{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,30]],"date-time":"2025-12-30T11:19:45Z","timestamp":1767093585346,"version":"build-2065373602"},"reference-count":30,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2021,8,5]],"date-time":"2021-08-05T00:00:00Z","timestamp":1628121600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2020R1A2C1008484"],"award-info":[{"award-number":["2020R1A2C1008484"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002643","name":"Kwangwoon University","doi-asserted-by":"publisher","award":["Research Grant 2020"],"award-info":[{"award-number":["Research Grant 2020"]}],"id":[{"id":"10.13039\/501100002643","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A MedRadio RF receiver integrated circuit for implanted and wearable biomedical devices must be resilient to the out-of-band (OOB) orthogonal frequency division modulation (OFDM) blocker. As the OFDM is widely adopted for various broadcasting and communication systems in the ultra-high frequency (UHF) band, the selectivity performance of the MedRadio RF receiver can severely deteriorate by the second-order intermodulation (IM2) distortion induced by the OOB OFDM blocker. An analytical investigation shows how the OFDM-induced IM2 distortion power can be translated to an equivalent two-tone-induced IM2 distortion power. It makes the OFDM-induced IM2 analysis and characterization process for a MedRadio RF receiver much simpler and more straightforward. A MedRadio RF receiver integrated circuit with a significantly improved resilience to the OOB IM2 distortion is designed in 65 nm complementary metal-oxide-semiconductor (CMOS). The designed RF receiver is based on low-IF architecture, comprising a low-noise amplifier, single-to-differential transconductance stage, quadrature passive mixer, trans-impedance amplifier (TIA), image-rejecting complex bandpass filter, and fractional phase-locked loop synthesizer. We describe design techniques for the IM2 calibration through the gate bias tuning at the mixer, and the dc offset calibration that overcomes the conflict with the preceding IM2 calibration through the body bias tuning at the TIA. Measured results show that the OOB carrier-to-interference ratio (CIR) performance is significantly improved by 4\u201311 dB through the proposed IM2 calibration. The measured maximum tolerable CIR is found to be between \u221240.2 and \u221271.2 dBc for the two-tone blocker condition and between \u221270 and \u221277 dBc for the single-tone blocker condition. The analytical and experimental results of this work will be essential to improve the selectivity performance of a MedRadio RF receiver against the OOB OFDM-blocker-induced IM2 distortion and, thus, improve the robustness of the biomedical devices in harsh wireless environments in the MedRadio and UHF bands.<\/jats:p>","DOI":"10.3390\/s21165303","type":"journal-article","created":{"date-parts":[[2021,8,5]],"date-time":"2021-08-05T21:43:53Z","timestamp":1628199833000},"page":"5303","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["A CMOS RF Receiver with Improved Resilience to OFDM-Induced Second-Order Intermodulation Distortion for MedRadio Biomedical Devices and Sensors"],"prefix":"10.3390","volume":"21","author":[{"given":"Yongho","family":"Lee","sequence":"first","affiliation":[{"name":"Department of Electronics Convergence Engineering, Kwangwoon University, Seoul 01897, Korea"}]},{"given":"Shinil","family":"Chang","sequence":"additional","affiliation":[{"name":"Department of Electronics Convergence Engineering, Kwangwoon University, Seoul 01897, Korea"}]},{"given":"Jungah","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Electronics Convergence Engineering, Kwangwoon University, Seoul 01897, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1141-3428","authenticated-orcid":false,"given":"Hyunchol","family":"Shin","sequence":"additional","affiliation":[{"name":"Department of Electronics Convergence Engineering, Kwangwoon University, Seoul 01897, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,5]]},"reference":[{"key":"ref_1","unstructured":"Federal Communications Commission (FCC) (2009). Report and Order 09\u201323, Federal Communications Commission (FCC)."},{"key":"ref_2","unstructured":"Federal Communications Commission (FCC) (2011). Report and Order 11\u2013176, Federal Communications Commission (FCC)."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"483","DOI":"10.1109\/JBHI.2016.2639587","article-title":"Bio-WiTel: A Low-Power Integrated Wireless Telemetry System for Healthcare Applications in 401\u2013406 MHz Band of MedRadio Spectrum","volume":"22","author":"Srivastava","year":"2018","journal-title":"IEEE J. Biomed. Health Inf."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"2580","DOI":"10.1002\/mop.28650","article-title":"A CMOS Transceiver for Implantable Cardioverter Telemetry Service","volume":"56","author":"Kim","year":"2014","journal-title":"Microw. Opt. Technol. Lett."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Bradley, P.D. (2011, January 12\u201316). Wireless Medical Implant Technology-Recent Advances and Future Developments. Proceedings of the European Solid-State Circ. Conf. (ESSCIRC), Helsinki, Finland.","DOI":"10.1109\/ESSCIRC.2011.6044911"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"3152","DOI":"10.1109\/TCSI.2013.2265973","article-title":"Circuits for a Cubic-Millimeter Energy-Autonomous Wireless Intraocular Pressure Monitor","volume":"60","author":"Ghaed","year":"2013","journal-title":"IEEE Trans. Circuits Syst. I Reg. Pap."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"14","DOI":"10.1109\/JETCAS.2012.2187469","article-title":"Low-Invasive Implantable Devices of Low-Power Consumption Using High-Efficiency Antennas for Cloud Health Care","volume":"2","author":"Yang","year":"2012","journal-title":"IEEE J. Emerg. Sel. Top. Circuits Syst."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"29467","DOI":"10.3390\/s151129467","article-title":"Wireless Low-Power Integrated Basal-Body-Temperature Detection Systems Using Teeth Antennas in the MedRadio Band","volume":"15","author":"Yang","year":"2015","journal-title":"Sensors"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"227","DOI":"10.1109\/TBCAS.2015.2416253","article-title":"A Visual-Aided Wireless Monitoring System Design for Total Hip Replacement Surgery","volume":"9","author":"Chen","year":"2015","journal-title":"IEEE Trans. Biomed. Circuits Syst."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"538","DOI":"10.1109\/JSSC.2018.2873630","article-title":"A Four-Camera VGA-Resolution Capsule Endoscope System with 80-Mb\/s Body Channel Communication Transceiver and Sub-Centimeter Range Capsule Localization","volume":"54","author":"Jang","year":"2019","journal-title":"IEEE J. Solid State Circuits"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"101","DOI":"10.26866\/jees.2019.19.2.101","article-title":"An Ultra-Wideband Conformal Meandered Loop Antenna for Wireless Capsule Endoscopy","volume":"19","author":"Kim","year":"2019","journal-title":"J. Electromagn. Eng. Sci."},{"key":"ref_12","first-page":"910","article-title":"A 0.33 nJ\/bit IEEE802.15.6\/Proprietary MICS\/ISM Wireless Transceiver with Scalable Data Rate for Medical Implantable Applications","volume":"19","author":"Ba","year":"2015","journal-title":"IEEE J. Biomed. Health"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1541","DOI":"10.1109\/JSSC.2019.2899521","article-title":"A CMOS MedRadio Transceiver with Supply-Modulated Power Saving Technique for an Implantable Brain-Machine Interface System","volume":"54","author":"Lee","year":"2019","journal-title":"IEEE J. Solid State Circuits"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1846","DOI":"10.1109\/TMTT.2011.2138153","article-title":"A CMOS MedRadio Receiver RF Front-End with a Complementary Current-Reuse LNA","volume":"59","author":"Cha","year":"2011","journal-title":"IEEE Trans. Microw. Theory Techn."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1627","DOI":"10.1109\/TCSI.2015.2415179","article-title":"A 1.3 mW Low-IF, Current-Reuse, and Current-Bleeding RF Front-End for the MICS Band with Sensitivity of \u221297 dBm","volume":"62","author":"Cruz","year":"2015","journal-title":"IEEE Trans. Circuits Syst. I Reg. Pap."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"73","DOI":"10.1109\/LMWC.2015.2505614","article-title":"A 370 \u03bcW CMOS MedRadio Receiver Front-End with Inverter-Based Complementary Switching Mixer","volume":"26","author":"Choi","year":"2016","journal-title":"IEEE Microw. Wirelss Compon. Lett."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"748","DOI":"10.5573\/JSTS.2018.18.6.748","article-title":"A CMOS Receiver Front-end with Fractional-N PLL Synthesizer for MedRadio Applications","volume":"18","author":"Lee","year":"2018","journal-title":"IEEE J. Semicond. Tech. Sci."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"3459","DOI":"10.1109\/JSSC.2009.2032592","article-title":"A 10.8 mW Body Channel Communication\/MICS Dual-Band Transceiver for a Unified Body Sensor Network Controller","volume":"44","author":"Cho","year":"2009","journal-title":"IEEE J. Solid State Circuits"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"3197","DOI":"10.1109\/JSSC.2012.2216706","article-title":"A 915 MHz, Ultra-Low Power 2-Tone Transceiver with Enhanced Interference Resilience","volume":"47","author":"Huang","year":"2012","journal-title":"IEEE J. Solid State Circuits"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"3114","DOI":"10.1109\/JSSC.2016.2602943","article-title":"A 915 MHz 175 mW Receiver Using Transmitted-Reference and Shifted Limiters for 50 dB In-Band Interference Tolerance","volume":"51","author":"Ye","year":"2016","journal-title":"IEEE J. Solid State Circuits"},{"key":"ref_21","unstructured":"Advanced Television Systems Committee (ATSC) (2018). ATSC Standard-Physical Layer Protocol, Advanced Television Systems Committee (ATSC). Doc. A\/322: 2018."},{"key":"ref_22","unstructured":"European Telecommunications Standards Institute (ETSI) (2015). Digital Video Broadcasting (DVB)-Frame Structure Channel Coding and Modulation for a Second Generation Digital Terrestrial Television Broadcasting System (DVB-T2), European Telecommunications Standards Institute (ETSI). ETSI EN 302 755 V1.4.1."},{"key":"ref_23","unstructured":"Association of Radio Industries and Businesses (ARIB) (2014). Transmission System for Digital Terrestrial Television Broadcasting, Association of Radio Industries and Businesses (ARIB). ARIB STD-B31 V2.2."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"4422","DOI":"10.1109\/TMTT.2006.882870","article-title":"Distortion Analysis of Ultra-Wideband OFDM Receiver Front-Ends","volume":"54","author":"Ranjan","year":"2006","journal-title":"IEEE Tran. Microw. Theory Tech."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Kim, J., Lee, Y., Chang, S., and Shin, H. (2020). Low-Power CMOS Complex Bandpass Filter with Passband Flatness Tunability. Electronics, 9.","DOI":"10.3390\/electronics9030494"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"730","DOI":"10.5573\/JSTS.2018.18.6.730","article-title":"A 1-V 3.8-mW Fractional-N PLL Synthesizer with 25% Duty-Cycle LO Generator in 65 nm CMOS for Bluetooth Applications","volume":"18","author":"Lee","year":"2018","journal-title":"IEEE J. Semicond. Tech. Sci."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"718","DOI":"10.1109\/JSSC.2009.2013762","article-title":"A Single-Chip 10-Band WCDMA\/HSDPA 4-Band GSM\/EDGE SAW-less CMOS Receiver with DigRF 3G Interface and +90 dBm IIP2","volume":"44","author":"Kaczaman","year":"2009","journal-title":"IEEE J. Solid-State Circuits"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"4589","DOI":"10.1109\/TMTT.2020.3009945","article-title":"2.4-GHz CMOS Bluetooth RF Receiver with Improved IM2 Distortion Tolerance","volume":"68","author":"Chang","year":"2020","journal-title":"IEEE Tran. Microw. Theory Tech."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Kim, S., Kim, D., Oh, S., Lee, D., Pu, Y., Hwang, K., Yang, Y., and Lee, K. (2019). A Fully Integrated Bluetooth Low-Energy Transceiver with Integrated Single Pole Double Throw and Power Management Unit for IoT Sensors. Sensors, 19.","DOI":"10.3390\/s19102420"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Li, D., Liu, D., Kang, C., and Zou, X. (2017). A Low Power Low Phase Noise Oscillator for MICS Transceivers. Sensors, 17.","DOI":"10.3390\/s17010140"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/16\/5303\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:41:13Z","timestamp":1760164873000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/16\/5303"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,8,5]]},"references-count":30,"journal-issue":{"issue":"16","published-online":{"date-parts":[[2021,8]]}},"alternative-id":["s21165303"],"URL":"https:\/\/doi.org\/10.3390\/s21165303","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2021,8,5]]}}}