4 ms·
It's one of those head-smacking why-didn't-anyone-think-of-this-before kinda ideas.
by chaosprophet 17y ago
It's one of those head-smacking why-didn't-anyone-think-of-this-before kinda ideas.
- joezydeco 17y agoCost ($0.50 over 10 million phones adds up) and CPU/DSP power to perform the cancellation.
- jerf 17y agoThe cost of the second microphone can be substantial. The cost of the CPU power may not be. You can get a very long way in noise cancellation simply by placing the two mics near each other and subtracting the signal of one from the other. See the noise-canceling entry of http://en.wikipedia.org/wiki/Microphone#Application-specific_designs http://en.wikipedia.org/wiki/Microphone#Application-specific... (the last paragraph in the "Application-specific designs). You don't even need a CPU for that, you can do that with simple electronics. Noise-canceling headphones are freakishly complicated, directional (what is often meant by "noise canceling") microphones are possible with very simple designs. I wish I could google up a piece on signal processing but my google search is getting dominated by things I can buy.
- invisible 17y agoDid you try "Show Options" on the results bar? Then choose "Fewer shopping sites." Worth a shot.
- mbrubeck 17y agoIt's a fairly common feature, for example there are several bluetooth headsets on the market with dual mics for noise reduction.
- jrockway 17y agoBut zero actual phones, until this one.
- camccann 17y agoSee here: http://en.wikipedia.org/wiki/Active_noise_control http://en.wikipedia.org/wiki/Active_noise_control The basic idea of dual microphones to filter background from signal is pretty common.