Alternative diplexer-based acoustic unwanted spurs and losses reduction technique

A method of filtering a radio frequency (RF) signal, comprising:

• receiving the RF signal at an input terminal;
• splitting the RF signal so that a first split RF signal is transmitted through a first filter path and a second split RF signal is transmitted through a second filter path;
• filtering the first split RF signal with an acoustic filter, wherein the acoustic filter defines a notch and a first filter response, wherein the first filter response is a first type of filter response;
• filtering the second split RF signal with second filter in the second filter path, the second filter being at least one of a lumped element filter and a printed element filter, wherein second filter defines a second type of filter response;
• recombining the first split RF signal and the second split RF signal into a recombined RF signal;
• wherein the first type of filter response is one of either a low pass response or a high pass response;
• and
• wherein the second type of filter response is of another one of the low pass type filter response or the high pass type filter response.

A user element comprising a radio frequency (RF) circuit, the RF circuit comprising:

• an input terminal;
• an output terminal;
• a first filter path connected between the input terminal and the output terminal, wherein the first filter path includes an acoustic filter that defines a notch and a first filter response, wherein the first filter response is a first type of filter response;
• a second filter path connected between the input terminal and the output terminal, wherein the second filter path includes a second filter that is at least one of a lumped element filter and a printed element filter, wherein second filter defines a second type of filter response;
• wherein the first type of filter response is one of either a low pass response or a high pass response;
• and
• wherein the second type of filter response is of another one of the low pass response or the high pass response.