Who Dropped the Call?

Assume that you have two CDMA cell phones with the call drop feature
enabled. Both of the phones are receiving a good signal and the users of the
phone are in a stationary position. One of the users notices that the sound
of the other person's voice is becoming "choppy". The other person does not
notice anything and the conversation sounds perfectly fine to her. The
choppiness persists for about 30 seconds and then the connection drops.
Immediately before the connection drops, I cannot hear the other person, but
she can hear me just fine without any problems. Neither of the phones
displays the call-dropped indication or makes the call-dropped tone, however
both phones know that the connection is dropped because the minute counter
has stopped.

What causes this problem? It seems that one of the phones should have known
that it dropped the call. One phone is a Sanyo on SPCS and the other phone
is a Motorola on Verizon. I hear the choppiness on the Sanyo phone and the
person the Motorola phone hears perfect voice quality before the call is
dropped.

-mij

---

› See More: Who Dropped the Call?

Don't think I know the answer to your question but just wanted to add
that on the times that I've had a bad connection usually one person can
hear everything fine and the person on the other end cannot. So it
seems that a bad connection is frequently only bad on one end.

[email protected] wrote:

> Don't think I know the answer to your question but just wanted to add
> that on the times that I've had a bad connection usually one person can
> hear everything fine and the person on the other end cannot. So it
> seems that a bad connection is frequently only bad on one end.

Without being a techie...
Consider how little power the phone is putting out versus a tower and the
effect becomes somewhat understandable. It probably is the sending phone
that is causing the problem.

LB

Mij Adyaw wrote:
> Neither of the phones
> displays the call-dropped indication or makes the call-dropped tone, however
> both phones know that the connection is dropped because the minute counter
> has stopped.
>
> What causes this problem?

That's a lot like saying "why do cars break?" There can be any number
of factors on either end that causes a call to drop. The most common of
course, are one or both handsets being in a bad signal area.

> It seems that one of the phones should have known
> that it dropped the call.

I've found that the dropped call indicator is not always correctly
recognize a call as being dropped. Usually the dropped call indicator
will come on if you handset decides that the signal is too weak and
terminates the connection. If the cell site, however, decides that it
cannot "hear" your phone well enough even though your phone can hear the
site loud and clear, then the cell site will terminate the connection,
and this often looks to the handset as if the call ended normally.

An important thing to realize is that our phones' signal strength meters
only tell half the story. It's all fine and good if we're getting a
strong clear signal from the cell site, but that cell site also has to
be able to hear us for a call to be successful. Our handsets are at a
disadvantage because they operate with such low power (0.06 watts max,
as opposed to many hundreds of watts for an average cell tower), so it
is much easier to block the signal going to the tower, than it is the
reverse.

> One phone is a Sanyo on SPCS and the other phone
> is a Motorola on Verizon. I hear the choppiness on the Sanyo phone and the
> person the Motorola phone hears perfect voice quality before the call is
> dropped.

Two possibilities:

1. The Sanyo phone's forward channel (cell site to phone) reception from
the Sprint tower was poor. Since the Motorola handset on Verizon could
hear you loud and clear, the reverse channel (phone to cell site) on the
Sanyo was strong and sufficient. But your handset didn't know this
because of the poor downlink, and so it chose to terminate the call. Or,

2. The Motorola phone had a strong forward channel from the Verizon cell
tower, but the Verizon site serving that phone could not get clear
reception of the reverse channel coming from the Motorola. Because the
reverse link's bit error rate was too high, the Verizon tower terminated
the connection.

I'd have to say that #2 is a bit more likely than #1. It would explain
why both phones ended the call without realizing that there was a
dropped-call condition. With the Verizon site terminating the call,
your Sprint phone would assume the call ended normally because it saw no
problems on its end, while the Motorola would be forced to assume the
same because it was receiving just fine too, even though the Verizon
tower couldn't hear the Motorola phone. If #1 had happened, then your
phone most certainly would have given you a dropped call tone if it was
properly configured to do so.




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

Mij Adyaw wrote:
> Neither of the phones
> displays the call-dropped indication or makes the call-dropped tone,
however
> both phones know that the connection is dropped because the minute
counter
> has stopped.
>
> What causes this problem?

That's a lot like saying "why do cars break?" There can be any number
of factors on either end that causes a call to drop. The most common of
course, are one or both handsets being in a bad signal area.

> It seems that one of the phones should have known
> that it dropped the call.

I've found that the dropped call indicator is not always correctly
recognize a call as being dropped. Usually the dropped call indicator
will come on if you handset decides that the signal is too weak and
terminates the connection. If the cell site, however, decides that it
cannot "hear" your phone well enough even though your phone can hear the
site loud and clear, then the cell site will terminate the connection,
and this often looks to the handset as if the call ended normally.

An important thing to realize is that our phones' signal strength meters
only tell half the story. It's all fine and good if we're getting a
strong clear signal from the cell site, but that cell site also has to
be able to hear us for a call to be successful. Our handsets are at a
disadvantage because they operate with such low power (0.06 watts max,
as opposed to many hundreds of watts for an average cell tower), so it
is much easier to block the signal going to the tower, than it is the
reverse.

> One phone is a Sanyo on SPCS and the other phone
> is a Motorola on Verizon. I hear the choppiness on the Sanyo phone
and the
> person the Motorola phone hears perfect voice quality before the call is
> dropped.

Two possibilities:

1. The Sanyo phone's forward channel (cell site to phone) reception from
the Sprint tower was poor. Since the Motorola handset on Verizon could
hear you loud and clear, the reverse channel (phone to cell site) on the
Sanyo was strong and sufficient. But your handset didn't know this
because of the poor downlink, and so it chose to terminate the call. Or,

2. The Motorola phone had a strong forward channel from the Verizon cell
tower, but the Verizon site serving that phone could not get clear
reception of the reverse channel coming from the Motorola. Because the
reverse link's bit error rate was too high, the Verizon tower terminated
the connection.

I'd have to say that #2 is a bit more likely than #1. It would explain
why both phones ended the call without realizing that there was a
dropped-call condition. With the Verizon site terminating the call,
your Sprint phone would assume the call ended normally because it saw no
problems on its end, while the Motorola would be forced to assume the
same because it was receiving just fine too, even though the Verizon
tower couldn't hear the Motorola phone. If #1 had happened, then your
phone most certainly would have given you a dropped call tone if it was
properly configured to do so.




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On Mon, 21 Mar 2005 14:09:45 -0500, Isaiah Beard
<[email protected]> wrote:
>Our handsets are at a
>disadvantage because they operate with such low power (0.06 watts max,
>as opposed to many hundreds of watts for an average cell tower),

I believe you mean 0.6 W (600 mW). And I was told the typical cell site
transmits at a power of 20 watts.

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

Bob Scheurle wrote:
> On Mon, 21 Mar 2005 14:09:45 -0500, Isaiah Beard
> <[email protected]> wrote:
>
>>Our handsets are at a
>>disadvantage because they operate with such low power (0.06 watts max,
>>as opposed to many hundreds of watts for an average cell tower),
>
>
> I believe you mean 0.6 W (600 mW).

Actually, we're both wrong. For CDMA, maximum transmit power is
typically .250 watts. 0.6 watts is the maximum Tx power for AMPS handsets.


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Welcome to the GET IT NOW network and "Can you hear me now" marketing
slammed network. Instead of making regular phone calls better which has ALOT
to go all the money was dumped into another "luxury" for kids. Vcast is it?
Video on a cell phone. Got to be kidding me. Can't even handle all the
volume of the calls at a peak time let alone video that probably hogs
resources. Sorry, I would rather my premium monthly payment go to some thing
else then teenager based functions. Just like I've been saying for
months...it's only a matter of time....Verizon will be hurting for
customer's. I can't WAIT until the day they have to drop prices, offer
promotions like keeping all your minutes you pay for and stuff like earlier
night starts.

"Mij Adyaw" <[email protected]> wrote in message
news:%qt%d.113395$bu.92445@fed1read06...
> Assume that you have two CDMA cell phones with the call drop feature
> enabled. Both of the phones are receiving a good signal and the users of
> the phone are in a stationary position. One of the users notices that the
> sound of the other person's voice is becoming "choppy". The other person
> does not notice anything and the conversation sounds perfectly fine to
> her. The choppiness persists for about 30 seconds and then the connection
> drops. Immediately before the connection drops, I cannot hear the other
> person, but she can hear me just fine without any problems. Neither of the
> phones displays the call-dropped indication or makes the call-dropped
> tone, however both phones know that the connection is dropped because the
> minute counter has stopped.
>
> What causes this problem? It seems that one of the phones should have
> known that it dropped the call. One phone is a Sanyo on SPCS and the other
> phone is a Motorola on Verizon. I hear the choppiness on the Sanyo phone
> and the person the Motorola phone hears perfect voice quality before the
> call is dropped.
>
> -mij
>
>

Wow, you're regular as clockwork. I checked back a long
ways and it seems that you get fired up right about the
21st or shortly thereafter every month. I think I have it
figured out. You're double dosing on the weekends. If
you double dosed every day you'd run out in the middle
of the month...

-Quick

Xman wrote:
> Welcome to the GET IT NOW network and "Can you hear me
> now" marketing slammed network. Instead of making regular
> phone calls better which has ALOT to go all the money was
> dumped into another "luxury" for kids. Vcast is it? Video
> on a cell phone. Got to be kidding me. Can't even handle
> all the volume of the calls at a peak time let alone
> video that probably hogs resources. Sorry, I would rather
> my premium monthly payment go to some thing else then
> teenager based functions. Just like I've been saying for
> months...it's only a matter of time....Verizon will be
> hurting for customer's. I can't WAIT until the day they
> have to drop prices, offer promotions like keeping all
> your minutes you pay for and stuff like earlier night
> starts.
>
> "Mij Adyaw" <[email protected]> wrote in message
> news:%qt%d.113395$bu.92445@fed1read06...
>> Assume that you have two CDMA cell phones with the call
>> drop feature enabled. Both of the phones are receiving a
>> good signal and the users of the phone are in a
>> stationary position. One of the users notices that the
>> sound of the other person's voice is becoming "choppy".
>> The other person does not notice anything and the
>> conversation sounds perfectly fine to her. The
>> choppiness persists for about 30 seconds and then the
>> connection drops. Immediately before the connection
>> drops, I cannot hear the other person, but she can hear
>> me just fine without any problems. Neither of the phones
>> displays the call-dropped indication or makes the
>> call-dropped tone, however both phones know that the
>> connection is dropped because the minute counter has
>> stopped.
>>
>> What causes this problem? It seems that one of the
>> phones should have known that it dropped the call. One
>> phone is a Sanyo on SPCS and the other phone is a
>> Motorola on Verizon. I hear the choppiness on the Sanyo
>> phone and the person the Motorola phone hears perfect
>> voice quality before the call is dropped.
>>
>> -mij

"Isaiah Beard" <[email protected]> wrote in message
news:[email protected]...
> Bob Scheurle wrote:
>> On Mon, 21 Mar 2005 14:09:45 -0500, Isaiah Beard
>> <[email protected]> wrote:
>>
>>>Our handsets are at a disadvantage because they operate with such low
>>>power (0.06 watts max, as opposed to many hundreds of watts for an
>>>average cell tower),

A typical CDMA tower will put out 16W max. In most citys, this power is
trimmed back to 8 W. The concept is exactly as you state, the handset only
puts out a miniscule amout of power. Having all that power broadcast from a
tower will get the signal to the handest, but the handset would only be
talking at a whisper back to the tower. So, there is no reason to put out
more power then that.

Oh, and as a tidbit, that two way walkietalkie you bought at the sporting
goods store typically puts out 5 W. Almost as much as the city CDMA tower.

>>
>>
>> I believe you mean 0.6 W (600 mW).
>
> Actually, we're both wrong. For CDMA, maximum transmit power is typically
> .250 watts. 0.6 watts is the maximum Tx power for AMPS handsets.
>
>
> --
> E-mail fudged to thwart spammers.
> Transpose the c's and a's in my e-mail address to reply.

There's also the probability of sorry-*ss Lucent or Nortel equipment.
These bugs should
have been fixed years ago. Instead the poor customer is blamed.

JG