Radio-frequency apparatus with multi-band balun with improved performance and associated methods
An apparatus includes an RF apparatus, and a multi-band matching balun coupled to the RF apparatus. The multi-band matching balun includes at least one three-element frequency-dependent resonator (TEFDR) and at most three reactive elements.
1. An apparatus, comprising:
a radio-frequency (RF) apparatus; and
a multi-band matching balun using passive components, the multi-band matching balun coupled to the RF apparatus, the multi-band matching balun including at least one three-element frequency-dependent resonator (TEFDR) and at most three reactive elements,
wherein the at least one TEFDR provides functionality of an inductor having a frequency-dependent inductance or a capacitor having a capacitance having a frequency-dependent capacitance.
2. The apparatus according to claim 1 , wherein the RF apparatus comprises receive circuitry or transmit circuitry.
3. The apparatus according to claim 1 , wherein the RF apparatus comprises both receive circuitry and transmit circuitry.
4. The apparatus according to claim 1 , wherein the at least one three-element frequency-dependent resonator comprises: (a) two inductors coupled to one capacitor; or (b) one inductor coupled to two capacitors.
5. The apparatus according to claim 1 , wherein the at most three reactive elements comprise at least one capacitor or at least one inductor.
6. The apparatus according to claim 1 , wherein the at least one three-element frequency-dependent resonator realizes an inductor having an inductance that varies as a function of frequency.
7. The apparatus according to claim 1 , wherein the at least one three-element frequency-dependent resonator realizes a capacitor having a capacitance that varies as a function of frequency.
8. The apparatus according to claim 1 , wherein the three-element frequency-dependent resonator provides impedance matching between the RF apparatus and either a filter or an antenna.
9. The apparatus according to claim 1 , wherein the three-element frequency-dependent resonator provides balun functionality between the RF apparatus and either a filter or an antenna.
10. An apparatus, comprising:
a radio-frequency (RF) apparatus; and
a multi-band matching balun coupled to the RF apparatus, the multi-band matching balun comprising at least one three-element frequency-dependent resonator (TEFDR) and at most three lumped reactive elements (LREs),
wherein neither the at least one three-element frequency-dependent resonator nor the at most three lumped reactive elements comprises variable or tunable capacitors or inductors, and
wherein the at least one TEFDR provides functionality of an inductor having a frequency-dependent inductance or a capacitor having a capacitance having a frequency-dependent capacitance.
11. The apparatus according to claim 10 , wherein three-element frequency-dependent resonator realizes an inductor having an inductance that varies as a function of frequency.
12. The apparatus according to claim 10 , wherein the three-element frequency-dependent resonator realizes a capacitor having a capacitance that varies as a function of frequency.
13. The apparatus according to claim 10 , wherein the three-element frequency-dependent resonator comprises either: (a) two capacitor and an inductor, or (b) two inductors and a capacitor.
14. The apparatus according to claim 10 , wherein the multi-band matching balun further comprises a capacitor coupled to the at least one three-element frequency-dependent resonator to realize a second-harmonic trap.
15. A method of operating an apparatus that includes a radio-frequency (RF) apparatus, the method comprising using a multi-band matching balun using passive components, the multi-band matching balun coupled to the RF apparatus to provide impedance matching and balun functionality, wherein the multi-band matching balun includes at least one three-element frequency-dependent resonator (TEFDR) and at most three reactive elements, wherein the at least one TEFDR provides functionality of an inductor having a frequency-dependent inductance or a capacitor having a capacitance having a frequency-dependent capacitance.
16. The method according to claim 15 , wherein the three-element frequency-dependent resonator realizes an inductor having an inductance that varies as a function of frequency.
17. The method according to claim 16 , wherein the three-element frequency-dependent resonator realizes a capacitor having a capacitance that varies as a function of frequency.
18. The method according to claim 15 , wherein the three-element frequency-dependent resonator provides impedance matching between the RF apparatus and either a filter or an antenna.
19. The method according to claim 15 , wherein the three-element frequency-dependent resonator provides balun functionality between the RF apparatus and either a filter or an antenna.
20. The method according to claim 15 , wherein the at least one three-element frequency-dependent resonator comprises: (a) two inductors coupled to one capacitor; or (b) one inductor coupled to two capacitors.