Modified dual band direct conversion architecture that allows extensive digital calibration

A communication device may include one or more circuits in an integrated transmitter and receiver that includes a transmit path and a receive path. The transmit path may include an I processing baseband transmit path and a Q processing baseband transmit path. The receive path may include an I processing baseband receive path and a Q processing baseband receive path. The one or more circuits may enable sharing a first common filter by the I processing baseband transmit path and the I processing baseband receive path. The one or more circuits may also enable sharing a second common filter by the Q processing baseband transmit path and the Q processing baseband receive path. The first common filter and the second common filter are independently programmable to adjust a phase and/or a gain of the said first common filter, and/or a phase and/or a gain of the second common filter.