Implantable medical device

An external device comprising:

• a second bidirectional wireless interface configured to transmit data via an alternating electromagnetic field between the external device and an implantable medical device;
• and,
• an inductive transmission unit configured to transmit a data transmission start signal to the implantable medical device via an alternating magnetic field to unidirectionally communicate with said implantable medical device without receipt of information over said inductive transmission unit to implement a unidirectional inductive activation mechanism;
• wherein the implantable medical device comprises
• a bidirectional wireless interface;
• a magnetic interface configured to activate said bidirectional wireless interface via a unidirectional inductive activation mechanism;
• and
• a control unit connected to the bidirectional wireless interface;
• wherein the control unit is further connected to the magnetic interface,
• wherein the magnetic interface or the control unit is configured to generate the wireless interface activation signal after the data transmission start signal is received only if the data transmission start signal received via the magnetic interface contains a device-specific identifier for a specific implantable medical device, and,
• wherein the magnetic interface is further configured to receive a data transmission start signal and to process the data transmission start signal such, that the magnetic interface or the control unit generates a wireless interface activation signal in response to reception of the data transmission start signal;
• wherein the external device is configured to assign a response time to the data transmission start signal;
• and,
• wherein the implantable medical device is configured to
• extract a response time identifier from the data transmission start signal identifying the response time, wherein the response time is a point in time at which the implantable device generates the wireless interface activation signal;
• extract the device-specific identifier;
• and,
• generate the wireless interface activation signal only when the response time defined by the response time identifier has been reached.

A method for initiating a bidirectional data transmission between an implantable medical device having a magnetic interface and a first wireless interface and an external device having an inductive transmission unit and a second wireless interface, comprising

• transmitting a data transmission start signal from the inductive transmission unit to the magnetic interface wherein said data transmission signal comprises a wireless channel identifier that controls a channel utilized by said first wireless interface;
• and,
• switching the first wireless interface in the implantable medical device to an activated state;
• wherein the external device is configured to assign a response time to the data transmission start signal;
• and,
• wherein the implantable medical device is configured to
• extract a response time identifier from the data transmission start signal identifying the response time, wherein the response time is a point in time at which the implantable device generates the wireless interface activation signal;
• extract the device-specific identifier;
• and,
• generate the wireless interface activation signal only when the response time defined by the response time identifier has been reached.