A receiver circuit comprising: a quadrature passive mixer having an input, an LC tank (318, 320) coupled to the input, a local oscillator "LO" generating a frequency F LO and driving the mixer near a desired input signal frequency, two load networks (308A, 308B, CI, CQ, 810, 812, 814, 816), each of which presents a low pass impedance response near zero frequency and a high impedance response at twice the local oscillator frequency, a quadrature output (704, 708) having a first pair of output terminals and an in-phase output (702, 706) having a second pair of output terminals, and wherein an input impedance of the quadrature passive mixer provides a band-pass response and wherein each of the in-phase output and the quadrature phase outputs are connected to one of the load networks; and wherein each of the load networks interacts with time varying properties of the mixer to provide a band-pass response at the input; one or more output impedances coupled to the outputs of the quadrature passive mixer, wherein the one or more output impedances coupled to the quadrature passive mixer comprise one or more capacitors (CI, CQ) across said first pair of output terminals and one or more capacitors across said second pair of output terminals which act to set the bandwidth of the band-pass response provided at the input of the quadrature passive mixer which is centered close to the F LO or reference frequency; a low noise amplifier having an input and an output coupled to the quadrature passive mixer, the low noise amplifier configured to provide substantially linear transconductance over a predetermined input range wherein the low noise amplifier output is connected to the input of the quadrature passive mixer. a quadrature passive mixer having an input, an LC tank (318, 320) coupled to the input, a local oscillator "LO" generating a frequency F LO and driving the mixer near a desired input signal frequency, two load networks (308A, 308B, CI, CQ, 810, 812, 814, 816), each of which presents a low pass impedance response near zero frequency and a high impedance response at twice the local oscillator frequency, a quadrature output (704, 708) having a first pair of output terminals and an in-phase output (702, 706) having a second pair of output terminals, and wherein an input impedance of the quadrature passive mixer provides a band-pass response and wherein each of the in-phase output and the quadrature phase outputs are connected to one of the load networks; and wherein each of the load networks interacts with time varying properties of the mixer to provide a band-pass response at the input; one or more output impedances coupled to the outputs of the quadrature passive mixer, wherein the one or more output impedances coupled to the quadrature passive mixer comprise one or more capacitors (CI, CQ) across said first pair of output terminals and one or more capacitors across said second pair of output terminals which act to set the bandwidth of the band-pass response provided at the input of the quadrature passive mixer which is centered close to the F LO or reference frequency; a low noise amplifier having an input and an output coupled to the quadrature passive mixer, the low noise amplifier configured to provide substantially linear transconductance over a predetermined input range wherein the low noise amplifier output is connected to the input of the quadrature passive mixer.