Method and apparatus for reduced noise and carrier feedthrough in multimode transmitter

A multimode apparatus configurable to support a plurality of communication standards, the apparatus comprising:

• a first transceiver selectively configurable to support a first communication mode of the plurality of communication modes, the first transceiver including a first transmitter and a first receiver;
• a second transceiver selectively configurable to support a second communication mode of the plurality of communication modes, the second transceiver including a second transmitter and a second receiver, and wherein the second receiver is configured to be a portion of a carrier feedthrough cancellation loop of the first transmitter when the multimode apparatus is configured to support the first communication mode;
• an RF switch configured to couple an output of the first transmitter to an input of the second receiver when the multimode apparatus is configured to support the first communication mode;
• and
• a carrier compensation module having an input coupled to an output of the second receiver when the multimode apparatus is configured to support the first communication mode, an output coupled to a baseband portion of the first transmitter, and configured to generate a carrier feedthrough cancellation signal based at least in part on a signal output by the second receiver,
• wherein the carrier compensation module is configured to generate a DC offset value based on a DC value of the signal output by the second receiver, and sum the DC offset value with a baseband signal of the first transmitter.