A current-mode direct conversion RF
receiver is presented. In one set of embodiments the RF
receiver comprises a simple transconductor input stage to create a current-mode modulated
signal from a
voltage-mode modulated
signal. A downconversion mixer may be coupled to the transconductor input stage via a
low impedance current
cascode stage, and may operate to create a set of current-mode quadrature
baseband signals from the current-mode modulated
signal. The downconversion mixer may be implemented with a
transistor-switching network, which may be driven by a
phase locked loop (PLL) with quadrature outputs. The set of current-mode quadrature
baseband signals may be converted back to the
voltage domain by a transimpedance filter, which may perform channel selection for the
receiver. The transimpedance filter may additionally include a
low frequency zero to remove DC offsets. The receiver may be implemented using
CMOS design technologies and operated with minimal self-mixing effects, minimal DC offset in the
baseband signal, and utilizing low voltages.