|
Cellular forums Home > Archive > Cellular CDMA technology > May 2005 > AMPS Upgrade
You are viewing an archived Text-only version of the thread.
To view this thread in it's original format and/or if you want to reply to
this thread please [click here]
|
|
| Tropical Haven 2005-05-19, 11:54 am |
| This is a general question about the status of US networks.
I know that in the past, mobile phones were much more powerful (3 watts)
than they are today (I don't know what the exact amount is, but it's
definitely LESS than 3 watts now).
My question is: when [legacy] networks upgrade from AMPS to whatever
technology the provider has chosen, would that constitute an engineering
"nightmare" as the legacy AMPS network was stretically placed to give
the best coverage given that technology?
Let me know your thoughts on this.
TH
| |
| John Navas 2005-05-19, 11:54 am |
| [POSTED TO alt.cellular.attws - REPLY ON USENET PLEASE]
In <41CB8F8E.9080408@example.net> on Fri, 24 Dec 2004 03:39:52 GMT, Tropical
Haven <user@example.net> wrote:
>This is a general question about the status of US networks.
>
>I know that in the past, mobile phones were much more powerful (3 watts)
>than they are today (I don't know what the exact amount is, but it's
>definitely LESS than 3 watts now).
>
>My question is: when [legacy] networks upgrade from AMPS to whatever
>technology the provider has chosen, would that constitute an engineering
>"nightmare" as the legacy AMPS network was stretically placed to give
>the best coverage given that technology?
No.
--
Best regards, HELP FOR CINGULAR GSM & SONY ERICSSON PHONES:
John Navas <http://navasgrp.home.att.net/#Cingular>
| |
| Carl. 2005-05-19, 11:54 am |
| "Tropical Haven" <user@example.net> wrote in message
news:41CB8F8E.9080408@example.net...
> This is a general question about the status of US networks.
>
> I know that in the past, mobile phones were much more powerful (3 watts)
> than they are today (I don't know what the exact amount is, but it's
> definitely LESS than 3 watts now).
>
> My question is: when [legacy] networks upgrade from AMPS to whatever
> technology the provider has chosen, would that constitute an engineering
> "nightmare" as the legacy AMPS network was stretically placed to give the
> best coverage given that technology?
>
> Let me know your thoughts on this.
Speaking in general about the periods I am familiar with...
Those big "bag phones" had 3-watt ability. Analog handhelds were .6 watts,
and the bag phones had some kind of low-power mode for urban areas. Every
analog tower was not spaced expecting all phones to run at 3 watts before
digital service came along. I assume they had issues to deal with,
especially since digital phones were even lower power, but without getting
all complicated the short of it is that there was no sudden jump from 3
watts to .002 watts.
| |
| Donald Newcomb 2005-05-19, 11:54 am |
|
"John Navas" < spamfilter0@navasgro
up.com> wrote in message
news:%eMyd.14137$_3.157886@typhoon.sonic.net...
> [POSTED TO alt.cellular.attws - REPLY ON USENET PLEASE]
> In <41CB8F8E.9080408@example.net> on Fri, 24 Dec 2004 03:39:52 GMT,
Tropical
> Haven <user@example.net> wrote:
>
> No.
Yes. This is particularly true in the western plains where towers were
spaced as much as 80 km apart and the systems designed for 3-Watt phones
with high-gain roof-top antennas. The problem is not so much the technology
as the move to small handsets, rather than in-car phones. Even though
digital signals are generally more power-efficient than analog, small
handsets just don't have the battery or antenna to reach 40 to 50 km. This
left large coverage gaps between the towers for people with handheld phones.
Now, the story is not all negative. Analog systems only supported one level
of cell. All the digital systems support cell hierarchies. So, digital
systems can have super-cells, mini-cells and pico-cells all operating
together. All the carriers had to do was to add a lot of supplemental
digital-only cells in between the old analog/digital towers. The analog
system just stayed in place with the digital as an overlay.
So, John is not wrong when he answered "No". It was not so much a
"nightmare" as a serious problem. However, these days everyone carries a
cell phone on his belt. Fifteen years ago ('89), some people had cell phones
in their cars. There were a number of "bag phones". Almost no one carried
handhelds, and they were the size of a brick. (I got my first cell phone in
'92.) It's the transition to digital that has allowed the industry to grow
and with that growth, they have added the cell sites necessary to support
the traffic.
--
Donald Newcomb
DRNewcomb (at) attglobal (dot) net
| |
| John Navas 2005-05-19, 11:54 am |
| [POSTED TO alt.cellular.attws - REPLY ON USENET PLEASE]
In <41cc4f62_2@news1.prserv.net> on Fri, 24 Dec 2004 10:00:52 -0600, "Donald
Newcomb" <DRNewcomb@attglobal.NOT.net> wrote:
>"John Navas" < spamfilter0@navasgro
up.com> wrote in message
>news:%eMyd.14137$_3.157886@typhoon.sonic.net...
[color=darkred]
>
>Yes. This is particularly true in the western plains where towers were
>spaced as much as 80 km apart
Such areas are relatively rare and rural -- the great majority of tower
spacing is within the maximum range of both GSM and CDMA.
>and the systems designed for 3-Watt phones
>with high-gain roof-top antennas.
Can you be more specific? I don't know of areas actually designed like that.
>The problem is not so much the technology
>as the move to small handsets, rather than in-car phones. Even though
>digital signals are generally more power-efficient than analog, small
>handsets just don't have the battery or antenna to reach 40 to 50 km. This
>left large coverage gaps between the towers for people with handheld phones.
My Sony Ericsson Z600 has worked well out to at least 30 km (near the normal
35 km range limit for GSM), which is greater than the great majority of tower
spacing.
--
Best regards, HELP FOR CINGULAR GSM & SONY ERICSSON PHONES:
John Navas <http://navasgrp.home.att.net/#Cingular>
| |
| Thomas M. Goethe 2005-05-19, 11:54 am |
| "Donald Newcomb" <DRNewcomb@attglobal.NOT.net> wrote in message
news:41cc4f62_2@news
1.prserv.net...
>
> "John Navas" < spamfilter0@navasgro
up.com> wrote in message
> news:%eMyd.14137$_3.157886@typhoon.sonic.net...
> Tropical
>
> Yes. This is particularly true in the western plains where towers were
> spaced as much as 80 km apart and the systems designed for 3-Watt phones
> with high-gain roof-top antennas. The problem is not so much the
> technology
> as the move to small handsets, rather than in-car phones. Even though
> digital signals are generally more power-efficient than analog, small
> handsets just don't have the battery or antenna to reach 40 to 50 km. This
> left large coverage gaps between the towers for people with handheld
> phones.
>
> Now, the story is not all negative. Analog systems only supported one
> level
> of cell. All the digital systems support cell hierarchies. So, digital
> systems can have super-cells, mini-cells and pico-cells all operating
> together. All the carriers had to do was to add a lot of supplemental
> digital-only cells in between the old analog/digital towers. The analog
> system just stayed in place with the digital as an overlay.
>
> So, John is not wrong when he answered "No". It was not so much a
> "nightmare" as a serious problem. However, these days everyone carries a
> cell phone on his belt. Fifteen years ago ('89), some people had cell
> phones
> in their cars. There were a number of "bag phones". Almost no one carried
> handhelds, and they were the size of a brick. (I got my first cell phone
> in
> '92.) It's the transition to digital that has allowed the industry to
> grow
> and with that growth, they have added the cell sites necessary to support
> the traffic.
>
I had a GE mobile cellular that was 1.5 watts rather than then standard
3 watts. It was a cost leader phone and the dealer cautioned against it due
to lack of power. There were a couple of times in the Tampa, FL area, around
1988 or so, that I couldn't get out while people next to me with 3 watt
phones could. Antennas appeared comparable, Motorola 3 db gain ones with the
NMO mount on the trunklid. On the other hand, I could get out when folks
with the first Motorola and GE handhelds could not.
So yeah, at least some of the original systems were designed just as
Donald says, for 3 watt mobiles with good antenna. Drop below that, and you
could have had trouble. I also remember having to carry (along with the
20-30 lbs of camera gear) the big 3 watt NEC "portables" with a massive
NiCad battery pack. It didn't even reside in a bag, it was a hard metal box
with hard metal encased batteries.
Since the future was clearly handheld, the carriers kept enhancing their
systems to provide coverage.
--
Thomas M. Goethe
| |
| Tropical Haven 2005-05-19, 11:54 am |
|
John Navas wrote:
> [POSTED TO alt.cellular.attws - REPLY ON USENET PLEASE]
>
> In <41cc4f62_2@news1.prserv.net> on Fri, 24 Dec 2004 10:00:52 -0600, "Donald
> Newcomb" <DRNewcomb@attglobal.NOT.net> wrote:
>
>
>
>
>
>
>
> Such areas are relatively rare and rural -- the great majority of tower
> spacing is within the maximum range of both GSM and CDMA.
BUT--doesn't that encompass a great majority of the land mass of the
United States -- the rural area. You are correct, however that the
majority of towers are not rural, that it is rare for GSM and CDMA rural
towers (compared to AMPS).
>
>
> Can you be more specific? I don't know of areas actually designed like that.
>
>
>
>
> My Sony Ericsson Z600 has worked well out to at least 30 km (near the normal
> 35 km range limit for GSM), which is greater than the great majority of tower
> spacing.
Yes, but I am more interested in what encompasses the majority of land
mass of North America, as I travel extensively. I do not doubt the
majority of towers are like that, however, the majority of towers do not
cover the majority of a given network's coverage area...the majority of
towers cover the majority of users.
| |
| Prilosec 2005-05-19, 11:54 am |
|
You are correct--the max legal power in AMPS is 3 watts, handheld AMPS ..6 watts. This is max power. They didn't want you to fry your brain by holding a 3 watt transmitter up to it! AMPS also had (s) a max capacity for calls per tower (somewhere around 830?). There were many more AMPS towers back in the day in the built-up areas for this reason, too. This made transition to lower powered digital less of a problem.
As I understand it, a digital signal of comparable power will travel farther than an AMPS signal because the digital signal is using basically CW and AMPS uses FM to carry voice. The FM requires more power so you can make out what the person is saying. CW signals are understandable for longer distances than FM because they are easier to interpret at the receiving end (like Morse Code). At least this is how I understand it to work.
"Carl." < usenetcarl@JUNKMAILh
otmail.com> wrote in message news:SLNyd.15459$yv2.46@fe2.texas.rr.com...
> "Tropical Haven" <user@example.net> wrote in message
> news:41CB8F8E.9080408@example.net...
>
> Speaking in general about the periods I am familiar with...
>
> Those big "bag phones" had 3-watt ability. Analog handhelds were .6 watts,
> and the bag phones had some kind of low-power mode for urban areas. Every
> analog tower was not spaced expecting all phones to run at 3 watts before
> digital service came along. I assume they had issues to deal with,
> especially since digital phones were even lower power, but without getting
> all complicated the short of it is that there was no sudden jump from 3
> watts to .002 watts.
>
>
| |
|
| Prilosec wrote:
>
> You are correct--the max legal power in AMPS is 3 watts, handheld AMPS
> .6 watts. This is max power. They didn't want you to fry your brain by
> holding a 3 watt transmitter up to it! AMPS also had (s) a max capacity
> for calls per tower (somewhere around 830?). There were many more AMPS
> towers back in the day in the built-up areas for this reason, too. This
> made transition to lower powered digital less of a problem.
> As I understand it, a digital signal of comparable power will travel
> farther than an AMPS signal because the digital signal is using
> basically CW and AMPS uses FM to carry voice. The FM requires more power
> so you can make out what the person is saying. CW signals are
> understandable for longer distances than FM because they are easier to
> interpret at the receiving end (like Morse Code). At least this is how I
> understand it to work.
dah-dah-di-dah di-dah-dit di-dah-dah-dit
dah-dah-di-dah di-dah-dit di-dah-dah-dit
dah-dah-di-dah di-dah-dit di-dah-dah-dit
dah-dah-di-dah di-dah-dit di-dah-dah-dit
<giggle> er.... <dit-dit-dit-dit-dit-dit-dit-dit-dit-dit>
--
jer
email reply - I am not a 'ten'
| |
| Dan Albrich 2005-05-19, 11:54 am |
| No nightmare- but yes, there are specific areas where you can just tell the
system was designed for the older phones. I90 across much of the state of
Montana is this way. A handheld phone inside a car will show full digital
signal, fading, fading, fading, no service, one bar service, two bars, then
full service and repeat.
In other words, you definitely get the feeling the tower spacing was
designed for 3W bagphones.
In my experience, especially in Montana, a small handheld digital phone can
work fine even while driving if you have an external antenna mounted on your
car. I use a glass mount kit which is less efficient (but easily installed)
which enables me to make and receive calls even in the remote sections of
I90 through Montana.
My experience has been that external antennas are really useful in many
places in the rural west. It can be the difference that allows you to make
or receive calls.
-Dan
PS: I spend almost all of my free time outside of towns, and most of the
time I have no cellular service whatsoever. Having the external antenna
increases my chances of being able to use the phone.
--
Eugene, Oregon -- Pacific Northwest
http://cell.uoregon.edu
| |
|
| Dan Albrich wrote:
> No nightmare- but yes, there are specific areas where you can just tell the
> system was designed for the older phones. I90 across much of the state of
> Montana is this way. A handheld phone inside a car will show full digital
> signal, fading, fading, fading, no service, one bar service, two bars, then
> full service and repeat.
> In other words, you definitely get the feeling the tower spacing was
> designed for 3W bagphones.
>
> In my experience, especially in Montana, a small handheld digital phone can
> work fine even while driving if you have an external antenna mounted on your
> car. I use a glass mount kit which is less efficient (but easily installed)
> which enables me to make and receive calls even in the remote sections of
> I90 through Montana.
>
> My experience has been that external antennas are really useful in many
> places in the rural west. It can be the difference that allows you to make
> or receive calls.
>
> -Dan
>
> PS: I spend almost all of my free time outside of towns, and most of the
> time I have no cellular service whatsoever. Having the external antenna
> increases my chances of being able to use the phone.
>
A lot of people expect waaay too much performance from a little stubby
antenna from inside their car. External antennas offer greater height
(above roofline, less shading) and increased signal capture ratio
(improved signal level to the receiver). While the longer coax
connection to the antenna can offset some of these advantages, it's not
enough to eliminate an external antenna's usefulness. Since I've
already ditched my Nokia car kit, I'm now shopping for a new car kit for
the V551, and the dual-band antenna will reused.
--
jer
email reply - I am not a 'ten'
| |
| John Navas 2005-05-19, 11:54 am |
| [POSTED TO alt.cellular.attws - REPLY ON USENET PLEASE]
In <DridnVWlPMgPpFLcRVn-vg@comcast.com> on Sun, 26 Dec 2004 14:22:12 -0800,
"Dan Albrich" <junkmail@shaney.uoregon.edui> wrote:
>No nightmare- but yes, there are specific areas where you can just tell the
>system was designed for the older phones. I90 across much of the state of
>Montana is this way. A handheld phone inside a car will show full digital
>signal, fading, fading, fading, no service, one bar service, two bars, then
>full service and repeat.
>In other words, you definitely get the feeling the tower spacing was
>designed for 3W bagphones.
>
>In my experience, especially in Montana, a small handheld digital phone can
>work fine even while driving if you have an external antenna mounted on your
>car. I use a glass mount kit which is less efficient (but easily installed)
>which enables me to make and receive calls even in the remote sections of
>I90 through Montana.
>
>My experience has been that external antennas are really useful in many
>places in the rural west. It can be the difference that allows you to make
>or receive calls.
>
>-Dan
>
>PS: I spend almost all of my free time outside of towns, and most of the
>time I have no cellular service whatsoever. Having the external antenna
>increases my chances of being able to use the phone.
True, but there can be considerable differences between handsets, in transmit
power, antenna efficiency, and receive sensitivity. For example, I know of
stretches of Interstate where my old Ericsson T39m with optional IAT-10
high-performance antenna was able to hold signal continuously while a small
sexy Nokia with internal antenna was going in and out of signal as you
describe. I never felt the need for an external antenna with the T39m/IAT-10.
Moral: If you frequent rural areas, choose your handset with care.
--
Best regards, HELP FOR CINGULAR GSM & SONY ERICSSON PHONES:
John Navas <http://navasgrp.home.att.net/#Cingular>
| |
| Traveling Man 2005-05-19, 11:54 am |
| On Sun, 26 Dec 2004 08:20:21 -0600, Jer wrote:
> dah-dah-di-dah di-dah-dit di-dah-dah-dit
> dah-dah-di-dah di-dah-dit di-dah-dah-dit
> dah-dah-di-dah di-dah-dit di-dah-dah-dit
> dah-dah-di-dah di-dah-dit di-dah-dah-dit
dit-dit-dit-dah-dit-dah
| |
| Dan Albrich 2005-05-19, 11:54 am |
| > Moral: If you frequent rural areas, choose your handset with care.
I agree the handset selection matters, but not as much as an external
antenna connected to any phone. Partly its the whole faraday cage thing,
but you cannot underestimate the improvement of a good antenna mounted
on a good ground-plane like the roof of a car.
I find traveling with multiple handsets, the one that is connected to my
external antenna always wins, and by far.
-Dan
--
Eugene, Oregon -- Pacific Northwest
http://cell.uoregon.edu
>
> --
> Best regards, HELP FOR CINGULAR GSM & SONY ERICSSON PHONES:
> John Navas <http://navasgrp.home.att.net/#Cingular>
|
|
|
|
|