This paper proposes cyclostationary feature detection (CFD) based spectrum sensor for cognitive radio technology that consumes lower hardware resources and delivers shorter sensing time. We have addressed the challenge of efficiently implementing complex frequency-domain based CFD spectrum-sensing algorithm. Specifically, VLSI-architecture of 2048-point FFT module has been multi-level resource shared for the optimization. In addition, performance analyses results of our spectrum sensor are presented for 1024, 2048 and 4096 point FFT sizes where the proposed design delivered adequate detection-probability of 0.9 at -5 dB of SNR. This spectrum sensor is FPGA implemented and it showed that the hardware utilization has been improved due to 100% reduction in memory requirement and has archived a shorter sensing time of 0.4 ms which is 12.5 times lesser compared to the state-of-the-art work.