Re: [Starlink] SpaceX/Starlink says it's ready for a fall satellite-to-cell service with T-Mobile

[David Lang <david@lang.hm>]

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Eugene Y Chang wrote:

>> On Jun 3, 2024, at 12:41 PM, David Lang <david@lang.hm> wrote:
>>
>> Eugene Y Chang wrote:
>>
>>> I expect low data rate because the distance will fall back to a lower coding rate.
>>
>> I think it's going to be more a matter of very large cells, so many people sharing the available bandwidth
>>
>>> I observe a difference in my phone’s batter life between urban and rural usage. I expect the battery life to be significantly reduced with Starlink.
>>> And yes… if the phone isn’t communicating then the battery life isn’t drawn down much…
>>
>> In my experience, a phone that's trying to find a tower uses more power than one that has a tower, but is otherwise idle
>
> When the phone is searching for a tower, it is transmitting at maximum power.
> Then, the phone adjusts the transmit power according to the distance to the tower,
> In an urban environment, the distance to the tower is usually less (i.e. smaller cells due to subscriber density).
> In a rural environment, there is more distance to the tower, and the phone is transmitting at higher power (i.e., towers are farther apart for larger cells due to fewer subscribers per tower, up to the max tower separation.)
> When you are mobile, the power is proportionate to the mean distance to the tower during your operations.

and for direct-to-satellite, it's going to be a max power situation, similar to 
rural.

But when a phone is not connected, how frequent are it's searches for towers 
(especially if it has multiple bands to check) compared to the 'keepalive' pings 
when it is connected? if it's doing more transmissions for it's search and 
attempts to connect than it does while connected and just confirming the 
connection, that could eat more power.

David Lang