Receiver and transmitter receiver system

A transmitter receiver system, comprising:

• a transmitter configured to generate a message for the receiver by modulating its current consumption;
• and
• a receiver comprising:
• a controller;
• and
• a driver stage configured to provide a supply voltage to the transmitter based on a control signal;
• wherein the controller is configured to measure the supply voltage and to provide the control signal to compensate for changes of the supply voltage caused by a modulation of the current consumption of the transmitter, such that the supply voltage remains in a predefined range;
• and
• wherein the controller is further configured to evaluate a series of succeeding values of the control signal to derive a message generated by the transmitter by modulating its current consumption.

A method for receiving messages from a transmitter, the method comprising:

• providing a supply voltage to the transmitter based on a control signal;
• measuring the supply voltage;
• providing the control signal to compensate changes of the supply voltage caused by a modulation of the current consumption of the transmitter, such that the supply voltage remains in a predetermined range;
• and
• evaluating a series of succeeding values of the control signal to derive a message generated by the transmitter by modulating its current consumption.

A receiver for receiving messages from a transmitter, the receiver comprising:

• a controller;
• and
• a driver stage configured to provide a supply voltage to the transmitter based on a control signal;
• wherein the controller is configured to measure the supply voltage and to provide the control signal to compensate for changes of the supply voltage caused by a modulation of the current consumption of the transmitter, such that the supply voltage remains in a predefined range;
• wherein the controller comprises a comparator configured to obtain a digital representation of the supply voltage provided by the driver stage;
• wherein the controller is configured to evaluate the digital representation of the supply voltage to adjust the control signal;
• and
• wherein the controller is configured to evaluate a series of succeeding values of the control signal using a digital model of the driver stage to estimate a supply current of the transmitter to derive a message generated by the transmitter by modulating its current consumption;
• wherein the controller is configured to interpret a rising or falling slope of the current consumption of the transmitter as an information unit of the message generated by the transmitter;
• wherein the controller is configured to interpret a decrease or an increase in the current consumption of the transmitter as a falling slope or a rising slope of the current consumption if a difference between a value of the control signal before the decrease or increase of the current consumption and a value of the control signal for compensating the decrease or increase in current consumption is above a given threshold;
• wherein the driver stage comprises a current mirror and a current steering DAC;
• wherein the current steering DAC is configured to adjust a first output current from a first input terminal to a first output terminal of the current mirror, based on the control signal;
• wherein the current mirror is configured to mirror the first output current, such that a second output current of the current mirror from a second input terminal to a second output terminal of the current mirror follows the first output current of the current mirror;
• wherein a supply current for the transmitter is based on the second output current of the current mirror;
• wherein the current steering DAC comprises a first current steering terminal being coupled to the first output terminal of the current mirror, for steering the first output current of the current mirror;
• and
• wherein the second output current of the current mirror is divided into a first component and a second component;
• wherein the current steering DAC comprises a second current steering terminal being coupled to the second output terminal of the current mirror, and is configured to steer the supply voltage of the transmitter by sinking the first component of the second output current into the second current steering terminal;
• wherein driver stage is configured to provide the second component of the second output current is provided as the supply current of the transmitter;
• wherein the controller is configured to provide upon a detection of a decrease of the supply voltage caused by an increased current consumption of the transmitter the control signal, such that the first output current of the current mirror is increased and the first component of the output current of the current mirror sinking into the second current steering terminal of the current steering DAC is decreased;
• and
• wherein the controller is configured to provide, upon a detection of an increase of the supply voltage caused by a decreased current consumption of the transmitter, the control signal, such that the first output current of the current mirror is decreased and the first component of the output current of the current mirror sinking into the second current steering terminal of the current steering DAC is increased.