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To: LeGrande
This is off topic, unless you are alleging that the IPhone 4 isn't transmitting properly. Are you? Do you have any data?

No, and I did not allege that. Total channel performance of a duplex communications channel is a combination of the TX and RX; assuming TX is the same, then RX becomes the dominant factor for SNR. And if you have weak RX you can compensate by higher TX (since TX+RX is your total channel performance).

"so it's readily apparent that the new baseband hardware is much more sensitive compared to what was in the 3GS. The difference is that reception is massively better on the iPhone 4 in actual use.

This conclusion is not logical, by the article writer. Sensitivity is NOT concluded to be higher, only that total channel performance is higher, and that noise cancellation and audio signal processing allow for the iPhone 4 to produce higher quality audio with weaker signals. Improved sensitivity is not required to generate the data the author reports.

With typical cell phones, when the signal is below -100 dBm then the phone tries to switch to a new cell; it may be that the new iPhone does not, and maintains its connection because of other processing in the phone. That will reduce audio effects due to switching, but at the cost of higher noise in the channel (reduced SNR), which can be ameliorated with improved noise gating and dynamic bandwidth limitation (something I've used many times in phone conferencing systems).

Or, you can crank up your TX level to full strength (something that is rarely done) to compensate as well. This results in increased battery power consumption, which is also being reported in some iPhones.

Knowing how total channel performance is a combination of TX and RX, you can compensate for some loss in RX performance by increasing TX output. And that may be what is happening with the iPhone 4, and provides some improvement in total performance.

There is nothing taken out of context, and I thought for someone with some RF background and an EE degree this would be pretty obvious. The relation of these facts and surmising should be obvious for most EEs.

72 posted on 07/03/2010 8:43:11 PM PDT by PugetSoundSoldier (Indignation over the Sting of Truth is the defense of the indefensible)
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To: PugetSoundSoldier
No, and I did not allege that. Total channel performance of a duplex communications channel is a combination of the TX and RX;

So then are you alleging total channel performance is impaired? Again what are your stats?

This conclusion is not logical, by the article writer. Sensitivity is NOT concluded to be higher, only that total channel performance is higher,

Ahh, so you agree that total channel performance is higher then? Those are your words aren't they?

Or, you can crank up your TX level to full strength (something that is rarely done) to compensate as well. This results in increased battery power consumption, which is also being reported in some iPhones.

Are you alleging that the IPhone has cranked up the TX? That is very easy to test. Do you have the data to back your claim?

Knowing how total channel performance is a combination of TX and RX, you can compensate for some loss in RX performance by increasing TX output. And that may be what is happening with the iPhone 4, and provides some improvement in total performance.

Again do you have any data to support that claim? Or are you being intentionally noncommittal? Words like 'may' are weasel words.

There is nothing taken out of context, and I thought for someone with some RF background and an EE degree this would be pretty obvious. The relation of these facts and surmising should be obvious for most EEs.

Nothing taken out of context? You haven't even clearly stated what you think is happening.

Please clearly state what you think is happening with evidence to back it up. I would really like to see APPLES to APPLES comparisons. Specifically on TX and RX values.

73 posted on 07/03/2010 11:00:20 PM PDT by LeGrande (Yes, I am an agent of Satan, but my duties are largely ceremonial.)
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