Electrical Multiband Component

1 . An electrical multiband component comprising:

at least three signal paths each signal path for the transmitting signals in a corresponding frequency band;

a frequency-separating filter having an input side and an output side, the input side being electrically connected to an antenna path and the output side being electrically connected to the signal paths; and

wherein a bandpass filter comprising a double mode surface acoustic wave (SAW) filter in at least one of the signal paths.

2 . The electrical multiband component of claim 1 , wherein the at least three signal paths comprise:

a first signal path for use in transmitting signals in a first frequency band;

a second signal path for use in transmitting signals in a second frequency band; and

a third signal path for use in transmitting signals in a third frequency band;

wherein the bandpass filter is in the third signal path.

3 . The electrical multiband component of claim 2 , wherein the frequency-separating filter comprises a first diplexer and a second diplexer;

wherein the second diplexer is configured to interface the second and third signal paths to a common path; and

wherein the first diplexer is configured to interface the common path and first signal path to the antenna path.

4 . The electrical multiband component of claim 3 , wherein first diplexer comprises a first low-pass filter and a first high-pass filter; and

wherein first high-pass filter interfaces to the common path and the first low-pass filter interfaces to the first signal path.

5 . The electrical multiband component of claim 4 , wherein the second diplexer comprises a second low-pass filter and a second high-pass filter; and

wherein the second low-pass filter interfaces to the third signal path and second high-pass filter to the second signal path.

6 . The electrical multiband component of claim 2 , wherein the bandpass filter has a stopband in the second frequency band.

7 . The electrical multiband component of claim 2 , wherein the bandpass filter has a stopband in the first frequency band.

8 . The electrical multiband component of claim 2 , wherein, for a center frequency f 1 of the first frequency band, a center frequency f 2 of the second frequency band, and a center frequency f 3 of the third frequency band: f 1 <f 3 <f 2 .

9 . The electrical multiband component of claim 8 , wherein: f 3 ≧2f 1 .

10 . The electrical multiband component of claim 8 , wherein: f 3 <f 2 <1.5f 3 .

11 . The electrical multiband component of claim 2 , wherein the first and second signal paths are transceiver paths; and

wherein the third signal path is a receive path.

12 . The electrical multiband component of claim 2 , wherein the first and second signal paths are each configured for transmission of mobile radio band signals; and

wherein the third signal path is configured for transmission of global positioning system (GPS) signals.

13 . The electrical multiband component of claim 2 , wherein the double mode SAW filter comprises an acoustic track comprising at least five transducers.

14 . The electrical multiband component of claim 13 , wherein the double mode SAW filter comprises:

input transducers in parallel; and

output transducers in parallel;

wherein an input transducer is between two of the output transducer; or

wherein an output transducer is between two of the input transducers.

15 . The electrical multiband component of claim 2 , wherein the bandpass filter comprises at least one first resonator upstream of the double mode SAW filter relative to the antenna Path.

16 . The electrical multiband component of claim 15 , wherein the bandpass filter comprises at least one second resonator downstream of the double mode SAW filter relative to the antenna path.

17 . The electrical multiband component of claim 16 , wherein at least one first resonator or second resonator comprises a series resonator.

18 . The electrical multiband component of claim 16 , wherein at least one first resonator or second resonator comprises a parallel resonator.

19 . The electrical multiband component of claim 16 , wherein at least one first resonator or second resonator comprises part of at least one ladder-type element.

20 . The electrical multiband component of claim 1 , wherein the bandpass filter has a symmetrical output.

21 . The electrical multiband component of claim 5 , wherein the second high-pass filter has a transfer function that has a pole at a frequency located essentially in the first frequency band or the third frequency band.

22 . The electrical multiband component of claim 5 , wherein the first signal path comprises a third low-pass filter.

23 . The electrical multiband component of claim 22 , wherein the third low-pass filter has a transfer function that has a pole at a frequency located essentially in the second frequency band or the third frequency band.

24 . The electrical multiband component of claim 5 , further comprising:

a first matching network downstream of the second low-pass filter relative to the antenna path.

25 . The electrical multiband component of claim 24 , further comprising:

a second matching network downstream of the bandpass filter relative to the antenna input.

26 . The electrical multiband component of claim 2 , wherein the second and third signal paths are receive paths and the first signal path is a transmit/receive path; or

wherein the first and third signal paths are receive paths and the second signal path is a transmit/receive path.

27 . The electrical multiband component of claim 1 ,

wherein the frequency-separating filter comprises the bandpass filter and a diplexer; and

wherein the diplexer interfaces first and second signal paths to a common path that is connected to a third signal path and to an antenna path.

28 . The electrical multiband component of claim 1 , which is surface-mountable.

29 . The electrical multiband component of claim 28 , further comprising:

a carrier substrate;

wherein the bandpass filter comprises a chip that is mounted on the carrier substrate.

30 . The electrical multiband component of claim 29 , wherein the carrier substrate comprises metallization planes and ceramic layers among the metallization planes.

31 . The electrical multiband component of claim 29 , wherein the frequency-separating filter is integrated, at least in part, into the carrier substrate.

32 . The electrical multiband component 27 , wherein in at least one of the first and second signal paths comprises a duplexer.

33 . The electrical multiband component of claim 32 , wherein the duplexer is integrated, at least in part, on a carrier substrate on which the bandpass filter is mounted.

34 . The electrical multiband component of claim 33 , further comprising:

at least one amplifier mounted on the carrier substrate, the at least one amplifier being in at least one of the first and second signal paths.

35 . The electrical multiband component of claim 34 , further comprising:

an additional signal path that is electromagnetically coupled, via a directional coupler, to a transmission branch of the first signal path or the second signal path; and

wherein the directional coupler is integrated in the carrier substrate or is on the carrier substrate.

36 . The electrical multiband component of claim 35 , wherein the additional signal path is electromagnetically coupled to the transmission branch of the first signal path and to the transmission branch of the second signal path.