An RF telemetry receiver circuit for active implantable medical devices. The baseband binary signal (D.sub.b) is doubly modulated by a low frequency carrier (F.sub.m) and by a high frequency carrier (F.sub.c). The receiver circuit is a semi-passive non heterodyne circuit, devoid of a local oscillator and mixer. It comprises an antenna (104), a passive bandpass filter (108) centered on the high-frequency carrier (F.sub.c), a passive envelope detector (120-126) and a digital demodulator (116). The envelope detector comprises a first diode circuit (120) of non-coherent detection, an active bandpass filter (122) centered on a frequency (2.F.sub.m) twice the low frequency carrier and having a bandwidth (2.D.sub.b) twice the baseband bandwidth, and a second diode circuit (124) of non-coherent detection, outputting a baseband signal applied to the digital demodulation stage (116).

An RF telemetry receiver circuit for active implantable medical devices. The baseband binary signal (D.sub.b) is doubly modulated by a low frequency carrier (F.sub.m) and by a high frequency carrier (F.sub.c). The receiver circuit is a semi-passive non heterodyne circuit, devoid of a local oscillator and mixer. It comprises an antenna (104), a passive bandpass filter (108) centered on the high-frequency carrier (F.sub.c), a passive envelope detector (120-126) and a digital demodulator (116). The envelope detector comprises a first diode circuit (120) of non-coherent detection, an active bandpass filter (122) centered on a frequency (2.F.sub.m) twice the low frequency carrier and having a bandwidth (2.D.sub.b) twice the baseband bandwidth, and a second diode circuit (124) of non-coherent detection, outputting a baseband signal applied to the digital demodulation stage (116).

A radio frequency, RF, transmitter, comprises a digitally controlled oscillator, DCO, configured to generate an RF signal; and digital modulation circuitry connected to the DCO for modulation of the RF signal, and driven by an RF clock signal derived from the RF signal, wherein the digital modulation circuitry comprises a module configured to apply a compensation for modulation jitter due to the modulation circuitry being driven by the RF clock signal and a compensation for DCO non-linearity.

A radio frequency, RF, transmitter, comprises a digitally controlled oscillator, DCO, configured to generate an RF signal; and digital modulation circuitry connected to the DCO for modulation of the RF signal, and driven by an RF clock signal derived from the RF signal, wherein the digital modulation circuitry comprises a module configured to apply a compensation for modulation jitter due to the modulation circuitry being driven by the RF clock signal and a compensation for DCO non-linearity.

The present embodiments are directed to a device for generating radio frequency signals, including high power radio frequency signals. In certain embodiments, the device comprises multiple transmission lines driven in parallel at their input and connected in series at their output. The electromagnetic transit lengths of the transmission lines may be unequal. A series connection of the transmission lines at the output may produce an output signal from each transmission line driving the same polarity signal to the load. The series connection of transmission lines at the output may produce a bipolar output signal. One section of the device may convert a unipolar input signal into a bipolar signal. One section of the device may duplicate the input signal. Multiple sections may be arranged to convert a unipolar input signal into multiple radio frequency oscillations.

The present embodiments are directed to a device for generating radio frequency signals, including high power radio frequency signals. In certain embodiments, the device comprises multiple transmission lines driven in parallel at their input and connected in series at their output. The electromagnetic transit lengths of the transmission lines may be unequal. A series connection of the transmission lines at the output may produce an output signal from each transmission line driving the same polarity signal to the load. The series connection of transmission lines at the output may produce a bipolar output signal. One section of the device may convert a unipolar input signal into a bipolar signal. One section of the device may duplicate the input signal. Multiple sections may be arranged to convert a unipolar input signal into multiple radio frequency oscillations.

A logarithmic detector amplifying (LDA) system is provided for use as a high sensitivity receive booster or replacement for a low noise amplifier in a receive chain of a communication device. The LDA system may include an amplifying circuit configured to receive an input signal having a first frequency and generate an oscillation based on the input signal, a sampling circuit coupled to the amplifying circuit and configured to terminate the oscillation based on a predetermined threshold to generate a series of modulated pulses, and one or more resonant circuits including at least one variable capacitor, coupled with the amplifying circuit and configured to establish a frequency of operation and generate an output signal having a second frequency being substantially the same as the first frequency, with the operating frequency being adjustable in response to baseband information received from the system via the one or more variable capacitors.

A logarithmic detector amplifying (LDA) system is provided for use as a high sensitivity receive booster or replacement for a low noise amplifier in a receive chain of a communication device. The LDA system may include an amplifying circuit configured to receive an input signal having a first frequency and generate an oscillation based on the input signal, a sampling circuit coupled to the amplifying circuit and configured to terminate the oscillation based on a predetermined threshold to generate a series of modulated pulses, and one or more resonant circuits including at least one variable capacitor, coupled with the amplifying circuit and configured to establish a frequency of operation and generate an output signal having a second frequency being substantially the same as the first frequency, with the operating frequency being adjustable in response to baseband information received from the system via the one or more variable capacitors.

The present embodiments are directed to a device for generating radio frequency signals, including high power radio frequency signals. In certain embodiments, the device comprises multiple transmission lines driven in parallel at their input and connected in series at their output. The electromagnetic transit lengths of the transmission lines may be unequal. A series connection of the transmission lines at the output may produce an output signal from each transmission line driving the same polarity signal to the load. The series connection of transmission lines at the output may produce a bipolar output signal. One section of the device may convert a unipolar input signal into a bipolar signal. One section of the device may duplicate the input signal. Multiple sections may be arranged to convert a unipolar input signal into multiple radio frequency oscillations.

The present embodiments are directed to a device for generating radio frequency signals, including high power radio frequency signals. In certain embodiments, the device comprises multiple transmission lines driven in parallel at their input and connected in series at their output. The electromagnetic transit lengths of the transmission lines may be unequal. A series connection of the transmission lines at the output may produce an output signal from each transmission line driving the same polarity signal to the load. The series connection of transmission lines at the output may produce a bipolar output signal. One section of the device may convert a unipolar input signal into a bipolar signal. One section of the device may duplicate the input signal. Multiple sections may be arranged to convert a unipolar input signal into multiple radio frequency oscillations.