The desiccant coated heat exchanger (DCHE) is a novel type of solid desiccant equipment that can simultaneously handle both latent and sensible loads. The systems based on DCHE are considered as a promising alternative to dehumidification in conventional air conditioning because of their precise ability to control humidity. In addition, these systems are energy efficient as they utilise low-grade energy resources for desiccant regeneration. The present study proposes an advanced wavy fin DCHE, which can provide better dehumidification than conventional plain fin configuration. The heat and mass transfer characteristics of the proposed DCHE are numerically evaluated by developing a novel one-dimensional mathematical model. The model is validated with the experimental and numerical results in the literature. The transient variation of outlet temperature and humidity ratio of air from the plain and wavy fin DCHEs were compared. The investigation reveals that the dehumidification capacity of the proposed wavy fin DCHE is 61% higher than that of the plain fin DCHE. Further, an effective dehumidification and regeneration time is proposed for maximising the performance of DCHE. A detailed parametric study and sensitivity analysis are conducted to investigate the effect of geometric and operating parameters on the performance of DCHE. The study also presents a guide for selecting suitable geometry while designing the DCHE system with a wavy fin configuration.