Standing wave ratio meter for integrated antenna tuner

A method of measuring a peak-to-peak voltages (Vpp) of an RF signal at various locations on an artificial transmission line between a transmitter and an antenna of a wireless communication device;

• the method comprising:
• providing an RF transmit signal to an RF input of the artificial transmission line wherein the artificial transmission line comprises a plurality of LC delay blocks connected in series with a plurality of nodes such that a node is located on either side of each LC delay;
• setting a first variable attenuator, connected to a first node of the plurality of nodes, to attenuate a first node voltage by a first stepped amount and providing a first attenuated voltage;
• detecting the first attenuated voltage by a first detector and providing a first detector output, the first detector output being either zero or a voltage relative to the first attenuated voltage;
• setting a second variable attenuator, connected to a second node of the plurality of nodes, to attenuate a second node voltage by a second stepped amount and providing a second attenuated voltage;
• detecting the second attenuated voltage by a second detector and providing a second detector output, the second detector output being either zero or a voltage relative to the second attenuated voltage;
• receiving by a controller representations of the first detector output and the second detector output;
• and
• calculating an impedance adjustment using the representations of the first detector output and the second detector output.

An integrated circuit comprising:

• a plurality of LC delay circuit blocks connected in series, the LC delay circuit blocks forming an artificial transmission line adapted to carry an RF signal, the RF signal being intended for transmission by an antenna;
• a plurality of nodes located such that a different node is located on either side of each LC delay circuit block, each node being a location for sensing a voltage on the artificial transmission line;
• a plurality of variable attenuators connected such that a different variable attenuator is connected to a different node of the plurality of nodes, each attenuator is configured to attenuate a sensed voltage at the node and to provide an attenuated voltage output;
• at least one detector configured to receive at least one attenuated voltage output and detect an attenuated voltage level, the at least one detector is further configured to provide a detected voltage output;
• and
• a multiplexer switch connected to receive the detected voltage outputs from the at least one detector and configured to provide a multiplexed detected voltage output.