Strategies for improved linearization in BAW multiplexer modules

Carrier aggregation (CA) and the resulting increasing number of filter chips per multiplexer modules has significantly changed linearity requirements. Accurate prediction of non-linear performance in BAW is crucial to be able to optimize a design of a filter for the required linearity specifications. Aspects for model simplification in simulation are discussed and examples given to show the sensitivity of non-linear prediction accuracy on the model. The scope of the paper is to present general approaches to improve the linearity in a single BAW filter, considering as well additional constraints and challenges applying for multiplexer modules. Factors for response variation as well as the effects of acoustic modes on the non-linearity are presented.