Title :
Searching for Spectrum Holes: A 400–800 MHz Spectrum Sensing System
Author :
Hsiao-Chin Chen ; Ming-Yu Yen ; Kuo-Jin Chang
Author_Institution :
Dept. of Electr. Eng., Nat. Taiwan Univ. of Sci. & Technol., Taipei, Taiwan
Abstract :
A 400-800 MHz spectrum sensing system is designed and implemented using 0.18-μm CMOS technology for cognitive radios in the UHF TV band. Based on envelope detection, the system employs a down converter, a digitally controlled oscillator, a low-pass filter (LPF), a rectifier, a comparator, and a digital control unit to realize spectrum sensing with 10-bit frequency representation. With variable-gain function of the LPF, signal strength can be measured and presented with a 5-bit signal strength index.
Keywords :
CMOS integrated circuits; UHF integrated circuits; cognitive radio; comparators (circuits); low-pass filters; oscillators; rectifying circuits; signal detection; CMOS technology; UHF TV band; cognitive radio; comparator; digital control unit; digitally controlled oscillator; frequency 400 MHz to 800 MHz; low-pass filter; rectifier; size 0.18 mum; spectrum hole searching; spectrum sensing system; Frequency control; Gain; Mixers; Oscillators; Receivers; Sensors; Analog-to-Digital Converters (ADCs); cognitive radios (CRs); digital controlled oscillators (DCOs); receivers; software-defined radios; spectrum sensing; spectrum sensing.;
Journal_Title :
Very Large Scale Integration (VLSI) Systems, IEEE Transactions on
DOI :
10.1109/TVLSI.2014.2387283
