Wide-band receiver architecture with flexible blocker filtering techniques

Wide-band filterless RF front-ends are yet unpractical because of the stringent linearity requirements imposed by out-of-band blockers. A base-band to radio-frequency feedback receiver (BB-RF-FBRX) architecture is proposed in this paper, which reflects the base-band selectivity to the RF input. The aim of this architecture is to eliminate surface acoustic wave (SAW) filters between the antenna and the low noise amplifier (LNA). Two variants of BB-RF feedback are analyzed and explored by simulation. The most promising positive feed-back architecture should allow up to 19 dB rejection of out-of-band interferers.