IQ Impairments and Correction in Wideband Transmitters
(Room 204)
18 Oct 18
2:00 PM
-
2:30 PM
With the advent of 5G networks, high throughput GEO satellites and LEO satellites, the demand for Tx and Rx bandwidth has increased considerably. With the increased bandwidth comes new analog/RF challenges, and effects that were once secondary become a primary consideration in designs. The new challenges are particularly noticeable in IQ phase and amplitude imbalance in direct conversion topology that becomes baseband frequency dependent which is commonly treated as constant over baseband information. The paper will derive implications of baseband frequency dependent on image suppression as well separation of baseband imbalances vs LO dependent imbalances. A discussion on environmental impacts on LO and baseband based imbalances along with implications on corrective measures such as passive or adaptive correction. Finally, the paper will culminate in a discussion of imbalance detection circuitry and algorithm along with implications on digital compensation.