A 30-MHz-2.4-GHz CMOS receiver with integrated RF filter and dynamic-range-scalable energy detector for cognitive radio systems

Masaki Kitsunezuka, Hiroshi Kodama, Naoki Oshima, Kazuaki Kunihiro, Tadashi Maeda, Muneo Fukaishi

Research output: Contribution to journalArticle

45 Citations (Scopus)


A 30-MHz-2.4-GHz complementary metal oxide semiconductor (CMOS) receiver with an integrated tunable RF filter and a dynamic-range-scalable energy detector for both white-space and interference-level sensing in cognitive radio systems is reported. The second-order RF filter has only two stacked transistors, and its use, in combination with a subsequent harmonic rejection mixer, results in wideband interference rejection. The energy detector with programmable rectifiers provides dynamic-range (DR) scalability, enabling shared use for white-space/interference-level detection and automatic gain control. A prototype chip, fabricated using 90-nm CMOS technology, achieved over 42-dB harmonic rejection including 7th-order component without any external device, a 67-dB gain, a 5-8-dB noise figure, a $-$11-dBm in-band third-order intercept point, and a $+$38-dBm second-order intercept point while drawing only 25-37 mA from a 1.2-V power supply. Multi-resolution DR-scalable spectrum sensing with a 0.2-30-MHz detection bandwidth, $-$83-dBm minimum sensitivity, and a 29-48-dB DR was demonstrated.

Original languageEnglish
Article number6155617
Pages (from-to)1084-1093
Number of pages10
JournalIEEE Journal of Solid-State Circuits
Issue number5
Publication statusPublished - 2012 May
Externally publishedYes



  • Cognitive radio
  • energy detector
  • harmonic rejection mixer
  • RF filter
  • RSSI
  • spectrum sensing
  • tunable filter
  • wideband receiver

ASJC Scopus subject areas

  • Electrical and Electronic Engineering

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