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Comment: Re: heres another lie. (Score 1) 237

by jsveiga (#49102499) Attached to: Ten Lies T-Mobile Told Me About My Data Plan

Annoyingly, restricting background data isn't available when you select the "Android OS" "app", so the only way to really stop a (non rooted) Android phone to silently eat up your data plan is to completely disable cellular data. Whenever you need it, enable it - knowing that while you are using it, "Android OS" is doing its thing too.
I miss how Symbian respected the fact that you were the one paying for the service, no hacking required.

Comment: Re: The new power supplies may be sensitve to EMP (Score 1) 192

by jsveiga (#49011709) Attached to: Xenon Flashes Can Make New Raspberry Pi 2 Freeze and Reboot

In the US, in medieval times, cell phones used TDMA (IS136) or CDMA (IS95/2000).
TDMA is time-division multiplex, which means the phone radio would turn on and off on a fixed cadence to allow for other phones to share the same frequency channel. At the start of a call (either to or from the cell phone), the cell network still doesn't know how attenuated the phone signal will arrive, so typically the first communication bursts from the phone would be sent with much more power than the subsequent ones, when the cell could tell the phone "whoa, you can lower your voice, I can hear you very well" (power control).
That was why the phones would interfere with other devices just when a call was about to start (before the phone rings, the cell and the network have already established comms).
Europe was right, and everybody went GSM, which then added WCDMA (UMTS, LTE, "3G", "4G").
GSM is also a TDMA technology, so when your phone is in GSM mode, it may also create the same tick-tick-tick-brrrrrz interference for the same reasons.

Comment: Re: Gray-market Nintendo smuggling (Score 2) 111

by jsveiga (#48786477) Attached to: Nintendo Puts Business In Brazil On Hiatus

There are a lot of shades of gray.
For years, Sony ignored Brazil in regards to the Playstation market. There was no PS2 nor PS3 officially sold nor supported by Sony in the country, no way to select Brazil when creating a PSN account, no Sony warranty nor repair centers, Nothing.
Nevertheless, nobody cared, and most people didn't even notice (until they tried to register a PSN account and had to resource to hacks to be able to register one as being in the US and makw Sony accept a Brazilian international credit card).
The consoles could be purchased by several "channels", from black to almost white gray market: From smugglers, by going to the US an bringing one, from legit stores who would legally import them directly and even provided a 1-year warranty, etc.
Sony did not spend a dime with the market. They would't even answer support questions from Brazilian customers, although there was a lot of money coming in from the indirect sales of the consoles, game sales, and PSN purchases.
After Brazil was finally "recognized" by Sony, soon US PSN accounts would no longer accept Brazilian international credit cards via the "hack". Makes one wonder if the well-known hacks (merely using a US city with the same ZIP code of your Brazilian city would work, for example) was tolerated before so Sony could get the profits without the burden of officially supporting the customers.
Maybe Nintendo just wants to save money with the same business model.

Comment: it is so much more than that!! (Score 4, Funny) 231

by jsveiga (#41367623) Attached to: Apple iPad 2 As Fast As the Cray-2 Supercomputer

It has been demonstrated that the ipad 2 is lighter than an Apple II.

The ipad 2 user interface has been tested and proven much better than the Zilog Z80's.

On a blind test, the ipad's screen resolution has been voted subjectively better than the MSX's!

And an independent research confirmed that it has more available apps than the HP41C!

In a random test with a control group, 3 out of 5 teenagers prefer the ipad when offered the option of an ipad or a Newton, and 2 out of 4 girls prefer the ipad over Justin "Beaver".

Oh my God, the ipad is really the best thing in the whole universe! No, it has been demonstrated that it is better than 5 universes put together with whipped cream and strawberries on top!!

PlayStation (Games)

+ - Sony PlayStation Network Down for a 'Day or Two'->

Submitted by Anonymous Coward
An anonymous reader writes "Sony said Thursday that its PlayStation Network, the online service that connects Sony's game consoles like the PlayStation 3, may be out for a "full day or two" due to an unexpected and unexplained outage.
Sony first confirmed the outage at 5:50 PM Wednesday night, when Patrick Seybold, the senior director of corporate communications and social media, reported that "We're aware certain functions of PlayStation Network are down," Seybold said. "We will report back here as soon as we can with more information."
At 9:34 AM on Thursday, Seybold added the latest information, which will be grim news for PlayStation players.
"While we are investigating the cause of the Network outage, we wanted to alert you that it may be a full day or two before we're able to get the service completely back up and running," Seybold added. "Thank you very much for your patience while we work to resolve this matter. Please stay tuned to this space for more details, and we'll update you again as soon as we can."
The PlayStation Network is used to deliver downloadable games, movies, music, and other services to consumers who own a PlayStation 3 console. But the network also serves as the infrastructure for multiplayer games, meaning that gamers won't be able to play a multiplayer game like "Call of Duty" until Sony fixes the outage.
Reports also said that Sony Computer Entertainment Europe had posted its suspicions about a hacking attempt, but by press time, the European PlayStation blog had been apparently edited to mimic the U.S. version.
"As you are no doubt aware, the current emergency outage is continuing this afternoon and all Sony Online Network services remain unavailable," Sony Computer Entertainment Europe PS blog manager James Gallagher posted today. "Our support teams are investigating the cause of the problem, including the possibility of targeted behavior by an outside party. If the reported Network problems are indeed caused by such acts, we would like to once again thank our customers who have borne the brunt of the attack through interrupted service."
The outage apparently is not the work of Anonymous, the industry hacker group that had turned its ire to Sony, announcing a worldwide protest in the wake of Sony's litigation against George Hotz, which was eventually settled, but not before Hotz vowed to join the boycott as well.
"ATTENTION: For everyone coming here complaining about the PSN or inquiring about it, We Do Not Know What Happened," a member of the group posted on its Facebook page. "This is not the work of Anonymous.""

Link to Original Source

Comment: A sad sad day (Score 1) 1

by jsveiga (#35172118) Attached to: Nokia and Microsoft form cell phone partnership

Nobody expected Symbian to survive much longer anymore, but going Microsoft was the dumbest option.

The largest hardware market share with the worst possible OS. Could only come from an American mindset CEO: "Hey, look! An ultra fast way to make the Windows Mobile market share go up and get fat bonuses quick! Let's show these fancy Europeans how a real OS should be!"

Why didn't they go Android then?

Nokia fanboys (like myself) are there for the intrinsic cool factor of a Nokia phone (no matter if cold numbers point to better hardware or more modern OSs out there). They just needed to keep the flame alive sprinkling some edgy tech here and there, no need to sell their souls to the devil. Apple lives up on coolness alone.

What a way to completely "finnish" up with the coolness...

Joao S Veiga

Comment: Re:Formula change (Score 1) 534

by jsveiga (#32783426) Attached to: Apple To Issue a 'Fix' For iPhone 4 Reception Perception

Please excuse me if this sounds pedantic but it is relevant for the subject.

When we're talking about levels of -51, -91, -113, etc., these are probably GSM signal levels, and the unit should be dBm.

dB alone is just a ratio, which is suitable for indicating for example Ec/Io, which is sort of signal to noise ratio when in WCDMA mode (the iPhone, being an UMTS phone can use GSM or WCDMA). -113, -51 do not look like Ec/Io values (these are good around -10dB).

When in WCDMA mode, Ec/Io is much more relevant than signal level and I believe phones show bars proportional to that. When in GSM mode, signal level is more relevant, and phones show bars proportional to that.

In WCDMA mode, the level is much less important than the phone capacity of extracting meaning out of the noise. You may have a very low signal level, but if the Ec/Io is good, you can place a call. You may have a high signal level, and not be able to place a call if your Ec/Io is poor. This is also true (but not as critical) for GSM mode.

A conclusive test or comparison should not be based only on signal levels, but use a proper GSM/WCDMA phone test equipment, capable of generating different signal levels (GSM) and Ec/Io (WCDMA), then collecting the phone's received Bit Error Rate, or Frame Error Rate. Believing in the level information the phone itself informs and relating that to dropped calls is quite subjective, as it is not a controlled environment, and what the phone informs may be wrong.

In the analog times (AMPS), signal level was all you could measure, and interference just meant the sound would be crappy (and the occasional undesired "group call"). If there was a good signal level, you could place the call (but the quality could be awful, there was no way of knowing).

With digital, bit error rate is what matters, and signal quality is more important than signal level. As long as the received signal level is above the phone's sensitivity (and here is a place where you separate manufacturers who know their RF from the ones who don't), then that's "level enough". It doesn't help to have a lot of signal strength (power) if due to the signal quality (signal/noise) or your hardware/software quality you cannot pull the useful data from it.

In the digital age, it's not the size of your signal which matters, but what you manage to do with it.

Comment: Re:Formula change (Score 1) 534

by jsveiga (#32783276) Attached to: Apple To Issue a 'Fix' For iPhone 4 Reception Perception

Good point, but just to add some more information, here are my two cents:

When an UMTS phone (like the iPhone) is in GSM (and GPRS and EDGE) modes, the signal to noise could be measured by comparing what the receiver gets during its receive timeslot (GSM/GPRS/EDGE use Time Division Multiplex Access - TDMA) against what it gets out of its receiving timeslot. Nevertheless, this is not how the phones measure the signal quality or signal to noise, which as you pointed out is more important.

What is actually considered as a measure of signal quality in GSM is called RxQual (receive quality), which is derived from actual Bit Error Rates (this is part of the GSM/UMTS standard; there is a table relating RxQual to BER in GSM 05.08). The phone reports RxLev (level) and RxQual back to the network for the network to decide about changing the serving cell site (handover). The phone bars however (as far as I know) show something logarithmically related to signal level. This may be not a good indication if you have a LOT of signal, but it's all interference (good RxLev, bad RxQual).

When a UMTS phone is in WCDMA mode, then signal to noise is even more important, but it is measured by the phone by comparing the level it pulls out of the "noise" when using the correct scrambling code against the total received level. Remember that WCDMA uses codes to separate each data "stream", all mixed in the same wideband frequency channel. The more codes in use, the more "noise" you see out of your own code. This measurement is generally called Ec/Io (UMTS standard 3GPP TS 25.133), and is also reported back to the network, with other information, for handover decisions.

I *think* that when in WCDMA mode the phone bars are related to Ec/Io, not actual signal level. If not, they should, as receiving a lot of signal "power" in your antenna when in WCDMA mode does not mean you can get/maintain calls. In GSM mode the "noise" is interference in the GSM frequency, generally coming from (poor) network design allowing channel reuse in cellsites that can "reach" the same spot. In WCDMA, a lot of "noise" comes from normal network usage, so it's a fact of life. Have you heard that CDMA/WCDMA cell coverage "shrinks" with traffic? This is why. You may have good WCDMA/CDMA quality off peak usage hours but "no coverage" at the same spot during peak hours.

All these measurements are ready to use in the phone's UMTS chipset, as they are mandatory by the standards (which by the way are freely downloadable from 3gpp.org), and the standard is strict about how they are measured/calculated - phones have to do it right to pass compliance tests.

Apple (intentionally or not) may have converted them wrong to the bar display (maybe they did not figure out the logarithms right, being newbies in the RF world...), but the measurements could not be wrong, or the phone shouldn't have passed conformity tests.

Comment: Re:Interested to know... (Score 1) 282

by jsveiga (#32723432) Attached to: iOS Update May Tackle iPhone 4's Antenna Problems

overall network (WCDMA) performance will be degraded for all users in the neighborhood.

Good thing the iPhone uses UMTS.

and UMTS uses WCDMA.

What we are used to call UMTS is GSM + WCDMA (the standard can go farther, but the bread-and-butter is GSM + WCDMA now).

GSM uses TDMA (which is not the "old" TDMA, which technically is called IS-136, and IS-54 when it was part AMPS, part TDMA).

The WCDMA used by UMTS (when your phone is in "3G" or "3.5G") isn't your grandpa's CDMA either, which technically was CDMA2000, and IS-95 before it).

I specifically said WCDMA because it is a characteristic of WCDMA (and CDMA) to be much more sensitive to uplink power control than GSM when it comes to degrading overall network performance - when your UMTS phone in (W)CDMA mode transmits with more power than it needs to, that is "noise" for everyone else's phone signal in the same (W)CDMA carrier trying to reach the cellsite.

That effect is not as relevant when your UMTS phone is in GSM mode, because you are not sharing the same frequency (at the same time) with others near you. In (W)CDMA, many phones share the same frequency at the same time, each one being separated by a XORed code, crudely speaking (black magic involved).

If your phone in GSM transmits with more power than it should, you just get worse battery life (and a remote possibility of interfering with someone using anoter cellsite far away).

If your phone (or a lot of phones) in WCDMA transmits with more power than it should, it hurts network capacity.

Comment: Re:Interested to know... (Score 4, Informative) 282

by jsveiga (#32719652) Attached to: iOS Update May Tackle iPhone 4's Antenna Problems

... the iPhone 4 was designed to look for towers with lower congestion, even if they might have a weaker signal.

That sounds strange. Only while in idle mode (no calls in place) a GSM/UMTS phone has some autonomy to select the cell site to which it will "listen" to.

If the iPhone follows the UMTS standards, while in a call it reports received signal information from neighboring cell sites (or towers) to the network, and the network then decides which cell site(s) the phone will use (or switch to, what is called handoff). The phone has to obey the network's decision, so the only way that the phone software could affect the cell site choices would be to send "fake" (or wrong) received signal information back to the network (which would violate the GSM/UMTS standard).

Comment: Re:Interested to know... (Score 4, Insightful) 282

by jsveiga (#32719450) Attached to: iOS Update May Tackle iPhone 4's Antenna Problems

It won't but it will change the refresh rate of the antenna signal strength meter so you won't notice the signal going down anymore.

...so when the call quality gets bad, you'll be able to blame the network, not Apple.

...and on the transmit side, the software will pump up more average power than what the network power control requests, so your battery life will get worse, and overall network (WCDMA) performance will be degraded for all users in the neighborhood.

He's like a function -- he returns a value, in the form of his opinion. It's up to you to cast it into a void or not. -- Phil Lapsley

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