paths for these reflected signals are illustrated by the dotted directional lines 443 in fig4 b during the receive mode when the txen 411 is set at a mode such as mode u201c 0 u201d the following are the settings for the switches switch 423 port 1 is connected to port 3 such that the receive signal port is connected to the antenna switch 417 port 1 is connected to port 2 this forms a receive path for received signals the resistance rl 4 418 is not connected and not enabled switch 419 port 1 is connected to port 2 such that the switch is in the on position and power is supplied to the lna 415 from the power supply 420 switch 403 port 1 is connected to port 3 the transmit path for transmitting signals is disconnected and the resistance rl 3 404 that can be for example a 500 ohm load is enabled and connected to terminal c of circulator 402 rl 3 may be a matching impedance for terminal c of circulator 402 switch 409 port 1 is connected from port 2 this switch is in the on position and the resistance rl 1 408 is enabled to prevent receiver pass circuit mismatching rl 1 together with the output impedance of the pa 405 may form a matching impedance for terminal c of the circulator 10 switch 414 port 1 is not connected to port 2 this switch is in the off.