On calibrated representations and the Plancherel Theorem for affine Hecke algebras

This paper has two main purposes. Firstly we generalise Ram's explicit construction of calibrated representations of the affine Hecke algebra to the multi-parameter case (including the non-reduced $BC_n$ case). We then derive the Plancherel formulae for all rank~1 and rank~2 affine Hecke algebras including a construction of all representations involved (following work of Opdam).