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The title is self-explanative. This is an emprically contrasted fact for cell phones, although I don't know why this happens.

As far as my understanding goes the signal receiver is a passive component. Then, why does it affect battery so drastically?

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    \$\begingroup\$ Your assumption is very wrong. The receiver is an active circuit. It has an LNA, ADC and lots of DSP. \$\endgroup\$
    – Mike
    May 19, 2017 at 5:17
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    \$\begingroup\$ The new "Android O" operating system helps here. Applications that are in the background asking for gps data are now handed old data and do not cause a re-activation of the receiver systems. The application must be moved to the foreground in order for it to cause re-activation of the hardware systems. Prior editions (and some other operating systems) activate the hardware every time the application asks for gps data. Receivers are very heavy battery users. When I was working on the Seiko message watch (years ago), it was the receiver that was the major energy hog. \$\endgroup\$
    – jonk
    May 19, 2017 at 5:37
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    \$\begingroup\$ @ArnoldFrenzy No, I don't know of one. \$\endgroup\$
    – jonk
    May 19, 2017 at 5:45
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    \$\begingroup\$ As far as my understanding goes the signal receiver is a passive component Whoa, who gave you this bit of mis information ? The antenna is passive, maybe that is what you mean. But an antenna alone is pretty useless unless you feed the received signal to a receiver circuit for amplification and further processing. \$\endgroup\$
    – Bimpelrekkie
    May 19, 2017 at 7:34
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    \$\begingroup\$ It's not so much the recieving as the processing needed to understand GPS; the signal is extremely weak and a lot of number-crunching needs to be applied to extract it from the noise and correlate the four or more satellites involved. \$\endgroup\$
    – pjc50
    May 19, 2017 at 8:28

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Receivers are very much active devices that require energy to operate.

Modern Bluetooth receivers require very little energy to operate in receive mode. They should usually use a small percentage of the energy used by a cellphone in typical use.

GPS can use a significant percentage of total energy used.
Active GPS tracking is a high energy application. A GPS receiver is more complex than either broadcast, FM band or even cell-phone band equipment. Energy use does not directly scale with complexity (fortunately) but a GPS receiver needs to receive multiple satellite signals simultaneously and analyse the results to produce position, velocity time and other outputs.

A good idea of relative energy use can be obtained from your phone's records. In Samsung Android 5.x see "settings - more - battery"

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