On Wed, 21 Dec 2005, Howard Winter wrote:

> Peter,
>
> On Sun, 18 Dec 2005 23:47:25 +0200 (IST), Peter wrote:
>
>>
>> On Sun, 18 Dec 2005, Howard Winter wrote:
>>
>>> And having achieved the saving in power to produce the picture, they
>>> are then talking about using radio to transmit it!  Isn't that a bit
>>> like striving to reduce the weight of the label on a hammer handle?
>>> :-)
>>
>> Most contemporary cameras have WiFi connection for picture
>> copying/printing.
>
> I don't know if you are talking about photographic-type uses, but the 
> item I was talking about was for security cameras - which presumably 
> transmit images at quite a high rate, perhaps once a second or more. 
> That really doesn't sound like a battery application to me.

Current WiFi 'security' cameras use most of the power to run the ARM cpu 
that runs the web server afaik ;-). The radio is limited to 10mW maximum 
anyway and it actually consumes much less when used in bursts. I think 
that a camera that uses 1mW or less an sends one picture per second is 
realistic if the processing is done by the imaging element itself 
(perhaps by broadcasting picture data using a new format). That would be 
about 300uA at 3V. It could run for two months on a 2Ah lithium battery.

Peter
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