A channel estimation method estimates a data channel of a data resource element of a physical resource block in a time-frequency domain. The method includes: utilizing a detection circuit to perform a first physical resource block bundling detection in a first direction of the time-frequency domain to detect if at least one neighboring physical resource block is allowed to be bundled with the physical resource block, and accordingly generating a first physical resource block bundling detection result; determining a physical resource block processing range according to at least the first physical resource block bundling detection result, wherein at least the physical resource block is included in the physical resource block processing range; obtaining a plurality of pilot channels for pilot resource elements in the physical resource block processing range; and estimating the data channel of the data resource element according to the pilot channels.