RADIO FREQUENCY MULTIPLEXER

摘要

A method and apparatus for routing transmit and receive signals in a radio RF front end. According to one aspect, the disclosure provides a multiplexer method and apparatus for routing transmit signals to an antenna and routing amplified receive signals to a receiver. The multiplexer includes a first hybrid coupler having a first frequency response and at least one other hybrid coupler having a second frequency response. The at least one other hybrid coupler is coupled to the first hybrid coupler by a first and second splitters each cascaded with a set of amplifying circuits for balanced amplification. In some embodiments, the second frequency response complements the first frequency response to increase cancellation of two signals arriving at an output port of the at least one other hybrid coupler from two different paths through the first and the at least one other hybrid couplers.