Radio-frequency circuitry with shapable differential coupled lines for low-loss impedance matching

1 . Circuitry comprising:

a first amplifier; and

differential coupled lines having

a first pair of coupled lines connected to a first output terminal of the first amplifier, wherein the first pair of coupled lines includes a first conductive path having a first end coupled to the first output terminal and a second end coupled to a bias voltage line and a second conductive path routed along the first conductive path and having a first end directly connected to a ground line, and

a second pair of coupled lines connected to a second output terminal of the first amplifier, wherein the second pair of coupled lines includes a third conductive path having a first end coupled to the second output terminal and a second end coupled to the bias voltage line and a fourth conductive path, separate from the second conductive path, routed along the third conductive path and having a first end directly connected to the ground line.

2 . The circuitry of claim 1 , wherein the first end of the first conductive path is directly connected to the first output terminal of the first amplifier and wherein the first end of the third conductive path is directly connected to the second output terminal of the first amplifier.

3 . The circuitry of claim 1 , further comprising a transformer directly connected to an input of the first amplifier.

4 . The circuitry of claim 1 , further comprising a differential line directly connected to an input of the first amplifier.

5 . The circuitry of claim 1 , wherein the second and fourth conductive paths have second ends coupled to one or more antennas.

6 . The circuitry of claim 1 , further comprising a second amplifier configured to receive a signal via the differential coupled lines.

7 . The circuitry of claim 6 , wherein the second amplifier includes:

a first input terminal coupled to a second end of the second conductive path; and

a second input terminal coupled to a second end of the fourth conductive path.

8 . The circuitry of claim 7 , further comprising:

a first differential transmission line coupled between the first amplifier and the differential coupled lines; and

a second differential transmission line coupled between the differential coupled lines and the second amplifier.

9 . The circuitry of claim 7 , further comprising:

a differential transmission line coupled between the first amplifier and the differential coupled lines or between the differential coupled lines and the second amplifier.

10 . The circuitry of claim 7 , wherein the differential coupled lines are configured to provide impedance matching between the first and second amplifiers.

11 . The circuitry of claim 1 , wherein the differential coupled lines are configured to provide impedance matching at the first and second output terminals of the first amplifier.

12 . The circuitry of claim 1 , wherein the first pair of coupled lines comprise edge-coupled strip lines, edge-coupled coplanar waveguides, or a broadside-coupled strip lines.

13 . The circuitry of claim 1 , further comprising:

additional differential coupled lines having a third pair of coupled lines connected to a third output terminal of the first amplifier and a fourth pair of coupled lines connected to a fourth output terminal of the first amplifier.

14 . The circuitry of claim 13 , further comprising:

first differential lines coupled between the first output terminal and the first pair of coupled lines;

second differential lines coupled between the second output terminal and the second pair of coupled lines;

third differential lines coupled between the third output terminal and the third pair of coupled lines; and

fourth differential lines coupled between the fourth output terminal and the fourth pair of coupled lines.

15 . The circuitry of claim 14 , further comprising:

a second amplifier having an input coupled to the differential coupled lines; and

a third amplifier having an input coupled to the additional differential coupled lines.

16 . The circuitry of claim 15 , further comprising:

a fourth amplifier having an input coupled to the differential coupled lines; and

a fifth amplifier having an input coupled to the additional differential coupled lines.

17 . The circuitry of claim 16 , further comprising:

fifth differential lines having a first end coupled to the differential coupled lines and a second end coupled to the second and fourth amplifiers; and

sixth differential lines having a first end coupled to the additional differential coupled lines and a second end coupled to the third and fifth amplifiers.

18 . The circuitry of claim 17 , wherein:

the second amplifier has outputs coupled to a first pair of antennas;

the third amplifier has outputs coupled to a second pair of antennas;

the fourth amplifier has outputs coupled to a third pair of antennas; and

the fifth amplifier has outputs coupled to a fourth pair of antennas.

19 . A method of operating circuitry, comprising:

with a first amplifier, outputting radio-frequency signals at first and second output terminals of the first amplifier;

with a first conductive path having a first end coupled to the first output terminal and a second end coupled to a bias voltage line, conveying a first portion of the radio-frequency signals;

with a second conductive path routed along the first conductive path and having a first end directly connected to a ground line, conveying the first portion of the radio-frequency signals;

with a third conductive path having a first end coupled to the second output terminal and a second end coupled to the bias voltage line, conveying a second portion of the radio-frequency signals; and

with a fourth conductive path separate from the second conductive path, routed along the third conductive path, and having a first end directly connected to the ground line, conveying the second portion of the radio-frequency signals.

20 . The method of claim 19 , further comprising:

with the first and second conductive paths, providing impedance matching at the first output terminal; and

with the third and fourth conductive paths, providing impedance matching at the second output terminal.

21 . The method of claim 19 , further comprising:

with a second amplifier, receiving the radio-frequency signals via the first, second, third, and fourth conductive paths, wherein the second amplifier has a first input coupled to a second end of the second conductive path and a second input coupled to a second end of the fourth conductive path.

22 . The method of claim 19 , further comprising:

with a third amplifier, receiving the radio-frequency signals via the first, second, third, and fourth conductive paths.

23 . The method of claim 22 , further comprising:

with the second amplifier, outputting radio-frequency signals to a first set of antennas; and

with the third amplifier, outputting radio-frequency signals to a second set of antennas.

24 . The method of claim 19 , further comprising:

with the first amplifier, outputting radio-frequency signals at third and fourth output terminals of the first amplifier;

with a fifth conductive path having a first end coupled to the third output terminal and a second end coupled to the bias voltage line, conveying a third portion of the radio-frequency signals;

with a sixth conductive path routed along the fifth conductive path and having a first end directly connected to the ground line, conveying the third portion of the radio-frequency signals;

with a seventh conductive path having a first end coupled to the fourth output terminal and a second end coupled to the bias voltage line, conveying a fourth portion of the radio-frequency signals; and

with an eighth conductive path routed along the seventh conductive path and having a first end directly connected to the ground line, conveying the fourth portion of the radio-frequency signals.

25 . The method of claim 24 , further comprising:

with a second amplifier, receiving the first and second portions of the radio-frequency signals via the first, second, third, and fourth conductive paths, wherein the second amplifier has a first input coupled to a second end of the second conductive path and a second input coupled to a second end of the fourth conductive path; and

with a third amplifier, receiving the third and fourth portions of the radio-frequency signals via the fifth, sixth, seventh, and eighth conductive paths, wherein the third amplifier has a first input coupled to a second end of the sixth conductive path and a second input coupled to a second end of the eighth conductive path.