android PPM audio library

I need to implement audio PPM (Pulse Position Modulation) on android

Reference: http://ift.tt/PdoAGi

I want to output PPM from the audio output of the smartphone. The final scope is to create a joystick for radiocontrol. but this library may have many future purposes (follow me, lightbridge, etc.etc.). The radios commonly have a PPM output. Transmitters (and pc flight simulators) commonly have PPM input. My scope is to replace the radio with an android device. I wish to know if there is some piece of code ready to use or should i start from scratch?

EDIT: I found some points where to start

1) smartpropplus is a windows software that receives PPM audio and decodes it http://ift.tt/1OTf5vR

2) this is how PPM is structured: http://ift.tt/1DSNF5u

3) this is a easy image that explains how the signal is structured: http://ift.tt/1DSNF5w

I calculated that sampling the audio signal at 22000Hz will be sufficient to achieve a good resolution for each channel (22 steps for each channel)