An intra-body network system, comprising: a first implantable medical device comprising a first communication circuitry; and a second implantable medical device comprising a second communication circuitry; wherein the first communication circuitry and the second communication circuitry are configured to establish, in an implanted state of the first implantable medical device and the second implantable medical device, a communication for transmitting a communication signal from at least one of the first implantable medical device to the second implantable medical device and from the second implantable medical device to the first implantable medical device; wherein at least one of the first implantable medical device and the second implantable medical device comprises an antenna arrangement configured to at least one of transmit and receive a communication signal in a first configuration state using a first directive radiation characteristic, in a second configuration state using a second directive radiation characteristic different from the first directive radiation characteristic and a third configuration state using a third directive radiation characteristic different from the first directive radiation characteristic and the second directive radiation characteristic, and wherein at least one of the first communication circuitry and the second communication circuitry is configured, in an initialization phase, to at least one of transmit and receive a communication signal using the first configuration state, the second configuration state and the third configuration state of the antenna arrangement in order to select a configuration state out of the first configuration state, the second configuration state and the third configuration state and, in an operational state, to use the selected configuration state for communication. a first implantable medical device comprising a first communication circuitry; and a second implantable medical device comprising a second communication circuitry; wherein the first communication circuitry and the second communication circuitry are configured to establish, in an implanted state of the first implantable medical device and the second implantable medical device, a communication for transmitting a communication signal from at least one of the first implantable medical device to the second implantable medical device and from the second implantable medical device to the first implantable medical device; wherein at least one of the first implantable medical device and the second implantable medical device comprises an antenna arrangement configured to at least one of transmit and receive a communication signal in a first configuration state using a first directive radiation characteristic, in a second configuration state using a second directive radiation characteristic different from the first directive radiation characteristic and a third configuration state using a third directive radiation characteristic different from the first directive radiation characteristic and the second directive radiation characteristic, and wherein at least one of the first communication circuitry and the second communication circuitry is configured, in an initialization phase, to at least one of transmit and receive a communication signal using the first configuration state, the second configuration state and the third configuration state of the antenna arrangement in order to select a configuration state out of the first configuration state, the second configuration state and the third configuration state and, in an operational state, to use the selected configuration state for communication.