Functional neuromuscular stimulation system

A system for transcutaneously telemetering position signals out of a human body and for controlling a functional electrical stimulator implanted in said human body, said system comprising:

• an implantable radio frequency receiving coil for receiving a transcutaneous radio frequency signal;
• an implantable power supply connected to said radio frequency receiving coil, said power supply converting received transcutaneous radio frequency signals into electromotive power;
• an implantable input signal generator electrically powered by said implantable power supply for generating at least one analog input movement signal to indicate voluntary bodily movement along an axis;
• an implantable encoder having an input operatively connected with said implantable input signal generator for encoding said movement signal into output data in a preselected data format;
• an impedance altering means connected with said encoder and said implantable radio frequency signal receiving coil to selectively change an impedance of said implantable radio frequency signal receiving coil;
• an external radio frequency signal transmit coil inductively coupled with said implantable radio frequency signal receiving coil, such that impedance changes in said implantable radio frequency signal receiving coil are sensed by said external radio frequency signal transmit coil to establish a sensed modulated movement signal in said external transmit coil;
• an external control system electrically connected to said external radio frequency transmit coil for monitoring said sensed modulated movement signal in said external radio frequency transmit coil, said external control system including:
• a demodulator for recovering the output data of said encoder from the sensed modulated movement signal of said external transmit coil,
• a pulse width algorithm means for applying a preselected pulse width algorithm to the recovered output data to derive a first pulse width,
• an amplitude algorithm means for applying an amplitude algorithm to the recovered output data to derive a first amplitude therefrom,
• an interpulse interval algorithm means for applying an interpulse algorithm to the recovered output data to derive a first interpulse interval therefrom;
• and,
• a stimulation pulse train signal generator for generating a stimulus pulse train signal which has the first pulse width and the first pulse amplitude;
• an implantable functional electrical stimulator for receiving said stimulation pulse train signal from said stimulation pulse train signal generator and generating stimulation pulses with the first pulse width, the first pulse amplitude, and separated by the first interpulse interval;
• and,
• at least one electrode operatively connected with the functional electrical stimulator for applying said stimulation pulses to muscle tissue of said human body.