We study the Braverman–Kazhdan proposal for the local spherical situation. In the
-adic
case, we give a definition of the spherical component of conjectural space
and the
-Fourier
transform kernel
,
and verify several conjectures of Braverman and Kazhdan (GAFA
2000 special volume, part I, 237–278) in this situation. In the
archimedean case, we study the asymptotic of the basic function
and the
-Fourier
transform kernel
.