**4. Single step antenna tuning unit**

To address the problem due to impedance mismatch, many antenna impedance tuning units operating iteratively and/or using directional coupler to evaluate the quality of the link were investigated [7-15]. Since the use of a bulky additional coupler into the device is totally inacceptable and since iterative matching process spends time and consumes power to set the proper state of the network, we investigate on a novel coupler less method [25] solving the problems related to the impedance mismatch in a single iteration. The proposed solution detailed in this section is the first system able to match automatically in a single process both TX and RX matching networks. It reduces the power losses in transmission and in reception contributing to the optimization of the power efficiency of the transceiver itself.
