau.

>The very high
>frequency makes efficient broadcast antennas very small (e.g. a few
>inches) as well as small and efficient reception antennas. No need
>for a ground plane antenna like one needs for MW and the longer SW
>bands.

Yeah, something like that. Methinks maybe reading a few things about
antenna design might be helpful. I've posted how to do fade margin
and link calculations at least a dozen times in this newsgroup. The
method is the same no matter what technology or frequency you're
using.

>And it is already used for digital communication.

That's the problem. You won't find any two way land mobile users in
the middle of the frequencies used by broadcasters. That's because
the services are incompatible. The same applies to what you're
proposing. In my never humble opinion, broadcasting on 2.4GHz is no
better than jamming existing users.

>And more importantly. It is now implemented in all kinds of consumer
>goods (wireless laptops), so taking advantage of the low cost of
>the hardware, the installed laptop base, etc., is intriguing.

So, you're going to buy me an affordable laptop for Hannukah? Somehow,
my budget just can't seem to catch up with the current definition of
affordable. I do have about 15 different laptops but they're all
junk.

>Well, all I see are wireless hotspots popping up all over which
>already seamlessly integrate into laptops.

The surest sign of success is pollution and abuse. Your idea is very
close to becoming a sign of success.

>Also I've heard that
>two-way wireless LAN communication can go for more than just a couple
>hundred feet (saw something on SlashDot), etc., etc.

Basic lecture on dB's.
3dB is about 0.7 times the range and 2x the coverage area.
6dB is about 2 times the range and 4x the coverage area.
12dB is about 4 times the range and 16x the coverage area.
Bigger antennas mean more coverage and range. There are legal limits
to what can be done. It's not all that simple because there are
different rules for point to point and point to multipoint. See FCC
15.247 or various interpretations online.

>So, it became
>intriguing to me that this avenue at least be explored. If the
>real-world technical and legal issues make this idea impractical or
>impossible, then so be it. But until the various ways of taking
>advantage of the wireless technology revolution are examined, I won't
>give up that easily.

You ask some very good questions. However, they're all the wrong
questions. What you should be asking is how *YOU* will make money
from this service. There are plenty of ideas out there that can make
money for others, or where you can only operate as a free service.
Selling to a 3rd world market is something I can see you have never
even investigated. I know of a few 3rd world communications horror
stories. Let me know if you wanna hear them.


--
Jeff Liebermann (E-Mail Removed)
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

> Well, who knows? Maybe someone here might try to experiment with this.
> Maybe some more workable variation of the idea. I'm not setup to do
> this -- just offering the idea to the world to do or not do with it as

Why? This is sort of like wanting to 802.11 protocols to move video
from one room to another.

Instead, you can just buy a box called a video sender that does this.
It works out of the box, requires no software and is far cheaper than
walking around with a laptop.

Why use something for a mispurpose that will be hard to get going when
there's something out there already that does what you want:-

a) Local FM transmitter
b) Internet broadcasting

David.