Wireless headphones: for home & on the go
In the case of wireless headphones, the modulating signal is the audio sign supposed for the headphone drivers.
There are several approaches that the modulating sign may additionally modulate the carrier wave.
Wireless Analog Audio Transmission
For wireless analog audio sign transmission to headphones, it’s far frequency modulation this is most not unusual.
Yes, the same transmission is used in FM radio, cordless headset which basically makes our RF FM headphones like a mini radio station!
Frequency modulation (FM) works through having the modulating sign modulate the frequency of the service wave. If we had been to ship a simple audio sine wave, the ensuing frequency modulated sign might resemble some thing like this:
To hold the version in the service wave frequency low and concise, the audio signal is handiest amplified once the headphones receiver demodulates it.
Headphone audio alerts are almost constantly stereo. Fortunately, FM provider signals can be used to hold stereo audio. This is achieved with multiplexing and demultiplexing before and after the frequency modulation procedure.
Multiplexing is effectively the combination of multiple mono indicators or stereo signals being mixed into a single signal.
With right multiplexing and demultiplexing, the real FM modulation and demodulation approaches are identical in stereo and mono processes.
Wireless Digital Audio Transmission
With the rise of digital audio and digital audio devices, many headphones are now designed to accept digital audio wirelessly.
Digital audio is basically a virtual illustration of analog audio.
Analog audio is made up of continuous waves of alternating modern-day. Digital audio basically takes immediate snapshots of the amplitude of the audio sign and represents them digitally.
The satisfactory of digital audio may be defined by its pattern price and bit-intensity.
Sample rate refers to how many man or woman audio amplitudes are sampled every 2nd. Common sample charges encompass 44.1 kHz and forty eight kHz. In this case, Hz refers to samples/second.
The bit-intensity refers to how many bits are used to represent the amplitude of any given pattern. Bits seek advice from the variety of binary digits (1s and 0s) chained together to represent a fee. Common bit-depths include sixteen-bit (which has sixty five,536 awesome values) and 24-bit (which has sixteen,777,215 distinct values).
