Radio frequency implementation of the fractional Hilbert transform with transversal filters

In this paper, we discuss the design and the implementation of the fractional Hilbert transform using transversal filters. To demonstrate the design approach we also present the circuit design of a fractional Hilbert transform filter based on a fully differential transversal structure using a 0.18 mu m complementary metal oxide semiconductor (CMOS) process. Simulation results predict the synthesis of fractional phase shifts phi such that 60 degrees < vertical bar phi vertical bar < 120 degrees over a frequency range of about 300 MHz to 1 GHz.