4 ms·
Its a question of terminology. When you are passively listening to (periodic) SSID beacons, you are not transmitting anything, nor consuming any energy on your
by sly010 10y ago
Its a question of terminology. When you are passively listening to (periodic) SSID beacons, you are not transmitting anything, nor consuming any energy on your radio. One could do that even in airplane mode.
It's very different from when you hit "scan" and are actively sending broadcast packets on every frequency and waiting for the wifi routers to (actively) answer. Which really only happens when you pull down the list of nearby hotspots.
- mirashii 10y ago> nor consuming any energy on your radio This simply isn't true. You'll be using power to demodulate at a minimum. You'll also be using energy to ammplify the incoming signals and a variety of other things.
- klodolph 10y agoYes, this is also the reason why GPS is so power hungry--it takes a lot of power to keep a GPS radio receiver operating.
- jsjohnst 10y agoClose enough for a quick reply, but it's not the "radio" using lots of power, it's the chip that's doing the signal processing. GPS signals are very weak (approximately -120dbm) and thus below the noise floor. It takes complex FFT operations that actually cause the power hungry nature to find the proverbial needle in the haystack.
- klodolph 10y agoNormally, "radio" includes the amplifiers and demodulators, even if they're digital.
- jhayward 10y ago> or consuming any energy on your radio Listening is actually one of the more power-intensive things a radio does, because it tends to be active more of the time than transmitting does. For many radios power consumption is the same whether transmitting or receiving.