Wideband transmitter front-end
One embodiment of the present invention provides a transmitter for wireless communication. The transmitter includes a wideband tunable modulator, a number of power amplifiers with a particular power amplifier associated with a particular frequency range, and a wideband power amplifier (PA) driver. The PA driver is configured to receive an output signal from the wideband tunable modulator, amplify the output signal, and send the amplified output signal to at least one of the power amplifiers.
1. A transmitter for wireless communication, comprising:
a wideband tunable modulator, wherein the wideband tunable modulator includes an amplifier, and wherein a bandwidth of the amplifier is compensated for by using an inductive peaking technique;
a number of power amplifiers, wherein a particular power amplifier is associated with a particular frequency range; and
a wideband power amplifier (PA) driver configured to:
receive an output signal from the wideband tunable modulator;
amplify the output signal; and
send the amplified output signal to at least one of the power amplifiers.
2. The transmitter of claim 1 , further comprising a single-pole multiple-throw switch situated between the wideband PA driver and the power amplifiers, wherein the switch is configured to switch the amplified output signal to one of the power amplifiers based on a carrier frequency of the output signal.
3. The transmitter of claim 1 , wherein the wideband tunable modulator and the power amplifiers are located on a same integrated circuit (IC) chip.
4. The transmitter of claim 1 , wherein the wideband tunable modulator is a quadrature modulator.
5. The transmitter of claim 1 , wherein the wideband tunable modulator has a tuning range between 300 MHz and 3.6 GHz.
6. The transmitter of claim 1 , wherein the wideband PA driver includes a cascode amplifier.
7. The transmitter of claim 6 , wherein the cascode amplifier has two poles.
8. The transmitter of claim 7 , wherein the cascode amplifier includes an inductor that is serially coupled to a parasitic capacitor.
9. The transmitter of claim 8 , wherein the inductor has an inductance between 0.5 nH and 10 nH.
10. The transmitter of claim 1 , wherein the wideband PA driver has a 10 dB bandwidth that is up to 3.6 GHz.
11. A method for generating a transmitter output for wireless communication, comprising:
receiving a baseband signal;
modulating the baseband signal onto an RF carrier, wherein the RF carrier has a frequency that ranges from 300 MHz to 3.6 GHz, wherein modulating the baseband signal is performed by an on-chip tunable modulator, wherein the on-chip tunable modulator includes an amplifier, and wherein a bandwidth of the amplifier is compensated for by using an inductive peaking technique;
pre-amplifying the modulated signal using a single on-chip amplifier driver regardless of the RF carrier frequency; and
sending the pre-amplified modulated signal to a power amplifier selected from a group of power amplifiers based on the RF carrier frequency.
12. The method of claim 11 , wherein the amplifier is a cascode amplifier.
13. The method of claim 11 , wherein modulating the baseband signal involves quadrature modulating.
14. The method of claim 11 , wherein pre-amplifying the modulated signal is performed by a cascode amplifier.
15. The method of claim 14 , wherein the cascode amplifier has two poles.
16. The method of claim 15 , wherein the cascode amplifier includes an inductor that is serially coupled to a parasitic capacitor.
17. The method of claim 16 , wherein the inductor has an inductance between 0.5 nH and 10 nH.