I am trying to implement BGM model for Libor rates.

I am following the road map given in the project 11 in theory and concepts.

For my work I need to calibrate the model to caplet prices as well as to swaptions.

One of my very basic doubt is:

once i calibrate to caplets, all the volatility parameters (a,b,c,d,K's) and the correlation parameter \beta is known.

Then how can i calibrate to swaption prices? as theres know more parameters left for matching.

Thank you very much in advance