I. Introduction
Bluetooth [1] and digital European cordless telecommunication (DECT) [2], [3] implement short-range wireless communications, which enable ad hoc networking between various devices and terminals. Currently, Bluetooth relies on a continuous-phase-modulation (CPM) scheme termed Gaussian frequency shift keying (GFSK). Like Gaussian minimum shift keying [4], GFSK can be regarded as a digital-frequency-modulation (FM) scheme. The success of Bluetooth and DECT is indispensibly connected to the availability of inexpensive terminals, which must rely on simple and powerful receivers. Usually, receiver structures are based on a conventional system model, cf., e.g., [5, eq. (8)]. This conventional system model assumes regular, i.e., “equidistant,” sampling of the analog received signal prevailing in the complex-base-band domain. The resulting receivers, requiring a considerable amount of analog and mixed-signal hardware, are often rather elaborate.