An apparatus for duplexing signals to be transmitted wirelessly and signals received wirelessly by an antenna, comprising: a hybrid junction comprising an antenna node for coupling to the antenna, an input node for receiving a signal to be transmitted by the antenna, an output node for outputting a signal received wirelessly by the antenna, and a balancing node; a variable impedance coupled to the balancing node; and a controller arranged to: a) set the variable impedance to an impedance setting; b) transmit a first transmit signal at a first transmit frequency in a first frequency band of interest; c) measure a first signal at the output node at a first receive frequency in a second frequency band of interest as a result of the first signal transmitted at the first transmit frequency; d) select another impedance setting of the variable impedance e) transmit a second transmit signal at a second transmit frequency in the first frequency band of interest; f) measure a second signal at the output node at a second receive frequency in the second frequency band of interest as a result of the second signal transmitted at the second transmit frequency; g) employing a system of equations comprising variables associating the first measured signal, the second measured signal, the first impedance setting, and the second impedance setting; and h) solving the system of equations to determine an impedance setting that substantially results in isolation between the input node and the output node of the hybrid junction. a hybrid junction comprising an antenna node for coupling to the antenna, an input node for receiving a signal to be transmitted by the antenna, an output node for outputting a signal received wirelessly by the antenna, and a balancing node; a variable impedance coupled to the balancing node; and a controller arranged to: a) set the variable impedance to an impedance setting; b) transmit a first transmit signal at a first transmit frequency in a first frequency band of interest; c) measure a first signal at the output node at a first receive frequency in a second frequency band of interest as a result of the first signal transmitted at the first transmit frequency; d) select another impedance setting of the variable impedance e) transmit a second transmit signal at a second transmit frequency in the first frequency band of interest; f) measure a second signal at the output node at a second receive frequency in the second frequency band of interest as a result of the second signal transmitted at the second transmit frequency; g) employing a system of equations comprising variables associating the first measured signal, the second measured signal, the first impedance setting, and the second impedance setting; and h) solving the system of equations to determine an impedance setting that substantially results in isolation between the input node and the output node of the hybrid junction. a) set the variable impedance to an impedance setting; b) transmit a first transmit signal at a first transmit frequency in a first frequency band of interest; c) measure a first signal at the output node at a first receive frequency in a second frequency band of interest as a result of the first signal transmitted at the first transmit frequency; d) select another impedance setting of the variable impedance e) transmit a second transmit signal at a second transmit frequency in the first frequency band of interest; f) measure a second signal at the output node at a second receive frequency in the second frequency band of interest as a result of the second signal transmitted at the second transmit frequency; g) employing a system of equations comprising variables associating the first measured signal, the second measured signal, the first impedance setting, and the second impedance setting; and h) solving the system of equations to determine an impedance setting that substantially results in isolation between the input node and the output node of the hybrid junction.