Transmitter architecture for uplink inter-band carrier aggregation
View Patent ↗A transmitter architecture and methodologies supporting uplink inter-band carrier aggregation (CA). In various embodiments, first and second baseband signals are provided to a plurality of passive mixers that selectively combine the baseband signals with differing local oscillation signals to produce outbound RF signals of at least first and second RF frequencies. Depending on the relevant CA mode of operation, the outbound RF signals are amplified and selectively coupled to at least one transmitting antenna for respective transmission over a plurality of frequency bands.
1. A wireless communication device comprising:
digital processing circuitry configured to:
divide digital data into a first digital information signal and a second digital information signal; and
generate a carrier aggregation control signal based upon a carrier aggregation mode of operation;
first baseband circuitry configured to convert the first digital information signal into a first baseband signal;
second baseband circuitry configured to convert the second digital information signal into a second baseband signal;
local oscillation (LO) circuitry configured to produce a first LO signal and a differing second LO signal based upon the carrier aggregation control signal;
first RF signal path circuitry configured to service a first frequency band, comprising:
a first passive mixer configured to mix the first baseband signal and the first LO signal to produce a first RF signal at a first RF frequency;
a second passive mixer configured to mix the second baseband signal and the second LO signal to produce a second RF signal at a second RF frequency that differs from the first RF frequency, the output of the first passive mixer coupled to the output of the second passive mixer to produce a first outbound RF signal;
first enablement circuitry configured to selectively provide the first LO signal to the first passive mixer or the second LO signal to the second passive mixer; and
a first amplifier configured to amplify the first outbound RF signal; and
second RF signal path circuitry configured to service a second frequency band, comprising:
a third passive mixer configured to mix the first baseband signal and the first LO signal to produce a third RF signal at a third RF frequency;
a fourth passive mixer configured to mix the second baseband signal and the second LO signal to produce a fourth RF signal at a fourth RF frequency that differs from the third RF frequency, the output of the third passive mixer coupled to the output of the fourth passive mixer to produce a second outbound RF signal;
second enablement circuitry configured to selectively provide the first LO signal to the third passive mixer or the second LO signal to the fourth passive mixer; and
a second amplifier configured to amplify the second outbound RF signal.
2. The wireless communication device of claim 1 , further comprising third RF signal path circuitry configured to service a third frequency band, comprising:
a fifth passive mixer configured to mix the second baseband signal and the second LO signal to produce a fifth RF signal at a fifth RF frequency;
third enablement circuitry configured to selectively provide the second LO signal to the fifth passive mixer; and
a third amplifier configured to amplify the fifth RF signal.
3. The wireless communication device of claim 2 , further comprising signal coupling circuitry configured to selectively couple the first outbound RF signal, the second outbound RF signal and the fifth RF signal to at least one transmitting antenna.
4. The wireless communication device of claim 3 , wherein each of the first passive mixer, the second passive mixer, the third passive mixer, the fourth passive mixer, and the fifth passive mixer is selectively enabled based upon the carrier aggregation mode of operation.
5. The wireless communication device of claim 3 , wherein:
in a first carrier aggregation mode of operation supporting inter-band carrier aggregation, the first RF signal is transmitted in the first frequency band and the fourth RF signal is transmitted in the second frequency band;
in a second carrier aggregation mode of operation supporting inter-band carrier aggregation, the second RF signal is transmitted in the first frequency band and the third RF signal is transmitted in the second frequency band;
in a third carrier aggregation mode of operation supporting inter-band carrier aggregation, the first RF signal is transmitted in the first frequency band and the fifth RF signal is transmitted in the third frequency band; and
in a fourth carrier aggregation mode of operation supporting inter-band carrier aggregation, the third RF signal is transmitted in the second frequency band and the fifth RF signal is transmitted in the third frequency band.
6. The wireless communication device of claim 1 , wherein:
in a first carrier aggregation mode of operation supporting inter-band carrier aggregation, the first RF signal is transmitted in the first frequency band and the fourth RF signal is transmitted in the second frequency band; and
in a second carrier aggregation mode of operation supporting inter-band carrier aggregation, the second RF signal is transmitted in the first frequency band and the third RF signal is transmitted in the second frequency band.
7. The wireless communication device of claim 1 , wherein each of the first passive mixer, the second passive mixer, the third passive mixer, and the fourth passive mixer are selectively enabled based upon the carrier aggregation mode of operation.
8. The wireless communication device of claim 1 , wherein the LO circuitry includes:
a first multiplexer configured to multiplex between the first LO signal used in a Frequency Division Duplex (FDD) mode of operation and a first received LO signal used in a Time Division Duplex (TDD) mode of operation; and
a second multiplexer configured to multiplex between the second LO signal used in a FDD mode of operation and a second received LO signal used in a TDD mode of operation.
9. A method for operating a wireless communication device comprising:
generating a carrier aggregation control signal based upon a carrier aggregation mode of operation;
dividing digital data into a first digital information signal and a second digital information signal;
converting the first digital information signal into a first baseband signal;
converting the second digital information signal into a second baseband signal;
generating a first local oscillation (LO) signal;
generating a differing second LO signal based upon the carrier aggregation control signal;
by first RF signal path circuitry configured to service a first frequency band:
selectively enabling either a first passive mixer or a second passive mixer to produce a first outbound RF signal, wherein:
the first passive mixer, when enabled, mixes the first baseband signal and the first LO signal to produce a first RF signal at a first RF frequency;
the second passive mixer, when enabled, mixes the second baseband signal and the second LO signal to produce a second RF signal at a second RF frequency that differs from the first RF frequency, wherein the first RF signal or the second RF signal is the first outbound RF signal; and
amplifying the first outbound RF signal; and
by second RF signal path circuitry configured to service a second frequency band:
selectively enabling either a third passive mixer or a fourth passive mixer to produce a second outbound RF signal, wherein:
the third passive mixer, when enabled, mixes the first baseband signal and the first LO signal to produce a third RF signal at a third RF frequency;
the fourth passive mixer, when enabled, mixes the second baseband signal and the second LO signal to produce a fourth RF signal at a fourth RF frequency that differs from the third RF frequency, wherein the third RF signal or the fourth RF signal is the second outbound RF signal; and
amplifying the second outbound RF signal.
10. The method of claim 9 , further comprising, in third RF signal path circuitry configured to service a third frequency band:
selectively enabling a fifth passive mixer to mix the second baseband signal and the second LO signal to produce a fifth RF signal at a fifth RF frequency; and
amplifying the fifth RF signal.
11. The method of claim 10 , further comprising selectively coupling the first outbound RF signal, the second outbound RF signal and the fifth RF signal to at least one transmitting antenna.
12. The method of claim 10 , wherein the first passive mixer, the second passive mixer, the third passive mixer, the fourth passive mixer, and the fifth passive mixer are selectively enabled based upon the carrier aggregation mode of operation.
13. The method of claim 10 , wherein:
in a first carrier aggregation mode of operation supporting inter-band carrier aggregation, the first RF signal is transmitted in the first frequency band and the fourth RF signal is transmitted in the second frequency band;
in a second carrier aggregation mode of operation supporting inter-band carrier aggregation, the second RF signal is transmitted in the first frequency band and the third RF signal is transmitted in the second frequency band;
in a third carrier aggregation mode of operation supporting inter-band carrier aggregation, the first RF signal is transmitted in the first frequency band and the fifth RF signal is transmitted in the third frequency band; and
in a fourth carrier aggregation mode of operation supporting inter-band carrier aggregation, the third RF signal is transmitted in the second frequency band and the fifth RF signal is transmitted in the third frequency band.
14. The method of claim 9 , wherein:
in a first carrier aggregation mode of operation supporting inter-band carrier aggregation, the first RF signal is transmitted in the first frequency band and the fourth RF signal is transmitted in the second frequency band; and
in a second carrier aggregation mode of operation supporting inter-band carrier aggregation, the second RF signal is transmitted in the first frequency band and the third RF signal is transmitted in the second frequency band.
15. The method of claim 9 , further comprising selectively disabling each of the first passive mixer, the second passive mixer, the third passive mixer, and the fourth passive mixer based upon the carrier aggregation mode of operation.
16. The method of claim 9 , further comprising:
multiplexing between the first LO signal used in a Frequency Division Duplex (FDD) mode of operation and a first received LO signal used in a Time Division Duplex (TDD) mode of operation; and
multiplexing between the second LO signal used in a FDD mode of operation and a second received LO signal used in a TDD mode of operation.
17. A radio frequency integrated circuit (RF IC) comprising:
digital processing circuitry configured to:
divide digital data into a first digital information signal and a second digital information signal; and
generate a carrier aggregation control signal based upon a carrier aggregation mode of operation;
first baseband circuitry configured to convert the first digital information signal into a first baseband signal;
second baseband circuitry configured to convert the second digital information signal into a second baseband signal;
local oscillation (LO) circuitry configured to produce a first LO signal and a differing second LO signal based upon the carrier aggregation control signal;
first RF signal path circuitry configured to service a first frequency band, comprising:
a first passive mixer configured to mix the first baseband signal and the first LO signal to produce a first RF signal at a first RF frequency;
a second passive mixer configured to mix the second baseband signal and the second LO signal to produce a second RF signal at a second RF frequency that differs from the first RF frequency, the output of the first passive mixer coupled to the output of the second passive mixer to produce a first outbound RF signal;
first enablement circuitry configured to selectively provide the first LO signal to the first passive mixer or the second LO signal to the second passive mixer; and
a first amplifier configured to amplify the first outbound RF signal; and
second RF signal path circuitry configured to service a second frequency band, comprising:
a third passive mixer configured to mix the first baseband signal and the first LO signal to produce a third RF signal at a third RF frequency;
a fourth passive mixer configured to mix the second baseband signal and the second LO signal to produce a fourth RF signal at a fourth RF frequency that differs from the third RF frequency, the output of the third passive mixer coupled to the output of the fourth passive mixer to produce a second outbound RF signal; and
second enablement circuitry configured to selectively provide the first LO signal to the third passive mixer or the second LO signal to the fourth passive mixer; and
a second amplifier configured to amplify the second outbound RF signal.
18. The RF IC of claim 17 , further comprising signal coupling circuitry configured to selectively couple the first outbound RF signal and the second outbound RF signal to at least one transmitting antenna.
19. The RF IC of claim 17 , wherein each of the first passive mixer, the second passive mixer, the third passive mixer, and the fourth passive mixer are selectively enabled based upon the carrier aggregation mode of operation.
20. The RF IC of claim 17 , wherein the LO circuitry further comprises:
a first multiplexer configured to multiplex between the first LO signal used in a Frequency Division Duplex (FDD) mode of operation and a first received LO signal used in a Time Division Duplex (TDD) mode of operation; and
a second multiplexer configured to multiplex between the second LO signal used in a FDD mode of operation and a second received LO signal used in a TDD mode of operation.