An apparatus comprising: a radio frequency, RF, antenna circuit; an antenna aperture tuning circuit (310, 410); an antenna impedance measurement circuit; and a processor circuit electrically coupled to the antenna aperture tuning circuit (310, 410) and the antenna impedance measurement circuit, wherein the processor circuit is configured to: set the antenna aperture tuning circuit (310, 410) to an antenna aperture tuning state according to one or more parameters of an RF communication network; initiate an antenna impedance measurement to obtain an antenna impedance; adjust the antenna aperture tuning state as a function of the antenna impedance, the apparatus further including an impedance matching circuit electrically coupled to the RF antenna circuit, wherein the processor circuit is configured to change impedance of the impedance matching circuit to change transducer gain of the RF antenna circuit when the antenna aperture tuning state is adjusted to the antenna aperture tuning state as a function of the antenna impedance, wherein the antenna impedance measurement circuit is configured to determine magnitude and phase of a forward signal and a reverse signal of a transmit signal, and wherein the processor circuit is configured to determine the antenna impedance measurement using a difference in phase between the forward signal and the reverse signal, and a ratio including the magnitudes of the forward signal and the reverse signals; characterized in that the processor circuit is further configured to adjust the antenna aperture tuning state by selecting an antenna aperture tuning state using a lookup table that includes antenna aperture tuning states indexed according to antenna impedance, and setting the antenna aperture tuning state to the selected antenna aperture tuning state, wherein the lookup table maps a present tuning state and the determined antenna impedance to a desired tuning state. a radio frequency, RF, antenna circuit; an antenna aperture tuning circuit (310, 410); an antenna impedance measurement circuit; and a processor circuit electrically coupled to the antenna aperture tuning circuit (310, 410) and the antenna impedance measurement circuit, wherein the processor circuit is configured to: set the antenna aperture tuning circuit (310, 410) to an antenna aperture tuning state according to one or more parameters of an RF communication network; initiate an antenna impedance measurement to obtain an antenna impedance; adjust the antenna aperture tuning state as a function of the antenna impedance, the apparatus further including an impedance matching circuit electrically coupled to the RF antenna circuit, wherein the processor circuit is configured to change impedance of the impedance matching circuit to change transducer gain of the RF antenna circuit when the antenna aperture tuning state is adjusted to the antenna aperture tuning state as a function of the antenna impedance, wherein the antenna impedance measurement circuit is configured to determine magnitude and phase of a forward signal and a reverse signal of a transmit signal, and wherein the processor circuit is configured to determine the antenna impedance measurement using a difference in phase between the forward signal and the reverse signal, and a ratio including the magnitudes of the forward signal and the reverse signals; characterized in that the processor circuit is further configured to adjust the antenna aperture tuning state by selecting an antenna aperture tuning state using a lookup table that includes antenna aperture tuning states indexed according to antenna impedance, and setting the antenna aperture tuning state to the selected antenna aperture tuning state, wherein the lookup table maps a present tuning state and the determined antenna impedance to a desired tuning state. set the antenna aperture tuning circuit (310, 410) to an antenna aperture tuning state according to one or more parameters of an RF communication network; initiate an antenna impedance measurement to obtain an antenna impedance; adjust the antenna aperture tuning state as a function of the antenna impedance, the apparatus further including an impedance matching circuit electrically coupled to the RF antenna circuit, wherein the processor circuit is configured to change impedance of the impedance matching circuit to change transducer gain of the RF antenna circuit when the antenna aperture tuning state is adjusted to the antenna aperture tuning state as a function of the antenna impedance, wherein the antenna impedance measurement circuit is configured to determine magnitude and phase of a forward signal and a reverse signal of a transmit signal, and wherein the processor circuit is configured to determine the antenna impedance measurement using a difference in phase between the forward signal and the reverse signal, and a ratio including the magnitudes of the forward signal and the reverse signals; characterized in that the processor circuit is further configured to adjust the antenna aperture tuning state by selecting an antenna aperture tuning state using a lookup table that includes antenna aperture tuning states indexed according to antenna impedance, and setting the antenna aperture tuning state to the selected antenna aperture tuning state, wherein the lookup table maps a present tuning state and the determined antenna impedance to a desired tuning state.