Minimum RF Performance?

Why does the customer have to be concerned with which cell phone provides
the best reception if he lives in a low signal area? I have seen many folks
try to purchase the phone that has the best reception. Note that the phone
with the best reception is not always the most expensive phone.

Why can't the cell phone manufacturers establish standards for RF
performance so that all cell phones sold by a cellular carrier will provide
adequate reception in the most minimal signal conditions?

It seems that the cell phone carriers could solve this problem by
establishing better RF performance standards for all cell phone suppliers.
Therefore the reception of all makes and models of phones would be
identical.

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› See More: Minimum RF Performance?

"Bubba DeBub" <[email protected]> wrote in message
news:rZJ4e.29554$v26.20895@fed1read06...
> Why does the customer have to be concerned with which cell phone provides
> the best reception if he lives in a low signal area? I have seen many
folks
> try to purchase the phone that has the best reception. Note that the phone
> with the best reception is not always the most expensive phone.
>
> Why can't the cell phone manufacturers establish standards for RF
> performance so that all cell phones sold by a cellular carrier will
provide
> adequate reception in the most minimal signal conditions?
>
> It seems that the cell phone carriers could solve this problem by
> establishing better RF performance standards for all cell phone suppliers.
> Therefore the reception of all makes and models of phones would be
> identical.
>
I hope that other factors such as cost, features, size, battery life are
also considered, maybe the carriers can offer a choice of phones so I can
pick the one I want. What we need is standards on is the number of picals in
camera phones and the height of 50% fall survival rate. By the way to get
equal RF performance you don't need to change the phones, the carrier could
mesure the phones performance and add an index to the table where the esn is
stored and handicap the phone at the cell site now all phones are equal (
lowest common denominator ).

On Tue, 5 Apr 2005 21:55:51 -0700, "Bubba DeBub"
<[email protected]> wrote:
>Why can't the cell phone manufacturers establish standards for RF
>performance so that all cell phones sold by a cellular carrier will provide
>adequate reception in the most minimal signal conditions?

Because there's no free lunch, and improving RF performance may result in
trade-offs in areas like size, weight, battery life, cost, etc. Your
question is like suggesting that all cars and SUVs get 45 mpg.

--
Bob Scheurle | "There's nobody getting
[email protected] | rich writing software."
Remove X's and dashes | -- Bill Gates, March 1980

In message <[email protected]> Bob Scheurle
<[email protected]> wrote:

>On Tue, 5 Apr 2005 21:55:51 -0700, "Bubba DeBub"
><[email protected]> wrote:
>>Why can't the cell phone manufacturers establish standards for RF
>>performance so that all cell phones sold by a cellular carrier will provide
>>adequate reception in the most minimal signal conditions?
>
>Because there's no free lunch, and improving RF performance may result in
>trade-offs in areas like size, weight, battery life, cost, etc. Your
>question is like suggesting that all cars and SUVs get 45 mpg.

However, requiring the RF performance to be documented fully in
understandable terms (in other words, some sort of index or aggregate
number that indicates which phone is "better" in terms of RF
performance)




--
'Tis far better to have snipped too much than to never have snipped at all.

On Wed, 06 Apr 2005 04:17:37 -0600, DevilsPGD wrote:

>
> However, requiring the RF performance to be documented fully in
> understandable terms (in other words, some sort of index or aggregate
> number that indicates which phone is "better" in terms of RF
> performance)

So you want a color scale? That is not going to happen the way you want it
for a few reasons. Keep in mind they do publish the RF radiation along
with various tests on it's output with the FCC which you can look up if
you so choose. First off to design a phone that has a great feature set
and the best reception you have to put money into the best hardware you
can find, risk producing a large/heavy phone along with lower battery
life. These kind of considerations would be fine if it wasn't for the fact
that every cell phone manufacture is trying to out sell each other and the
more they can cut their costs along with producing a product with the
feature set/size their customers want the more they will sell. The second
reason why they won't implement a rating system is because of how
impractical measuring RF reception on a moving low powered device that is
excepted to work with almost no signal(according to some people) is. Since
the radios the phones use may not even be the same model or utilize the
same antenna design listing a scale that will be accurate, from a consumer
prospective, would take time and money that would only hurt cell phone
sales in the long run and be dumbed down to a point where it can't be used
for anything useful. Such as how the signal bars on a phone allow a glance
at your probably to make a call with only your specific phone and not
others.

When I mention that the scale would hurt cell phone sales the reasoning
behind this is that who wants to buy a phone with a low reception rating?
With this scale people will only want to buy the best within their price
range. Wither or not this scale means anything it will make people
think that this phone with a rating of 7 is better then this other one
with a 5. By putting a rating system that most likely will have no direct
real world(usable) relation all cellphone providers allow themselves to do
is build a system where that as soon as you put a cell phone on the shelf
it's value is related not to it's feature set or actual performance but to
a number that is in place to make people think the phone "might" work
everywhere they take it.

On Tue, 5 Apr 2005 21:55:51 -0700, Bubba DeBub wrote:

> Why can't the cell phone manufacturers establish standards for RF
> performance so that all cell phones sold by a cellular carrier will provide
> adequate reception in the most minimal signal conditions?

There is only so much space in a cell phone to keep the size managable.
When users demand add-ons like cameras, memory cards, MP3 players, etc.
compromises have to be made on the RF circuitry.

It's interesting to note that one of the best RF performers was the simple
Moto StarTac series. No frills - just great performance.

Bubba DeBub wrote:

> Why can't the cell phone manufacturers establish standards for RF
> performance so that all cell phones sold by a cellular carrier will provide
> adequate reception in the most minimal signal conditions?

Actually, there are minimum standards that are often set by the wireless
carrier. When a phone is takem in and diagnostics are done on it, RF
performance is one of the indicators used to judge whether a phone is
considered "in spec." It must meet a minimum performance level, it must
be able to step through a range of transmit levels, and at least in the
case of CDMA, it must not exceed a certain maximum level (because a
phone that transmits too powerfully on CDMA will unnecessarily raise the
noise floor and degrade the performance of other phones in the same sector).

That said, a minimum is just that, a minimum. Some phones are still "in
spec" but perform better than others. Carriers can conceiveably make
their standards more stringent and demand better minimum performance,
but that still won't eliminate discussions about what phones are better
at reception than others. Customers will continue to push the envelope
on which phones work well or better than others in fringe areas, for as
long as fringe areas continue to exist.

The only way to eliminate this is to make each and every phone uniform
in size, shape, and design, and to completely replace the current base
of phones out in the field with this uniform model. Considering that
cell phones have become a fashion accessory and appeal to various tastes
and styles, some customers want more out of their phones (camera, PDA,
blutooth, data) than others, and handset makers want to be able to make
their designs unique from their competitors, this just isn't going to
happen anytime soon.


--
E-mail fudged to thwart spammers.
Transpose the c's and a's in my e-mail address to reply.

I haven't really noticed much difference in reception among the various
phones that I've used and tested. They were all about the same.

CellGuy wrote:

> It's interesting to note that one of the best RF performers was the simple
> Moto StarTac series. No frills - just great performance.

Ditto!

I dont want the extra crap, just a phone that is readable, comfortable,
and doesnt drop calls all the time.

I still like the startac better than my VX4400

-Pete

Just for the record if I had to pick one phone the StarTac 7867 was the
worst performing phone I've ever used. It dropped more calls than any
other phone, not to mention the UI was something I could never get used
to.

"Bubba DeBub" <[email protected]> wrote in message
news:rZJ4e.29554$v26.20895@fed1read06...
> Why can't the cell phone manufacturers establish standards for RF
> performance so that all cell phones sold by a cellular carrier will
> provide adequate reception in the most minimal signal conditions?

They do, but radio propagation is fickle enough that without visiting each
and every square meter of space that they're attempting to cover, there's no
way they can be 100% certain the phone will operate in what they consider
their coverage area.

Of course, marketing departments within some of the wireless companies are
much worse about 'closing in (known) gaps' on their coverage maps than
others... :-(

> It seems that the cell phone carriers could solve this problem by
> establishing better RF performance standards for all cell phone suppliers.
> Therefore the reception of all makes and models of phones would be
> identical.

Unless you want all the phones to use the exact same hardware and software,
that just isn't going to happen. Even then, there's enough statistical
variation in RF component production that some phones will end up getting
noticeably better reception than others.

At the end of the day, wireless system desginers use statistical models to
set performance specs for phones. E.g., with so much output power, they
figure they can achieve a decent bit error rate in, say, 99% of the time.
Usually you're looking at a normal distribution, so going from covering,
say, 99% of the scenarios to 99.9% can require, e.g., a ten-fold increase
in, say, power, which makes the phone considerably bigger, shortens battery
life, etc. In other words, at some point it's "just not worth it" to trade
off one design parameter for another.

Engineering is all about making intelligent trade-offs to achieve an ends...


>
>
>
>
>
>

"Central" <[email protected]> wrote in message
news[email protected]...
> from a consumer
> prospective, would take time and money that would only hurt cell phone
> sales in the long run and be dumbed down to a point where it can't be used
> for anything useful.

I agree it would probably have to be dumpbed down to the point where it
isn't useful, although OVERALL sales wouldn't suffer -- it's just which
manufacturer gets the sale that could change.

I'd first like to see regular analog TVs and AM/FM radios provide
sensitivity ratings -- they're still simply enough you could get a
reasonably standardized, useful result that SOME consumers might make use
of.

I do think that marketing departments tend to be overly fearful of
publishing technical information; I believe their flaw is in thinking that
many people would consider it when, in actuality, the vast majority of
consumers couldn't care less about the phone's technical RF performance.
Look at cars and cameras -- magazines such as Car & Driver and Professional
Photographer produce very detailed technical test results that some people
use as part of their buying decision, but the vast majority of people buy
cars and cameras based on the features 'marketed' to them, no technical
questions asked.

On the other hand, far too many people think that "MHz" alone is what they
should chose computers by... :-(

"DevilsPGD" <[email protected]> wrote in message
news:[email protected]...
> However, requiring the RF performance to be documented fully in
> understandable terms (in other words, some sort of index or aggregate
> number that indicates which phone is "better" in terms of RF
> performance)

It just can't be done. As I mentioned, try something simpler first --
computers. How do you go about boiling their performance down to just one
number that lets you choose the better one?

"Joel Kolstad" <[email protected]> wrote in message news:[email protected]...
> "DevilsPGD" <[email protected]> wrote in message
> news:[email protected]...
>> However, requiring the RF performance to be documented fully in
>> understandable terms (in other words, some sort of index or aggregate
>> number that indicates which phone is "better" in terms of RF
>> performance)
>
> It just can't be done. As I mentioned, try something simpler first --
> computers. How do you go about boiling their performance down to just one
> number that lets you choose the better one?

I don't think the OP is asking for an overall performance measurement,
just the RF sensitivity, which is only one parameter, and is indeed
measurable. I've seen RF sensitivity spec'd for high performance receivers
such as military and ham shortwave radios, but never for consumer
devices. Manufacturers consider it to be sensitive proprietary information.

--
John Richards

In message <[email protected]> "Joel Kolstad"
<[email protected]> wrote:

>"DevilsPGD" <[email protected]> wrote in message
>news:[email protected]...
>> However, requiring the RF performance to be documented fully in
>> understandable terms (in other words, some sort of index or aggregate
>> number that indicates which phone is "better" in terms of RF
>> performance)
>
>It just can't be done. As I mentioned, try something simpler first --
>computers. How do you go about boiling their performance down to just one
>number that lets you choose the better one?
>

Fair enough -- Give me a set of 5 numbers which are consistent from
manufacturer to manufacturer.

Let me decide which metric is more important to *me* -- As it is, there
is virtually no information on RF performance in any way, shape or form
on any of the cell phone boxes I have here.


--
Americans couldn't be any more self-absorbed if they were made from equal
parts water and papertowel.
-- Dennis Miller