초록 ▼

There is provided an improved telemetry system for use with implantable devices such as cardiac pacemakers and the like, for two-way telemetry between the implanted device and an external programmer. The system employs highly energy efficient oscillators with encoding circuits for synchronous transm

There is provided an improved telemetry system for use with implantable devices such as cardiac pacemakers and the like, for two-way telemetry between the implanted device and an external programmer. The system employs highly energy efficient oscillators with encoding circuits for synchronous transmission of data symbols, which symbols form the telemetry carrier. The system provides improved circuits for higher density data encoding of sinusoidal symbols, including improved combinations of BPSK, FSK, and ASK encoding. Embodiments of transmitters for both the implanted device and the external programmer, as well as modulator and demodulator circuits, are also disclosed, and specifically include oscillators which switch capacitors between a tank circuit and a recharge path, the switching being controlled to occur at moments of substantially zero coil current, thereby providing high efficiency operation.

대표청구항 ▼

[ What is claimed is:] [1.] In an implantable device, a transmitter for generating a telemetry signal which is made up of sinusoidal symbols, comprisingoscillator means for generating sinusoidal symbols, said oscillator having a high Q coil for transmitting said telemetry signal;a source of data sig

[ What is claimed is:] [1.] In an implantable device, a transmitter for generating a telemetry signal which is made up of sinusoidal symbols, comprisingoscillator means for generating sinusoidal symbols, said oscillator having a high Q coil for transmitting said telemetry signal;a source of data signals; andencoding means connected to receive said data signals, for encoding each of said symbols with a combination of BPSK, FSK and ASK data in accord with said data signals.