Sample Rate Conversion in Software Radio Terminals
Tim Hentschel, M. Henker, Gerhard Paul Fettweis · 1999
Feasibility of Software Radio mainly depends on the availability of a suitable hardware platform. A basic feature of this hardware platform is the ability to process signals of different mobile communications standards, which are usually based upon a diversity of master clock rates. Hence, the conversion between different sample rates is an important functionality of a Software Radio receiver. Preferably realized digitally, sample-rate conversion is conventionally regarded as interpolation. It will be shown that interpolation does not fulfill the anti-aliasing requirement which is the very criterion to be obeyed. Based upon this idea anti-aliasing filters for sample rate conversion are proposed. These filters are realized by a multi stage system with different stages for integer-factor and fractional sample rate conversion.