A receiver front-end supporting contiguous and non-contiguous intra-band carrier aggregation scenarios with a fully integrated spectrum sensor that can detect both in-gap and out-of-band blockers has been implemented in 65nm CMOS technology. An NF of 2.5dB is achieved using a noise canceling LNTA, and linearized OTAs are used to achieve an IIP3 improvement of up to 6.5dB in-band and 11dB at the filter band edge. The spectrum sensor can detect blocker levels in 22 steps of 9MHz between -100MHz and 100MHz IF. The system consumes between 36.6mA and 57.6mA from a 1.2V supply.